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Protective effects of several amino acid-nutrients on gastric hemorrhagic erosions in acid-irrigated stomachs of septic rats.

Our previous report demonstrates that severe gastric mucosal damage is produced in lipopolysaccharide (LPS)-intoxicated rats. In the present study, we examined protective effects of several amino acids including taurine, phenylalanine and L-Arginine on gastric hemorrhagic erosions in acid-irrigated stomachs of LPS rats. The animals were deprived of food for 24 hr. Intravenous LPS (3 mg/kg) was challenged 12 hr after withdrawal of food. Gastric vagotomy was performed, followed by irrigation the stomachs for 3 hr with a physiological acid solution containing 100 mM HCl and 54 mM NaCl. The ulcerogenic parameters including increased gastric acid back-diffusion, mucosal histamine concentrations, lipid peroxide productions, luminal hemoglobin contents, stomach erosions and the lowered glutathione levels were markedly enhanced in LPS rat stomachs irrigated with acid solution. Both phenylalanine and taurine caused dose-dependent attenuations of these ulcerogenic parameters in LPS rats. L-arginine also was effective in inhibition. The inhibitory effect was restored by pretreatment of nitric oxide synthase inhibitors, such as N(G)-nitro-L-arginine-methyl ester or L-N(G)-(1-iminoethyl)-lysine. Furthermore, marked amelioration of hemorrhagic erosions in LPS rats was observed when a combination of these amino acid nutrients was used. The results provide evidence that these amino acid nutrients may ameliorate gastric hemorrhagic erosion via GSH synthesis stimulation, histamine cell membrane stabilization and antioxidant actions in LPS rat stomachs.

Acids↗

Secondary wastewater disposal for crop irrigation with minimal risks.

A critical objective for any wastewater reuse program is to close the gap between supply of and demand for water and to minimize health and environmental hazards. Thus, the effects of treated effluent on crops, soils and community health must be considered carefully. When applying wastewater to soil-plant systems, it is to be noted that the passage of water through the soil reduces considerably the number of microorganisms carried out by the reclaimed wastewater. Nevertheless, there is a need to study the real rate of organism decay subject to water quality, soil and vegetable characteristics, and irrigation method. The aim of this work is to determine the fate of the fecal coliforms, coliphages F+ and CN13, and helminth eggs survival during the application of reclaimed wastewater in a vineyard orchard near the City of Arad (Israel) via onsurface and subsurface drip irrigation systems. Wastewater obtained from a stabilization pond, and soil samples were tested and an important decrease of microorganisms was reached in both cases, with the better values obtained with the sub-surface drip irrigation system.

Agriculture↗

Climatic effects on Salmonella survival in plant and soil irrigated with artificially inoculated wastewater: preliminary results.

The use of wastewater to replace other water resources for irrigation is highly dependent on whether the health risk and environmental impacts entailed are acceptable or not. Total count and species of microorganisms found in wastewater vary widely because of climatic conditions, season, population sanitary habits and disease incidence. Salmonella, one of the genera associated with waterborne diseases, lives in the intestine. Thus, it is widely accepted that they have a limited survival period under environmental conditions. Wastewater management practices and the ability of Salmonella to survival under field conditions would determine the health risk associated with its presence in wastewater. Although chlorination is widely used, there are situations in which Salmonella is able to survive the sudden stress imposed by this technique. The aim of this experiment was to contribute to the study of the climatic and soil effects on pathogen survival under agricultural field conditions in order to assess which were the best wastewater management practices from both health and economic points of view. Five pots filled with soil seeded with Medicago sativa and an automatic weather station were used. A secondary effluent was artificially inoculated with Salmonella. In addition, open plates (filled with sterilised soil) and ultraviolet radiation isolated plates (filled with non-sterilised soil) were used. As soil heat emission contributes to the environmental conditions around the bacteria, standardised meteorological temperature data had to be carefully used in the bacterial survival studies under agricultural conditions. Radiation was the main cause of Salmonella mortality as its effect was more important than natural soil bacteria competence. Higher reduction of Salmonella counts could have been associated with longer spring days. Soil was able to effectively remove Salmonella. Subsurface drip irrigation methods could provide an effective tool to prevent health risk associated with wastewater irrigation.

Agriculture↗

Evaluation of impact of sewage irrigation on cytotoxicological potentialities of Chenopodium album in Allium assay.

