Comparative Assessment of Neutrophil Gelatinase-Associated Lipocalin (NGAL) and Cystatin C as Early Biomarkers for Early Detection of Renal Failure in Patients with Hypertension

Background:

Hypertension is one the most common causes of chronic kidney disease (CKD). One of the major concerns in hypertensive patients is early detection of renal disorders. In the past, serum creatinine (Scr) concentration was used as a marker of kidney function, but it proffers a late reflection of reduced glomerular filtration rate. Cystatin C and neutrophil gelatinase-associated lipocalin (NGAL) have been recently proven to be useful for quantification of CKD. Therefore, we compared the diagnostic value of NGAL with cystatin C and creatinine to evaluate kidney function in hypertensive patients.

Methods:

In this study, 42 hypertensive patients and 30 healthy volunteers were recruited. Serum cystatin C (Scys C) and plasma NGAL were measured using ELISA method. Creatinine, urea, hemoglobin, fibrinogen, and C-reactive protein were measured according to the routine methods. Estimated glomerular filtration rate (eGFR) was considered as the gold standard method (cut-off value of < 78 ml/min/1.73 m².

Results:

In the patient group, plasma NGAL, cystatin C, and creatinine were all significantly correlated with eGFR, and plasma NGAL correlated best with eGFR. Receiver-operating characteristics analysis indicated that plasma NGAL was a better indicator than creatinine and cystatin C for predicting a GFR < 78 ml/min/1.73 m². The sensitivity and specificity for NGAL were 96% and 100%, for cystatin C were 92% and 60% and for creatinine were 76% and 47%, respectively.

Conclusion:

Plasma NGAL demonstrated a higher diagnostic value to detect kidney impairment in the early stages of CKD as compared to Scys C and Scr in hypertensive patients.Key Words: Neutrophil gelatinase-associated lipocalin (NGAL), Cystatin C, Creatinine, Hypertension     

Development of an early warning system for brown planthopper (BPH) (<Emphasis Type="Italic">Nilaparvata lugens</Emphasis>) in rice farming using multispectral remote sensing

The spread of rice pests such as BPH in tropical areas is one of the best-known yield lost factors. Remote sensing can support precision farming practices for determining the location of spreads and using pesticide in the right place. In a specifically conducive environment like high temperature and heavy rainfall, BPH population will increase. To address this issue, detection of sheath blight in rice farming was examined by using SPOT-5 images. Also, the extraction of weather data derived from Landsat images for comparing with the BPH infestation was undertaken. Results showed that all the indices that recognize infected plants are significant at α = 0.01. Examination of the association between the disease indices indicated that band 3 (near infrared) and band 4 (mid infrared) in SPOT-5 images have a relatively high correlation for detecting diseased part from healthy ones. The selected indices declared better association for detecting healthy plants from diseased ones. Image investigations revealed that BPH were existing at the higher limits of tolerable temperatures when in the form of nymphs. With the knowledge that the late growth stage of plants has more severe BPH attacks, the results stated that BPH outbreak is particularly obvious in the north-west corner and middle regions of the maps and it is more likely to happen in specified ranges of temperature and RH, i.e. 29 °C <T< 32 °C, and 88 % <RH< 93 %.     

Determination of soybean yield gap and potential production in Iran using modeling approach and GIS

Increasing crop production is necessary to maintain food security for the growing global population.Reducing the gap between actual and potential yield is one of the important ways to increase yield per unit area.Potential yield and the yield gap of soybean were determined for Golestan Province,Iran,using Soybean Simulation Model (SSM-i Crop2) and Geographical Information System (GIS).Information from 24 weather stations and soil data of the region were used.Yield gap and production gap were calculated at county and province levels.The average actual yield of soybean in this province was2.28 t ha~(–1) while the province’s potential yield was 4.73 t ha~(–1),so the yield gap was estimated 2.44 t ha~(–1).Thus,there is a great potential for increasing soybean yield in Golestan,which is possible through improving crop management of soybean in farmers’fields.The average water productivity of soybean was estimated to be 0.81 kg m~(–3).Spatial distribution of water productivity in soybean farms showed that the highest and the lowest water productivities (0.99 and 0.44 kg m~(–3)) were in western and eastern regions of the province,respectively,in accordance to vapour pressure deficit.It was concluded that soybean production in the province could increase by 66%(from 109 970 to 182 170 tons) if 80% of the current yield gap could be removed.     

Effect of exogenous application of free polyamines on physiological disorders and yield of ‘Kaleh-Ghoochi’ pistachio shoots (Pistacia vera L.)

