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Imaging is increasingly used to detect and monitor bacterial infection. Both anatomic (X-rays, computed tomography, ultrasound, and MRI) and nuclear medicine ([111In]-WBC SPECT, [18F]FDG PET) techniques are used in clinical practice but lack specificity for the causative microorganisms themselves. To meet this challenge, many groups have developed imaging methods that target pathogen-specific metabolism, including PET tracers integrated into the bacterial cell wall. We have previously reported the d-amino acid derived PET radiotracers d-methyl-[11C]-methionine, d-[3-11C]-alanine, and d-[3-11C]-alanine-d-alanine, which showed robust bacterial accumulation in vitro and in vivo. Given the clinical importance of radionuclide half-life, in the current study, we developed [18F]3,3,3-trifluoro-d-alanine (d-[18F]-CF3-ala), a fluorine-18 labeled tracer. We tested the hypothesis that d-[18F]-CF3-ala would be incorporated into bacterial peptidoglycan given its structural similarity to d-alanine itself. NMR analysis showed that the fluorine-19 parent amino acid d-[19F]-CF3-ala was stable in human and mouse serum. d-[19F]-CF3-ala was also a poor substrate for d-amino acid oxidase, the enzyme largely responsible for mammalian d-amino acid metabolism and a likely contributor to background signals using d-amino acid derived PET tracers. In addition, d-[19F]-CF3-ala showed robust incorporation into Escherichia coli peptidoglycan, as detected by HPLC/mass spectrometry. Based on these promising results, we developed a radiosynthesis of d-[18F]-CF3-ala via displacement of a bromo-precursor with [18F]fluoride followed by chiral stationary phase HPLC. Unexpectedly, the accumulation of d-[18F]-CF3-ala by bacteria in vitro was highest for Gram-negative pathogens in particular E. coli. In a murine model of acute bacterial infection, d-[18F]-CF3-ala could distinguish live from heat-killed E. coli, with low background signals. These results indicate the viability of [18F]-modified d-amino acids for infection imaging and indicate that improved specificity for bacterial metabolism can improve tracer performance.

Greenhouse tomato production is a growing business worldwide, and it is strongly promoted by bumblebee pollination. Although there are over 250 bumblebee species worldwide, very few species have been reared successfully for greenhouse tomato pollination. Those successfully managed species, especially Bombus terrestris, are shipped around the world for commercial use. However, managed bumblebees are known to escape greenhouse facilities, have established local populations, spread disease to local bumblebees, and are blamed for the declines of some indigenous bee species. An alternative to shipping exotic bumblebees around the world is to develop local species for greenhouse pollination. Such an approach has the dual benefits of creating a new industry of insect rearing while reducing threats to local bee communities. In this study, we successfully reared Bombus haemorrhoidalis, which is the most common bumblebee species in Northern Pakistan, in a laboratory and compared its effectiveness as a tomato pollinator with that of commercial B. terrestris in a greenhouse. We found that the effectiveness of B. haemorrhoidalis in tomato pollination in a greenhouse is very similar to that of B. terrestris when it comes to the fruit size, number of seeds, and fruit weight. Our study provides an example of how to rear a native bumblebee species to pollinate local crops, which is a method that could potentially substitute the importation of non-ingenious bumblebees. [ABSTRACT FROM AUTHOR]

The leaf worm, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) is a notorious insect pest of many economically important cultivated crops like cotton, maize, tobocco and vegetables causing severe economic losses from 50-100%. In most crops, damage arises due to voracious feeding by the larvae and leads to the skeletonizing of leaves. Toxicological studies were performed to estimate lethal and sublethal levels of flubendiamide and spirotetramat against S. litura. Effects of these estimated values were assessed on different biological traits of S. litura including life duration, survival and next generation potential. Both flubendiamide and spirotetramat showed toxic responses against second instar larvae of S. litura under laboratory conditions. Larval duration and survival rate of S. litura to were significantly different. Exposure to test insecticides resulted in negative effect on the demography of S. litura as longer life cycle and decreased fecundity. Changes in net reproductive rate and intrinsic rate of increase also helped to decide the fate of these insecticides. Low reproductive potential and low hatching percentage due to exposure to test insecticides can help to manage next generation of target pest. These two new chemistry insecticides can be recommended for their effective and long-term utilization against this important leaf feeder which may help its management and decrease economic losses faced by the growers. Their impact on larval duration and low survival rate at lethal levels guides about their potential in pest control. [ABSTRACT FROM AUTHOR]

