Hidden diversity and potential ecological function of phosphorus acquisition genes in widespread terrestrial bacteriophages.

Phosphorus (P) limitation of ecosystem processes is widespread in terrestrial habitats. While a few auxiliary metabolic genes (AMGs) in bacteriophages from aquatic habitats are reported to have the potential to enhance P-acquisition ability of their hosts, little is known about the diversity and potential ecological function of P-acquisition genes encoded by terrestrial bacteriophages. Here, we analyze 333 soil metagenomes from five terrestrial habitat types across China and identify 75 viral operational taxonomic units (vOTUs) that encode 105 P-acquisition AMGs. These AMGs span 17 distinct functional genes involved in four primary processes of microbial P-acquisition. Among them, over 60% (11/17) have not been reported previously. We experimentally verify in-vitro enzymatic activities of two pyrophosphatases and one alkaline phosphatase encoded by P-acquisition vOTUs. Thirty-six percent of the 75 P-acquisition vOTUs are detectable in a published global topsoil metagenome dataset. Further analyses reveal that, under certain circumstances, the identified P-acquisition AMGs have a greater influence on soil P availability and are more dominant in soil metatranscriptomes than their corresponding bacterial genes. Overall, our results reinforce the necessity of incorporating viral contributions into biogeochemical P cycling.

Functional Guilds, Community Assembly, and Co-occurrence Patterns of Fungi in Metalliferous Mine Tailings Ponds in Mainland China.

Metalliferous mine tailings ponds are generally characterized by low levels of nutrient elements, sustained acidic conditions, and high contents of toxic metals. They represent one kind of extreme environments that are believed to resemble the Earth's early environmental conditions. There is increasing evidence that the diversity of fungi inhabiting mine tailings ponds is much higher than previously thought. However, little is known about functional guilds, community assembly, and co-occurrence patterns of fungi in such habitats. As a first attempt to address this critical knowledge gap, we employed high-throughput sequencing to characterize fungal communities in 33 mine tailings ponds distributed across 18 provinces of mainland China. A total of 5842 fungal phylotypes were identified, with saprotrophic fungi being the major functional guild. The predictors of fungal diversity in whole community and sub-communities differed considerably. Community assembly of the whole fungal community and individual functional guilds were primarily governed by stochastic processes. Total soil nitrogen and total phosphorus mediated the balance between stochastic and deterministic processes of the fungal community assembly. Co-occurrence network analysis uncovered a high modularity of the whole fungal community. The observed main modules largely consisted of saprotrophic fungi as well as various phylotypes that could not be assigned to known functional guilds. The richness of core fungal phylotypes, occupying vital positions in co-occurrence network, was positively correlated with edaphic properties such as soil enzyme activity. This indicates the important roles of core fungal phylotypes in soil organic matter decomposition and nutrient cycling. These findings improve our understanding of fungal ecology of extreme environments.

Sporoderm-broken spore powder of Ganoderma lucidum ameliorate obesity and inflammation process in high-fat diet-induced obese mice.

Objective: This study examined the anti-obesity and anti-inflammatory effects of sporoderm-broken spore powder of Ganoderma lucidum (SSPL) against obese mice fed with a high-fat diet. Methods: Four groups of C57BL/6J mice were randomly assigned to the following diets: control diet (CD); high-fat diet (HD); high-fat diet plus l-carnitine (HDL); and high-fat diet with sporoderm-broken spore powder of Ganoderma lucidum (HDG). They were subjected to 12 weeks of testing. Results: Supplementation with SSPL lowered weight gain caused by a high-fat diet and improved serum and liver lipid levels, and histological investigation indicated that the HDG group had a significant reduction in liver lipid deposits and adipocyte size in epididymal fat. SSPL administration decreased the expression of genes associated with inflammation and fat anabolism, including tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), interleukin-1ß (IL-1ß), peroxisome proliferator-activated receptorγ (PPARγ), sterol regulatory element-binding protein 1c (SREBP-1c), fatty acid synthase (FAS), acetyl-coenzyme A (CoA) carboxylase (ACC), and leptin. SSPL therapy raised the levels of PPARα, carnitine palmitoyl-transferase 1 (CPT-1), acyl-CoA oxidase1 (ACOX1), and adiponectin. Conclusion: In summary, SSPL protected mice against developing obesity caused by increased fat intake by regulating inflammatory factors and lipid metabolism. Our findings indicate that SSPL is a potentially beneficial healthy meal for treating obesity.

