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Multidrug resistance is a major obstacle to successful chemotherapy of cancer. To overcome multidrug resistance, our research is to develop new liposome and nanomicelle delivery systems. Investigations are focusing on certain aspects, including resistant cancer cell membranes, cancer stem cells, mitochondria, apoptosis genes, vasculogenic mimicry and heterogeneity of cancer cells. Evaluations have been performed on cancer cells, cancer spheroids and cancer animal models. These nanoscale formulations demonstrated an enhanced chemotherapy efficacy in resistant cancer and cancer stem cells in vitro and in vivo.

Human leukocyte antigen (HLA) class II molecule is an integral component of the immune response on which the majority of host genetic studies have concentrated. Many different HLA-II alleles have been demonstrated to play roles in HBV infection. PCR-SSOP methods were applied to determine the HLA-DRB1 genotypes of 769 unrelated healthy individuals from Han Chinese of Northeast China. The frequencies of HLA-DRB1*09 in hepatitis B virus (HBV)-infected subjects were higher compared to those in the control group. Frequencies of HLA-DRB1*04 and *13 in the HBV-infected group were significantly lower compared to those in the healthy control group. Frequencies of HLA-DRB1*12 in the cirrhosis and liver cancer groups were significantly higher than those in the chronic hepatitis B (CHB) patients. The frequency of LA-DRB1*03 in the CHB patient group was significantly higher compared to that in the asymptomatic hepatitis B carrier patients. The above results suggest that the host HLA-II gene is an important factor in the determination of the outcome of HBV infection.

Aim: To take fundus examination in the preterm neonates to observe the common diseases and report the outcomes in a neonatal intensive care unit (NICU) in Guangzhou between May 2008 and May 2011., Methods: Fundus examinations were performed with Retcam II in 957 prematures., Results: There were 957 prematures in this study, including 666 males and 291 females, 2 triple births, 152 twins and 803 singletons. During the three years, 86 infants with any stage retinopathy of prematurity (ROP) (9.0%), 123 infants with retinal hemorrhage(12.9%), 10 infants with neonatal fundual jaundice(1.0%) and 3 babies with congenital choroidal coloboma (0.3%) were found., Conclusion: Early detection and prompt treatment of ocular disorders in neonates is important to avoid lifelong visual impairment. Examination of the eyes should be performed in the newborn period and at all well-child visits.

Objective: To evaluate the incidence and risk factors for severe retinopathy of prematurity (ROP) in preterm infants., Methods: Between May, 2008 and May, 2011, a total of 957 preterm infants at 4-6 weeks of chronological age or 32 weeks of postmenstrual age underwent retinal evaluation by RetCamII in our center, and the data of infants with ROP in any stage were analyzed., Results: Among the 957 preterm infants, we found 86 (8.99%) infants to have ROP in different stages, including 60 (6.27%) with mild ROP and 26 (2.72%) with severe ROP. The birth weight and gestational age of the infants with severe ROP averaged 1 420.40∓328.64 g and 29.88∓1.67 weeks, as compared to 1 593.28∓339.30 g and 31.78∓2.53 weeks in those with mild ROP, respectively, showing a significant difference between the two groups (P<0.005). The significant variables for severe ROP included gestational age (P=0.001), birth weight (P=0.035), 1 min Apgar score (P=0.001), 5 min Apgar score (P=0.005), number of blood transfusions (P=0.032), and the presence of apnea (P=0.04) and retinal hemorrhage (P=0.000). Gestational age and retinal hemorrhage were the independent risk factors for severe ROP (OR=0.353, 95%CI 0.163-0.763, P=0.008; OR=26.133, 95%CI 3.042-224.501, P=0.035)., Conclusion: Severe ROP tends to have a decreasing incidence and occurs more often in more mature preterm infants. The affected infants have the characteristics of the first epidemics. Gestational age and retinal hemorrhage are independent predictive factors for severe ROP.