Environmental pollution caused by synthetic fertilizers necessitates source and dose optimization of organic manures of animal origin for rainfed wheat accessions. A field trial was executed to determine the impact of chicken manure and farm yard slurry applied as sole sources of nutrients and in conjunction with chemical fertilizers on wheat accessions. Yield attributes, grain yield (Gy), biological yield (By) and harvest index (Hi) of wheat were recorded as response variables. Wheat (cv. NARC-2009) under chemical fertilizers alone remained unmatched in terms of yield attributes along with Gy (4.32 t ha-1), By (9.85 t ha-1) and Hi (44%). The same accession under co-application of chicken manure and chemical fertilizers followed it with Gy of 4.08 t ha-1, which in turn was followed by coa-application of farm yard slurry and chemical fertilizers. The minimum Gy (2.94 t ha-1) was recorded by wheat (cv. Pakistan-2013) under no fertilization owing to significantly lesser peduncle and spike lengths, grains per spike, number of spikelets and 1000-grains weight. Thus, it can be inferred that wheat accessions respond differently to organic manures applied alone and in conjunction with reduced doses of chemical fertilizers under rainfed conditions and these research findings also suggest evaluating organic manures from plant and animal origins to obtain comparable wheat yield as that of chemical fertilizers. [ABSTRACT FROM AUTHOR]

This study was conducted to isolate and identify lactobacilli from larval and adult midgut of wild Aedes aegypti (Ae. aegypti) to find candidate bacteria for paratransgenic control. Characterization of the bacterial symbionts was done using Gram staining, motility test, catalase test, and biochemical tests, among others, and the morphological features were confirmed using a standard scheme that simplifies the identification of lactic acid bacteria. A total of 174 strains were isolated and identified, 135 strains from larval midgut and 39 strains from adult midgut (mean ± SE, 4.00 ± 0.72; P = 0.00). The isolated species were confirmed to be Lactobacillus fermentum, L. casei, L. acidophilus, L. viridescens, L. brevis and L. gasseri. It can be concluded that Ae. aegypti has the potential of harboring the cultivable bacterial symbionts. In conclusion, the isolated species were nominated for paratransgenic control, particularly L. fermentum, being found in large numbers from both larval and adulxt midgut. [ABSTRACT FROM AUTHOR]

Insecticide-based vector control approaches are facing challenges due to the development of resistance in vector mosquitoes. Therefore, a proper resistance surveillance program using baseline lethal concentrations is crucial for resistance management strategies. Currently, the World Health Organization's (WHO) diagnostic doses established for Aedes aegypti and Anopheles species are being used to study the resistance status of Aedes albopictus. In this study, we established the diagnostic doses for permethrin, deltamethrin, and malathion using a known susceptible reference strain. Five field-collected populations were screened against these doses, following the WHO protocol. This study established the diagnostic dose of malathion at 2.4%, permethrin at 0.95%, and deltamethrin at 0.28%, which differ from the WHO doses for Aedes aegypti and Anopheles spp. Among the insecticides tested on the 5 wild populations, only deltamethrin showed high effectiveness. Different susceptibility and resistance patterns were observed with permethrin, malathion, and dichloro-diphenyl-trichloroethane (DDT) at 4%. This study may assist the health authorities to improve future chemical-based vector control operations in dengue-endemic areas. [ABSTRACT FROM AUTHOR]

