[Preparation and characterization of paclitaxel microspheres in situ gel and its antitumor efficacy by local injection]

OBJECTIVE

The current difficulties in the treatment of tumor include repeated administration and high recurrence rate after tumor resection. In order to reduce the number of doses, avoid side effects of chemotherapeutic drugs, suppress tumor growth and delay tumor recurrence after surgery, a temperature-sensitive in situ gel with paclitaxel microspheres (PTX/M gel) was prepared. PTX/M gel was administered by intratumoral injection once a month.

METHODS

First of all, paclitaxel microspheres (PTX/M) were prepared by emulsion solvent evaporation method. A laser particle size distribution analyzer was used to investigate the size, distribution, specific surface area of microspheres. Paclitaxel content was determined by high performance liquid chromatography (HPLC). Then encapsulation efficiency of paclitaxel was calculated and in vitro release characteristics were studied. Secondly, PTX/M gel was prepared by cold dissolution method. The phase transition temperature, elastic modulus, dissolution curve, correlation between dissolution and release were measured. Finally, U87 MG and 4T1 subcutaneous tumor models were established respectively to study the efficacy of PTX/M gel in suppressing tumor growth and delaying tumor recurrence after surgery.

RESULTS

The median diameter of the selected PTX/M was (32.24±1.09) μm, the specific surface area was (206.61±10.23) m²/kg, the encapsulation efficiency was 85.29%±1.34%, and the cumulative release percentage of paclitaxel from PTX/M was 33.56%±3.33% in one month. Phase transition temperature of PTX/M gel was 33 °C. The elastic modulus of PTX/M gel at 25 °C and 37 °C were 4.2×103 Pa and 18×103 Pa, respectively. The gel could stay in the body for up to 48 hours. It could be seen from the results of animal experiments that were compared with the saline group and the Taxol group, and the tumor-bearing mice of the PTX/M gel group had the slowest tumor growth (P<0.05). Similarly, in the tumor recurrence experiments, the mice of PTX/M gel group had the latest tumor recurrence after surgery.

CONCLUSION

As a local sustained-release preparation, PTX/M gel can effectively suppress tumor growth and delay postoperative recurrence of tumors. It has potential advantages in tumor treatment.

[Quantitative evaluation of the relationship between femoral trochlear dysplasia and the degeneration of the patellofemoral cartilage by using T2mapping]

Objective: To evaluate the relationship between the femoral trochlear dysplasia(FTD) and the degeneration of the patellofemoral cartilage by using MR T2mapping technique. Methods: Sixty two subjects with FTD(aged 18-45 years) were enrolled in Tianjin First Center Hospital from January 2016 to December 2017,the controls which both age and gender were matched.T2mapping scan were aquired for each subject and control. Compare the differences of the T2mapping values for each area between subjects and controls, and compare Dejour types of femoral trochlear in different age groups, respectively. Results: The T2mapping value of subjects was significant lower than controls: the superficial-femoral-lateral layer (sFL) (P=0.000) and the superficial-patella-lateral layer (sPL) (P=0.009). In the group of age less than 30 years, the T2mapping value of subjects was significant lower than controls:sFL (P=0.001) and sPL (P=0.015). In group of age greater than 30 years, the T2mapping value of subjects was significant lower than controls: sFL (P=0.035). In difference Dejour types of FTD, the T2mapping value of type B-D was lowest in sFL(P=0.014),sPL(P=0.000), the superficial-patella-medial layer (sPM) (P=0.020) and the the T2mapping value of type B-D was highest in the deep-femoral-medial layer (dFM) (P=0.006). The difference was statistically significant, P<0.05. Conclusion: The FTD might cause the early degeneration of patellofemoral cartilage, which significantly appear in the young age; The type B-D of FTD is more likely to cause the wider range of superficial cartilage injure and involved some part of deep layer; the injure shows dehydration change in superficial cartilage and edema in deep layer.

Protective humoral immunity in guinea pigs induced by PCV2 virus-like particles displaying the B cell linear epitope (228QQITDA233) of PPV1

