Objective To evaluate the mutagenicity of hydrolysate of Meretrix meretrix Linnaeus soft tissue, so as to provide experimental basis for its exploitation.Methods Three mutagenicity tests were used to evaluate the mutagenic effects, including Ames test, CHL chromosome aberration assay and bone marrow micronucleus assay in mice.Results In Ames test, the revertant colonies numbers in each group were twice less than the numbers of spontaneous revertant colo-nies, five bacterial strains showed negative results with or without S9 activation, and the result of Ames test was negative. The CHL chromosome aberration assay and bone marrow micronucleus assay showed that the chromosome aberration rate and micronucleus rate of each dose group showed no significant difference compared with the negative control group, respec-tively ( P>0.05) .Conclusions Under this condition, the results show that all of the Ames test, chromosome aberration assay and bone marrow micronucleus assay are negative, and no mutagenicity is observed in the hydrolysate of Meretrix mer-etrix Linnaeus soft tissue.

Objective To observe hepatocellular apoptosis and inflammatory cytokines expression and their mechanisms after paraquat poisoning in rat.Methods Forty Wistar rats were divided into control group (n =8) and model group (n =32) by random number table.Rats in model group were intraperitoneally injected with 30 mg/kg 20％ paraquat concentrate,while those in control group were injected with normal saline.0.5,1,3,7 days after reproduction of the model,8 rats were sacrificed,and blood was collected from inferior vena cava and hepatic tissue was harvested.The serum levels of interleukin-1β (IL-1 β) and tumor necrosis factor-α (TNF-α) were determined by enzyme-linked immunosorbent assay (ELISA).The mRNA expressions of IL-1β,TNF-α,inducible nitric oxide synthase (iNOS) and p53 were determined by reverse transcription-polymerase chain reaction (RT-PCR).Cysteine-containing aspartate-specific proteases (caspase-3,-8,-9,-12) activity in hepatic tissue was determined on the 3rd day with chromogenic substrate method.The liver histopathological changes were observed after hematoxylin-eosin (HE) staining.Results In model group,hepatic tissue showed extensive necrosis with inflammatory cell infiltration in time dependant manner.Serum IL-1β and TNF-α levels were significantly higher in model group half a day after reproduction than those in control group [IL-1β (ng/L):220.13 ± 69.74 vs.0.14 ± 0.03,TNF-α (ng/L):102.66 ± 26.43 vs.0.16 ± 0.02,P＜ 0.01 and P＜0.05],and peaked on the 3rd day and 1st day [IL-1β:(423.72 ± 153.11) ng/L,TNF-α:(690.35 ± 229.64) ng/L].They then decreased gradually,but were still significantly higher than those in control group on the 7th day [IL-1 β:(357.47 ± 87.28) ng/L,TNF-α:(12.39 ± 5.06) ng/L,both P＜0.05].The contents of IL-1β,TNF-α and iNOS mRNA expressions in hepatic tissue were significantly higher than those in control group,and the highest values were seen on the 1st day,the 1st day,and the 3rd day [IL-1β mRNA (gray value):1.569 ± 0.057 vs.0.123 ± 0.016,TNF-α mRNA (gray value):0.683 ± 0.077 vs.0.261 ± 0.025,iNOS mRNA (gray value):3.259 ± 0.135 vs.0.002 ±0.001,P＜0.05 or P＜0.01].There was no difference in p53 mRNA expression between model group and control group at early stage,and both of them showed low expression,and p53 mRNA expression was significantly higher in model group on the 7th day (gray value:2.959 ± 0.086 vs.0.263 ± 0.032,P＜0.01).In model group,caspase activity (pmol/mg) in liver tissue were significantly higher on the 3rd day than those in control group (caspase-3:857.25 ± 309.26 vs.169.73 ± 48.21,caspase-8:199.18 ± 61.41 vs.32.26 ± 11.09,caspase-9:321.62 ± 80.73 vs.90.38 ± 29.76,caspase-12:413.13 ± 89.77 vs.26.73 ± 9.86,all P＜0.01).Conclusion Paraquat can cause acute liver injury in rats,with caspase-3,-8,-9,-12 activities markedly enhanced,and liver injury may be associated with an early high expression of TNF-α,iNOS and p53 gene.

Objective To study the influencing factors and quality control of chromosome preparation during chromosome aberration test in vitro,and to summarize and analyze the method and key points of successful preparation of chromosome specimens in vitro. Methods Chinese hamster lung cells(CHL)were used for cell culture and chromosome preparation. Mitomycin and cyclophosphamide were used as positive mutagens. After routine hypotonic treatment,fixation, and squash preparation, finally, to read the film under the microscope. Results The CHL chromosome aberration test showed that both the chromosome aberration rates of mitomycin- and cyclophosphamide-treated cells were significantly increased(>20%),while the aberration rates in the negative control group were less than 5%, either with and without metabolic activation. The success rate was high and the prepared chromosomes were well dispersed with a moderate length. Conclusions Many factors can affect the specimen preparation in chromosome aberration test. Every step is very important,and it should be strictly following the operating procedures. It is of importance to grasp the principle of each step and to operate carefully,patiently and scientifically in order to prepare good specimens.

