Visible-Light-Induced Nickel-Catalyzed Cross-Coupling of Aryl Bromides with Nitriles.

Herein, a visible-light-induced nickel-catalyzed cross-coupling of aryl bromide with nitrile has been reported. By utilization of readily available nitriles as carbonyl precursors, a range of structurally diverse aryl ketones were facilely constructed. The synthetic simplicity, mild reaction conditions, and acidic functional group tolerance would broaden the synthetic utilities of this developed protocol as an expedient alternative to Grignard/organolithium protocols.

Photoexcited NiII-Aryl Complex-Mediated Giese Reaction of Aryl Bromides.

A Giese reaction of aryl bromides with electron-deficient alkenes was developed, enabled by a dual catalyst system containing NiII complex and IrIII photocatalyst. This protocol could accommodate a variety of aryl bromides and electron-deficient alkenes, delivering the conjugate adducts in up to 97% yield. The utilization of photoexcited (dtbbpy)NiII(aryl)Br intermediate as an aryl radical source allows this novel transformation of aryl halides, thus expanding the chemical space of excited nickel catalysis.

Exploration of animal models to study the life cycle of Fasciola hepatica.

The parasite Fasciola hepatica is an important zoonotic parasite. The development of an animal model of F. hepatica's life cycle is critical for studying the biological characteristics of the parasite in snails and mammals. Eggs of F. hepatica of bovine origin were cultured, and metacercariae were obtained after infection of Galba pervia snails. The life cycle system of F. hepatica was initiated in 2 different animals by orally infecting rabbits, SD rats and Kunming mice with the metacercariae. The animals' survival after infection, parasite migration in the animals and pathological damage to the liver were observed. We discovered that rabbits died due to acute suppurative hepatitis 60­69 days after infection, and eggs were found in the feces on day 63 of infection. The liver of SD rats showed punctate lesions on day 3 of infection, and further changes occurred as the infection progressed. However, liver repair was observed at week 9. SD rats survived for more than a year after infection and continued the F. hepatica life cycle. The liver lesions in Kunming mice after infection were similar but more severe than those in SD rats. Death was observed on the 31st post-infection day. We discovered that while rabbits, SD rats and Kunming mice can all be used as animal models of F. hepatica, SD rats are more suitable experimental animals in terms of tolerance and pathological response.

[Effects of moxibustion on the structure and function of blood brain barrier in Alzheimer's disease model rats].

OBJECTIVE: To investigate the effects of moxibustion on the structure and function of blood-brain barrier in Alzheimer's disease (AD) model rats. METHODS: Forty-eight SD rats were randomly divided into 4 groups: normal control group, sham operation group, model group, moxibustion group. Model group and moxibustion group rats were injected with aggregated Aß25-35 by bilateral hippocampus. In the rat model, the sham-operated group was injected with the same amount of normal saline in the bilateral hippocampus, and the normal group was not treated. After successful modeling, the moxibustion treatment was given at 2～3 cm above the Baihui, Shenshu and Yintang points of the moxibustion group rats, each time for 10 min, once a day, continuous treatment for 21 d. The Morris water maze test was used to evaluate the learning and memory ability of rats in each group. The Evans blue method was used to detect the permeability of blood-brain barrier. The ultrastructure of blood-brain barrier was observed under electron microscope. The matrix metalloproteinase 2 (MMP-2) and matrix metalloproteinase 9 (MMP-9) positive cells in hippocampus were detected by immunohistochemistry. RESULTS: Compared with the sham operation group, the escape latency was significantly increased (P＜0.01), and the space exploration time was decreased (P＜0.01), the learning and memory function in model group was impaired seriously, the Evans blue content in the brain was increased significantly (P＜0.01), the perivascular edema became larger, and the blood-brain barrier structure function was impaired. At the same time, the positive expressions of MMP-2 and MMP-9 in hippocampus were increased significantly (P＜0.01). Compared with model group, the learning and memory ability in moxibustion group rats was enhanced (P＜ 0.05), the content of Evans blue in the brain was decreased (P＜0.05), the degree of perivascular edema was reduced, and the damage of blood-brain barrier was improved. Positive expressions of MMP-2 and MMP-9 in hippocampus were decreased (P＜0.05 or P＜ 0.01). CONCLUSION: Moxibustion can decrease the expressions of MMP-2 and MMP-9, and reduce the damage of the structure and function of blood-brain barrier, thereby improving the learning and memory ability of AD model rats, and exerting therapeutic effects.

[Effect of comprehensive schistosomiasis control measures based on infection source control in mountainous areas of Yunnan Province].

