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Schistosomiasis has been subjected to extensive control efforts in the People's Republic of China (China) which aims to eliminate the disease by 2030. We describe baseline results of a longitudinal cohort study undertaken in the Dongting and Poyang lakes areas of central China designed to determine the prevalence of Schistosoma japonicum in humans, animals (goats and bovines) and Oncomelania snails utilizing molecular diagnostics procedures. Data from the Chinese National Schistosomiasis Control Programme (CNSCP) were compared with the molecular results obtained.
Sixteen villages from Hunan and Jiangxi provinces were surveyed; animals were only found in Hunan. The prevalence of schistosomiasis in humans was 1.8% in Jiangxi and 8.0% in Hunan determined by real-time polymerase chain reaction (PCR), while 18.3% of animals were positive by digital droplet PCR. The CNSCP data indicated that all villages harboured S. japonicum-infected individuals, detected serologically by indirect haemagglutination assay (IHA), but very few, if any, of these were subsequently positive by Kato-Katz (KK).
Based on the outcome of the IHA and KK results, the CNSCP incorporates targeted human praziquantel chemotherapy but this approach can miss some infections as evidenced by the results reported here. Sensitive molecular diagnostics can play a key role in the elimination of schistosomiasis in China and inform control measures allowing for a more systematic approach to treatment.
Schistosomiasis in China has been substantially reduced due to an effective control programme employing various measures including bovine and human chemotherapy, and the removal of bovines from endemic areas. To fulfil elimination targets, it will be necessary to identify other possible reservoir hosts for Schistosoma japonicum and include them in future control efforts. This study determined the infection prevalence of S. japonicum in rodents (0–9·21%), dogs (0–18·37%) and goats (6·9–46·4%) from the Dongting Lake area of Hunan province, using a combination of traditional coproparasitological techniques (miracidial hatching technique and Kato-Katz thick smear technique) and molecular methods [quantitative real-time PCR (qPCR) and droplet digital PCR (ddPCR)]. We found a much higher prevalence in goats than previously recorded in this setting. Cattle and water buffalo were also examined using the same procedures and all were found to be infected, emphasising the occurrence of active transmission. qPCR and ddPCR were much more sensitive than the coproparasitological procedures with both KK and MHT considerably underestimating the true prevalence in all animals surveyed. The high level of S. japonicum prevalence in goats indicates that they are likely important reservoirs in schistosomiasis transmission, necessitating their inclusion as targets of control, if the goal of elimination is to be achieved in China.
Palmer amaranth resistance to acetolactate synthase (ALS)–inhibiting herbicides was first identified in Georgia in 2000. Since then, complaints from peanut producers have increased concerning failure of ALS herbicides in controlling Palmer amaranth. Because efficacy of ALS herbicides can be compromised under adverse conditions, seeds from Palmer amaranth plants that escaped weed control were collected across the peanut-growing region in Georgia to investigate the cause of these reported failures. Greenhouse and growth-chamber studies were conducted using these seeds to evaluate whether weed escapes were a result of Palmer amaranth resistance to ALS herbicides. Each of the 61 accessions collected across Georgia exhibited varying levels of resistance to imazapic applied POST (< 55% control, relative to ALS-susceptible Palmer amaranth). Subsamples of the accessions were evaluated for their response to imazapic rates, which indicated variable levels of resistance across Palmer amaranth accessions. The rate of imazapic that provided 50% reduction in Palmer amaranth plant biomass (I50) for the known susceptible biotype was 0.9 g/ha of imazapic. Of the 10 accessions evaluated, 8 of them had I50 values that ranged from 3 to 297 g/ha of imazapic. The other two accessions could not be fit to the log-logistic dose–response curve and had undeterminable I50 values because of high levels of ALS resistance (> 1,400 g/ha of imazapic). Herbicide cross-resistance experiments indicated that 30 accessions were resistant to the ALS herbicides imazapic, chlorimuron, pyrithiobac, and diclosulam at the recommended field-use rates. However, each of these 30 accessions was susceptible to glyphosate. These data demonstrate that ALS-resistant Palmer amaranth occurs throughout the peanut-growing region of Georgia. Growers in Georgia will need to alter their weed-control programs in peanut to include herbicides with multiple modes of action that do not rely on ALS herbicides for effective Palmer amaranth control.
During 1990 we surveyed the southern sky using a multi-beam receiver at frequencies of 4850 and 843 MHz. The half-power beamwidths were 4 and 25 arcmin respectively. The finished surveys cover the declination range between +10 and −90 degrees declination, essentially complete in right ascension, an area of 7.30 steradians. Preliminary analysis of the 4850 MHz data indicates that we will achieve a five sigma flux density limit of about 30 mJy. We estimate that we will find between 80 000 and 90 000 new sources above this limit. This is a revised version of the paper presented at the Regional Meeting by the first four authors; the surveys now have been completed.
