Objective:To study the effects of SiO2 nanoparticles on the organs of mice in vivo after intratracheal instillation, and to provide the basis for safety evaluation of SiO2 nanoparticles. Methods:Forty female BALB/c mice aged 6-8 weeks were randomly divided into control group (saline), low dose of SiO2 group (7 mg·kg-1), middle dose of SiO2 group (21 mg·kg-1), and high dose of SiO2 group (35 mg·kg-1).1 and 15 d after five times of non-exposed intratracheal instilation infection (once every 3 d), the mice were sacrificed and the left lungs,the right kidneys, livers, hearts and spleens were collected and embedded in paraffin.The morphology of tissue sections was observed under light microscope after hematoxylin-eosin (HE) staining.The eyeball blood was obtained and the biochemical indicators of liver and kidndy functions were detected.Results:Compared with control group, there were alveolar interval thickening, inflammatory cell infiltration, and a small amount of small arterial thrombosis in the lungs;granulomatous inflammatory cell infiltration and a small amount of focal necrosis of liver cells in the livers;red pulp enlargement, hyperemia, and more visibly scattered megakaryocytes in the spleens in SiO2 nanoparticles groups in a dose-dependent manner, especially in middle and high doses of SiO2 groups.After 15 d of injection, the damages alleviated with the prolongation of time.There was some inflammatory cell infiltration in the kidney tissue of the mice in SiO2 nanoparticle groups.The biochemical indicator detection results showed that alanine aminotransferase(ALT) and aspartate transaminase(AST) levels in SiO2 nanoparticles groups varied, suggesting the liver cell damages were at different degrees;the changes of urea nitrogen(BUN) and creatinine(Cr) levels in SiO2 nanoparticle groups remindered the kidney function alteration, but there were no obvious dose-and time-dependent effects.Conclusion:Intratracheal instillation of SiO2 nanoparticles can influence the major organs of the mice and mainly displays in the inflammation and injuries in the lung, liver, and spleen.

BACKGROUND:Numerous scholars have previously researched certain greater tuberosity fractures and the procedures used to treat them.Few researchers,however,have studied the comminuted split fracture of the greater tuberosity of the humerus(Liu-Gang type IV)with rotator cuff tear in great detail. OBJECTIVE:To compare the clinical therapeutic effect of open repair position modified calcaneal plate combined with suture anchors and proximal humeral internal locking system(PHILOS)plate in the treatment of comminuted fracture of split-type greater tuberosity of humerus combined with rotator cuff tears(Liu-Gang type IV). METHODS:Case data of 30 patients with comminuted fracture of split-type greater tuberosity of humerus combined with rotator cuff tears(Liu-Gang type IV)from May 2012 to May 2022 were retrospectively analyzed.They were divided into the modified calcaneal plate combined with suture anchor group(group A)and the PHILOS with#2 Johnson group(group B),with 15 cases in each group.Intraoperative blood loss,surgical time,and incision length of all patients were recorded.Pain visual analog scale score,Constant-Murley score,as well as shoulder joint abduction,forward flexion,external rotation,and dorsal expansion activities during the last follow-up(>1 year)were evaluated. RESULTS AND CONCLUSION:(1)The surgical incision length and operation time were shorter,and blood loss was less in group A than those in group B(P<0.05).(2)No significant difference in visual analog scale score and Constant-Murley score was detected between the two groups(P>0.05).(3)During the last follow-up,forward flexion in group A was better than that in group B(P<0.05).No significant difference in abduction,external rotation,and dorsal expansion was determined between group A and group B(P>0.05).(4)In terms of complications,there was 1 case of shoulder joint pain and discomfort in group A(7%),2 cases of subacromial impingement syndrome,2 cases of upward movement of nodules,and 2 cases of shoulder joint pain(40%)in group B.There were significant differences in complication rates between the two groups(P=0.031).(5)In summary,the modified calcaneal plate combined with suture anchors in the treatment of comminuted fracture of split-type greater tuberosity of humerus combined with rotator cuff tears(Liu-Gang type IV)could better restore the forward flexion function of the shoulder joint and has a small incision,less blood loss,shorter operation time and fewer complications.