Chenopodium album is a weed commonly consumed by North Indian population as vegetable. Plants are known to accumulate toxins from their environment. Presently, the leaf homogenates of these plants growing in a tubewell irrigated field and a sewage irrigated field were evaluated for cytotoxicological effects in Allium root tip assay. Studies revealed that Chenopodium album was mildly mitodepressive in nature and was capable of inducing chromosomal aberrations. The leaf homogenate of the plants growing in sewage irrigated fields induced more quantum of aberrations than the plants from the control site. This has a direct bearing on consumability of sewage grown vegetables and fodder.

Agriculture↗

[Runoff loss ways of nutrients in non-irrigated farmland in Hefei outskirts].

Taking non-irrigated flatlands in Hefei outskirts as experiment observation areas, yellow brown soil as selected soil type, and < 3 degrees as ground slope, the time of runoff development, runoff quantities, and silt carrying capacity under different rainfall intensity were observed on the non-irrigated farmlands with different kinds of crops such as grain, oil, cotton and vegetables, and with different coverage for continuous 3 years. Based on the observation, water and soil samples were collected and analyzed. The results showed that the loss way of the surface soil and nutrients in non-irrigated flatlands was obviously different from that on the sloping fields and on the upland. Over 98% of available N, P, and K nutrient loss were run off by chemical erosion. Physical erosion was the main way of the surface soil and organic matter loss, and 96.14% of total organic loss was caused by physical erosion.

Ecology↗

[Water distribution and microclimatic effects of sprinkler irrigation on spring wheat field].

Measurements of sprinkler irrigation on spring wheat field indicated that spring wheat canopy could intercept water by 25-30%, and compared with that above canopy in first milking period, the uniformity coefficient below canopy could be increased by 7-9%. Floating and evaporation loss of sprinkler irrigation water could reach 20-25% of the total. In addition, sprinkler irrigation on spring wheat field could decrease air and soil temperature, and increase air actual vapor pressure and relative humidity, which played a definite role in restraining crop transpiration.

Microclimate↗

Domestic wastewater treatment in waste stabilization ponds for irrigation in Mendoza, Argentina: policies and challenges.

Arid areas call for imaginative water management solutions to avoid the dangers of water shortages. Growing demands of water for domestic and industrial uses decrease the availability of water for agriculture. It therefore becomes necessary to set up a policy for the use of domestic effluents. For the province of Mendoza, Argentina, with 1,500,000 inhabitants, a master plan was designed as of 1991 for the treatment of domestic effluents and subsequent disposal for irrigation. The guidelines set up by WHO for the use of wastewater in agricultural applications were taken into consideration. At present, the Province of Mendoza has available projects which are either complete, in execution or in the bidding process, entailing secondary treatment capacity with reuse of 320,000 cubic metres/day and an estimated possible irrigation area of 10,000 hectares. With this infrastructure, some strategic lines of action are recommended to establish a policy for the agricultural use of wastewater: (a) to program the use of treated wastewater to avoid discharges to irrigation flows; (b) to develop an institutional scheme for the efficient and safe use of these waters; and (c) develop scientific and technologic know-how to accompany the updated policies.

Agriculture↗

Nitrous oxide and ammonia fluxes in a soybean field irrigated with swine effluent.

In the United States, swine (Sus scrofa) operations produce more than 14 Tg of manure each year. About 30% of this manure is stored in anaerobic lagoons before application to land. While land application of manure supplies nutrients for crop production, it may lead to gaseous emissions of ammonia (NH3) and nitrous oxide (N2O). Our objectives were to quantify gaseous fluxes of NH3 and N2O from effluent applications under field conditions. Three applications of swine effluent were applied to soybean [Glycine max (L.) Merr. 'Brim'] and gaseous fluxes were determined from gas concentration profiles and the flux-gradient gas transport technique. About 12% of ammonium (NH4-N) in the effluent was lost through drift or secondary volatilization of NH3 during irrigation. An additional 23% was volatilized within 48 h of application. Under conditions of low windspeed and with the wind blowing from the lagoon to the field, atmospheric concentrations of NH3 increased and the crop absorbed NH3 at the rate of 1.2 kg NH3 ha(-1) d(-1), which was 22 to 33% of the NH3 emitted from the lagoon during these periods. Nitrous oxide emissions were low before effluent applications (0.016 g N2O-N ha(-1) d(-1)) and increased to 25 to 38 g N2O-N ha(-1) d(-1) after irrigation. Total N2O emissions during the measurement period were 4.1 kg N2O-N ha(-1), which was about 1.5% of total N applied. The large losses of NH3 and N2O illustrate the difficulty of basing effluent irrigation schedules on N concentrations and that NH3 emissions can significantly contribute to N enrichment of the environment.