Dengue vector control still heavily relies on the use of chemical insecticides, and the widespread use of insecticides has led to resistance in mosquitoes. The diagnostic dose is a key part of resistance monitoring. The present study corroborates the discriminating lethal doses of temephos and malathion based on dose-response of known susceptible strain of Aedes albopictus following the World Health Organization (WHO) diagnostic test procedure. Late 3rd and early 4th instars were tested with a range of larvicides to determine the lethal concentrations (LC50 and LC99) values. A slightly higher diagnostic dose of 0.020 mg/liter as compared with the WHO-established value of 0.012 mg/liter was observed for temephos. Meanwhile, a malathion diagnostic dose of 0.200 mg/liter is also reported here since there are no such reported values by WHO. Doubling the LC99 values of susceptible strains, 3 of the 5 wild-collected populations showed resistance to temephos and 2 showed incipient resistance; all 5 populations showed incipient resistance to malathion. The revised and established lethal diagnostic dose findings from the current work are crucial to elaborate on the variation in susceptibility of Ae. albopictus in future resistance monitoring programs in Malaysia. [ABSTRACT FROM AUTHOR]

The life table developmental attributes of laboratory colonies of wild strains of Aedes albopictus and Aedes aegypti were analyzed and compared based on the age-stage, two-sex life table. Findings inclusive in this study are: adult preoviposition periods, total preoviposition period, mean intrinsic rate of increase ( r), mean finite rate of increase ( λ), net reproductive rates ( R0), and mean generation time ( T). The total preadult development time was 9.47 days for Ae. albopictus and 8.76 days for Ae. aegypti. The life expectancy was 19.01 days for Ae. albopictus and 19.94 days for Ae. aegypti. Mortality occurred mostly during the adult stage. The mean development time for each stage insignificantly correlated with temperature for Ae. albopictus ( r = −0.208, P > 0.05) and ( r = −0.312, P > 0.05) for Ae. aegypti. The population parameters suggest that Ae. albopictus and Ae. aegypti populations are r-strategists characterized by a high r, a large R0, and short T. This present study provides the first report to compare the life parameters of Ae. albopictus and Ae. aegypti strains from Penang island, Malaysia. [ABSTRACT FROM AUTHOR]

The present study was conducted to explore the fauna and biodiversity of family Carabidae (Coleoptera) from ten different localities of district Poonch, Pakistan during the year 2009-2010. Diversity, abundance, richness and evenness were calculated. A total of 288 specimens of family Carabidae (Coleoptera) were collected. Five species belonging to 3 sub-families (Licininae, Carabinae, Brachininae) in three genera were identified. Carabus caschmirensis was the most abundant species, followed by Chlaenius quadricolar, Pheropsophus sobrinus, Chlaenius laticollis and then Chlaenius hamifer. Diversity abundance richness and evenness were calculated. The highest abundance, richness and diversity of the family Carabidae was recorded from Rawalakot and the lowest diversity was calculated from Alisojal. The lowest abundance was recorded from Datot. The highest evenness of the family Carabidae was recorded from Rawalakot and lowest was recorded from Alisojal. [ABSTRACT FROM AUTHOR]

For ensuring food security and imparting sustainability to modern commercial-oriented and highly intensive temperate farming systems, organic wastes from poultry and dairy industries constitute biologically viable strategy to improve crops productivity under changing climate. A field trial was undertaken to appraise the impact of broiler litter (BL = 5 tons ha−1), farm yard slurry (FYS = 10 tons ha−1), and chemical fertilizers including di-ammonium phosphate (DAP = 60 kg ha−1) and single super phosphate (SSP = 60 kg ha−1) applied solely and in conjunction with each other, along with a control treatment (NM). The synergistic fertilization regime encompassing BL+DAP triggered the vegetative growth of soybean as indicated by taller plants having thicker stems and higher leaf area per plant compared to NM. In addition, this fertilization management system improved reproductive yield attributes including pods number and 100-seeds weight which maximized the seed yield, harvest index, seed oil content, and biological yield by 66%, 5%, 31%, and 23% respectively than NM. Moreover, this fertilizers combination was followed by SSP + BL, while BL performed better than FYS and DAP remained superior to SSP. Furthermore, the correlation analyses indicated moderately stronger direct association of seed yield with vegetative growth traits and highly stronger linear relationship with reproductive yield attributes. Thus, co-application of broiler litter (5 tons ha−1) with reduced doses of DAP (60 kg ha−1) might be recommended to temperate soybean growers having access to poultry wastes. [ABSTRACT FROM AUTHOR]

