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Citrus spp. trees are not fully dormant during the winter months in the northern hemisphere; therefore, they are susceptible to sporadic freeze events of various magnitudes that could decline tree productivity or be lethal. In Feb 2021, winter storm Uri produced freezing air temperatures for nearly 72 hours, which created several degrees of injuries to citrus orchards in southern Texas. Producers in the area implemented combinations of multiple horticultural practices aimed at remediating injuries from the cold spell to stimulate root and tree recovery. However, there is a gap in our understanding of how practices such as compost application (CA) combined with varying rates of nitrogen (N) might facilitate tree recovery. Therefore, we conducted a 2-year field experiment using two CAs as soil amendments in combination with three N rates (112, 168, and 224 kg·ha21 N) to evaluate fruit yield and internal quality, root growth, and recovery of 'Rio Red' grapefruits (Citrus ×paradisi Macf.) and 'Marrs' sweet oranges (Citrus sinensis). The yields of both crops exhibited modest improvement with CA in 2022; however, it was nonsignificant. Moreover, CA elicited more beneficial effects than N rates alone when rehabilitating trees and improving fruit internal quality after freezing events. Grapefruit brix was 4% higher in fruits harvested from trees treated with compost, and grapefruit roots exhibited a twofold dry weight increment with CA. Sweet oranges from trees in the CA treatment had 22% lower acidity compared with that of untreated trees. Overall, our results indicate that citrus producers in southern Texas and other subtropical citrus-producing regions might facilitate the rehabilitation of tree injuries attributed to mild to moderate freeze events with moderate financial gains with the timely application of compost, which enhanced tree fitness and ameliorated fruit productivity declines during subsequent harvests. [ABSTRACT FROM AUTHOR]

The antibiotic lincomycin is commonly found in treated municipal waste water and in waste from swine and poultry production. Environmental disposal of these wastes has the potential to introduce a significant mass of lincomycin into the ecosystem. In the present study, a series of sorption and desorption experiments were conducted to determine the potential mobility of lincomycin in soils from arid environments. Sorption and desorption isotherms were obtained for lincomycin using three different soils. Isotherms were fit to the Freundlich equation. Adsorption of lincomycin was found to have a Kf of 11.98 for a biosolid-treated soil (1.58% OC) and a Kf of 210.15 for a similar unamended soil (1.42% OC). It was also found that for a low-organic-content soil the Kf was 5.09. The differences in adsorption can be related to the soil pH and the pKa of lincomycin (7.5-7.8). When the soil solution pH is below the pKa, the cationic species of lincomycin dominates, resulting in increased water solubility. Interaction with the cation exchange complex is minimal due to a high solution cation concentration (Ca2+ and Na+). Desorption isotherms also indicate that when the solution pH is lower than the pKa, retention of lincomycin is reduced. Our results indicate that the mobility of lincomycin in these arid region soils is dependent on soil pH. [ABSTRACT FROM AUTHOR]

Background: Pennyroyal is a widely available herb that has long been used as an abortifacient despite its potentially lethal hepatotoxic effects. However, quantitative data for pennyroyal constituents and their metabolites in humans have not been previously reported.Objectives: To quantify pennyroyal metabolites in human overdose, to correlate these findings with clinical variables, and to place these findings in the context of previously reported cases of pennyroyal toxicity.Design: Clinical case series of pennyroyal ingestions; quantification of pennyroyal metabolites by gas chromatography and mass spectrometry; qualitative detection of protein-bound adducts of the metabolites of pennyroyal constituents in human liver by Western blot assay; and review of the literature based on a search of MEDLINE, Index Medicus, and the reference citations of all available publications.Results: We report four cases of pennyroyal ingestion. One patient died, one received N-acetylcysteine, and two ingested minimally toxic amounts of pennyroyal and were not treated with N-acetylcysteine. In the fatal case, postmortem examination of a serum sample, which had been obtained 72 hours after the acute ingestion, identified 18 ng of pulegone per mL and 1 ng of menthofuran per mL. In a serum sample from the patient treated with N-acetylcysteine, which had been obtained 10 hours after ingestion, the menthofuran level was 40 ng/mL. Review of 18 previous case reports of pennyroyal ingestion documented moderate to severe toxicity in patients who had been exposed to at least 10 mL of pennyroyal oil.Conclusion: Pennyroyal continues to be an herbal toxin of public health importance. Data on human metabolites may provide new insights into the toxic mechanisms and treatment of pennyroyal poisoning, including the potential role of N-acetylcysteine. Better understanding of the toxicity of pennyroyal may also lead to stricter control of and more restricted access to the herb. [ABSTRACT FROM AUTHOR]