Background: Multidrug resistance (MDR) of cancers can be circumvented by inducing programmed cell death, which is known as apoptosis. Mitochondria play a crucial role in apoptosis. Mitochondria-specific therapy would provide an efficient strategy for treating resistant cancers., Design and Methods: A strategy was proposed here to overcome MDR by designing cancer mitochondria-specific drug-loaded liposomes, namely, antiresistant epirubicin mitosomes, aimed at treating resistant leukemia by targeting mitochondria. Evaluations were performed on human chronic leukemia K562, MDR K562/ADR cells, and female BALB/c nude mice xenografted with MDR K562/ADR cells. The liposomes were characterized through assays of cytotoxicity, mitochondrial targeting, caspase-9 and caspase-3, antitumor activities, and TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling) analysis., Results: The average size of antiresistant epirubicin mitosomes was in the range of 105-115 nm. Antiresistant epirubicin mitosomes were effective in inhibiting proliferation of MDR K562/ADR cells in vitro and selectively accumulated into the mitochondria. Caspase-9 and caspase-3 activity was increased after applying antiresistant epirubicin mitosomes. In xenografted resistant MDR K562/ADR tumor in nude mice, antiresistant tumor effect of antiresistant epirubicin mitosomes was evidently observed. Apoptotic inducing effects by antiresistant epirubicin mitosomes were noticeably evidenced via mitochondrial pathway., Conclusions: Antiresistant epirubicin mitosomes had significant inhibitory effect against resistant leukemia in vitro and in vivo, hence providing a promising strategy for improving therapeutic efficacy in resistant human leukemia.

Supercooling point (SCP) of female adults of Corythucha ciliata was significantly lower than that of male adults, with an average being -11.49 degrees C and -9.54 degrees C, respectively. Low temperature survival of adults of different ages indicated that there were differences in cold survival ability among age groups of adults. Nonlinear regression analysis found that the response of C. ciliata adults to exposure time under different low temperature regimes (above -5 degrees C) was best fitted by a logistic equation. Both low temperature and exposure time had significant effects on mortality of adults. Temperatures above 5 degrees C did not prevent C. ciliata adults from surviving. C. ciliata was shown to be a freeze-intolerant but chill-tolerant insect. C. ciliata could tolerate subzero temperatures by supercooling. Temperature around -8 degres C is a critical point for successful overwintering of C. ciliata adults, which can establish in the whole areas where Platanus trees are planted in China.

Purpose: The cancer stem cells play an important role in the invasion, metastasis and relapse of cancers as they are resistant to regular chemotherapy. In the present study, stealth liposomal daunorubicin plus tamoxifen was developed for eradicating breast cancer cells together with cancer stem cells., Methods: Inhibitory effects were performed on the bulk human breast cancer cells (MCF-7), the sorted MCF-7 cancer stem-like cells (side population, SP), and the sorted MCF-7 cancer cells (NSP), respectively. Antitumor activity and TUNEL analysis were evaluated on the MCF-7 xenografts in nude mice., Results: The encapsulation efficiencies of daunorubicin and tamoxifen were 95% and 90%, respectively. The mean particle size of the stealth liposomes was about 100 nm. Breast cancer stem cells were identified by the specific markers CD44+/CD24-, and isolated from bulk MCF-7 cells. When applying stealth liposomal daunorubicin plus tamoxifen, the inhibitory effects on both the breast cancer cells and the cancer stem cells were significantly increased in vitro, respectively. In the MCF-7 xenografts in mice, stealth liposomal daunorubicin plus tamoxifen showed the most favorable antitumor activity due to the passive targeting the tumor tissue and the synergistic effects in eliminating breast cancer cells and cancer stem cells., Conclusion: Stealth liposomal daunorubicin plus tamoxifen could have the potentials in eliminating both breast cancer cells and cancer stem cells.

With Cocos nucifera, Hyophorbe lagenicaulis, Washingtonia filifera, Roystonea regia and Areca catechu as test host plants, this paper studied the effects of their un-spread leaves on the development and fecundity of experimental population of Brontispa longissima. The results showed that the development duration of one generation B. longissima fed on different hosts varied significantly, with the longest (72.8 days) on W. filifera and the shortest (39.8 days) on H. lagenicaulis. The average pupa weight of B. longissima was bigger on H. lagenicaulis than on the other four host plants, and the female B. longissima had the highest fecundity (157.6 ova) on W. filifera while the lowest one (65.2 ova) on A. catechu. The longevity of B. longissima adults fed on H. lagenicaulis was 207.52 days, being significantly longer than that on the other host plants. The trend index of experimental population of B. longissima fed on the five host plants was 53.57, 54.98, 48.56, 20.46 and 11.54, respectively.