[Effect of diets with different fat levels on the body size and development of Lucilia sericata].

OBJECTIVE: To observe the effect of diets with different fat levels on the body size and development of Lucilia sericata. METHODS: Under the constant temperature of 28 degrees C, the larvae were reared on the diets containing 0% (G0), 10% (G1), 30% (G3), 50% (G5) and 80% (G8) fat tissues (fat/muscle ratio), respectively. Length and weight of larvae and pupae were measured at 12 h interval since 16 h after eclosion. Length of inter-medial cross vein (m-m) of adult left wing was measured. 10 samples were collected in each group. The developmental duration time, mortality and sex ratios of adults were recorded. RESULTS: The mean maximal larval length [(13.3 +/- 1.2), (12.0 +/- 1.1), (10.2 +/- 0.9) and (8.8 +/- 0.8) mm, respectively] and mean maximal larval weight [(72.8 +/- 6.1), (62.2 +/- 5.7), (47.2 +/- 4.3), and (34.9 +/- 5.7) mg] in G1, G3, G5 and G8 groups were significantly less than that of the G0 group [(14.8 +/- 1.3) mm and (80.4 +/- 8.1) mg](P < 0.01). The body size of pupae and adults was also significantly less than that of G0 group (P < 0.01). The total duration time of G5 and G8 groups [(293.3 +/- 22.2) and (285.2 +/- 24.6) h] were significantly shorter than that of G0 group [(312.8 +/- 20.1)h] (P < 0.01). The mortality of larvae [(32.6 +/- 5.6)% and (44.3 +/- 7.7)%] and pupae [(28.6 +/- 5.5)% and (43.5 +/- 6.2)%] of G5 and G8 group were also significantly higher than that of G0 group [(5.7 +/- 3.3)% and (4.5 +/- 1.9)%] (P < 0.01). There was no significant difference in sex ratio among the 5 groups (P > 0.05). CONCLUSION: The body size of larvae, pupae and adults of Lucilia sericata is smaller, the development time is shorter and mortality is higher when the food substrate contains more fat tissues.

[Effect of feeding on different tissues on larva development of Lucilia sericata].

OBJECTIVE: To observe the effect of feeding on different pig tissues on the development of Lucilia sericata larvae. METHODS: Under a constant temperature of 25 degrees C, about 200 larvae each were reared on four different substrates, i.e. pig's brain, liver, muscle and a mixture of minced pork muscle and fat (6:4). Length and weight of larvae and pupae were measured at 12 h interval 16 h after eclosion. The time of development, mortality, sex ratio of adults were recorded. RESULTS: Compared to the other groups, the larvae of liver and mixture groups grew slower, time of reaching maximum length and weight was delayed for 12-24 h. The duration of larva development of liver group [(284.0 +/- 12.6) h] was longer than that of brain group [(257.0 +/- 11.9) h], muscle group [(258.0 +/- 10.2) h] and mixture group [(260.0 +/- 9.8) h] (P < 0.05). The mean maximum larva length and weight in mixture group [(11.85 +/- 0.36) mm, (40.4 +/- 0.2) mg] and liver group [(12.01 +/- 0.43) mm, (42.8 +/- 0.4) mg] was statistically less than that of brain group and muscle group (P < 0.05). The pupal length and weight in mixture group [(7.81 +/- 0.60) mm, (38.4 +/- 2.4) mg] was less than that of other three groups (P < 0.05). The larval and pupal mortality of mixture group [(9.8 +/- 2.4)% and (10.3 +/- 1.8)%] was statistically higher than that of other three groups (P < 0.05). There was no significant difference in the sex ratio among the four groups (P > 0.05). CONCLUSION: The development duration of the larvae fed on liver tissue is longer than other groups, and the larvae body length and weight of liver group are less than other groups. The body length and weight of larvae and pupae fed on mixture diet are less than other groups with higher mortality.

