Need for dental care among medical staff working in the China Antarctic stations.

Even though China Antarctic medical care has made huge progress, dental care has always been a neglected area. Dental health is well-known to be closely related with life quality and work efficiency. Hence, knowing the dental care situation there and providing ways to improve are urgently needed. We choose doctors who worked in China Antarctic station as a window to see the whole picture by sending questionnaire. The results showed dental visits ranked second high, the ratio of doctors who got pre-departure dental knowledge education and screen is low. What is worse, none of them got any after-departure dental check. Their dental knowledge is not as good as we expect, and they were troubled by dental problems in Antarctic. Interestingly, most dental problems were treated by non-dentist with no essential equipment, but 2/3 of them were satisfied with the outcome. As for the dental-related diet and behaviour, snacks eating and alcohol drinking are the strongest predictors of dental pain and gum problem. Those findings are crucial to Antarctic dental care and research.

Effects of donor fibroblast cell type and transferred cloned embryo number on the efficiency of pig cloning.

Currently, cloning efficiency in pigs is very low. Donor cell type and number of cloned embryos transferred to an individual surrogate are two major factors that affect the successful rate of somatic cell nuclear transfer (SCNT) in pigs. This study aimed to compare the influence of different donor fibroblast cell types and different transferred embryo numbers on recipients' pregnancy rate and delivery rate, the average number of total clones born, clones born alive and clones born healthy per litter, and the birth rate of healthy clones (=total number of healthy cloned piglets born /total number of transferred cloned embryos). Three types of donor fibroblasts were tested in large-scale production of cloned pigs, including fetal fibroblasts (FFBs) from four genetically similar Western swine breeds of Pietrain (P), Duroc (D), Landrace (L), and Yorkshire (Y), which are referred to as P,D,LY-FFBs, adult fibroblasts (AFBs) from the same four breeds, which are designated P,D,L,Y-AFBs, and AFBs from a Chinese pig breed of Laiwu (LW), which is referred to as LW-AFBs. Within each donor fibroblast cell type group, five transferred cloned embryo number groups were tested. In each embryo number group, 150-199, 200-249, 250-299, 300-349, or 350-450 cloned embryos were transferred to each individual recipient sow. For the entire experiment, 92,005 cloned embryos were generated from nearly 115,000 matured oocytes and transferred to 328 recipients; in total, 488 cloned piglets were produced. The results showed that the mean clones born healthy per litter resulted from transfer of embryos cloned from LW-AFBs (2.53 ± 0.34) was similar with that associated with P,D,L,Y-FFBs (2.72 ± 0.29), but was significantly higher than that resulted from P,D,L,Y-AFBs (1.47 ± 0.18). Use of LW-AFBs as donor cells for SCNT resulted in a significantly higher pregnancy rate (72.00% vs. 59.30% and 48.11%) and delivery rate (60.00% vs. 45.93% and 35.85%) for cloned embryo recipients, and a significantly higher birth rate of healthy clones (0.5009% vs. 0.3362% and 0.2433%) than that resulting from P,D,L,Y-AFBs and P,D,L,Y-FFBs. This suggests that using LW-AFBs as donor cells results in a higher cloning efficiency in pigs, compared with the other two donor fibroblast cell types. The birth rate of healthy clones was significantly improved when the number of transferred cloned embryos was increased from 150-199 to 200-450 per recipient. However, increase of the number of transferred embryos from 200-249 to 250-450 per surrogate did not change the birth rate of healthy clones. This suggests that transfer of excessive (250-450) cloned embryos to an individual surrogate is not necessary for increasing the cloning efficiency in pigs, and the relatively optimal number of reconstructed embryos transferred to individual recipient is 200-249. Furthermore, our results indicated that the numbers of total born clones, clones born alive, and clones born healthy per litter have a significantly high positive correlation with each other. The present study provides useful information for improving SCNT efficiency in pigs.

The mode of yearly biological cycle of malignant growth of hepatocellular carcinoma on computed tomography.

OBJECTIVE: To detect the mode of yearly biological cycle of malignant biological behavior of hepatocellular carcinoma (HCC). METHODS: Twenty-one kinds of CT signs reflecting various degrees of malignant biological behavior were determined. A total of 360 patients were collected by random sampling of 30 patients each month. CT signs of each patient were fitted in corresponding group of yearly cyclic data respectively by cosine curves and analysed in terms of sequence characteristics (cosinor). RESULTS: With a 95% confidence, 10 CT signs showed biological rhythm (P<0.05). The acrophase of CT features for highly-invasive growth concentrated between -60 degree and -120 degree from March to April. For low-invasive growth, however, the CT features were relatively low and concentrated between -180 degrees and -270 degrees from July to September. No acrophase was shown between -120 degrees and -180 degrees from May to June, and between -270 degrees and -330 degrees from October to November. CONCLUSION: Between CT signs of the highly-invasive and those of low-invasive growth of HCC, a sequential difference in biological cycles can be observed.

[Comparison of the yearly cycle cosine curve imitative parameters of the clinical features of liver cancer at different longitude and latitude].

OBJECTIVE: To explore whether there exists coincidence of the most appearing time of clinical features of liver cancer at different longitude and latitude, according to the law of field equation and the theory of warpage of space time by Einstein. METHODS: Three regions with different longitude and latitude were selected randomly and sampled. There were 36 items altogether, including 12 clinical items, which were used to imitate the yearly cycle cosine curve. The acorphases and the ratioes of amplitudes and means were compared to justifying whether they were in the same range. RESULTS: All the acorphases of 36 items appeared between -90.1degrees to -207.5 degrees (from april to july), existing in one third of the same range, in which 13 items occurred rhythmly (P<0.05). The image acorphases of liver cancer at the early and middle stage and gamma-glutamyl transpeptidase acorphase appeared between -98.5 degrees to -148.2 degrees (from april to may), in which 5 items occurred rhythmly (P<0.05). CONCLUSION: It is the same mode of the yearly biologcal cycle for liver cancer malignant growth within the most appearing time (from april to july). It will increase the detecting rate of liver cancer at the early and middle stage during this time (especially from april to may).