Agriculture↗

Characterization and mass load estimates of organic compounds in agricultural irrigation runoff.

Investigations of agricultural chemicals in surface runoff typically target nutrients or specific pesticides; however, numerous other organic compounds are regularly applied to agricultural fields in pesticide formulations, irrigation water, soil amendments and fertilizers. Many of these compounds have toxicological significance. We conducted a broad spectrum analysis of surface runoff from individual irrigated agricultural fields in coastal southern California to characterize organic compounds amenable to analysis by gas chromatography-mass spectrometry and to estimate the mass flux of selected chemicals. Aqueous phase extracts contained several pesticides, as well as personal care product ingredients and pharmaceutically active compounds apparently derived from treated wastewater used for irrigation. Several compounds potentially associated with pesticide adjuvants were also present in aqueous phase extracts. Dissolved NOM constituents in water phase extracts included n-fatty acids, aliphatic alcohols and plant terpenoids. Tentatively identified compounds sorbed to suspended particles included pesticides, a fecal sterol, aliphatic and alicyclic hydrocarbons, aliphatic alcohols, aldehydes, and C14 and C16 n-fatty acids and fatty acid esters. Bicyclic and polycyclic aromatic hydrocarbons were identified in both aqueous and suspended particle phases. Constituent concentrations, including total suspended solids (TSS), varied over the course of the sampled events by up to an order of magnitude, and typically were not correlated with flow. Variation in sorbed organic compound concentrations often did not parallel those for TSS concentration. Mass load estimates were strongly influenced by the choice of sampling interval.

Agriculture↗

[Effect of sewage irrigation on wheat growth and its activate oxygen metabolism].

The effects of sewage irrigation on the seedling growth of wheat and its activate oxygen metabolism were studied by water cultivation experiments. The results showed that compared with control, the wheat under sewage irrigation was short and small, and its roots number, fresh/dry weight of stem or root, and content of soluble protein decreased drastically. The content of chlorophyll decreased, while the Cyta/Cytb and membrane lipid peroxidation were increased. The sensitivity of pigment content of wheat leaf undr sewage irrigation was in order of Chlorophyll b > Chlorophyll a > Carotenoid. Furthermore, the POD, SOD and CAT activities of the wheat went down in varying degrees, and the SOD was the most susceptible enzyme to waste water stress. In this paper, the activities of POD, SOD and CAT decreased in 19.1%-33.1%, 37.8%-47.8% and 30.2%-35.9%, respectively.

Catalase↗

[The clinical and microbiological evaluation of the efficacy of oral irrigation on the periodontal tissues of patients wearing fixed orthodontic appliances].

The aim of the present study has been the evaluation of the effectiveness of oral irrigation with or without toothbrushing and dental flossing, in individuals treated with fixed orthodontic appliances, on controlling the development of dental plaque and, hence, of gingivitis. Eight individuals with a good general and oral status have been chosen. Before the experimental period, they received instructions about oral hygiene with toothbrushing and dental flossing and then they have been monitored to verify they were doing well. At the time T0, the upper tooth have been banded, three Periodontal Indexes (Plaque Index according to Silness and Loe, Modified Gingival Index according to Lobene and Gingival Bleeding Index according to Ainamo and Bay) registered and subgingival plaque samples from the premolars' gingival sulcus collected in order to point out the total anaerobes bacterial counts, the rates of motile bacteria, spirochetes, Gram positive and Gram negative cocci and bacteria, by means of optical and dark field microscopy and of cultural methods. For their oral hygiene, the patients had to use, in the right side toothbrush and dental floss (Control 1), in the left side the oral irrigator alone (Test 1). One month later (time T1), the lower teeth have been banded, too. In the right side the patients had to use toothbrush and dental floss (Control 2), while in the left one they used the same devices as Control 2 plus the oral irrigator (Test 2). At the time T1 Periodontal Indexes and Microbiological analyses have been extended to all the four quadrants.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Role of wastewater irrigation in mosquito breeding in south Punjab, Pakistan.

