Objective To analyze the detection of helicobacter pylori(Hp)in different parts of gastric antrum,and to provide clinical guidance for finding the best biopsy site for Hp.Methods Patients who underwent 13C urea breath test and electronic gastroscopy from January 2020 to December 2022 were retrospectively analyzed and divided into 13C urea breath test positive group[delta over baseline(DOB)≥4]and 13C urea breath test negative group(DOB<4)according to DOB value.Gastroscopy reports and pathological data of patients were collected.According to different biopsy sites in gastric antrum,patients were divided into conventional biopsy site group,elevated erosive site group and flat erosive site group,and the detection rate of Hp in different biopsy sites was compared.13C urea breath test positive group was divided into group A(435)according to DOB value,and the gastric antral biopsy and pathology of each group were classified and analyzed.Combined with endoscopic reports and pathological data,patients were divided into atrophic gastritis group and non-atrophic gastritis group.Results In the 13C urea breath test positive group,the detection rate of Hp in the elevated erosive site group(96.4%)was higher than that in the conventional biopsy site group(92.7%)and the flat erosive site group(93.9%),and the difference was statistically significant(P = 0.036).In DOB group A,the detection rate of Hp was the highest at the site of elevated erosive and the lowest at the site of conventional biopsy,and the detection rate of Hp at the three biopsy sites was compared,the difference was statistically significant(P = 0.016);There was no significant difference in the detection rate of Hp at three biopsy sites between group B and group C(P = 0.622;P = 0.721);the non-atrophic gastritis group,the detection rate of Hp at the elevated erosive site(96.5%)was higher than that at the conventional biopsy site(91.2%)and the flat erosive site(92.0%),and the difference was statistically significant(P = 0.043).There was no significant difference in the detection rate of Hp at three biopsy sites in the atrophic gastritis group(P = 0.614).13C urea breath test negative group:There was no significant difference in Hp detection rate among the three biopsy sites(P = 0.255).Conclusion For patients with positive 13C urea breath test but low DOB value,the positive rate of Hp in the elevated erosive site is higher.For non-atrophic gastritis patients,the detection rate of Hp was higher in the elevated erosive sites than in the conventional biopsy sites.But for patients with atrophic gastritis,there was little difference in the detection rate of Hp in different parts of antrum.For patients with negative 13C urea breath test,there was no significant difference in Hp detection rate among the three biopsy sites.In future clinical work,for similar patients,precise biopsy can be performed to improve the detection rate of Hp.

Objective:To prepare the hydrogel scaffolds with different concentrations of laponite and compare their osteogenic properties.Methods:The scaffolds of gelatin/sodium alginate hydrogel into which laponite was added according to the mass ratios of 0%, 1%, 2%, and 3% were assigned into groups T0, T1, T2, and T3. In each group, the compressive modulus was measured and the leaching solution for 24 h extracted to measure the ion release. Bone marrow mesenchymal stem cells (BMSCs) were cultured in the extract medium from each group and common medium (blank group) ( n=3) in the in vitro experiments to determine the expression of osteogenic genes Runt-related transcription factor 2 (Runx2), alkaline phosphatase (ALP) and type I collagen after 7 days of culture. In the in vivo experiments, the scaffolds were implanted into the femoral condyle defects in rats, and a blank group with no scaffolds was set. The bone repair in each group was evaluated by hematoxylin-eosin(HE) staining and immunohistochemical staining. Results:The compressive modulus in group T2 [(139.05±6.43) kPa] was significantly higher than that in groups T0, T1 and T3 [(68.83±3.76) kPa, (101.18±3.68) kPa and (125.40±3.28) kPa] ( P<0.05). The ion contents of lithium, magnesium and silicon released from the 24 h leaching solution in group T2 were (0.031±0.005) μg/mL, (3.047±0.551) μg/mL and (5.243±0.785) μg/mL, insignificantly different from those in group T3 ( P> 0.05) but significantly larger than those in group T1 ( P>0.05). The in vitro experiments showed that the expression levels of Runx2, ALP and type I collagen in group T2 were 1.59±0.11, 2.02±0.08 and 1.06±0.17, significantly higher than those in the other groups ( P<0.05). HE staining showed that the implanted hydrogel was tightly bound to the bone tissue. Immunohistochemical staining showed that the numbers of Runx2 and osteocalcin positive cells in group T2 were significantly higher than those in the other groups. Conclusions:With ideal biocompatibility, hydrogel scaffolds with different concentrations of laponite can slowly release the decomposed ions of lithium, magnesium and silicon to promote the osteogenic differentiation of BMSCs and the repair of bone defects in vivo. A 2% concentration of laponite in the hydrogel scaffolds may result in the best results.