ABSTRACT:Objective To compare and analyze tip malposition of 2 central venous catheteri-zations in cancer patients.Methods Totally 1656 cancer patients received 1799 cases of peripheral-ly inserted central catheter(PICC)/conventional central venous catheter(CVC)were consecutively assessed by means of routine post-catheterization chest X-ray.The catheter with its tip strike and terminal position were confirmed individually.All tip malpositions were calculated.And the catheters with tip malpositions were readjusted and reevaluated.Results The failure rate in PICC group (2.68%)was significantly higher than that in CVC group(0.34%,P <0.01).Eighty three catheters(4.84%)were found tip malpositioned,in which 38 catheters(6.42%)were from PICC group and 45 ones(4.01%)from CVC group (P <0.01).The achievement ratio of readjustment for tip malposition in PICC group (71.1%)was much higher than that in CVC group (26.7%,P<0.01).Conclusion Compared with CVCs in cancer patients,the prevalence of tip malposition from PICCs was higher although the tip malpositions in PICCs were more likely to be corrected with readjustment.These findings suggest that tip position of PICC /CVC should be confirmed post-catheterization with chest x-ray.

ABSTRACT:Objective To compare and analyze tip malposition of 2 central venous catheteri-zations in cancer patients.Methods Totally 1656 cancer patients received 1799 cases of peripheral-ly inserted central catheter(PICC)/conventional central venous catheter(CVC)were consecutively assessed by means of routine post-catheterization chest X-ray.The catheter with its tip strike and terminal position were confirmed individually.All tip malpositions were calculated.And the catheters with tip malpositions were readjusted and reevaluated.Results The failure rate in PICC group (2.68%)was significantly higher than that in CVC group(0.34%,P <0.01).Eighty three catheters(4.84%)were found tip malpositioned,in which 38 catheters(6.42%)were from PICC group and 45 ones(4.01%)from CVC group (P <0.01).The achievement ratio of readjustment for tip malposition in PICC group (71.1%)was much higher than that in CVC group (26.7%,P<0.01).Conclusion Compared with CVCs in cancer patients,the prevalence of tip malposition from PICCs was higher although the tip malpositions in PICCs were more likely to be corrected with readjustment.These findings suggest that tip position of PICC /CVC should be confirmed post-catheterization with chest x-ray.

To improve collagen production by recombinant Pichia pastoris, we applied Placket-Burman and Box-Behnken design to optimize the fermentation medium. Through Placket-Burman design, three variables in the medium (concentration of yeast extract, peptone and glycerol) were selected for having significant effect on cell dry weight. Through Box-Behnken design regression coefficients analysis, a secondary degree polynomial equation was established, and the optimum levels of the three variables were yeast extract 1.13%, peptone 1.61% and glycerol 0.86%. During the growth period, an average cell dry weight of 4.41 g/L was obtained after 12 h fermentation, increased by 26%. Through high density fermentation, the production of recombinant human collagen (Ⅲ) was up to 4.71 g/L in 22 L fermentor. The recombinant human collagen (Ⅲ) exhibited good results to repair acetic acid induced gastric ulcer in rats.

Objective: To evaluate the residual radioactivity after ¹³¹I treatment in postoperative inpatients with differentiated thyroid carcinoma (DTC) using service robot in nuclear medicine ward, and assess the time for patients to be released from isolation. Methods: From September 2017 to June 2018, 297 patients (94 males, 203 females, age: 19-80 years) with DTC who underwent ¹³¹I treatment after surgery were included. According to the purpose of treatment and the prescription dosage of ¹³¹I, patients were divided into 8 groups: 4 groups accepted ¹³¹I remnant ablation therapy (RAT) with different dosages, which were 3 700 MBq (RAT1, n=34), 4 440 MBq (RAT2, n=122), 5 550 MBq (RAT3, n=81) and 7 400 MBq (RAT4, n=27), respectively; 4 groups had ¹³¹I treatment for recurrent/metastatic lesions (RMLT), and the dosages were 3 700 MBq (n=1), 4 440 MBq (n=2), 5 550 MBq (n=14) and 7 400 MBq (n=16). At 4, 24, 48 and 72 h after ¹³¹I administration, the dose equivalent rates at 2 cm away from the patient′s neck and at 1 m away from the body were measured by the robot designed for nuclear medicine ward. Kruskal-Wallis rank sum test and Mann-Whitney U test were used to analyze the data. Results: Neck dose equivalent rates for patients with RAT at different time points (4, 24, 48 and 72 h) after ¹³¹I administration were significantly different among 4 groups (H values: 20.889-46.410, all P<0.05), as well as the body dose equivalent rates (H values: 27.181-35.497, all P<0.05). The neck dose equivalent rates at 24, 48 and 72 h after ¹³¹I administration were statistically different between group 3 and 4 for patients with RMLT (z values: 2.328-3.076, all P<0.05; data in group 1 and 2 were too limited to be compared), while there was no statistical difference for the body dose equivalent rates (z values: 0.333-1.621, all P>0.05). The radioactivity retention in patients decreased rapidly within 24 h, then slowed down gradually and became extremely low at 72 h. At 72 h after ¹³¹I administration, 96.6%(255/264) patients with RAT and 100%(33/33) patients with RMLT were lower than 23.3 μSv/h, which meant the patients could be discharged from hospitalization. Conclusions Nuclear medicine ward service robots may dynamically measure residual radioactivity in DTC patients who take ¹³¹I treatment, providing individualized isolation solutions.