[Effect of feeding on different tissues on larva development of Chrysomya megacephala (Diptera: Calliphoridae)].

OBJECTIVE: To observe the effect of feeding on different pig tissues on the development of Chrysomya megacephala larvae. METHODS: About 200 larvae each were reared on four different substrates, i.e. pig's brain, liver, muscle and a mixture of minced pork muscle and fat (7 : 3) at a constant temperature of 25 degrees C. Length and weight of larvae and pupae were measured at 12 h interval 16 h after eclosion. 10 larvae or pupae were collected each time. The time of development, mortality, and sex ratio of adults were recorded. RESULTS: Three replicated experiments showed that the larvae fed on liver grew slowly, time of reaching maximum length and weight was delayed for about 24-36 h, and the duration of larva development was longer than that of other groups (P<0.01). The mean maximal larval length in mixture group [(14.89 +/- 0.39) mm] was statistically shorter than that of brain group, muscle group and liver group, [(17.81 +/- 0.54), (16.94 +/- 0.43) and (17.14 +/- 0.27) mm, respectively] (P<0.01). The mean maximal larval weight in liver group [(73.5 +/- 6.8) mg] and mixture group [(63.0 +/- 5.4) mg] was statistically lighter than brain group [(91.2 +/- 7.5) mg] and muscle group [(86.3 +/- 7.3) mg] (P<0.01). The pupal length in mixture group was statistically shorter than that of other 3 groups (P<0.01). The pupal weight of mixture group and liver group was statistically lighter than that of brain group and muscle group (P<0.01). The larval and pupal mortality of mixture group [(9.8 +/- 3.1)% and (8.9 +/- 3.1)%] was statistically higher than that of brain group [(5.5 +/- 3.1)% and (4.6 +/- 1.5)%], muscle group [(4.7 +/- 2.2)% and (3.8 +/- 2.0)%] and liver group [(5.4 +/- 2.3)% and (4.8 +/- 1.7)%] (P<0.01). There was no significant difference in the sex ratio among the four groups (P>0.05). CONCLUSION: The development duration of the larvae fed on liver is longer than other groups. The body length and weight of larvae and pupae fed on mixture diet are less than other groups with higher mortality.

Plant developmental stage drives the differentiation in ecological role of the maize microbiome.

BACKGROUND: Plants live with diverse microbial communities which profoundly affect multiple facets of host performance, but if and how host development impacts the assembly, functions and microbial interactions of crop microbiomes are poorly understood. Here we examined both bacterial and fungal communities across soils, epiphytic and endophytic niches of leaf and root, and plastic leaf of fake plant (representing environment-originating microbes) at three developmental stages of maize at two contrasting sites, and further explored the potential function of phylloplane microbiomes based on metagenomics. RESULTS: Our results suggested that plant developmental stage had a much stronger influence on the microbial diversity, composition and interkingdom networks in plant compartments than in soils, with the strongest effect in the phylloplane. Phylloplane microbiomes were co-shaped by both plant growth and seasonal environmental factors, with the air (represented by fake plants) as its important source. Further, we found that bacterial communities in plant compartments were more strongly driven by deterministic processes at the early stage but a similar pattern was for fungal communities at the late stage. Moreover, bacterial taxa played a more important role in microbial interkingdom network and crop yield prediction at the early stage, while fungal taxa did so at the late stage. Metagenomic analyses further indicated that phylloplane microbiomes possessed higher functional diversity at the early stage than the late stage, with functional genes related to nutrient provision enriched at the early stage and N assimilation and C degradation enriched at the late stage. Coincidently, more abundant beneficial bacterial taxa like Actinobacteria, Burkholderiaceae and Rhizobiaceae in plant microbiomes were observed at the early stage, but more saprophytic fungi at the late stage. CONCLUSIONS: Our results suggest that host developmental stage profoundly influences plant microbiome assembly and functions, and the bacterial and fungal microbiomes take a differentiated ecological role at different stages of plant development. This study provides empirical evidence for host exerting strong effect on plant microbiomes by deterministic selection during plant growth and development. These findings have implications for the development of future tools to manipulate microbiome for sustainable increase in primary productivity. Video Abstract.

