Association between dental fluorosis and serum biomarkers of bone metabolism in children / 中华地方病学杂志

Objective:This study was aimed to explore the associations between the risk of dental fluorosis and the serum biomarkers of bone metabolism in children.Methods:A total of 502 children aged 7 - 12 years were selected by cluster sampling from 4 primary schools in Tongxu County, Kaifeng City, Henan Province from April to May 2017. Morning urine and fasting peripheral blood samples were collected from each participant. Urinary fluoride concentration was determined by fluoride ion selective electrode method. Serum calcium, phosphorus, alkaline phosphatase (ALP), bone-specific alkaline phosphatase (BALP), osteocalcin (OC), calcitonin (CT) and parathyroid hormone (PTH) levels were measured using an automatic biochemical analyzer. Dean method was used to evaluate the prevalence of dental fluorosis in children, and the participants were divided into dental fluorosis group ( n = 173) and control group ( n = 329) after being diagnosed by trained physicians for their dental fluorosis. The associations between the risk of dental fluorosis and the serum biomarkers of bone metabolism in children were analyzed by logistic regression. Results:The levels of serum phosphorus (mmol/L: 1.54 ± 0.19 vs 1.58 ± 0.21) and OC (ng/ml: 11.59 ± 5.22 vs 12.78 ± 5.88) in children in dental fluorosis group were significantly lower than those in children in control group ( P < 0.05). Logistic regression analysis showed that serum OC level affected the risk of dental fluorosis [odds ratio ( OR) = 0.96, 95% confidence interval ( CI): 0.92 - 0.99, P < 0.05]. The relative contribution of the biomarkers of bone metabolism to the risk of dental fluorosis in descending order were serum OC (36.34%), phosphorus (25.89%), BALP (13.16%), PTH (9.73%), calcium (9.44%), CT (3.72%) and ALP (1.72%). Conclusions:The prevalence of dental fluorosis in children is related to the changes of serum biomarkers of bone metabolism. Serum OC plays an important role in the occurrence of dental fluorosis.

Progress of unilateral breast cancer undergoing contralateral prophylactic mastectomy / 国际外科学杂志

A growing number of people with unilateral breast cancer have chosen to undergo contralateral prophylactic mastectomy in order to prevent the occurrence of second primary breast cancer and thus avoid associated treatment and death. Contralateral prophylactic mastectomy has been considered beneficial in high-risk populations, such as premenopausal BRCA1/2 mutation carriers. As a result, contralateral prophylactic mastectomy acceptance in patients with no such mutation is controversial. Contralateral prophylactic mastectomy can reduce the risk by up to 95%. Therefore, it is very important to evaluate the risk of contralateral breast cancer and to make appropriate surgical treatment. A review of risk factors for contralateral breast cancer and the benefits of contralateral prophylactic mastectomy in patients with unilateral breast cancer is presented.

Intraocular Pressure Sensor Based on a Contact Lens / 生物医学工程学杂志

Intraocular pressure detection has a great significance for understanding the status of eye health, prevention and treatment of diseases such as glaucoma. Traditional intraocular pressure detection needs to be held in the hospital. It is not only time-consuming to doctors and patients, but also difficult to achieve 24 hour-continuous detection. Microminiaturization of the intraocular pressure sensor and wearing it as a contact lens, which is convenient, comfortable and noninvasive, can solve this problem because the soft contact lens with an embedded micro fabricated strain gauge allows the measurement of changes in corneal curvature to correlate to variations of intraocular pressure. We fabricated a strain gauge using micro-electron mechanical systems, and integrated with the contact lens made of polydimethylsiloxane (PDMS) using injection molding. The experimental results showed that the sensitivity was 100. 7 µV/µm. When attached to the corneal surface, the average sensitivity of sensor response of intraocular pressure can be 125.8 µV/mm Hg under the ideal condition.

Multi-drug resistance and characteristic of integrons in Shigella spp. isolated from China / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate the characteristic of integrons and the relationship between integrons and antimicrobial resistance in Shigella spp.</p><p><b>METHODS</b>Ninety Shigella strains (83 S. flexneri and 7 S. sonnei) were isolated from the stools of patients in China. Susceptibility to 8 antimicrobials was tested for all isolated strains. PCR, RFLP and sequencing analysis of integrons were applied to all of them.</p><p><b>RESULTS</b>High prevalence of multi-drug resistance (95.6%) was identified. Of the isolates 79 (87.8%) carried integrase genes of class 1 integron (3.3%), class 2 integron (10.0%) or both (74.4%). No intI3 was detected in the tested isolates. The prevalence of intI2 was significantly higher in isolates with multi-drug resistance to at least 3 antibiotics than that in isolates with resistance to 2 and less antibiotics (P<0.05). Gene cassettes dfrA17-aadA5, dfrA12-orfF-aadA2 of class 1 integron and dfrA1-sat1-aadA1 of class 2 integron were identified.</p><p><b>CONCLUSION</b>The class 2 integron may play a role in the emergence of multi-drug resistance in Shigella spp.</p>

Analysis on mar gene mutation in mult-drug resistant Shigella / 中华微生物学和免疫学杂志

Objective To study the association of multi-drug resistance with mutations in mar gene in clinical isolates of Shigella.Methods Fifty-four clinical isolates of Shigella were collected.Susceptibility tests of tetracycline(TE),chloramphenieol(C),ampicillin(AM),cipr ofloxacin(CIP),and norfloxacin(NOR)were performed in a11 isolates.Hexane and cyclohexane were used to study the organic solvent tolerance of all clinical isolates.marOR genes of these strains were analyzed by potymerase chain reaction-single strand conformation polymorphism(PCR-SSCP)and were sequenced. Results Thirty-five multi-drug resistant strains were identified,and the rate of multi-drug resistance was 64.8%.Thirty-eight of 54 strains were tolerant to organic solvent,including 33 multi-drug resistance strains,3 drug resistant strains and 2 sensitive strains. marOR gene was found in all strains by PCR, and 5 multi-drug resistant strains,(14.29%)carrying marOR gene mutations in multi-drug resistant strains were found by SSCP analysis.DNA sequence analysis of marOR gene revealed that there was a 4 base deletion from base 1376 to 1379 in marO gene that resulted in frame-shift mutation.However,this deletion mutation didn;t exist in the standard strain S51250 and sensitive strains.There were 10 point mutations of marR gene in multi-drug resistant strains,2 of them resulting in amino acid changes:1752(G→A)Gly→ser,1854(T→c)Tyr→His.The rest mutations were all nonsense,and some of them occurred in sensitive strains or in many other strains.Conclusion The marO gene mutation may play an important role in the regulation of multi-drug resistance in Shigella spp.