[Effects of novel bioactive glasses on promoting remineralization of artificial dentin caries].

OBJECTIVE: To investigate the effects of novel bioactive glasses (BG) including PSC with high phosphorus component and FBG with fluorine-doped element on promoting remineralization of artificial dentin caries. METHODS: (1) BGs were used in this study as follows: PSC (10.8%P2O5-54.2%SiO2-35.0%CaO, mol.%) were synthesized using phytic acid as the phosphorus precursor through sol-gel method. FBG (6.1%P2O5-37.0%SiO2-53.9%CaO-3.0%CaF2, mol.%) and 45S5(6.0%P2O5-45.0%SiO2-24.5%CaO-24.5%Na2O, mol.%) were synthesized by traditional melt method. (2) The above BGs were soaked in simulated body fluid (SBF) for 24 hours. Then X-ray diffraction (XRD) was used to analyze the formation of hydroxyapatite (HA) crystals. (3) Prepared 1 mm thick dentin slices were soaked in 17% ethylene diamine tetraacetic acid (EDTA) for 1 week to demineralize the dentin. Then the dentin slices treated by BG were soaked in SBF for 1 week. Field emission scanning electron micro-scopy (FE-SEM) was used to observe the surface morphology of the dentin slices. (4) Four cavities were prepared to 1 mm depth in each 2 mm thick dentin slice, then were treated with lactic acid for 2 weeks to form the artificial dentin caries. Wax, mineral trioxide aggregate (MTA), PSC and FBG were used to fill four cavities as blank control group, MTA group, PSC group and FBG group respectively. Then the spe-cimens were soaked in SBF for 4 weeks. The changes of depth and density of demineralized dentin were analyzed using Micro-CT before filling and after 2 and 4 weeks filling. RESULTS: (1) PSC and FBG promoted mineral formation on the surfaces of the demineralized dentin. And the speed was faster and crystallinity was higher in PSC group than the FBG and 45S5 groups. (2) The increased mineral density of artificial dentin caries in PSC group were (185.98 ± 55.66) mg/cm3 and (213.64 ± 36.01) mg/cm3 2 and 4 weeks after filling respectively, which were significantly higher than the control group [(20.38 ± 7.55) mg/cm3, P=0.006; (36.46 ± 10.79) mg/cm3, P=0.001]. At meanwhile, PSC group was also higher than MTA group [(57.29 ± 10.09) mg/cm3; (111.02 ± 22.06) mg/cm3], and it had statistical difference (P=0.015; P=0.006). The depth of remineralized dentin in PSC group were (40.0 ± 16.9) µm and (54.5 ± 17.8) µm 2 and 4 weeks respectively, which were also statistically different from the control group (P =0.010;P=0.001). There were no statistical differences between the control group and MTA group. The above effects of FBG group were between PSC and MTA. CONCLUSION: PSC has advantages in the speed, quality and depth of mineral deposition in the demineralized layer of artificial dentin caries. It would be expected to be an ideal material to promote the remineralization of dentin caries.

Jupiter's X-Ray and UV Dark Polar Region.

We present 14 simultaneous Chandra X-ray Observatory (CXO)-Hubble Space Telescope (HST) observations of Jupiter's Northern X-ray and ultraviolet (UV) aurorae from 2016 to 2019. Despite the variety of dynamic UV and X-ray auroral structures, one region is conspicuous by its persistent absence of emission: the dark polar region (DPR). Previous HST observations have shown that very little UV emission is produced by the DPR. We find that the DPR also produces very few X-ray photons. For all 14 observations, the low level of X-ray emission from the DPR is consistent (within 2-standard deviations) with scattered solar emission and/or photons spread by Chandra's Point Spread Function from known X-ray-bright regions. We therefore conclude that for these 14 observations the DPR produced no statistically significant detectable X-ray signature.

[The prevention and management of approach-specific complications of abdominal aortic balloon occlusion in pelvic and sacral surgery].

Objective: To investigate the causes,prevention and treatment of femoral artery puncture related complications caused by the application of resuscitative endovascular balloon occlusion of the aorta (REBOA) in the resection of pelvic and sacral tumors. Methods: Clinical data of 23 patients with femoral artery puncture related complications who received REBOA in the resection of pelvic and sacral tumors from August 2010 to August 2018 at the Musculoskeletal Tumor Center,Peking University People's Hospital were retrospectively analyzed.There were 8 males and 15 females,with the an age of (37.0±16.2) years (range:15 to 65 years).Arterial access via the Seldinger technique for REBOA was obtained in the right common femoral artery of 18 cases,and in the left of 6 cases.An arterial sheath with a diameter of 11 to 12 F(1 F≈0.33 mm) was used for the patient.The occurrence and treatment of postoperative complications were analyzed. Results: Acute femoral arterial thrombosis occurred in 18 patients,which was managed by open repair 48 hours postoperatively.Among the 349 patients admitted before 2015 who received hemostasis by compression after femoral artery sheath removal,12 patients (3.4%) developed acute femoral artery thrombosis.While the 476 patients admitted after 2015 who used a vascular stapler to close the femoral artery wound,6 patients (1.3%) developed acute femoral artery thrombosis.One case of retroperitoneal hematoma and 1 case of femoral pseudoaneurysm were found and surgically fixed.Postoperative follow-up was (40±18) months (range:13 to 108 months).Three cases with chronic lower extremity ischemia were confirmed by Doppler ultrasonography during 1 to 5 years follow-up.Two of them had minimal symptoms and denied further treatment,while the other one received femoral-femoral artery bypass surgery to restore distal flow for pain and numbness relief. Conclusions: Acute femoral arterial thrombosis was the most common femoral artery puncture.Technique refinement of REBOA,the use of percutaneous suture device and close follow-up can reduce the approach-specific complications,and help to detect and treat the complications timely,which may popularize the clinical application of REBOA.