[Polymorphisms of 11 Y-chromosomal short tandem repeat loci in Chongqing Tujia ethnic group and genetic relationships with 16 populations].

OBJECTIVE: To investigate the genetic polymorphisms of 11 Y-chromosomal short tandem repeats (STR) loci in Chongqing Tujia population, and to evaluate their forensic application values and genetic relationships with the other 16 populations of China. METHODS: Eleven Y-STR loci in 215 unrelated Tujia individuals from Chongqing were amplified with PowerPlex Y System, and the PCR products were analyzed by 310 Genetic Analyzer. Cluster analysis and phylogenic trees were applied to show the genetic distance among the populations. RESULTS: A total of 195 haplotypes were identified and the overall haplotypes diversity for the 11 Y-STR loci was 0.9942. The gene diversity values (GD) for each locus ranged from 0.3757 (DYS391) to 0.9170 (DYS385a/b). Comparing with other 16 populations, the genetic distance between Tujia and Tibetan was the nearest (0.02467), that between the Tujia and Korean ethnic groups was the farthest (0.25350). CONCLUSION: The genetic distribution of the 11 Y-STR loci in Chongqing Tujia population showed favorable polymorphisms. They are suitable for forensic identification and paternity testing in the local area. The study of genetic diversity among different populations is useful in understanding their origins, migrations and their relationships.

[Heteroplasmy in human mtDNA control region].

OBJECTIVE: To observe the length heteroplasmy and point heteroplasmy in human mtDNA control region. METHODS: The peripheral blood, buccal cell, and single hair shaft from 50 individuals and 16 family members, related in their maternallineage were analyzed by direct sequencing, and clones from 20 individuals whose mtDNA sequences have a T-C transition at 16189 nt were sequenced. RESULTS: No point heteroplasmy were observed in peripheral blood, buccal cell, single hair shaft from the same individual, neither in maternally related individuals. Length heteroplasmy was observed in those individuals with a homopolymeric tract and the different clones from the same individual has different proportions of length variants, but the hair shafts from the same individual were very similar to the measurements made from blood DNA. No length heteroplasmy was observed between different tissues from the same individual. CONCLUSION: mtDNA sequences have a characteristic of high consistency and genetic stability, mtDNA sequencing is a suitable tool for forensic applications such as individual identification.

A checklist of beetles (Insecta, Coleoptera) on pig carcasses in the suburban area of southwestern China: A preliminary study and its forensic relevance.

Examining the succession pattern of carrion insects on vertebrate carcasses is widely accepted as an effective method to estimate the postmortem interval (PMI) of decayed bodies. Investigation of the community of sarcosaprophagous insects, especially flies and beetles, is the foundation of the succession pattern study. This study aimed to investigate the sarcosaprophagous beetles succession on animal carcasses in the suburban area of southwestern China and to establish a basic catalog for forensic application. The present study was conducted in 2013 in a mountain in Chongqing municipality with modified Schoenly traps. Carcasses of miniature pig were used to simulate human bodies. For most carcasses, five decomposition stages were observed. A total of 2108 adult coleopterans belonging to at least 61 species and 18 families were collected in the study, and most of the specimens occurred at the advanced decay stage. Omosita colon (Linnaeus, 1758), Necrodes nigricornis (Harold, 1875), Necrobia ruficollis (Fabricius, 1775) and Neosilusa ceylonica (Kraatz, 1857) were the dominant species.

Developmental Times of Chrysomya megacephala (Fabricius) (Diptera: Calliphoridae) at Constant Temperatures and Applications in Forensic Entomology.

