Objective To study the efficacy of linezolid on gram positive bacterial infection in elderly patients and risk factors associated with thrombocytopenia.Methods A retrospective analysis of 50 elderly patients treated with intravenous linezolid for gram-positive bacterial infection from January 2008 to October 2010 was conducted.Clinical data and bacteriological responses were assessed.Efficacy of linezolid on infection and risk factors associated with thrombocytopenia in elderly patients were analyzed.Results The average duration of treatment was (13±2) d,the efficacy rate was 74 ％ and the bacteriological eradication rate was 69 ％ (18/26).Thrombocytopenia occurred in 24 patients during the treatment,and the average platelet count was significantly reduced compared with pretreatment[(146±87) 109/L vs.(239± 114) 109/L,t=3.888,P=0.000)].Thromhocytopenia was associated with the baseline platelet count and the mean time of linezolid treatment.Based on a Logistic regression analysis,the baseline platelet count ＜ 200 × 109/L was identified as the only significant risk factor for linezolid-associated thrombocytopenia in elderly patients (OR =0.244,95％CI:0.068-0.874,P=0.030).The mean platelet count was decreased significantly after 7 days of treatment,and decreased to the lowest value 1-2 days after the end of therapy.Conclusions Linezolid is effective and safe for the elderly with gram-positive bacterial infection,especially hospital acquired methicillin-resistant staphylococcus aureus infection.Linezolid has little effect on liver and renal function in elderly patients,but it can cause thrombocytopenia,which is associated with baseline platelet count and the mean time of linezolid treatment.Platelet counts should be monitored during treatment and measures should be taken to prevent hemorrhagic tendencies.

Objective To indentify the gene mutation of fibroblast growth factor receptor 3 (FGFR3) gene in a Chinese family with congenital achondroplasia (ACH). Methods The genomic DNA from 2 clinically diagnosed ACH patients and the other 4 members from the same family was prepared for PCR. The products of PCR were purified and then sequenced directly. Results Two patients with ACH in this family showed G-A transition mutation at nucleotide 1138 as heterozygotes. Conclusion The G-A transition mutation at nucleotide 1138 in transmembrane domain of FGFR3 gene seems to be the pathologic cause of this Chinese family with ACH.

Objective:To investigate the feasibility, safety and reasonable operation of nasointestinal canal indwelling guided by miniature system in severe neurosurgery patients, and compare its advantages and disadvantages with traditional blind insertion.Methods:A prospective randomized controlled trial design was used to select 128 critically ill patients in need of enteral nutrition support at the Department of Neurosurgery, the First Affiliated Hospital of Nanjing Medical University from March 2022 to October 2023 by convenient sampling method. They were divided into blind insertion group and visualization group by random number table method, with 64 cases in each group. Nasointestinal canal indwelling was performed in the blind insertion group by traditional blind insertion method, and in the visualization group, nasointestinal canal indwelling was performed by indentations guided by the miniature visualization system. The success rate of initial catheterization, the time of catheterization, complications, changes of vital signs during catheterization and changes of nutritional indexes after catheterization were evaluated in 2 groups.Results:In the blind insertion group, there were 35 males and 29 females, aged (59.44 ± 13.84) years old. In the visualization group, there were 41 males and 23 females, aged (58.28 ± 12.08) years old. The success rate of the first catheter placement in the visual group was 96.8% (62/64), higher than that in the blind group 82.8% (53/64), and the difference was statistically significant ( χ2=6.94, P<0.05). The catheter placement time of the visualization group was (20.08 ± 2.69) min, which was shorter than that of the blind insertion group (38.19 ± 3.79) min, and the difference between the two groups was statistically significant ( t=29.99, P<0.05). There was no significant difference in the incidence of complications, changes of vital signs during catheterization and the changes of nutritional indexes after catheterization between two groups (all P>0.05). Conclusions:Compared with traditional blind nasointestinal canal indwelling, nasointestinal canal indwelling guided by the miniature visualization system can improve the success rate of the first catheterization and shorten the catheterization time. Although there is no difference in the complication rate, changes in vital signs during catheterization and changes in nutritional indexes after catheterization, it is believed that with the continuous development and upgrading of this technology, it will further reflect the advantages of this technology, which is worthy of further clinical trials and application.