Leaf extracts of eight selected southern African medicinal plants modulate pro-inflammatory cytokine secretion in LPS-stimulated RAW 264.7 macrophages.

This study investigates the anti-inflammatory properties of extracts prepared from the leaves of eight southern African medicinal plants used traditionally to treat inflammation and pain. The inhibitory effect of aqueous and ethanol extracts on the release of pro-inflammatory cytokines was determined in lipopolysaccharide (LPS) stimulated and unstimulated RAW 264.7 murine macrophage cells. The levels of interleukin (IL)-1ß, IL-6, tumour necrosis factor-α (TNF-α), interferon-gamma (IFN-γ), monocyte chemoattractant protein 1 (MCP-1) and macrophage inflammatory protein (MIP)-2 release were determined using cytokine multiplex-bead assays. The ethanol extracts of Melianthus comosus Vahl (commonly known as honey flower), Tetradenia riparia (Hochst.) Codd (misty plume bush) and Warburgia salutaris (G. Bertol.) Chiov. (pepper-bark tree), demonstrated the most significant inhibitory activity, with over 50-fold inhibition of IL-1ß, IL-6 and TNF-α levels in LPS-stimulated RAW 264.7 macrophages. The aqueous extract of M. comosus also significantly inhibited the secretion of all the tested cytokines and chemokines. Phytochemical investigation of M. comosus ethanol leaf extract using ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry (UHPLC-HRMS) led to the detection of crassolide, deoxylimonoic acid D-ring-lactone, 2-hydroxynonanoic acid and 5-noniloxytryptamine. To the best of our knowledge, the cytokine inhibition properties of most of the medicinal plants screened in this study are reported for the first time. Our results support the use of southern African medicinal plants as anti-inflammatory remedies and provide an insight into the immunomodulatory mechanisms of action.

The Association Between Dating Violence and Student Absenteeism Among a Representative Sample of U.S. High School Students: Findings From the 2019 Youth Risk Behavior Survey Survey.

Student absenteeism affects students' engagement in school and academic and professional success. While research documents a significant association between school bullying/fighting and student absenteeism due to fear of being at school or getting to school, little research has examined the association of adolescent dating violence (ADV) victimization with this type of absenteeism. This study examined the relationship between physical and/or sexual ADV victimization in the past year (dichotomized as yes or no), and number of days of student absenteeism due to feeling unsafe at school or on the way to school in the past month (dichotomized as any vs. none). We analyzed cross-sectional data from the 2019 Youth Risk Behavior Survey (YRBS), a nationally representative survey of U.S. high school students (n = 9507). We conducted crude and multivariate regression models for the total sample and stratified by sex to assess our hypothesized association of ADV victimization and absenteeism; sex, grade, race/ethnicity, and sexual identity were included as covariates in adjusted models. Findings demonstrate that students reporting past year ADV victimization had 3.69 times the odds of student absenteeism due to feeling unsafe, when compared to students who did not report ADV victimization (95% CI: 3.06-4.45, p < 0.001). Sex-stratified models reveal that this effect is significantly stronger for males than for females, as indicated by non-overlapping confidence intervals (male AOR: 5.67, 95% CI: 4.18-7.68; female AOR: 2.95, 95% CI: 2.32-3.74). The multivariate models also show that Black and Latinx compared with White students, and lesbian/gay/bisexual/unsure compared with heterosexual students, had higher odds of student absenteeism due to feeling unsafe. Findings indicate the need to address ADV victimization and student absenteeism with integrated and gender-tailored responses, and with consideration of greater vulnerabilities for queer students and students of color.

COVID-19 burden, author affiliation and women's well-being: A bibliometric analysis of COVID-19 related publications including focus on low- and middle-income countries.

Background: Published literature documents tremendous gender inequities in the social, economic and health effects of the COVID-19 pandemic, but less evidence has come from low- and middle-income countries (LMICs) and even less from LMIC-based authors. We examine whether a) COVID-19 burden and b) LMIC-based authorship were associated with academic publications related to COVID-19 and women's well-being in LMICs. Methods: We reviewed academic articles on COVID-19 and women's well-being in LMICs published between February 2020 and May 2021 (n=1076 articles), using six electronic databases (PubMed, Web of Science, PsycInfo, EconLit, RePeC, NBER). Multilevel, mixed effects linear regressions assessed the relationships between each of our independent variables - a) COVID-19 burden (cases/100 population, deaths/100 population, deaths/cases) and b) author's country of primary affiliation, with publications related to COVID-19 and women's well-being, both overall and stratified by country income group. Findings: Eight-eight percent of articles had lead and/or senior authors affiliated with in-country institutions. Linear mixed effect models indicate that COVID-19 cases and case fatality ratios in a country were significantly and positively associated with the number of publications related to COVID-19 and women's well-being, though these relationships were significant only in upper-middle income group countries in stratified analyses. LMIC lead and senior authorship were also significantly and positively associated with our outcome, after adjusting for COVID-19 burden. Interpretation: While the majority of COVID-19 research examining women's well-being in LMICs in the first year and a half of the pandemic included country-affiliated author leadership, there were important gaps in representation. Findings highlight the importance of LMIC-based scholars to build local and gendered research in crises. Funding: Bill and Melinda Gates Foundation (INV-018007).