Eighty-one patients with farmer's lung were screened for evidence of coeliac disease by assessing their clinical features, haemoglobin indices, serum vitamin B and folic acid levels. HLA typing was carried out and the frequency of antireticulin and other auto-antibodies was determined. Two out of 21 patients selected for jejunal biopsy had subtotal villous atrophy, a further 6 had partial villous atrophy and 8 out of 21 had increased lamina propria cellularity. The group as a whole had an increased number of intra-epithelial lymphocytes in the jejunal musosa. Sera of 7 out of 81 patients contained antireticulin antibody compared with 2 of 81 control subjects, a difference without significance. Other autoantibodies were not more frequent in the patient than in the control group and were of normal incidence. HLA antigens were also similar in both groups. [ABSTRACT FROM PUBLISHER]

Dissolved organic matter (DOM) has been shown to form a stable complex with Napropamide [2(alpha-naphthoxy)-NN-diethyl propionamide] and to facilitate its transport through soil columns. Liquid-liquid extraction of organics is a common method to transfer napropamide from water into an organic phase for gas chromatography analysis. A study wasconducted to determine the effect of Aldrich humic acid, soil-derived dissolved organic matter, electrical conductivity, and hydrogen ionactivity on the ability of hexane to extract napropamide from solutions and from soil extracts. The electrical conductivity of Aldrich humic acid solutions (0.0, 48, and 100 mg c L-1) were adjusted to 0.01, 0.97, and 1.69 dS m-1 by adding NaCl and CaCl2, and pH (8.2, 7.4, and 5.6) was adjusted using HCI and NaOH. Electrical conductivity had no effect on extraction efficiency. In the absence of DOM pH had no effect on extraction efficiency. Extraction efficiency decreased with increasing DOM concentration. Maximumreduction in extraction efficiency occurred in the presence of DOM when solution pH was near neutrality. A maximum extraction efficiency of 100% was observed in the absence of DOM and a minimum of 68% when napropamide was added to DOM solutions at pH 8.2 and then lowered topH 5.6. Management practices such as liming and allowing napropamideto dry on the soil may increase environmental transport. Also quantification of napropamide in environmental samples can be affected by DOM. [ABSTRACT FROM AUTHOR]

Equilibrium dialysis is commonly used to measure the complex formed between dissolved organic matter (DOM) and pesticides such as napropamide [2(alpha-naphthoxy)-NA-diethyl propionamide]. Currently the dialysis method most often used employs dialysis tubing that is clamped on both ends. Limitations of the dialysis tubing method includedifficulty in sample addition to the dialysis tubing, dilutioneffects, and the need for large sample volumes. A new dialysis chamber constructed of Teflon and using flat dialysis membranes is described and characterized using napropamide as a model compound. Using a dialysis membrane with a molecular weight cut off of 500 Daltons the system reached equilibrium across the membrane within 120 h. Significant sorption of napropamide to the membrane was observed. Napropamidesorption was linear, reversible, and dependant on the membrane used.Sample addition and removal from the chamber is possible without destroying the integrity of the membrane. The dialysis chamber allowed for fast and easy quantitative addition and removal of sample for dialysis without wasting sample. The small chamber made possible dialysisof very small samples (as little as 1.5 mL) while maintaining a large surface area for diffusion. The chamber also provided dialysis witha maximum dilution factor of two since the volume of dialysate needed is equal to the volume of sample introduced. [ABSTRACT FROM AUTHOR]

Organic matter amendments to soil are usually thought to improve soil quality. Increased soil organic matter can lead to increased concentrations of dissolved organic matter (DOM). Complexation of DOM with pesticides can lead to increased aqueous phase concentration and therefore enhanced movement through the soil profile. Dissolved organic matter has been shown to form a stable complex with napropamide [2(a-naphthoxy)-N,1V-diethyl propionamidel and facilitate its transport through soil columns. Equilibrium dialysis is a common method to determine napropamide DOM complexation. Napropamide was applied to a silt loam soil with (SS) and without (NoSS) sewage sludge application. Solutions from batch equilibrium experiments were analyzed using equilibrium dialysis with various molecular weight cutoffs to determine napropamide DOM complexation. A maximum of 16% of solution phase napropamide was found to be associated with a DOM complex having a molecular weight >500 Daltons. The maximum complex size had a molecular weight <25 000 Daltons. More napropamide was complexed from the SS soil treatments than from the NoSS soil treatments. The presence of a drying event following napropamide application also was found to increase the amount of napropamide complexed in both the SS and NoSS soils. Resultsshow that the amount and molecular weight of napropamideDOM complexes is affected by organic matter type and application method. [ABSTRACT FROM AUTHOR]

Patients with an equivocal signal averaged electrocardiogram (SAECG) had less heart disease and better prognosis than patients with overtly abnormal SAECGs. An equivocal SAECG should not prompt further invasive diagnostic testing for ventricular tachycardia unless other clinical risk factors are present. [ABSTRACT FROM AUTHOR]