Although PCV2 infections generally cause mild disease in pigs, concurrent co-infections with other pathogens can damage the immune system and cause more severe diseases, collectively termed porcine circovirus associated diseases (PCVAD). Involvement of porcine parvovirus (PPV, a common cause of reproductive failure in naïve dams) in PCVAD caused by PCV2, has been reported. As this co-infection can be difficult to eliminate, there is a critical need to develop an effective vaccine to protect against PPV or synergistic effects of PCV2 and PPV under field conditions. In this study, we designed chimeric PCV2 virus-like particles (cVLPs) displaying a B-cell epitope derived from PPV1 structural protein around the surface of the 2-fold axes of PCV2 VLPs, based on 3D-structure analysis of the PCV2 capsid. The cVLPs were successfully prepared, verified by transmission electron microscopy and chromatography, with robust antibody titers against PCV2 and PPV1 produced in mice and guinea pigs. In addition, in guinea pigs challenged with 10⁶ TCID₅₀ PCV2, cVLPs conferred more effective immune protection (based on viral load) than a commercial PCV2 vaccine. Finally, antibody responses and immune protection against PPV were also evaluated. In guinea pigs vaccinated with cVLPs, although PPV antibodies detected by a hemagglutination inhibition (HI) assay appeared later after vaccination in the PCV2 cVLPs group than in the commercial PPV vaccine group, there were fewer PPV genomic DNA copies in the PCV2 cVLPs group than in a PBS group. In conclusion, guinea pigs vaccinated with cVLPs developed effective protective immunity against PCV2 challenge, with some protective immunity against PPV. This study provided valuable research data to pursue molecular design of chimeric epitopes PCV2 VLPs.

CD5-negative chronic lymphocytic leukemia/small lymphocytic lymphoma in a patient with gastrointestinal mantle cell lymphoma: an unusual case report

Richter’s syndrome, the development of high-grade non-Hodgkin lymphoma in patients with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), may be triggered by viral infections (eg, Epstein–Barr virus infection). Herein, we report an unusual case of CD5-negative CLL/SLL patient with gastrointestinal mantle cell lymphoma (MCL) and hepatitis B virus infection. CLL/SLL was diagnosed based on lymph node immunohistochemistry and bone marrow pathology. This patient was treated with seven cycles of multi-agent chemotherapy. During treatment, the hepatitis B viruses were activated. Then, after 20 months of antiviral treatment with entecavir, he developed abdominal discomfort and abdominal lymphadenopathy and was diagnosed with MCL based on intestinal biopsy. This work indicates that the hepatitis B virus in patients with CLL/SLL may accelerate the progress or transformation to MCL.

Raddeanin A down-regulates androgen receptor and its splice variants in prostate cancer

Castration-resistant progression of prostate cancer is a major cause of prostate cancer mortality, and increased expression and activity of the full-length and the splice variants of androgen receptor (AR) have been indicated to drive castration resistance. Consequently, there is an urgent need to develop agents that can target both the full-length and the splice variants of AR for more effective treatment of prostate cancer. In the present study, we showed that raddeanin A (RA), an oleanane-type triterpenoid saponin, suppresses the transcriptional activities of both the full-length and the splice variants of AR. This is attributable to their decreased expression as a result of RA induction of proteasome-mediated degradation and inhibition of the transcription of the AR gene. We further showed the potential of using RA to enhance the growth inhibitory efficacy of docetaxel, the first-line chemotherapy for prostate cancer. This study identifies RA as a new agent to target both the full-length and the splice variants of AR and provides a rationale for further developing RA for prostate cancer treatment.

Self-Assembled Chiral Nanoparticle Superstructures and Identification of Their Collective Optical Activity from Ligand Asymmetry

The spontaneous self-assembly of chiral nanoparticles (NPs) into stationary fabrication has garnered great interest in technique investigation and science advancement due to its expected apparent properties via orderly collective behaviors. However, this kind of characterization of assembled nanoparticles superstructure (NPS) is rarely reported and is distinguished with monodispersed chiral NPs. In this work, we used l-cysteine (Cys) as the chiral molecule in the form of functional surfactant, which had capped CdS/CdTe NPs and was treated as a linkage bridge for constructing orderly assembled NPS. Among the circular dichrosim (CD) phenomenon, Cys ligands exhibit related changes in CD absorption, while whole-molecule solution was used for treatment in different pH-controlling procedures. Synthesized chiral NPs are organized into ordered rod-shaped NPS during the spontaneous self-assembly process, and the CD response of NPS is monitored in different cultivating times; it showed a persuasive response appears in sum frequency generation (SFG) spectroscopy. Both experimental works and theory calculation convey that the ordered stacking of chiral stabilizer and the chirality of NPS, which are identified from chiral molecular status and their collective optical activity, originated from ligand asymmetry.

[Evaluation of bioceramic putty repairment in primary molars pulpotomy]

OBJECTIVE

To evaluate the clinical characteristics and effectiveness of bioceramic putty repairment (iroot BP Plus) used as pulp capping agents on pulpotomy in primary molars.