A network psychometric validation of the Children Oral Health-Related Quality of Life (COHQoL) questionnaire among Aboriginal and/or Torres Strait Islander children.

In Australia, research evidence has shown that Aboriginal and/or Torres Strait Islander children experience a higher burden of oral health diseases compared to other non-Indigenous children. The impact of oral health diseases on children's functional and psychosocial outcomes led to the development of several instruments to evaluate child oral health-related quality of life (COHQoL), such as the Parental-Caregiver Perception Questionnaire (P-CPQ) and the Family Impact Scale (FIS). However, the psychometric properties of these instruments have been evaluated only in Western cultures and have not been investigated for Aboriginal children in Australia. The current study aimed to examine the psychometric properties of the short-forms P-CPQ and FIS for Aboriginal and/or Torres Strait Islander children aged 2-3 years. Data were collected from the South Australian Aboriginal Birth Cohort (SAABC), including 270 Aboriginal children aged 2-3 years. Network psychometric models were used to investigate dimensionality, item redundancy, structural consistency and item stability, model fit, internal consistency reliability and criterion validity. We propose an instrument named Aboriginal Children's Oral Health-Related Quality of Life Questionnaire (A-COHQoL). Our findings indicated that, after the exclusion of four problematic items, the A-COHQoL showed a three-dimensional structure ("Parent/Family Activities", "COHQoL" and "Family Conflict") with good model fit and reliability. The A-COHQoL is a psychometrically robust and sensitive instrument that is readily available for Aboriginal and/or Torres Strait Islander children aged 2-3 years in Australia and can be adapted in the future for Indigenous child groups in other countries.

Traumatic dental injuries presenting to a paediatric emergency department in a tertiary children's hospital, Adelaide, Australia.

BACKGROUND/AIM: There is a scarcity of data regarding paediatric traumatic dental injuries (TDI) in tertiary teaching hospitals. Therefore, the aim of this study was to review the TDI presenting to the Women's and Children's Hospital in Adelaide (Australia) on an emergency basis and to identify the characteristics of the presenting patient cohort, their accident, injuries and management. METHODS: Medical health records of 337 paediatric patients attending the Paediatric Emergency Department (PED) for the management of TDI over 18 months were prospectively reviewed. RESULTS: TDI were more frequent in children under 5 years of age (56.1%) with a predominance of injuries sustained by males (63.8%). The accident characteristics included weekend occurrence (35.6%), the most common aetiology was falls (64.4%) and many incidents occurred at home (48.5%). Overall, 654 teeth were injured with the majority affecting deciduous teeth (58.4%) and the maxillary central incisors (69.9%). The most frequent injury was lateral luxation (27.5%). The majority of patients were referred to the Paediatric Dentistry Department (60.8%). However, almost half of presenting patients did not require further management locally and were subsequently discharged to their dental practitioners (39.2%). Most patients receiving treatment were managed under general anaesthetic (36.9%), and there was often a delay of 3-12 hours before treatment commenced (49.1%). Similarly, more severe injuries in the permanent dentition (avulsion, extrusion, root fracture, intrusion, alveolar fracture) were more frequently managed between 3 and 12 hours following the accident. CONCLUSION: The patient, accident, injury and management characteristics are comparable to what has previously been reported in other studies in paediatric populations. Injuries affecting the permanent dentition are more likely to be managed within 3 and 12 hours in an outpatient setting, whereas injuries affecting the deciduous dentition had a delay in management between 12 and 24 hours under general anaesthetic.

Identification of a New α-Synuclein Aggregation Inhibitor via Mass Spectrometry Based Screening.

The aggregation of disordered α-synuclein protein is pathogenically connected with Parkinson's disease. Therefore, discovering molecules that can inhibit the misfolding and aggregation of α-synuclein is an active research area in PD drug development. A key property of such required therapeutic agents is specific binding to the target protein. Mass spectrometry allows rapid detection of direct interactions between molecules and proteins and is an ideal technique for discovering specific α-synuclein binders. Here, by setting up an automated mass spectrometry-based screening system, we were able to screen over 2500 compounds and identify a new α-synuclein inhibitor, 3-[(3-methoxyphenyl)carbamoyl]-7-[( E)-2-phenylethenyl]-4,7-dihydropyrazolo [1,5- a]pyrimidine-5-carboxylic acid (compound 2). This compound not only significantly inhibits the misfolding and aggregation of α-synuclein and protects neuroblastoma cells from α-synuclein toxicity, but also has a more specific binding site compared with positive controls. Our work for the first time reports the inhibition of compound 2 on α-synuclein aggregation and also consolidates the capability of mass spectrometry to discover α-synuclein aggregation inhibitors.

