Antimicrobial Susceptibility of 41 Burkholderia mallei Isolates From Spontaneous Outbreaks of Equine Glanders in Punjab,Pakistan

Minimum inhibitory concentrations (MICs) of 20 antimicrobial agents for 41 isolates of Burkholderia mallei from natural outbreaks of equine glanders were determined by agar dilution. All isolates were intrinsically resistant to ampicillin (MIC₉₀ ≥128). Resistance to other antimicrobials was as follows: 95.1% to amoxicillin and cephradine, 85.4% to cefuroxime and norfloxacin, 68.3% to ceftizoxime and ceftriaxone, 61.1% to ceftiofur, 58.5% to oxytetracycline, 41.5% to ciprofloxacin, 58.5% to roxithromycin, 17.1% cefotaxime, and 12.2% clarithromycin. Overall resistance patterns revealed that 17% of isolates were simultaneously resistant to amoxicillin, cephradine, cefuroxime, ceftizoxime, ceftriaxone and norfloxacin. None of the isolates were resistant to amoxicillin-clavulanic acid, doxycycline, chloramphenicol, gentamicin or trimethoprim-sulphadiazine. Mode MICs for these antimicrobials were 2, 1, 8, 4 and 1 μg/ml, respectively. A majority of the isolates (∼ 94%) were susceptible to both enrofloxacin and ofloxacin. These data provide an updated perspective on susceptibility profiles of current strains of B. mallei in an endemic area.     

Development of molecular simulation methods to accurately represent protein-surface interactions: The effect of pressure and its determination for a system with constrained atoms

When performing molecular dynamics simulations for a system with constrained (fixed) atoms, traditional isobaric algorithms (e.g., NPT simulation) often cannot be used. In addition, the calculation of the internal pressure of a system with fixed atoms may be highly inaccurate due to the nonphysical nature of the atomic constraints and difficulties in accurately defining the volume occupied by the unconstrained atoms in the system. The inability to properly set and control pressure can result in substantial problems for the accurate simulation of condensed-phase systems if the behavior of the system (e.g., peptide/protein adsorption) is sensitive to pressure. To address this issue, the authors have developed an approach to accurately determine the internal pressure for a system with constrained atoms. As the first step in this method, a periodically extendable portion of the mobile phase of the constrained system (e.g., the solvent atoms) is used to create a separate unconstrained system for which the pressure can be accurately calculated. This model system is then used to create a pressure calibration plot for an intensive local effective virial parameter for a small volume cross section or "slab" of the system. Using this calibration plot, the pressure of the constrained system can then be determined by calculating the virial parameter for a similarly sized slab of mobile atoms. In this article, the authors present the development of this method and demonstrate its application using the CHARMM molecular simulation program to characterize the adsorption behavior of a peptide in explicit water on a hydrophobic surface whose lattice spacing is maintained with atomic constraints. The free energy of adsorption for this system is shown to be dramatically influenced by pressure, thus emphasizing the importance of properly maintaining the pressure of the system for the accurate simulation of protein-surface interactions.     

Identification and characterization of important sterile and maintainer lines from various genotypes for advanced breeding programmes of onion (Allium cepa)

Onion is one of the major vegetable crops in terms of production as well as consumption. In the current research, available onion genetic stock was evaluated to identify male-sterile lines and produce high-yielding F₁ hybrids for future breeding programmes. A mitochondrial DNA-based marker was mapped and correlated with phenotypic traits to isolate male-sterile plants. Based on the floral and pollen structure, nine putative male-sterile lines were identified. On the other hand, for nuclear marker identification at Ms locus, two sets of primers were used, one for Ms dominant allele and another for sterile and maintainer plants. Results revealed that 70% of open pollinated varieties (OPVs) possess plants with sterile cytoplasm coupled with genetic sterility at Ms locus, called sterile “A” line. Approximately 20% of plants in some genotypes were identified with normal (N) cytoplasm having recessive fertility gene at Ms locus, called maintainer “B” line. Based on the present findings, “A”, “B” and “R” (restorer line), future F₁ hybrid seed production systems in onion is discussed.     