Maximum a Posteriori (MAP) method has been widely applied to the ill-posed problem of image reconstruction. The choice of prior is the crucial point on MAP methods. However, the most conventional priors will lead to a blurring of the whole image or cause ladder-like artifacts. We therefore proposed a Tsallis entropy-based prior for positron emission tomography (PET) iterative reconstruction in MAP framework. The method uses a Tsallis entropy-based prior to eliminate the uncertainty between prior information and the estimated images. We tested this method in the phantom image, compared it with the traditional prior methods. the results showed that the proposed algorithm could suppress noise and obtain better reconstructed image quality.
Algorithms ; Artifacts ; Entropy ; Image Processing, Computer-Assisted ; methods ; Phantoms, Imaging ; Positron-Emission Tomography ; methods

Objective: To evaluate the clinical effect of multiple osteotomies combined with distraction osteogenesis in the treatment of non-syndromic scaphocephaly infants and young children. Methods: Clinical records of 8 non-syndromic scaphocephaly patients, during January 2017 to October 2018, from the Department of Burn and Plastic Surgery, Children′s Hospital of Nanjing Medical University, were retrospectively analyzed. There were 3 males and 5 females, aged from 3 to 28 months, with an average of 13 months. Among them, 4 cases were typical scaphocephaly, 2 cases were anterior scaphocephaly and 2 cases were posterior scaphocephaly. According to the subtypes of scaphocephaly, different osteotomy methods and distraction directions were designed. The cranial vault was osteotomized by piezosurgery osteotomy in a multiple way. The dura did not separate from cranial flap. The internal distractors were installed subsequently. After a mean latency period of 5 days, the devices were activated at a rate of 0.4-0.6 mm/d. Distractor was extended twice a day. After 10-15 days activation period and 6 months consolidation, all the distractors were removed. Three-dimensional CT scans were performed before and after operation to measure the anteroposterior and bitemporal diameters, so as to calculate the cranial index. Results: Follow-up ranged from 6 to 14 months (average, 10 months). The average anteroposterior length of 8 children was(158.2±12.9) mm before operation, and (145.5±14.2) mm after operation, which was shortened(12.6±3.4) mm. Bitemporal diameters was(99.6±8.6) mm preoperatively and(113.9±7.5) mm postoperatively, which was widened (14.2±2.8) mm. Preoperative and postoperative cranial index was 63.2 and 78.3, respectively. The scaphocephalic head shape was significantly improved in all patients. There was no serious complications such as skull necrosis or intracranial infection. Conclusions Different types of multiple osteotomy combined with distraction osteogenesis are useful to correct various scaphocephaly of infants and children, by improving skull shape and cranial index.

Objective: To evaluate the effect of three-dimensional Z-shaped osteotomy with cranium distraction osteogenesis for unilateral lambdoid synostosis. Methods: Imaging the skull as a cuboid, we designed the affected lambdoid suture as the middle line of letter Z, the osteotomy line paralleling to the sagittal suture or extending downward posterior cranial fossa as the two horizontal lines of Z to obtain the three-dimensional Z-shaped osteotomy lines. Two or three distraction devices were installed after removing the cranial bone at the premature fused suture with a width of 2.0-2.5 cm. Since the 5th day after operation, distraction was performed at the rate of 0.6 mm each day, twice a day, until the distraction distance reached 2.0-4.5 cm. Finally, we removed the distractors after fixation for three months. Results: Eleven cases of unilateral lambdoid synostosis were treated successfully. No infection or bleeding happened except for one case with distractor entrance scalp infection. No complications, including the fixed screws displacement, penetrating the cranium and the dura mater or distraction devices retracting, occurred. During a mean follow-up period of 24 months (5 to 36 months), all patients were satisfied with the cosmetic and functional result. Conclusions Three-dimensional Z-shaped osteotomy with cranium distraction osteogenesis can not only extend upward to raise the cranial height, but also lengthen backward to singularize the occipital carina, forming a well-pleasing occipitalia. Z shape stabilizes the whole plate, making the separated cranial bones not easy to retract. Therefore, using this procedure is effective and mini-invasive, and especially suitable for young infant.