The regulatory role of SLP-2 and mechanism on CCBE1 gene expression in rectal carcinoma and adjacent lymphatic tube tissues.

OBJECTIVE: The incidence of rectal carcinoma (RC) has been increasing recently, and becomes the second most common digestive tumors besides gastric cancer, with a rise in the incidence of RC in younger populations. The early diagnosis and treatment are thus critical for the improvement of survival rate and life quality of patients. Stomatin-like protein 2 (SLP-2) is a type of membrane factor, which is generally found highly expressed in various tumors. Collagen and calcium-binding EGF domain (CCBE1) belongs to lymphatic tube genesis factor. The regulatory role of SLP-2 gene on CCBE1 expression in RC tumor and adjacent lymphatic tube tissues, however, has not been studied. PATIENTS AND METHODS: 52 RC patients were recruited, and tumor and adjacent lymphatic tube tissues were collected. Real-time PCR, western blotting and immunohistochemistry (IHC) staining were used to analyze SLP-2 and CCBE1 expressions. Human lymphatic endothelial cells (LECs) were cultured in vitro and were assigned to control, scramble, and SLP-2 siRNA group. MTT assay was used to detect cell proliferation, while caspase 3 activity was detected. RESULTS: SLP-2 and CCBE1 levels were significantly elevated in tumor lymphatic tissues, compared to that in adjacent tissues. Statistically positive correlation between SLP-1 and CCBE2 was found (p<0.05). The downregulation of SLP-2 by siRNA inhibited cell proliferation, elevated caspase3 activity, and decreased CCBE1 expression (p<0.05 compared to control group). CONCLUSIONS: SLP-2 is up-regulated in RC lymphatic tissues, and is positively correlated with the level of CCBE1, which provides the academic the basis for the development of medicine targeting SLP-2 in the anti-rectal carcinoma therapy.

[Diagnosis and treatment of strabismus caused by nasal endoscopic surgery].

Objective: Strabismus with diplopia is the main orbital complication of functional endoscopic sinus surgery (FESS). This study was to analyze clinical findings, treatment and outcomes of such cases. Methods: Retrospective case series. Twenty-three cases were divided into 3 groups based on the disease severity: group A, partial transection of the medial rectus muscle, group B, complete transection of the medical rectus, group C, transection of the medial rectus combined with the other orbital injuries. Complete ophthalmology examinations, including eye alignment, eye motility, force duction test, force generation test, general eye exam, and medical imaging (orbital CT or MRI), were performed for each case. The treatment included botulinum toxin (Botox) injection to the lateral rectus muscle, transposition of the vertical rectus muscle, and orbital surgery if needed. Results: In group A with Botox injection, all the cases achieved single vision in primary position, but still remained some adduction weakness. In group B treated by vertical transposition surgery combined with Botox, 22% of the cases got single vision in primary gaze. In group C, even with more efforts of treatment, the cases with orbital injury can only get cosmetic improvement, and diplopia and adduction dysfunction were found in most cases. Conclusions: Due to the variety of the complications of FESS, force duction test is a crucial exam to detect the direction and severity of synechia in the orbit, which will give solid information to surgery approach as well as prognosis. Botox injection at early stage will minimize the contraction of antagonist lateral rectus, helping to postpone the transposition surgery which may cause anterior segment ischemia when performed right after the medial rectus transection injury. Botox may even reduce the synechia by minimizing the scarring process. Partial vertical rectus transposition combined with muscle resection may effectively correct the eye misalignment in primary gaze and improve eye motility. The prognosis of FESS induced orbital complications is quite related with the severity of the injury. Botox combined with surgery may help medial rectus transection cases to achieve single vision in primary gaze, but when there is any other orbital injury, treatment may only improve cosmetic appearance. (Chin J Ophthalmol, 2017, 53: 917-923).

Intranasal immunisation with Stx2B-Tir-Stx1B-Zot protein leads to decreased shedding in goats after challenge with Escherichia coli O157:H7.

Ruminants are an important reservoir of Escherichia coli O157:H7. To reduce E coli O157:H7 excretion by these animals could play a key role in prevention and control of human infections. In the present study, the authors used 12 three-month-old goats to evaluate the efficacy of intranasal administration of the Stx2B-Tir-Stx1B-Zot protein. These goats were inoculated on days 0 and 21 and infected with 10(10) colony-forming units (cfu) of E coli O157:H7 by oral inoculation on day 36. Faecal shedding was monitored daily for two weeks. All of six goats immunised with recombinant protein elicited significant Stx2b-Tir-Stx1b-Zot-specific serum IgG antibodies, and three of them also showed production of antigen-specific IgA in faeces. The immunised goats showed much less shedding of E coli O157:H7 after challenge. These results demonstrate the potential for the use of Stx2B-Tir-Stx1B-Zot protein in mucosal vaccine formulations to prevent colonisation and shedding of E coli O157:H7 in goats.