In traditional row and strip cowpea-sorghum intercropping systems, cowpea forage yield reduces significantly due to intense competition and dominance of sorghum in acquiring growth resources. This field study evaluated novel mixed strip intercropping systems of forage cowpea and sorghum having different number of crops rows arranged under different spatial arrangements. Cowpea was intercropped with sorghum in 8, 12 and 16 rows strips with row-row spacing of 30, 45 and 60 cm. In each strip, equal number of rows of cowpea and sorghum were maintained. Factorial arrangement of randomized complete block design with three replicates was used to execute the field trials during summer seasons of 2013 and 2014. Strips having 12 rows and 60 cm rowrow spacing positively affected all agronomic variables of cowpea which led to maximum forage yield (22.2 and 23.7 t ha-1 during 2013 and 2014 respectively) and dry matter biomass (6.63 and 6.94 t ha-1 during 2013 and 2014 respectively). In contrast, 8-rows strips having line spacing of 30 cm outperformed other intercropping systems by yielding the maximum herbage yield and dry matter biomass of sorghum. The intercropping system comprising of 12-rows strips with 60 cm row-row spacing remained superior in recording the maximum crude protein, fats and total ash along with the minimum fiber content of cowpea. In addition, this intercropping system under rest of spatial arrangements also remained unmatched, while 16-rows strips under all planting geometries remained inferior to other intercropping systems. Thus, cowpea intercropping with sorghum in 12-rows strips having 60 cm spacing offers biologically viable solution to improve biomass and forage quality of cowpea in intercropping with sorghum. [ABSTRACT FROM AUTHOR]

Imaging is increasingly used to detect and monitor bacterial infection. Both anatomic (X-rays, computed tomography, ultrasound, and MRI) and nuclear medicine ([ 111 In]-WBC SPECT, [ 18 F]FDG PET) techniques are used in clinical practice but lack specificity for the causative microorganisms themselves. To meet this challenge, many groups have developed imaging methods that target pathogen-specific metabolism, including PET tracers integrated into the bacterial cell wall. We have previously reported the d-amino acid derived PET radiotracers d-methyl-[ 11 C]-methionine, d-[3- 11 C]-alanine, and d-[3- 11 C]-alanine-d-alanine, which showed robust bacterial accumulation in vitro and in vivo . Given the clinical importance of radionuclide half-life, in the current study, we developed [ 18 F]3,3,3-trifluoro-d-alanine (d-[ 18 F]-CF 3 -ala), a fluorine-18 labeled tracer. We tested the hypothesis that d-[ 18 F]-CF 3 -ala would be incorporated into bacterial peptidoglycan given its structural similarity to d-alanine itself. NMR analysis showed that the fluorine-19 parent amino acid d-[ 19 F]-CF 3 -ala was stable in human and mouse serum. d-[ 19 F]-CF 3 -ala was also a poor substrate for d-amino acid oxidase, the enzyme largely responsible for mammalian d-amino acid metabolism and a likely contributor to background signals using d-amino acid derived PET tracers. In addition, d-[ 19 F]-CF 3 -ala showed robust incorporation into Escherichia coli peptidoglycan, as detected by HPLC/mass spectrometry. Based on these promising results, we developed a radiosynthesis of d-[ 18 F]-CF 3 -ala via displacement of a bromo-precursor with [ 18 F]fluoride followed by chiral stationary phase HPLC. Unexpectedly, the accumulation of d-[ 18 F]-CF 3 -ala by bacteria in vitro was highest for Gram-negative pathogens in particular E. coli . In a murine model of acute bacterial infection, d-[ 18 F]-CF 3 -ala could distinguish live from heat-killed E. coli , with low background signals. These results indicate the viability of [ 18 F]-modified d-amino acids for infection imaging and indicate that improved specificity for bacterial metabolism can improve tracer performance., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)