Objective To observe the effect of rotavirus (RV) infection on expression level and bioactivity of Na+-H+ exchanger 3 (NHE3) in Caco-2 cells. Methods Model of NHE3-expressing Caco-2 cells was constructed and studied in terms of intervention: control, RV, clathrin antagonist chlorpromazine (CPZ), and CPZ + RV. NHE3 activity and NHE3 protein amount on cell surface were determined by BCECF-AM and biotinylation, respectively. Expression level of clathrin was assayed by Western blot. Results Compared with control group, NHE3 activity and NHE3 surface protein level significantly decreased when the cells were treated with RV. These effects could not be completely cancelled by clathrin antagonist CPZ. Moreover, RV treatment could increase cellular protein level of clathrin, which was cancelled by CPZ. Conclusions The effect of RV infection on NHE3 expression level and biological activity may be related to clathrin-dependent endocytosis pathway, and may be also affected by other endocytosis pathways.

BACKGROUND:The displacement change parameters of the bone structure of the first metatarsal bone at the two-dimensional level of hallux valgus deformity are of great significance for clinical diagnosis and treatment,while the quantitative analysis of the three-dimensional deformity index may have some influences on the postoperative efficacy. OBJECTIVE:To explore the quantitative change of the three-dimensional deformity index of the first metatarsal bone after routine osteotomy and orthosis for hallux valgus deformity and to provide reference for clinical work. METHODS:100 patients with hallux valgus deformity(foot)in Hengshui People's Hospital from October 2020 to April 2023 were selected and all of them underwent conventional osteotomy and orthosis.Foot function was assessed by the American Orthopedic Foot and Ankle Society Ankle-Hindfoot Scale 6 months after surgery.Anterolateral X-rays of the foot in weight-bearing position and CT images in simulated weight-bearing position were taken before surgery and 6 months after surgery.The three-dimensional deformity indexes of the first metatarsal bone before and after surgery were quantitatively analyzed in patients with different ages,genders and therapeutic effects,including first-second intermetatarsal angle,hallux valgus angle,distal metatarsal articular angle,tibial sesamaid position,and first metatarsal rotation α angle.The value of the difference of three-dimensional deformity indexes of the first metatarsal bone before and after operation in evaluating the curative effect was analyzed. RESULTS AND CONCLUSION:(1)Six months after operation,the American Orthopedic Foot and Ankle Society score was 75-98(88.25±4.14)points,among which 56 cases were excellent,28 cases were good,14 cases were average,and 2 cases were poor.The excellent and good rate was 84%(84/100).(2)Compared with the preoperative results,first-second intermetatarsal angle,hallux valgus angle,distal metatarsal articular angle,tibial sesamaid position,and first metatarsal rotation α angle were significantly improved in patients of different ages and genders 6 months after surgery(P<0.05).First-second intermetatarsal angle,hallux valgus angle,distal metatarsal articular angle,tibial sesamaid position,and first metatarsal rotation α angle were all lower in patients with good curative effect 6 months after surgery than those with poor curative effect,and the difference before and after surgery was greater than those with poor curative effect(P<0.05).(3)The area under the curve of the difference evaluation of the first metatarsal three-dimensional deformity index before and after surgery was above 0.7,and the area under the curve of the combined evaluation of all indexes was the largest(0.902),which was significantly greater than the first metatarsal rotation α angle and distal metatarsal articular angle(P<0.05).(4)The quantitative analysis of the three-dimensional deformity index of the first metatarsal in patients with hallux valgus deformity is related to the postoperative effect,which has important guiding significance for improving the accuracy and comprehensiveness of preoperative evaluation and improving the treatment plan.

Objective To investigate the effects of rotavirus ( RV) on the expression and bioactiv-ity of Na+-H+ exchanger 3 ( NHE3 ) in Caco-2 cells and the possible regulatory mechanism. Methods Caco-2 cells expressing NHE3 were constructed and divided into four groups as follows: control ( CTL ) group, RV group, BAPTA-AM ( a Ca2+ chelator) group and BAPTA-AM+RV group. Na+-H+ exchanger ac-tivity and NHE3 expression on cell surface were determined using BCECF-AM and biotinylation assay, re-spectively. Expression of Cdc42 at protein level was measured by Western blot. Results Compared with the control group, RV infection significantly decreased the activity of NHE3 and its expression on cell surface. BATPA-AM antagonized the inhibitory effects on NHE3. Moreover, the expression of Cdc42 at protein level was increased following RV infection, which was also antagonized by BATPA-AM. Conclusions Intracellu-lar Ca2+-mediated Cdc42-dependent endocytosis pathway might be involved in regulating the expression and bioactivity of NHE3 during RV infection.