Mosquito breeding within the wastewater irrigation system around the town of Haroonabad in the southern Punjab, Pakistan, was studied from July to September 2000 as part of a wider study of the costs and benefits of wastewater use in agriculture. The objective of this study was to assess the vector-borne human disease risks associated with mosquito species utilizing wastewater for breeding. Mosquito larvae were collected on a fortnightly basis from components of the wastewater disposal system and irrigated sites. In total, 133 samples were collected, about equally divided between agricultural sites and the wastewater disposal system. Overall, 17.3% of the samples were positive for Anopheles, 12.0% for Culex and 15.0% for Aedes. Four anopheline species, viz, Anopheles stephensi (84.3% of total anophelines), An. subpictus (11.8%), An. culicifacies (2.0%) and An. pulcherrimus (0.2%) were present, as were two species of Culex, viz, Cx. quinquefasciatus (66.5% of culicines) and Cx. tritaeniorhynchus (20.1%). Aedes were not identified to species level. The occurrence of different species was linked to particular habitats and habitat characteristics such as physical water condition, chemical water quality and the presence of fauna and flora. Anophelines and Aedes mosquitos were mainly collected during the month of July, while Culex were collected in September. The prevalence of established vectors of human diseases such as An. stephensi (malaria), Cx. tritaeniorhynchus (West Nile fever, Japanese encephalitis) and Cx. quinquefasciatus (Bancroftian filariasis, West Nile fever) in the wastewater system indicated that such habitats could contribute to vector-borne disease risks for human communities that are dependent upon wastewater use for their livelihoods. Wastewater disposal and irrigation systems provide a perennial source of water for vector mosquitos in semi-arid countries like Pakistan. Vector mosquitos exploit these sites if alternative breeding sites with better biological, physical, and chemical conditions are not abundant.

Agriculture↗

Encephalopathy and seizures induced by intravesical alum irrigations.

Hemorrhagic cystitis is a significant toxic effect of cyclophosphamide therapy. Continuous bladder irrigation of a 1% alum solution is a simple and generally safe method of chemical cautery to treat the bleeding urothelium. We report four cases of encephalopathy coincident with elevated aluminum levels as well as one patient who developed seizures while receiving continuous bladder irrigations with alum. All patients had significant renal insufficiency. We recommend the cautious use of alum irrigation in patients with renal impairment and monitoring of serum aluminum levels to prevent excessive accumulation and toxicity.

Administration, Intravesical↗

Determination of metals of toxicological significance in sewage irrigated vegetables by using atomic absorption spectrometry and anodic stripping voltammetry.

Soil and vegetable samples drawn from the fields being irrigated by the city sewage have been analysed for some toxic metals namely copper, iron, cadmium, lead and chromium using atomic absorption spectrometry and anodic stripping voltammetry. It has been found that these vegetables contain an appreciable amount of these metals per unit dry mass, which the general public is ingesting everyday. It is further seen from the differential results that the fields being irrigated with the sewage water for the last so many years till date as compared to the ones, irrigation of which was replaced with the tubewell water some ten years ago, that the content of toxic metals is much larger in the former case. The results and the gravity of the situation is discussed.

Cadmium↗

Water reuse for irrigation from waste water treatment plants with seasonal varied operation modes.

Irrigation periods are usually limited to vegetation periods. The quality requirements for treated wastewater for disposal and for reuse are different. The reuse of water for irrigation allows partly the reuse of the wastewater's nutrients (N and P). Outside the irrigation period the water must be treated for disposal, thus nutrient removal is often required in order to avoid detrimental effects on the receiving surface water body. Only wastewater treatment plants with different operation modes for different seasons can realise these requirements. The nitrification is the most sensitive biological process in the aerobic wastewater treatment process. At low water temperatures the nitrifying bacteria need several weeks to re-start full nitrification after periods without NH4-removal. Therefore it is necessary to develop options for waste water treatment plants which allow a fast re-start of the nitrification process. Based on theoretical considerations and computer simulations of the activated sludge treatment process, one possibility for implementing a wastewater treatment plant with different seasonal operation modes is evaluated.

Agriculture↗

Hybrid membrane systems for secondary effluent polishing for unrestricted reuse for agricultural irrigation.