OBJECTIVE: To evaluate the effect of comprehensive schistosomiasis control measures based on infection source control in plateau mountain areas of Yunnan Province. METHODS: From 2006 to 2004, four administrative villages were selected as test areas from plateau canyon and plateau basin endemic areas in Jindun Town, Heqing County, two villages each type, and the comprehensive control measures were implemented, including the examination and treatment of schistosomiasis, Oncomelania hupensis snail survey and control, health education, improving drinking water and lavatories, banning grazing, constructing sanitary pen of livestock, replacing cattle with machine, etc. The schistosome infection state and snail status in 2006 were treated as the baseline information, and the effect of the comprehensive measures were evaluated. Results The infection rate of human in plateau canyon areas decreased from 4.94% in 2006 to 0.06% in 2014, and that of livestock decreased from 1.11% to 0. In plateau basin areas, there was only 1 case of schistosomiasis found in Xiaolian Village in 2007, and no any other cases found in the other years, the infection rates of livestock dropped from 7.38% to 0. Compared with 2006, the snail areas in the two type areas decreased by 74.89% and 75.30%, respectively, meanwhile, the percentage of snail area, the occurrence rate of frames with snails, as well as the average density of living snails also decreased, and no infected snails were found since 2008. Xidian and Xinzhuang villages in plateau canyon area reached the criteria of schistosomiasis transmission controlled in 2009, and Xiao-lian and Kangfu villages in plateau basin reached the criteria of transmission interrupted in 2014. CONCLUSIONS: The comprehensive schistosomiasis control measures based on infection source control can effectively control the endemic situation of schistosomiasis in plateau areas of Yunnan Province. In the future, we should pay an equal attention to the infection sources control and snail control to consolidate and amplify the achievement of schistosomiasis control.

[Experimental infection of Galba pervia, Radix swinhoei and Physa acuta with Fasciola hepatica in Dali, Yunnan].

OBJECTIVE: To determine the intermediate host of Fasciola hepatica in Dali of Yunnan Province, and investigate its development and characteristics. METHODS: F. hepatica eggs from cattle were collected from July 2012 to July 2013, and placed in 28 degrees C water bath for incubation. Galba pervia, Radix swinhoei, and Physa acuta were collected from Dali, and used to be infected with F. hepatica in the laboratory. Trematode infections were excluded from the snails before experiment. All the snails were infected with F. hepatica miracidia, reared in mud pots. Dead snails were dissected for observing the development of F. hepatica. The metacercariae were collected and identified by PCR amplification of partial sequence of mitochondrial cytochrome oxidase subunit I (COX1) gene. RESULTS: A total of 1 146 R. swinhoei, 996 P. acuta, and 3 307 G. pervia snails were infected with F. hepatica, respectively. Mother rediae were found in two R. swinhoei snails, but no child rediae were observed in the snails. No larval forms were found in P. acuta. G. pervia was infected by F. hepatica with an infection rate of 27.2% (900/3307). The miracidium escaped from the egg and penetrated into G. pervia at temperature 22 degrees C, developed into a sporocyst after 7-15 days, which transformed into mother redia at the 11 st-20th day post-infection. The mother redia developed into daughter redia at the 30th-37th day, and produced cercaria with longtail, and became metacercaria at the 42nd-55th day. PCR confirmed that the metacercariae were that of F. hepatica, with an obvious band (approximately 500 bp). CONCLUSION: Among the three potential intermediate hosts in Dali, G. pervia is experimentally infected with F. hepatica.

[Molluscicidal effect of WPN and MNSC on Lymnaea].

OBJECTIVE: To evaluate the molluscicidal effect of wettable powder of 50% niclosamide ethanolamide salt (WPN) and suspension concentrate of 26% metaldehyde and niclosamide (MNSC) on Lymnaea. METHODS: WPN and MNSC were prepared as a series of solutions containing the active ingredient concentrations of 0.06, 0.13, 0.25, 0.50, 1.00, 2.00 mg/L and 4.00 mg/L, and the adult Lymnaea snails were soaked in the above mentioned series of solutions in the laboratory, and the LC50 values were calculated. The doses of active ingredient concentrations of 0.03, 0.06, 0.13, 0.25, 0.50, 1.00 g/m2 and 2.00 g/m2 of WPN and MNSC were adopted to spray on Lymnaea snails in the laboratory, and the LC50 values were calculated. A series of solutions containing the active ingredient concentrations of 1.00 mg/L, 0.50 mg/L, 0.25 mg/L, and 0.13 mg/L of WPN and MNSC were prepared, and the adult Lymnaea snails were put into the bowls with each concentration solution above mentioned and the climbing situation of the snails was observed at different time. RESULTS: By the immersion method, LC50 values of WPN at 48 h and 72 h were 0.93 mg/L and 0.64 mg/L respectively; LC50 values of MNSC at 48 h and 72 h were 0.74 mg/L and 0.51 mg/L respectively; by the spray method, when active ingredient concentrations of WPN and MNSC were 1.00 g/m2 or more, the death rates were both 100% after 3 days. In the climbing test, the Lymnaea snails did not climb in the solutions containing the active ingredient concentration of 1.00 mg/L of WPN and MNSC, however, a few snails climbed in the low concentrations. CONCLUSIONS: WPN and MNSC both have the effect of killing Lymnaea snails and inhibiting their climbing. By using the immersion method in the field, the active ingredient concentration of 2.00 mg/L of WPN and MNSC for 48 h is appropriate; by using the spray method, the active ingredient content of 1.00 g/m2 of WPN and MNSC for 3 days is appropriate.