The 2013 multistate outbreaks contributed to the largest annual number of reported US cases of cyclosporiasis since 1997. In this paper we focus on investigations in Texas. We defined an outbreak-associated case as laboratory-confirmed cyclosporiasis in a person with illness onset between 1 June and 31 August 2013, with no history of international travel in the previous 14 days. Epidemiological, environmental, and traceback investigations were conducted. Of the 631 cases reported in the multistate outbreaks, Texas reported the greatest number of cases, 270 (43%). More than 70 clusters were identified in Texas, four of which were further investigated. One restaurant-associated cluster of 25 case-patients was selected for a case-control study. Consumption of cilantro was most strongly associated with illness on meal date-matched analysis (matched odds ratio 19·8, 95% confidence interval 4·0–∞). All case-patients in the other three clusters investigated also ate cilantro. Traceback investigations converged on three suppliers in Puebla, Mexico. Cilantro was the vehicle of infection in the four clusters investigated; the temporal association of these clusters with the large overall increase in cyclosporiasis cases in Texas suggests cilantro was the vehicle of infection for many other cases. However, the paucity of epidemiological and traceback information does not allow for a conclusive determination; moreover, molecular epidemiological tools for cyclosporiasis that could provide more definitive linkage between case clusters are needed.
Gliomas are neoplasms derived from glial cell precursors. Gliomas may present with one or a combination of neurological deficits, symptoms of mass effect and seizures, usually reflecting the anatomical location of the lesion. Seizures in the context of glioma appear to confer a significant prognostic benefit. Epileptic foci are believed to develop within the cortex surrounding tumors, since the lesions themselves have no electroencephalographic (EEG) activity and are not electrically excitable. Diagnosis of a space-occupying lesion as the cause of a seizure is made usually with the aid of cross-sectional imaging. Magnetic resonance imaging (MRI), with and without gadolinium contrast, is the investigation of choice, showing a higher sensitivity and specificity than computed tomography (CT) for detecting glioma. Fractionated focal radiotherapy is a key component of adjuvant treatment, especially in high-grade lesions. Chemotherapy with temozolomide has been shown to be of seizure benefit in approximately 50% of Grade 2 gliomas.
Environmental perturbations during early mammalian development can affect aspects of offspring growth and cardiovascular health. We have demonstrated previously that maternal gestational dietary protein restriction in mice significantly elevated adult offspring systolic blood pressure. Therefore, the present study investigates the key mechanisms of blood pressure regulation in these mice. Following mating, female MF-1 mice were assigned to either a normal-protein diet (NPD; 18 % casein) or an isocaloric low-protein diet throughout gestation (LPD; 9 % casein), or fed the LPD exclusively during the pre-implantation period (3·5 d) before returning to the NPD for the remainder of gestation (Emb-LPD). All offspring received standard chow. At 22 weeks, isolated mesenteric arteries from LPD and Emb-LPD males displayed significantly attenuated vasodilatation to isoprenaline (P = 0·04 and P = 0·025, respectively), when compared with NPD arteries. At 28 weeks, stereological analysis of glomerular number in female left kidneys revealed no significant difference between the groups. Real-time RT-PCR analysis of type 1a angiotensin II receptor, Na+/K+ ATPase transporter subunits and glucocorticoid receptor expression in male and female left kidneys revealed no significant differences between the groups. LPD females displayed elevated serum angiotensin-converting enzyme (ACE) activity (P = 0·044), whilst Emb-LPD males had elevated lung ACE activity (P = 0·001), when compared with NPD offspring. These data demonstrate that elevated offspring systolic blood pressure following maternal gestational protein undernutrition is associated with impaired arterial vasodilatation in male offspring, elevated serum and lung ACE activity in female and male offspring, respectively, but kidney glomerular number in females and kidney gene expression in male and female offspring appear unaffected.
In the sea, heterotrophic bacteria and other micro-organisms oxidize dissolved organic material. This process is important to the seasonal biological cycle of matter there because it is responsible for the return of an appreciable fraction of the inorganic nutrients (Andrews & Williams, 1971). It is also important in the process whereby the sea purifies itself of added dissolved organic pollutants: domestic and industrial wastes and spillages. These two processes, especially the latter, pose important and unanswered questions. One in particular is the behaviour of these heterotrophic populations when subjected to sudden increases in the concentration of an organic substrate. This will occur to some degree under natural conditions in sea water during or after a phytoplankton bloom and will occur to a considerable degree when pollutants are run into the sea.
The one-dimensional 1×1 and 1×2 tunnel structures of manganese dioxides, pyrolusit(β-MnO2) and ramsdellite (R-MnO2), respectively, were chemically intercalated with LiI. Two 7Li resonances were observed in lithiated pyrolusite. One isotropic resonance arising at 110 ppm shows a short spin-lattice relaxation time (T1 ∼ 3 ms) and was assigned to Li+ ions in the 1×1 tunnel structure. The other isotropic resonance arising at 4 ppm shows a long spin-lattice relaxation time (T1 ∼ 100 ms) and was assigned to Li+ ions in diamagnetic local environments in the form of impurities such as Li2O or on the surface of the MnO2 particles. Three 7Li resonances were observed in lithiated ramsdellite at very different frequencies (600, 110 and 0 ppm). The resonance at 600 ppm, which is observed at low lithium intercalation levels, is assigned toLi+ ions coordinated to both Mn(III) and Mn(IV) ions in the 1×2 tunnels, while the resonanceat 110 ppm is due to Li+ ions coordinated to Mn(III) ions and appears at higher Li levels. The resonance at 0 ppm is associated with a long spin-lattice relaxation time (T1 ∼ 100 ms) and is also assignedto Li+ ions in diamagnetic impurities.