Exclusive microbially driven autotrophic iron-dependent denitrification in a reactor inoculated with activated sludge.

Autotrophic iron-dependent denitrification (AIDD) is arising as a promising process for nitrogen removal from wastewater with a low carbon to nitrogen ratio. However, there is still a debate about the existence of such a process in activated sludge systems. This work provides evidence and elucidated the feasibility of autotrophic Fe(II)-oxidizing nitrate-reducing culture for nitrogen removal by long-term reactor operation, batch experimental verification, unstructured kinetic modeling and microbial community analyses. A relatively stable nitrate removal rate was achieved coupled with the oxidation of ferrous ions in 3-month operation of reactor. The kinetic modeling suggests that the iron oxidation was a growth-associated process in AIDD. Utilization of extracellular polymeric substances (and/or soluble microbial products) as electron donor for denitrification by heterotrophic denitrifiers was not mainly responsible for nitrogen removal in the reactor. After long-term operation of the reactor with activated sludge as inoculum, the enrichment culture KS-like consortium, dominated by Fe(II) oxidizer, Gallionellaceae, was successfully acclimated for autotrophic Fe(II)-oxidizing nitrate reduction. This work extents our understanding about the existence of such an autotrophic Fe(II)-oxidizing nitrate-reducing culture in both natural and engineered systems, and opens a door for its potential application in wastewater treatment.

Synthesis and biological evaluation of arylpiperazine derivatives as potential anti-prostate cancer agents.

A novel scaffold of arylpiperazine derivatives was discovered as potent androgen receptor (AR) antagonist through rational drug designation based on our pre-work, leading to the discovery of a series of new antiproliferative compounds. Compounds 10, 16, 27, 29 and 31 exhibited relatively strong antagonistic potency against AR and exhibited potent AR binding affinities, while compounds 5, 6, 10, 14, 16, 19, 21, 27 and 31 exhibited strong cytotoxic activities against LNCaP cells (AR-rich) as well as also displayed the higher activities than finasteride toward PC-3 (AR-deficient) and DU145 (AR-deficient). Docking study suggested that the most potent antagonist 16 mainly bind to AR ligand binding pocket (LBP) site through hydrogen bonding interactions. The structure-activity relationship (SAR) of these designed arylpiperazine derivatives was rationally explored and discussed. These results indicated that the novel scaffold compounds demonstrated a step towards the development of novel and improved AR antagonists, and promising candidates for future development were identified.

Newly identified type II crustin (SpCrus2) in Scylla paramamosain contains a distinct cysteine distribution pattern exhibiting broad antimicrobial activity.

Type II crustins are the most abundant type of crustins in shrimps that exhibit remarkable sequence diversities and broad antibacterial activities. This study characterized a novel type II crustin, SpCrus2, in the mud crab Scylla paramamosain. The SpCrus2 cDNA sequence is 620-bp long with a 495-bp open reading frame encoding a 164-amino acid protein. In the deduced protein, a 17-amino acid signal peptide, a glycine-rich hydrophobic region (GRR), and a cysteine-rich region (CRR) containing a whey acidic protein domain were predicted. SpCrus2 shares high similarity with most type II crustins (types IIa and IIb crustins) in shrimps but has a novel distribution pattern of cysteine residues that is distinct from most crustins. SpCrus2 and PlCrus3 from Pacifastacus leniusculus share high similarity and the same distribution pattern of cysteine residues. Thus, we proposed them as type IIc crustins. SpCrus2 is mainly distributed in the gills and can be up-regulated through Vibrio parahemolyticus or Staphylococcus aureus challenge. To investigate the biological functions of SpCrus2 and the underlying mechanisms, SpCrus2, GRR, CRR, and the mutant of CRR (CRR-M, the cysteine distribution pattern is mutated into that in most conventional crustins) were all overexpressed and purified. SpCrus2 GRR itself, as a glycine-rich amphiphilic peptide, exhibited evident antibacterial ability against Gram-negative bacteria, whereas CRR possessed potent antibacterial activity against Gram-positive bacteria. Either GRR or CRR exhibited weaker antibacterial activity than the whole protein of SpCrus2, indicating that GRR and CRR synergized to exert their potential antibacterial functions. In addition, CRR exhibited slightly stronger antimicrobial activity than CRR-M, suggesting that SpCrus2 containing this novel cysteine distribution pattern may exhibit stronger antimicrobial activity than most type II crustins with the conventional distribution pattern of cysteine residues. The likely antimicrobial ability of SpCrus2 may result from its microbial polysaccharide-binding and agglutination activities. Overall, this study characterized the first type II crustin in crabs and provided new insights into understanding the sequence and functional diversity of crustins and their immune functions in crustaceans.

[An Epidemiological Survey on Echinococcosis in Yushu Prefecture of Qinghai Province].