Pistachio trees exhibit some physiological disorders such as abscission of inflorescence buds, fruit abscission, the production of blank, non-split, early-split and deformed nuts. Since the occurrence of these disorders is closely related to the yield, the effect of free polyamine treatments on these disorders and the yield was investigated in two consecutive years (“on” and “off” years). Free polyamine treatments were applied one week before and also two weeks after full bloom. Results showed that Spermine (Spm), unlike Putrescine (Put), decreased the physiological disorders of pistachio and also increased the yield. Free polyamine treatments did not affect the percentage of early-split nuts. Spermidine (Spd) decreased the percentage of both fruit abscission and deformed nuts but did not affect the yield. In both the “on” and “off” years the effect of Spm and Spd was greatly dependent on both the time of application and the concentrations used. Results of free polyamine analysis showed that exogenous application of these compounds, especially two weeks after full bloom, increased the free polyamine contents of shoots in both “on” and “off” years confirming the absorption of free polyamines via spray application in pistachio crop. Exogenous application of Spm two weeks after full bloom decreased the abscission of inflorescence buds in “on” year supporting the idea that free polyamines could trigger the abscission process of inflorescence buds. Since Spm decreased the percentage of blank, non-split and deformed nuts, it seems that Spm dominantly plays a key role in the growth and development of pistachio nuts.     

In vitro polyploidy-mediated enhancement of secondary metabolites content in Stachys byzantina L.

Genetic Resources and Crop Evolution - Lamb’s-ear (Stachys byzantina L.) serves as valuable medicinal plant mainly because of its pharmaceutical phyto-metabolites like linalool. Polyploidy...     

Effects of plant residues and calcite amendments on soil sodicity

The effects of wheat, potato, sunflower, and rape residues and calcite were evaluated in soil that received sodic water. These materials were added to a sandy‐loam soil at a rate of 5%, after which the treated soils were incubated for 1 month at field‐capacity moisture and a temperature of 25°C–30°C. Column leaching experiments using treated soils were then conducted under saturated conditions using water with three sodium‐adsorption ratios (SAR) (0, 10, 40) with a constant ionic strength (50 mmol L^–1). The results indicated that the application of plant residues to soils caused an increase in cation‐exchange capacity and exchangeable cations. Leaching experiments indicated that the addition of plant amendments led to increased Na⁺ leaching and decrease in exchangeable‐sodium percentage (ESP). The ESP of the control soil, after leaching with solutions with an SAR of 10 and 40, increased significantly, but the level of sodification in soils treated with plant residue was lower. Such decreases of soil ESP were greatly affected by the type of plant residues, with the order of: potato‐treated soil > sunflower‐treated soil > rape‐treated soil > wheat‐treated soil > calcite‐treated soil > control soil.     

An epidemiological survey on bovine and ovine babesiosis in Kurdistan Province, western Iran

The aim of this study was to determine the prevalence of the Babesia infection in domestic animals in Kurdistan Province of Iran for the first time. In this survey, 9,111 domestic livestock, including cattle and sheep, were randomly sampled and examined from 500 flocks in Kurdistan Province from July 2007 to September 2009. Thin peripheral blood smears were taken and then stained by Giemsa staining method. From a total of 9,111 collected samples, 2,642 were sheep and 6,469 were cattle. Babesia spp. is detected in 1,359 (51.4%) out of sheep samples and 136 (2.1%) out of cattle samples by direct examination of blood smear. Altogether, the prevalence rate of Babesia infection was 16.4% (n = 1,495) in both animal groups. Babesia ovis and Babesia bigemina were the most prevalent species found in sheep and cattle, respectively. The relatively high prevalence of Babesia infection in livestock indicates the epizootic stability status of babesiosis in the western part of Iran.     

Rates of decomposition and phosphorus release from organic residues related to residue composition

The use of organic residues might be appropriate in maintaining long‐term P requirement of crops. Eight plant residues and two manures in a wide range of C : N ratios were incubated for 12 weeks at 25°C, during which the processes of decomposition and formation of acid‐extractable P (P release) were assessed. Residues were incubated moist in bags and inoculated with a soil suspension. The exponential model was found to be suitable to describe decomposition and P‐release rates from residues. There were two distinct parts of P release in each time curve, which gave two rate constants and were calculated as the slope of each part. The rates of P release of the residues were considerably higher during the first 4 weeks of incubation than during the second phase of incubation (weeks 5–12). Phosphorus release by residues was similar to the decomposition pattern. The residue P content was correlated with P release, but not with decomposition rate. Mass loss and release of P were greater from sunflower and wheat residues than from sheep manure, suggesting that a high C : N ratio does not necessarily retard decomposition. The model parameters of P release were derived which are suitable to estimate the P‐fertilizer effect of organic residues. Our results suggest that the use of organic residues as a source for short‐ and long‐term P supply for crops should be encouraged.