METHODS

Forty primary molars were treated by pulpotomy with bioceramic putty repairmen as the pulp capping agents at the Third Clinical Division of Peking University School and Hospital of Stomatology, from September 2016 to September 2017. The children who were followed up over one year were selected as the subjects of this study. The teeth were checked clinically and radiographically during fixed intervals, and classified into one of five outcomes: N, H, P₀, P_X, P_Y. N, absence of clinical symptoms, and absence of apical radiolucency; H, absence of clinical symptoms, and nonpathologic radiographic change present; P₀, absence of clinical symptoms, and pathologic change present, no need for treatment; P_X, present or absence of clinical symptoms, pathologic change present treatment or extract immediately; P_Y, premature loss of deciduous tooth. Molars classified into N and H were regarded as successful, classified into P₀, P_X and P_Y were regarded as failed.

RESULTS

Followed up for 12-24 months (the average follow up time was 16months), thirty four children were finally included, aged from 3.1 years to 8.5 yaers (the average age was 4.3 years), forty primary molars were included. Thirty four primary molars were included into N group, with absence of clinical symptoms, absence of apical radiolucency. Two molars were included into H group with physiological root absorption. One molar was included into P₀group with absence of clinical symptoms butinternal absorption of the root. Three molars were included into P_X group, with gingival fistula and apical radiolucency. None was included into P_Y group. Thirty six teeth got successful treatment, four molars failed. One year success rate of pulpotomy of primary molars using bioceramic putty repairment was 95%.

CONCLUSION

Current evidence suggests that bioceramic putty repairment as a pulpotomy medicament showed satisfied clinical and radiographic result in pulpotomy of primary molars. Bioceramic putty repairment is an acceptable material when used in pulpotomy of primary molars.

Inhibition of Abl or Src tyrosine kinase decreased porcine circovirus type 2 production in PK15 cells

Porcine circovirus type 2 (PCV2) causes huge economic losses in the global swine industry and has a complex and poorly understood virus-host interaction mechanism. We reported that the C-terminal of the capsid protein of all PCV2 isolates shared a strictly conserved PXXP motif that may interact with SH3 domain-containing tyrosine kinases; however, its roles in PCV2 cell entry and replication remain unknown. In this study, we determined that mRNA levels of two SH3 domain-containing tyrosine kinases family (Abl and Src) had distinct profiles (wild-type and PXXP-mutated) during PCV2 infections of PK15 cells. Therefore, we hypothesized that activities of tyrosine kinases (Abl and Fyn) in PK15 cells may be hijacked by PCV2 via its PXXP motif of the Cap, to favor virus replication. Specific inhibitors PP2 of Lck/Fyn and STI-571 of Abl family kinases decreased viral production through suppression of DNA and Cap synthesis at the replication stage. However, based on indirect immunofluorescence assay (IFA), entry of PCV2 virus-like particles (VLPs) into PK15 cells was not altered. Elucidating mechanisms of PCV2-host interactions should provide new insights for development of new compounds to prevent or reduce PCV2 infections.

Forecasting and predicting intussusception in children younger than 48 months in Suzhou using a seasonal autoregressive integrated moving average model

OBJECTIVE

The aims of this study were to highlight some epidemiological aspects of intussusception cases younger than 48 months and to develop a forecasting model for the occurrence of intussusception in children younger than 48 months in Suzhou.

DESIGN

A retrospective study of intussusception cases that occurred between January 2007 and December 2017.

SETTING

Retrospective chart reviews of intussusception paediatric patients in a large Children's hospital in South-East China were performed.

PARTICIPANTS

The hospital records of 13 887 intussusception cases in patients younger than 48 months were included in this study.

INTERVENTIONS

The modelling process was conducted using the appropriate module in SPSS V.23.0.

METHODS

The Box-Jenkins approach was used to fit a seasonal autoregressive integrated moving average (ARIMA) model to the monthly recorded intussusception cases in patients younger than 48 months in Suzhou from 2007 to 2016.

RESULTS

Epidemiological analysis revealed that intussusception younger than 48 months was reported continuously throughout the year, with peaks in the late spring and early summer months. The most affected age group was younger than 36 months. The time-series analysis showed that an ARIMA (1,0,1 1,1,1)₁₂ model offered the best fit for surveillance data of intussusception younger than 48 months. This model was used to predict intussusception younger than 48 months for the year 2017, and the fitted data showed considerable agreement with the actual data.

CONCLUSION

ARIMA models are useful for monitoring intussusception in patients younger than 48 months and provide an estimate of the variability to be expected in future cases in Suzhou. The models are helpful for predicting intussusception cases in Suzhou and could be useful for developing early warning systems. They may also play a key role in early detection, timely treatment and prevention of serious complications in cases of intussusception.