Objective: To investigate the prevalence of echinococcosis in Yushu Prefecture of Qinghai Province in 2012. Methods: Two to three towns were selected in each of Chengduo, Nangqian, Qu malai, Yushu, Zaduo and Zhiduo Counties from June to August in 2012. Ultrasound examination was conducted for residents aged over 1 year, and ELISA was performed to detect serum antibody against Echinococcus. Visceral dissection was performed to detect hydatid infection in rodents and livestock. ELISA was used to detect Echinococcus antigen in collected dog feces. Results: A total of 7 025 residents received ultrasound examination, of whom 319 showed hydatid cysts with a morbidity rate of 4.54%. ELISA showed a serum antibody positive rate of 16.38% （457/2 790）. The mobidity of hydatid disease was highest in Chengduo County （7.41%, 181/2 444）, and the rate of serum antibody was highest in Yushu County （23.18%, 127/548）. The morbidity and serum antibody in males were 3.91% （118/3 018） and 13.93% （172/1 235） respectively, and those in females were 5.02% （201/4 007） and 18.33% （285/1 555）. In terms of age distribution, the morbidity was relatively higher in residents of 60- （8.39%, 38/453） and 40- years （6.61%, 67/1 014）; and the rate of serum antibody was highest in residents over 70 years （33.93%, 19/56）. In terms of occupation, the morbidity was relatively higher in herdsmen （5.28%, 252/4 777）, Herdsmen-peasants （6.52%, 24/368）, and religious workers（3.37%, 11/326）, while the rate of serum antibody was relatively higher in children（24%, 6/25）, religious workers （18.79%, 31/165） and herdsmen（18.34%, 328/1 788）. In terms of education level, the morbidity and the rate of serum antibody were both highest in the uneducated（5.04%, 41/4 779; 18.34%, 359/1 958, respectively）. In terms of residential pattern, the morbidity and the rate of serum antibody were both highest in those who were settled in winter and nomadic in summer （8.25%, 227/2 753; 19.48%, 158/811, respectively）. There were significant differences in the morbidity and the rate of serum antibody in aspects of residential region, sex, age, occupation, education level and residential pattern (P<0.05 or P<0.01). In 872 rodents detected, the Echinococcus hydatid rate was 0.46% （4/872）, while in 809 cattle and sheep detected, the Echinococcus hydatid rate was 10.14% （82/809）. The fecal antigen positive rate in 838 samples of dog feces was 10.74%（90/838）. Conclusion: It shows a high morbidity of hydatid diesease and serum antibody positive rate in residents, a high Echinococcus hydatid rate in cattle and sheep, and a high fecal antigen positive rate in dogs in Yushu Prefecture.

[Survey on Echinococcosis in Maqing County of Qinghai Province].

OBJECTIVE: To understand the status of echinococcosis in Maqing County of Qinghai Province in order to facilitate echinococcosis control in this region. METHODS: Ultrasonic scanning and indirect hemagglutination assay were used to detect echinococcosis infection in residents >1 year old, according to the People's Republic of China Health Industry Standard--Diagnostic Criteria for Hydatid Disease (WS257-2006). Meanwhile, ELISA was used o detect the Echinococcus antigen in dog's feces collected in Youyun, Dangluo and Xiadawu townships. RESULTS: Ultrasonic scanning showed that the prevalence of hydatid disease in the residents was 7.4% (116/1 561), cystic hydatid disease 5.3% (82/1 561), alveolar hydatid disease 2.2% (34/1 561). The serum positive rate in human population was 23.8%(307/1 288). Of the 82 cases of cystic hydatid disease, 23 cases (28.1%) had the hydatid cyst with a diameter of >10 cm. The prevalence in males and females in the county was 5.3% (40/753) and 9.4% (76/808), respectively (P<0.05). Among populations with different occupations, the highest prevalence of hydatid disease fell into houseworkers (11/61, 18.0%), monks (5/41, 12.2%) and herdsmen (84/758, 11.1%). Among the age groups, the groups of >60 years (24/132, 18.2%) and 30-40 years (31/302, 10.3%) had higher prevalence of hydatid disease. The three townships with the higher prevalence were Youyun (29/247, 11.7%), Changmahe (6/63, 9.5%) and Dangluo (54/645, 8.4%). Of the 199 samples of dog's feces, 54 were positive for Echinococcus antigens (27.1%), with a positive rate of 40.4% (23/57) in Youyun towship, being significantly higher than in the other two (P<0.05). CONCLUSION: Maqin county is a co-endemic area of cystic echinococcosis and alveolar echinococcosis. The prevalence is higher in females and those over 60 years-old.

[An epidemiological survey on echinococcosis in Zhiduo County of Qinghai Province].

The survey was carried out in July, 2006 in Zhiduo County. The IHA and ELISA positive rate in human population was 4.5% (42/933) and 8.2% (76/931) respectively. Ultrasonography revealed a morbidity of 3.4% (33/979) with 3.2% Echinococcus granulosus and 0.2% of E. multilocularis respectively. Animal dissection showed an infection rate of 15.1% (14/93) in pikas with one infected by E. shiquicus proved by molecular biology. Coproantigen rate by ELISA was 62% (12/193) in dogs and 35.7% (5/14) in wolves. The results indicated that Zhiduo County is a mixed endemic area for echinococcosis.

[Epidemiological survey on Echinococcus infection in animals in Qinghai Province].

Parasitological and dissection methods were used to confirm Echinococcus infection and echinococcosis in animals, and to understand the epidemiological situation in final and intermediate animal hosts in Qinghai Province. Three Echinococcus species were found in the Province including E. granulosus, E. multilocularis and E. shiquicus. The prevalence of hydatid disease showed a tendency of increase with an average rate of over 50% in yaks and sheep. Higher prevalence in wild animals as intermediate host was found in the southern plateau, while that in final hosts such as dogs and wolves, the prevalence was higher in the area of Qilian mountain. There is a complex chain of life cycle of the parasites among animals, which poses a threat to the health of human population. Effective measures to control the disease in animals are urgently needed.