Gibberellin producing Neosartorya sp. CC8 reprograms Chinese cabbage to higher growth

Gibberellins production by soil fungi received little attention, although substantial work has been carried out on other growth promoting aspects of soil borne fungi. We investigated gibberellins production and growth promoting capacity of a novel fungal strain of Neosartorya, which was isolated from the roots of Chinese cabbage (Bassica rapa L. ssp. pekinensis). Fungal culture filtrates (CF) obtained from pure cultures of 16 endophytic fungi were bioassayed on Waito-C, in order to investigate plant growth promoting capacity of these fungi. The fungal isolate CC-8 induced maximum shoot length of Waito-C (13.0 cm) as compared to control treatments. In a separate experiment, the CF of fungus CC-8 significantly promoted plant length and biomass of Chinese cabbage. The fungal CF also increased endogenous bioactive GA₁ and GA₄ contents of Chinese cabbage. Gibberellin analysis of CF of CC-8 showed presence of both physiologically active and non active gibberellins in higher concentrations (GA₁, 1.42 ng/ml; GA₃, 5.93 ng/ml; GA₄, 11.36 ng/ml; GA₇, 3.25 ng/ml; GA₉, 0.79 ng/ml; GA₁₅, 1.18 ng/ml). The culture filtrate of CC-8 produced higher amounts of GA₃, GA₄, GA₇ and GA₉ than wild type Fusarium fujikuroi, a well known gibberellins producing fungus. The fungal isolate CC-8 was later identified as a new strain of Neosartorya species on the basis of traditional and advance molecular techniques.     

Long-term manure application increased soil organic carbon and nitrogen mineralization through accumulation of unprotected and physically protected carbon fractions

Soil organic carbon(SOC) and nitrogen(N) mineralization are important biogeochemical processes associated with soil fertility. These processes are influenced by physically, chemically, and biologically stabilized SOC fractions, the mechanisms of which are not well known. The present study was conducted to evaluate the combined effect of manure and mineral fertilizers on the contents of SOC fractions to promote the mineralization of SOC and N.Treatments included: i) no fertilizer control(CK); ii)...     

A comparison of peat properties in intact,afforested and restored raised and blanket bogs

Recognition of peatlands as a key natural store of terrestrial carbon has led to new initiatives to protect and restore them. Some afforested bogs are being clear-felled and restored (forest-to-bog restoration) to recover pre-afforestation ecosystem function. However, little is known about differences in the peat properties between intact, afforested and restored bogs. A stratified random sampling procedure was used to take 122 peat cores from three separate microforms associated with intact (hollows; hummocks; lawns), afforested and restored bogs (furrows; original surface; ridges) at two raised and two blanket bog locations in Scotland. Common physical and chemical peat properties at eight depths were measured in the laboratory. Differences in bulk density, moisture and carbon content between the afforested (mean = 0.103 g cm⁻³, 87.8% and 50.9%, respectively), intact (mean = 0.091 g cm⁻³, 90.3% and 51.3%, respectively) and restored bogs (mean = 0.095 g cm⁻³, 89.7% and 51.1%, respectively) were small despite their statistical significance. The pH was significantly lower in the afforested (mean = 4.26) and restored bogs (mean = 4.29) than the intact bogs (mean = 4.39), whereas electrical conductivity was significantly higher (mean: afforested = 34.2, restored = 38.0, intact = 25.3 μS cm⁻¹). While significant differences were found between treatments, effect sizes were mainly small, and greater differences in pH, electrical conductivity, specific yield and hydraulic conductivity existed between the different intact bogs. Therefore, interactions between geographic location and land management need to be considered when interpreting the impacts of land-use change on peatland properties and functioning.     

A simple approach for regulating saline groundwater inflows to natural streams in irrigated agricultural areas

Stream salinity management is of prime importance for ensuring environmental sustainability of rivers, streams, lakes and other water bodies. Saline groundwater inflows are the main cause of deteriorating quality of stream flows; especially during periods of low flows. The Murray-Darling Basin is a good example for reducing groundwater recharge from irrigated agricultural areas with successful implementation of land and water management plans (LWMPs). In most cases, these plans help minimize the influence of saline groundwater flows on the stream salinity, as a preventive measure. As a remedial measure, this paper introduces a simple but an innovative approach for regulating saline groundwater inflows to natural streams in irrigated agricultural areas. The approach uses the flap gate with an automatic lowering and raising mechanism. During low stream flow, this gate is kept in a raised position. Depending upon the upstream inflows, the ponding situation will develop hydraulic gradient away from the stream; groundwater inflows to the creek will become minimal. During high stream flows, the gate is kept in a lower position to let the diluted water flows through the stream uninterrupted. To install, operate and manage such gates on multiple sites along the stream(s), the individual control panels can be joined into a central control station via telemetric link up. This approach, which holds a key for successfully regulating groundwater induced salinity to natural streams, should be considered in conjunction with other LWMPs to improve stream salinity in an irrigated agricultural area.     