The characteristic life stages of infesting blowflies (Calliphoridae) such as Chrysomya megacephala (Fabricius) are powerful evidence for estimating the death time of a corpse, but an established reference of developmental times for local blowfly species is required. We determined the developmental rates of C. megacephala from southwest China at seven constant temperatures (16-34°C). Isomegalen and isomorphen diagrams were constructed based on the larval length and time for each developmental event (first ecdysis, second ecdysis, wandering, pupariation, and eclosion), at each temperature. A thermal summation model was constructed by estimating the developmental threshold temperature D0 and the thermal summation constant K. The thermal summation model indicated that, for complete development from egg hatching to eclosion, D0 = 9.07 ± 0.54°C and K = 3991.07 ± 187.26 h °C. This reference can increase the accuracy of estimations of postmortem intervals in China by predicting the growth of C. megacephala.

Technical note: Development of Hemipyrellia ligurriens (Wiedemann) (Diptera: Calliphoridae) at constant temperatures: Applications in estimating postmortem interval.

Blowflies (Calliphoridae) are recognized as a powerful tool for estimating the minimum postmortem interval (PMImin). The times for blowflies to develop from oviposition to eclosion is mainly controlled by temperature, which can differ between even closely related species. Hemipyrellia ligurriens (Wiedemann) (Diptera: Calliphoridae) is a blowfly distributed throughout Asia and Australia. However, a systematic determination of the developmental times of H. ligurriens under constant temperature, necessary for estimating the PMImin, is lacking. Such an examination would broaden the forensic importance of the species. Thus, this study explored the growth curves of larval H. ligurriens at 7 constant temperatures (16, 19, 22, 25, 28, 31, and 34°C). Isomegalen and isomorphen diagrams were successfully constructed, depicting the time of larval length or developmental event, respectively, at different temperatures. A thermal summation model was also constructed via regression analysis, by estimating the developmental threshold temperature t and thermal summation constant K. The thermal summation model indicated that t at 8.3°C and K at 5747.5 degree-hours (°Ch) are required for complete development from oviposition to eclosion, and suggested an optimum temperature range of 16-28°C for the development of H. ligurriens. These data establish for the first time the temperature-dependent developmental time of H. ligurriens for forensic entomology application. The 3 developmental models are provided.

[Rapid Start-up of Simultaneous Nitrification and Denitrification Coupled Phosphorus Removal Process and Its Performing Characteristics].

In this study, simultaneous nitrification and denitrification (SND) coupled Phosphorus removal process through gradually decreasing DO concentration was investigated by treating wastewater with a low COD/TN ratio (C/N = 3 : 1-4: 1) in a sequencing batch reactor (SBR) inoculated with aerobic granular sludge (AGS). Successful SND coupled Phosphorus phenomenon occurred after 20d at the DO concentration of 0.50-1.0 mg x L(-1). In the following 40 days, the average removal rates of COD, NH4(+) -N, TN and TP were 84.84% , 93.51%, 77.06% and 85.69%, and the NO3(-) -N and NO2(-) -N average accumulations in the effluent were only 4.01 mg x L(-1) and 3.17 mg x L(-1), respectively. The AGS had complete forms and good settling performances, and the sludge volume index (SVI) was about 55.22 mL x g(-1) at the end of starting-up stage. The results of different nitrogen sources showed that the removal rate of TN was in the order of NH4(+) -N > NO2(-) -N > NO3(-) -N, and the removal rate of TP was in the order of NO3(-) -N > NO2(-) -N > NH4(+) -N. The nitrogen and phosphorus removal of wastewater were mainly realized by simultaneous nitrification and denitrification and denitrifying phosphorus removal, respectively.

Survivin gene functions and relationships between expression and prognosis in patients with nasopharyngeal carcinoma.