[Investigation on Taenia sp. infection in Midu County of Yunnan Province].

The current status and species of Taenia sp. were investigated in Midu County by sedimentation method to examine eggs of Taenia sp. in stool, questionnairing as well as deworming by areca-pumpkin seeds in October-December, 2010. The infection rate of Taenia sp. was 15.7% (65/414). Among the positives, it was fairly high in the age groups of 40- and 50-, being 24% (21/85) and 26% (15/57), respectively. 26 cases with positive stool examination and 47 cases with a history of discharging proglottids were treated. Adult worms were collected from all 26 egg positive cases and 23 persons discharging proglottids. The highest number of adult worms expelled was 11 in a woman, 2 worms from another villager, but only one worm each from all other cases. 15 tapeworms with scolex and mature proglottids were examined and morphologically identified as T. asiatia. The high prevalence was related to the residents' dietetic habits (eg. eating raw pork and liver) , behaviour (eg. defecating in field) , and the egg-contaminated environment (eg. by untreated feces).

[Effect of comprehensive control and management of schistosomiasis at plateaus regions in Yunnan Province].

OBJECTIVE: To evaluate the effect of comprehensive control and management of schistosomiasis at plateaus regions in Yunnan Province. METHODS: Xiaolian and Kangfu villages at plateaus regions where schistosomiasis was endemic were selected as study areas from 2006 to 2011, the schistosomiasis comprehensive control measures were conducted, and these measures included the health education, chemotherapy, stool and water management, grazing forbidden, Oncomelania snail control, etc. combined with the infrastructure of farmland water conservancy, agricultural comprehensive development, adjustment of industry structure, returning farmland to forest, ditch hardening, and aquaculture. RESULTS: At Xiaolian Village, no schistosomiasis patient and livestock were found from 2008; and at Kangfu Village, no schistosomiasis patient was detected from 2006 and no schistosomiasis domestic animal was found from 2008. In 2011, the snail area, percent of frames with living snails, the number of snails, average concentration of living snails, and the highest concentration of living snails descended by 69.99%, 81.86%, 88.86%, 89.71%, 57.95% at Xiaolian Village, and descended by 27.65%, 1.11%, 94.71%, 92.16%, 88.00% at Kangfu Village, respectively, compared with those in 2006. The ratios of infected snail area to snail area were 68.91% in 2006 and 69.13% in 2007 at Xiaolian Village, and 61.73% in 2006 and 43.24% in 2007 at Kangfu Village. There were no infected snails from 2008 in the two villages. CONCLUSION: The comprehensive control and management measures can effectively control the schistosomiasis prevalence at plateaus regions.

[Investigation on outbreak of angiostrongyliasis cantonensis due to consumption of snail food in Dali City].

OBJECTIVE: To investigate the potential cause of an outbreak of eosinophilic meningitis in Dali City in March, 2011. METHODS: A retrospective investigation was performed among 18 consumers who had meal together. The clinical documents of inpatients were analyzed and the diagnoses were checked. The outpatients were investigated through a case survey. Pomacea snails on sale were examined for the infection status of Angiostrongylus cantonensis. RESULTS: Of 18 persons, 16 consumed Pomacea snail food and 9 were infected with an infection rate of 56.3%. The two persons who did not consumed snail food were not infected. Serum samples of seven patients were examined for antibody to Angiostrongylus cantonensis in peripheral blood and 3 were proved positive (42.9%). The snails consumed by the patients came from the market, and the surveillance data showed that the infection rate of Angiostrongylus cantonensis of Pomacea snails was 7.3%. CONCLUSION: According to the epidemiological survey, clinical manifestations, and laboratory examinations, the outbreak of eosinophilic meningitis is due to the consumption of Pomacea snails infected with Angiostrongylus cantonensis.