Vulnerable groups and protective habits associated with the number of symptoms caused by pesticide application in Kratie, Cambodia: a cross-sectional questionnaire study

Objective: The present study aimed to identify pesticide poisoning symptoms and related protective habits to effectively prevent pesticide poisoning among farmworkers in Kratie, Cambodia, where pesticide poisoning is an urgent public health problem. Materials and Methods: This cross-sectional study based on a questionnaire survey analyzing social demographics, number of symptoms, and protective behavior regarding pesticide application was conducted in Kratie Province from January 25 to 31, 2021. In total, 210 farmworkers completed the survey. The effects of social demographics and pesticide-protective behavioral scores on the number of symptoms were investigated using multivariable regression analysis. Results: The observed number of symptoms was 1.16 times higher among women (P=0.004), increased with the duration of work, and decreased with age. In addition, we identified five significant pesticide-protective behaviors: 1) preparing using gloves, 2) using protective equipment, 3) avoiding wiping sweat, 4) avoiding leaking, and 5) resting when feeling ill. Pesticide-protective behaviors tended to decrease with the duration of working years in the low-education group (B=-0.04, SE=0.01), whereas no association was observed in the high-education group (B=0.01, SE=0.01). Conclusion: Pesticide-protective behaviors significantly correlated with fewer symptoms. The female and aging groups required continuous special education or instructions for implementing pesticide-protective actions, especially the aforementioned five protective actions.

Molecular specific and cell selective cytotoxicity induced by a novel synthetic HLA-DR antibody mimic for lymphoma and leukemia

Like rituximab, monoclonal antibodies reactive with human leukocyte antigen have potent antilymphoma activity. However, size limits their vascular and tissue penetration. To mimic monoclonal antibody binding, nanomolecules have been synthesized, shown specific for the beta subunit of HLA-DR10, and selective for cells expressing this protein. Selective high affinity ligands (SHALs) containing the 3-(2-([3-chloro-5-trifluoromethyl)-2-pyridinyl]oxy)-anilino)-3-oxopropanionic acid (Ct) ligand residualized and had antilymphoma activity against expressing cells. Herein, we show the extraordinary potency in mice with human lymphoma xenografts of a tridentate SHAL containing this ligand. After titrating antilymphoma activity in cell culture, a randomized preclinical study of a tridentate SHAL containing the Ct ligand was conducted in mice with established and aggressive human lymphoma xenografts. Mice having HLA-DR10 expressing Raji B- or Jurkat's T-lymphoma xenografts were randomly assigned to receive either treatment with SHAL at a dose of 100 ng i.p. weekly for 3 consecutive weeks, or to be untreated. Primary end-points were cure, overall response rates and survival. Toxicity was also evaluated in these mice, and a USFDA general safety study was conducted in healthy Balb/c mice. In Raji cell culture, the threshold and IC50 concentrations for cytotoxic activity were 0.7 and 2.5 nmol (pm/ml media), respectively. When compared to treated Jurkat's xenografts or untreated xenografts, Raji xenografts treated with the SHAL showed an 85% reduction in hazard of death (P=0.014; 95% confidence interval 32-95% reduction). There was no evidence for toxicity even after i.p. doses 2000 times greater than the treatment dose associated with cure of a majority of the mice with Raji xenografts. When compared with control groups, treatment selectively improved response rates and survival in mice with HLA-DR10 expressing human lymphoma xenografts at doses not associated with adverse events and readily achievable in patients.