Objective:To investigate the safety and efficacy of sirolimus through the change in platelet counts during the sirolimus therapy on Kasaback-Merritt phenomenon(KMP).Methods:Four patients were treated in Nanjing Children Hospital between Jaunary 2017 and June 2019 were enrolled in the study, including two males and two females. Their age was ranged from two days to three months. They all presented with huge mass located in neck or retroperitoneal and thrombocytopenia, hypofibrinogenemia. Their coagulation could not be improved by surgery or palate transfusion or steroids. They were all diagnosed as Kaposiform hemangioendothelioma(KHE) with KMP according to the biopsy, coagulation index and CT. Sirolimus were administered with 0.1 mg -1·kg -1·d -1 or 0.8 mg/m 2, twice daily. Subsequent dose was adjusted to maintain the trough level between 10-15 ng/ml.Steroids were weaned gradually. Blood accounts were measured following the sirolimus administration. Results:All the four patients got improvement in platelet counts. Three patients went through a significant decreasing of palate counts after adding sirolimus for about 1-4 days. Two lesions prompted improvement with smaller size, lighter color and softer texture without complete regression. Two patients had elevated liver enzymes and/or interstitial pneumonia. One recovered while the other died of severe pneumonia with dyspnea. All the palate counts of survived patients remained in normal level in the following one year.Conclusions:Sirolimus is an effective method in treating KMP and stabilizing platelet counts. However, it can not cure hemangioendothelioma.

Objective:To investigate the safety and efficacy of sirolimus through the change in platelet counts during the sirolimus therapy on Kasaback-Merritt phenomenon(KMP).Methods:Four patients were treated in Nanjing Children Hospital between Jaunary 2017 and June 2019 were enrolled in the study, including two males and two females. Their age was ranged from two days to three months. They all presented with huge mass located in neck or retroperitoneal and thrombocytopenia, hypofibrinogenemia. Their coagulation could not be improved by surgery or palate transfusion or steroids. They were all diagnosed as Kaposiform hemangioendothelioma(KHE) with KMP according to the biopsy, coagulation index and CT. Sirolimus were administered with 0.1 mg -1·kg -1·d -1 or 0.8 mg/m 2, twice daily. Subsequent dose was adjusted to maintain the trough level between 10-15 ng/ml.Steroids were weaned gradually. Blood accounts were measured following the sirolimus administration. Results:All the four patients got improvement in platelet counts. Three patients went through a significant decreasing of palate counts after adding sirolimus for about 1-4 days. Two lesions prompted improvement with smaller size, lighter color and softer texture without complete regression. Two patients had elevated liver enzymes and/or interstitial pneumonia. One recovered while the other died of severe pneumonia with dyspnea. All the palate counts of survived patients remained in normal level in the following one year.Conclusions:Sirolimus is an effective method in treating KMP and stabilizing platelet counts. However, it can not cure hemangioendothelioma.

OBJECTIVE We hypothesized that unstable ventilatory control(high loop gain, LG) could predict the short-term efficacy of positive airway pressure therapy in patients with obstructive sleep apnea(OSA). METHODS 42 adult patients with OSA, M/F=39/3, were studied. The stability of the ventilatory control system(LG) was quantified by fitting a simplified mathematical model to the spontaneous ventilatory pattern obtained via polysomnography. LG, pulmonary function test results, and other PSG parameters were analyzed in patients who had post-treatment AHI≥10 events/hr(non-responders) using auto-positive airway pressure therapy. RESULTS The subjects aged(40±8) years, apnea-hypopnea index(AHI) were 68.2[42.9,81.0]events/hr). Nine patients(34.6％) were non-responders. Twenty pat ients(47.6％) had residual AHI＜5 events/hr. Loop gain and pre-treatment mixed apnea index were higher in the non-responders versus responders(0.74 [0.62, 0.82] vs 0.49[0.37, 0.77], P =0.035) and(11.0[4.3, 22.9] vs 2.0[0.2, 5.3], P =0.004). In the 26 patients with LG＞0.6, nine(34.9％) had posttreatment 5 events/hr≤AHI＜10 events/hr. And all of the non-responders had LG(n=9, 34.9％). The difference was signif icant between the LG＞0.6 a nd LG＜0.6 group(P =0.007). CONCLUSION Loop gain and mixed apnea index was higher in patients with residual AHI＞10 events/hr after short-term auto-PAP therapy. Ventilatory control stability evaluation might have predictive value for PAP treatment efficacy in OSA patients.

Objective: To investigate the treatment of nasal deformity in patients with unicoronal craniosynostosis. Methods: In patients over 6 months old, the nasal bones were wedge-removed without fixation. The management of all patients with unicoronal craniosynostosis was distraction osteogenesis of pedicled unilateral frontal bone flap. Results: Postoperative extended distance of the frontal bone was 28—41 mm (mean, 35.4 mm). After extension, three-dimensional reconstruction of cranial CT was carried out, which showed that CVAI was 0.8—1.2 (mean, 0.98), tending to normal. After discharge, dynamic cranial braces were put on for 1 year. Postoperatively, the children were followed up for 8—36 months (mean, 28 months). The shape and nasal deformity of all children were improved compared with those before surgery. Conclusions Nasal wedge resection should be used to correct nasal deformity in children over 6 months with unicoronal craniosynostosis.