Comparison of Nutritional Value,Antioxidant Potential,and Risk Assessment of the Mulberry (Morus) Fruits

Ethnomedicinal uses, chemical composition (major nutrients, essential/toxic metals, phytochemical constituents), and antioxidant properties of the fruits of five Morus species (M. alba, M. laevigata, M. macroura, M. nigra, and M. serrata) were evaluated in this study. Standard methodology was used for the analysis of the nutrients, major/trace metals, phytochemicals, and antioxidant potential of the fruits. Highest average contents of the proteins (13.1%), fats (12.4%), fibers (8.02%), and carbohydrates (80.5%) were found in M. macroura, M. laevigata, M. nigra, and M. serrata, respectively. Among the metals, highest concentration in the fruits was shown by K (1080–1230 mg/kg), followed by Mg (84.4–207 mg/kg), Ca (54.8–146 mg/kg), Fe (13.6–59.0 mg/kg), Na (5.43–14.8 mg/kg), and Zn (2.15–5.57 mg/kg). The phytochemicals and antioxidant activities were measured in the water and acetone extracts of the fruits. Relatively higher total phenolics (85.6 mg GAE/100 g, FW), flavonoids (85.8 mg RE/100 g, FW), flavonols (99.8 mg RE/100 g, FW), and ascorbic acid (4.12 mg AAE/100 g, FW) contents were found in M. nigra, which also revealed significantly higher 2,2-diphenyl-1-picrylhydrazyl (DPPH) inhibition (93.8%). Considerably higher OH radical and H₂O₂ scavenging activities were observed in M. macroura and M. alba, respectively. Comparatively higher ferrous ions chelating activity (37.8%) was noted in M. serrata, which also showed highest value for phosphomolybdenum assay (183 µM AAE/100 g, FW). Highest ferric ion reducing antioxidant power (69.9 µM GAE/100 g, FW) was found in M. leavigata. The Morus fruits were a good source of the nutrients, minerals, and phyotchemicals along with superior antioxidant potential. Health risk assessment showed no significant non-carcinogenic or carcinogenic health risk associated with the consumption of these fruits.     

Effect of varying ruminally degradable to ruminally undegradable protein ratio on nutrient intake, digestibility and N metabolism in Nili Ravi buffalo calves (Bubalus bubalis)

Four Nili-Ravi buffalo calves (100 ± 4 kg) were used in 4 × 4 Latin Square Design to evaluate the influence of varying ruminally degradable protein (RDP) to ruminally undegradable protein (RUP) ratio on dry matter intake (DMI), digestibility and nitrogen (N) metabolism. Four experimental diets A, B, C and D were formulated to contain RDP:RUP of 70:30, 65:35, 60:40 and 55:45, respectively. The calves were fed ad libitum. Dry matter intake by calves fed C diet was higher (P < 0.05) than those fed D diet and lower (P < 0.05) than calves fed A diet, however, it was similar to those fed B diet. There was a linear decrease (P < 0.01) in DMI with decreasing the RDP to RUP ratio. Similar trend was noticed in crude protein (CP) intake. Neutral detergent fiber (NDF) intake was significantly different across all treatment. The decrease in CP and NDF intake was due to decreasing trend of DMI. Dry matter (DM) digestibility in calves fed A and B diets was higher (P < 0.05) than those fed C and D diets. A linear decrease (P < 0.01) in DM digestibility was observed with decreasing the RDP to RUP ratio. Crude protein digestibility remained unaltered across all treatments. Neutral detergent fiber digestibility was higher in calves fed A and B diets than those fed C and D diets. Higher NDF digestibility in calves fed A and B diets was due to higher level of dietary RDP that might resulted in higher ruminal ammonia concentration which stimulate activity of cellulytic bacteria and ultimately increased NDF digestibility. The N retention (g/d) was similar among the calves fed B, C and D diets, however, it was higher (P < 0.05) than those fed A diet. Decreasing the RDP to RUP ratio resulted in linear increase (P < 0.01) in N retention. The N retention, as percent of N intake was significantly different across all treatments. Decreasing RDP to RUP ratio resulted in linear increase (P < 0.01) in N retention, as percent of N intake. A similar trend was noticed in N retention, as percentage of N digestion. Blood urea nitrogen (BUN) concentration in calves fed B diet was higher (P < 0.05) than those fed D diet and was lower (P < 0.05) than those fed A diet, however, it was not different from calves fed C diet. Decreasing dietary RDP to RUP ratio resulted in linear decrease (P < 0.05) in BUN concentrations. The decrease in BUN concentration was because of decreasing level of dietary RDP. The N retention can be increased by decreasing RDP to RUP ratio in the diet of growing buffalo calves and diet containing RDP to RUP ratio 55:45 is considered optimum regarding N retention in buffalo calves.