Course of disease and related epidemiological parameters of COVID-19: a prospective study based on contact tracing cohort / 中华预防医学杂志

Objective: To analyze the course of disease and epidemiological parameters of COVID-19 and provide evidence for making prevention and control strategies. Methods: To display the distribution of course of disease of the infectors who had close contacts with COVID-19 cases from January 1 to March 15, 2020 in Guangdong Provincial, the models of Lognormal, Weibull and gamma distribution were applied. A descriptive analysis was conducted on the basic characteristics and epidemiological parameters of course of disease. Results: In total, 515 of 11 580 close contacts were infected, with an attack rate about 4.4%, including 449 confirmed cases and 66 asymptomatic cases. Lognormal distribution was fitting best for latent period, incubation period, pre-symptomatic infection period of confirmed cases and infection period of asymptomatic cases; Gamma distribution was fitting best for infectious period and clinical symptom period of confirmed cases; Weibull distribution was fitting best for latent period of asymptomatic cases. The latent period, incubation period, pre-symptomatic infection period, infectious period and clinical symptoms period of confirmed cases were 4.50 (95%CI:3.86-5.13) days, 5.12 (95%CI:4.63-5.62) days, 0.87 (95%CI:0.67-1.07) days, 11.89 (95%CI:9.81-13.98) days and 22.00 (95%CI:21.24-22.77) days, respectively. The latent period and infectious period of asymptomatic cases were 8.88 (95%CI:6.89-10.86) days and 6.18 (95%CI:1.89-10.47) days, respectively. Conclusion: The estimated course of COVID-19 and related epidemiological parameters are similar to the existing data.

Data analysis of surveillance results of iodine deficiency disorders in Guangdong Province in 2011 / 中国地方病学杂志

Objective To assess the effectiveness of prevention program on iodine deficiency disorders and iodine nutritional status of residents in Guangdong Province.Methods Probability proportionate to size sampling(PPS) was employed in surveillance of iodine deficiency disorders.Thirty counties(cities,districts) were selected in Guangdong Province.In each county(city,district) one township(street) was selected; in each township (street) one primary school was selected and in each primary school 40 children aged 8-10 were chosen to examine their thyroid and to collect salt samples at their home for determination of salt iodine.Out of the 40 children,12 children were chosen to collect urine samples for determination of urinary iodine.From the primary schools chosen,40 grade 5 students were selected for intelligence quotient(IQ) test.In the nearby of the primary schools,3 townships(towns,street) were selected and in each township(town,street) 5 pregnant and 5 lactating women were selected to collect their urine samples for determination of urinary iodine.Type-B ultrasonic was used in measuring the thyroid volume.The iodine content of urine samples was measured by the method of arsenic and cerium catalysis spectrophotometry.The iodine content of salt was determined quantitatively with the titration method.IQ was tested by Chinese combined Raven's test.According to geographical location and the implementation of iodized salt,the effects of iodized salt on iodine deficiency disorders were analyzed in the plains and the Pearl River Delta Coastal region with mild iodine deficiency(iodized salt implementation region,referred to as the plains and the PRD),historical iodine deficiency areas (iodized implementation region) and the eastern and the western coastal areas of Guangdong(areas with non-iodized salt problem,referred to as the eastern and the western Guangdong).Results A total of 1200 children aged 8 to 10 were examined by type-B ultrasonic test,and goiter rate was 3.5％ (42/1200).The differences of goiter rate between the plains and the PRD,the historical iodine deficiency areas and the eastern and the western Guangdong were statistically significant (x2 =6.6,P ＜ 0.05).The goiter rate (6.1％) in the eastern and the western Guangdong was significantly higher than that of the plains and the PRD and the historical iodine deficiency areas (3.3％,2.0％,x2 =5.6,7.1,all P ＜ 0.05).A total of 1200 salt samples were examined.The median and coefficient of variation of iodine in the salt were 31.0 mg/kg and 23.2％,respectively.Coverage of iodized salt was 97.5％(1170/1200) while 96.1％(1153/1200) of consumed iodized salt was qualified.The median urinary iodine of 1200 children aged 8-10 was 186.5 μg/L,and the differences of median urinary iodine between the plains and the PRD,the historical iodine deficiency areas and the eastern and the western Guangdong were statistically significant(x2 =5.9,P ＜ 0.05).The median urinary iodine of the eastern and the western Guangdong(162.4 μg/L) was significantly lower than that of the plains and the PRD(207.5 μg/L,x2 =8.7,P ＜ 0.01).The difference of median urinary iodine between the plains and the PRD,the historical iodine deficiency areas and the eastern and the western Guangdong was statistically significant(x2 =58.9,P＜ 0.01).The median urinary iodine of the eastern and the western Guangdong(109.6 μg/L) was significantly lower than that of the historical iodine deficiency areas and the plains and the PRD(152.9,155.2 μg/L,x2 =18.3,20.6,all P ＜ 0.05).The mean IQ of the 1208 grade 5 students was 102.8 ± 14.3.The IQ of the plains and the PRD(104.3 ± 13.9) and the historical iodine deficiency areas(102.7 ± 14.3) was significantly higher than that of the eastern and the western Guangdong(100.3 ± 14.7,t =3.8,2.1,P＜ 0.01 orP＜ 0.05).Conclusions The goal of iodine deficiency disorders elimination is achieved as scheduled in Guangdong Province.The health level of general population has been improved significantly.Iodine nutrition is in the appropriate range (100-199 μg/L) in general population but low in pregnant women.The selling of non-iodized salt in the eastern and the western Guangdong Province should be followed closely.