Field experiments are in progress for secondary wastewater upgrading for unrestricted utilization for agricultural irrigation. The integrative approach of secondary effluent polishing is based on using a hybrid UltraFiltration (UF) and Reverse Osmosis (RO) membrane pilot system with a capacity of around 1 m3/hr. The UF effluent is used to feed the RO membranes. The RO permeate is subsequently applied for vegetable irrigation. Field results indicate the importance of the UF component in the removal of the organic matter and the pathogens that are still contained in the secondary effluent. Under specific conditions, when the dissolved solids content is relatively low, regarding sanitary and health aspects, the UF effluent can be applied for unrestricted irrigation. During the RO stage most nutrients are removed, allowing application of the effluent without jeopardizing the soil fertility and the aquifers. Preliminary economic assessment indicates that the extra cost for effluent polishing via the UF stage only is in the range of 5 to 15 US cents/m3. The extra cost for the RO stage is also assessed at 10 to 25 US cents/m3. The additional cost depends to a large extent on the quality of the incoming raw secondary effluent and local requirements of the command region.

Agriculture↗

Control of vectors and incidence of malaria in an irrigated settlement scheme in Sri Lanka by using the insect growth regulator pyriproxyfen.

An evaluation of pyriproxyfen as a larval control agent with the aim of reducing malaria vector populations and incidence of malaria was conducted in 12 villages in an irrigated settlement scheme in the dry zone of central Sri Lanka. In these villages, there are many pools in the beds of rivers, streams, and irrigation ditches during the dry season of the year. These are the major breeding places of the malaria vectors Anopheles culicifacies and An. subpictus. Collections of adult mosquitoes were carried out by using standard methods and parasitological data were collected by daily malaria clinics set up for the project and through the 2 government hospitals. All villages in the study area were under residual house spraying with lambdacyhalothrin water-dispersible powder. Using the 1st year's baseline data collection, the villages were stratified into 6 villages with high malaria incidence and 6 villages with low incidence. Within each group, 3 villages were randomly assigned for larval control by treating all the pools in the beds of rivers, streams, and irrigation ditches and agricultural wells with a granular formulation of the insect growth regulator pyriproxyfen at the rate of 0.01 mg active ingredient/liter. The field bioassays indicated that a single treatment of pyriproxyfen effectively inhibited the emergence of adult mosquitoes in the riverbed pools for a period of 190 days. The treatment caused significant reduction of the adult populations of An. culicifacies (78%) and An. subpictus (72%). Similarly, incidence of malaria was reduced in the treatment villages by about 70% (95% confidence interval 58-78%) compared with the controls. The conclusion is made that pyriproxyfen can be a very effective means of malaria control if all possible vector breeding places in the area can be located.

Animals↗

[Effects of irrigating solution of Sihuang on morphology and function of nasal mucosa following surgery for chronic sinusitis and nasal polyps].

OBJECTIVE: To investigate the effect of the irrigating solution of Sihuang (ISSH) given after endoscopic surgery for chronic sinusitis and nasal polyps. METHODS: ISSH was used to irrigate the operated sinus cavity for 4 weeks in 109 patients with chronic sinusitis and/or polyps treated by endoscopic surgery, and 0.9%; normal saline (NS) was given in the same manner in another 109 patients receiving ISSH for similar problems, and the effects of the irrigating solutions was compared. Before and 3 months after the surgery, respectively, 32 patients with sinusitis were selected from each group for saccharin test. The mucosa in the ostiomeatal complex region was examined by electron microscopy in 6 patients before, two weeks and one month after surgery, respectively. RESULTS: The total effective rate was not significantly different between the two groups, but the postoperative morphological and functional recovery of the nasal mucosa occurred earlier in ISSH than in NS group (P<0.05). The level of SIgA was similar between the two groups before treatment (P>0.05), whereas after ISSH treatment, the SIgA level was significantly elevated in the treated group. Mucociliary transport rate was similar between ISSH and NS groups before the surgery (3.14+/-1.05 mm/min vs 3.31+/-1.09 mm/min, P>0.05), but 3 month after the surgery, the mucociliary transport rate increased to 6.09+/-2.63 mm/min in ISSH group and 5.04+/-1.22 mm/min in NS group, showing significant difference between them. Under electron microscope, the cilia of the epithelial cells were found exfoliated preoperatively but regularly arranged after the surgery, presenting the "9+2" architecture of the microtubule. CONCLUSION: ISSH used after operation can improve the therapeutic effect of endoscopic surgery for chronic sinusitis and/or nasal polyps.

Adolescent↗