This study aimed to investigate the relationship between prognosis and protein and mRNA expression of an apoptotic inhibitor gene, survivin, in patients with nasopharyngeal carcinoma. Furthermore, functions of the survivin gene in the CNE2 nasopharyngeal carcinoma cell line were assessed. Immunohistochemistry and in situ hybridization were used in detecting the survivin protein and mRNA in 44 nasopharyngeal carcinoma specimens, and 30 chronic nasopharyngitis samples as controls. Survivin gene expression in CNE2 cell line was suppressed with an shRNA (short hairpin RNA). The positive ratios of expression for survivin protein and mRNA in nasopharyngeal carcinoma were 79.5% and 75.0% respectively, obviously higher than in the control group (p<0.01), and there is very good consistency between the two methods. The mean survival time of patients with higher survivin protein or mRNA expression was shorter than in patients with lower levelsv(p<0.01). Proliferation of the CNE2 cell line was distinctly inhibited by the shRNA . The results indicate that overexpression of the survivin gene plays an important role in onset and development of nasopharyngeal carcinoma, and it may be helpful for prognostic appraisal.

The role of IGFBP-5 in mediating the anti-proliferation effect of tetrandrine in human colon cancer cells.

Colon cancer is one of the most common malignancies, causes considerable morbidity and mortality. The current treatment for colon cancer is more modest than had been hoped. There is an urgent clinical need to explore new agents or adjuvants for colon cancer treatment. Natural products and their derivates act as one of the major source for anticancer agent. In the present study, we investigated the anti-proliferation and chemoprevention effects of tetrandrine (Tet) on colon cancer cells to uncover the possible molecular basis of this effect. We found that Tet can inhibit proliferation and induce apoptosis in LoVo cells. With dimethylhydrazine (DMH) and dextran sodium sulfate (DSS) induced colon cancer model, we found that Tet can prevent or inhibit DMH plus DSS induced aberrant crypt foci (ACF) and colon cancer formation, as well as suppress tumor growth in the xenograft colon cancer model. Tet can downregulate the expression of IGFBP-5 in LoVo cells. Exogenous expression of IGFBP-5 can attenuate the anti-cancer activity of Tet, while IGFBP-5 knockdown potentiates this effect of Tet on LoVo cells. Tet can inhibit Wnt/ß-catenin signaling transduction, which can be partly reversed by exogenous expression of IGFBP-5, but is enhanced by IGFBP-5 knockdown. Our results demonstrated that the anticancer activity of Tet in colon cancer cells may be mediated partly by downregulating the expression of IGFBP-5, thus inactivating Wnt/ß-catenin signaling transduction.

Developing a novel panel of genome-wide ancestry informative markers for bio-geographical ancestry estimates.

Inferring the ancestral origin of DNA samples can be helpful in correcting population stratification in disease association studies or guiding crime investigations. Populations throughout the world vary in appearance features and biological characteristics. Based on this idea, we performed a genome-wide scan for SNPs within genes that are related to physical and biological traits. Using the HapMap database, we screened 52 genes and their flanking regions. Thirty-five SNPs that displayed highly contrasting allele frequencies (F(st)>0.3, linkage disequilibrium r(2)<0.2, and Hardy-Weinberg equilibrium P>0.001) among Africans, Europeans, and East Asians were selected and validated. A multiplexed assay was developed to genotype these 35 SNPs in 357 individuals from 10 populations worldwide. This panel provided accurate estimates of individual ancestry proportions with balanced discriminatory power among the three continental ancestries: Africans, Europeans, and East Asians. It also proved very effective in evaluating admixed populations living in joint regions of continents (e.g., Uyghurs and Indians) and discriminating some subpopulations within each of the three continents. Structure analysis was performed to establish and evaluate the panel of ancestry-informative markers, and the components of each population were also described to indicate the structural composition. The 21 population structures in our study are consistent with geographic patterns, and individuals were properly assigned to their original ancestral populations with proportion analyses and random match probability calculations. Thus, the panel and its population information will be useful resources to minimize the effects of population stratification in association analyses and to assign the most likely origin of an unknown DNA contributor in forensic investigations.