Establishment of an artificial neural network model for analysis of the influence of climate factors on the density of Aedes albopictus / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish a model for predicting the density of Aedes albopictus based on the climate factors.</p><p><b>METHODS</b>The data of Aedes albopictus density and climate changes from 1995 to 2001 in Guangzhou were collected and analyzed. The predicting model for Aedes albopictus density was established using the Artificial Neural Network Toolbox of Matlab 7.0 software package. The climate factors used to establish the model included the average monthly pressure, evaporation capacity, relative humidity, sunshine hour, temperature, wind speed, and precipitation, and the established model was tested and verified.</p><p><b>RESULTS</b>The BP network model was established according to data of mosquito density and climate factors. After training the neural network for 25 times, the error of performance decreased from 0.305 539 to 2.937 51x10(-14). Verification of the model with the data of mosquito density showed a concordance rate of prediction of 80%.</p><p><b>CONCLUSION</b>The neural network model based on the climate factors is effective for predicting Aedes albopictus density.</p>

[Expression and clinical significance of COX-2, p-Stat3, and p-Stat5 in esophageal carcinoma].

BACKGROUND & OBJECTIVE: Cyclooxygenase-2 (COX-2) and signal transducers and activators of transcription (STAT) are closely correlated to the genesis of tumors. This study was to investigate the expression and clinical significance of COX-2, p-Stat3 and p-Stat5 (the activated forms of Stat3 and Stat5) in various lesions of esophageal tissues, and to analyze their correlations to clinicopathologic features of esophageal squamous cell carcinoma (ESCC). METHODS: The expression of COX-2, p-Stat3, and p-Stat5 in 59 specimens of ESCC, 24 specimens of squamous dysplasia, and 18 specimens of normal squamous epithelium was examined by SP immunohistochemistry. Their correlations to clinicopathologic features of ESCC were analyzed. RESULTS: The protein level of COX-2 was significantly higher in ESCC and squamous dysplasia than in normal squamous epithelium (2.10+/-1.77 and 1.85+/-1.24 vs. 0.83+/-0.46, P<0.05). The protein level of p-Stat3 was 0 in normal squamous epithelium, 0.76+/-0.59 in squamous dysplasia, and 2.83+/-1.27 in ESCC. The protein level of p-Stat5 was 1.98+/-0.78 in normal squamous epithelium, 3.92+/-0.41 in squamous dysplasia, and 5.02+/-0.34 in ESCC. There were significant differences among the 3 groups (P<0.05). In ESCC, COX-2 expression was correlated to lymph node metastasis and differentiation (P<0.05); p-Stat3 expression was correlated to tumor invasion depth (P<0.05); but p-Stat5 expression had no correlation to clinicopathologic features. COX-2 expression was positively correlated to both p-Stat3 expression and p-Stat5 expression in ESCC. CONCLUSIONS: The up-regulation of COX-2, p-Stat3, and p-Stat5 may be correlated to the carcinogenesis of ESCC. The activation of Stat3 is correlated to the aggressive behavior of ESCC.