Insight into Health Care Outcomes for Persons Living with Heart Failure Using Health Data Analytics.

The Integrated Funding Model (IFM) is designed to measure the impact of a bundled model of health care for patients with Congestive Heart Failure (CHF) for a period of 60 days post discharge. CHF is a primary reason for patient admissions. The goal of this study is to gain insight into the effectiveness of the IFM pathway intervention on health care outcomes for persons living with CHF, using Health data Analytics.

Supportive Cardiology: Moving Palliative Care Upstream for Patients Living with Advanced Heart Failure.

Heart failure (HF) affects ∼600,000 Canadians and is a chronic, life-limiting illness marked by exacerbations of distressing symptoms requiring acute medical management, typically sought in Canada's emergency departments. HF often has an unpredictable illness trajectory and is a chronic terminal illness with a poor prognosis. Patients living with advanced HF have difficulty in accessing palliative care (PC) supports, which can result in unnecessary suffering as their HF progresses and they near end of life (EOL). This is, in part, due to a lack of research, helping clinicians to identify patients who are approaching EOL. In addition, the unpredictable nature of illness progression often precludes access to most EOL resources in our current prognosis-dependent healthcare system. PC teams focus on optimizing quality of life through symptom management and ensure that care plans are congruent with patient and family preferences. A PC team was embedded into our institution's existing HF team. Findings show that integration of an embedded model of PC delivery for patients living with advanced HF led to overwhelming positive patient and family feedback while providing timely advance care planning discussions that may be associated with beneficial patient, family, and system outcomes. These outcomes can be used to inform public policy and speak to a cost-effective patient and family-centered approach for providing care to individuals and families living with advanced HF.

Epicocconone-Hemicyanine Hybrids: Near Infrared Fluorophores for Protein Staining and Cell Imaging.

The development of new near infrared (NIR) dyes is crucial for diverse applications and especially bioimaging, as they absorb and emit light in the "therapeutic window" (650-950 nm). We report here a new family of NIR fluorophores that has been obtained by hybridising hemicyanines with epicocconone. Emission wavelengths of these hybrid dyes is in the range 715-795 nm and is combined with large Stokes' shifts (75-95 nm). The absorption and emission wavelength can be modulated according to the hemicyanine moiety and adding sulfonic acid moieties enhances water solubility. We demonstrate their application in the sensitive detection of proteins in gel electrophoresis and the staining of specific cellular organelles in confocal microscopy. These results are particularly encouraging and bring forward a new fluorescent skeleton for chemical biology.

UHPLC/ESI-MS/MS Determination of 187 Pesticides in Wine.

This paper presents an ultra HPLC/electrospray ionization-tandem MS method to determine pesticides in wine. We adopted the quick, easy, cheap, effective, rugged, and safe (QuEChERs) method for extraction and used core-shell column to achieve ultra-HPLC to develop and validate a simple and fast method to analyze 187 pesticide residues in red and white wine samples. Pesticide residues were extracted from wine samples using QuEChERS. Ultra HPLC/electrospray ionization-tandem MS quantification was achieved using matrix-matched standard calibration curves with isotopically labeled standards or a chemical analogue as internal standards with an analytical range from 5.0 to 500.0 µg/L. The method performance characteristics that included overall recovery, intermediate precision, and measurement uncertainty were evaluated according to a nested experimental design. Generally, 98.4% (in red wine) and 96.8% (in white wine) of the pesticides had recoveries between 71 and 120%; 98.9% (in red wine) and 99.5% (in white wine) of the pesticides had the intermediate precision ≤20%; and 99.5% (in red wine) and 98.4% (in white wine) of the pesticides had measurement uncertainty ≤50%.

Antimicrobial and antioxidant activity and chemical characterisation of Erythrina stricta Roxb. (Fabaceae).

ETHNOPHARMACOLOGICAL RELEVANCE: The bark of Erythrina stricta Roxb. (Fabaceae) has been used in Indian indigenous systems as a remedy for rheumatism, stomach-ache, asthma, dysentery, contact dermatitis, eczema and skin infections. However, there have been limited phytochemical or biological studies on the bark of E. stricta and there are no studies that align with its traditional medicinal uses. AIM OF THE STUDY: The aim of this study was to assess the antimicrobial and antioxidant activity of the stem bark of E. stricta to support its topical use in the treatment of contact dermatitis, eczema and skin infections and to isolate and identify any bioactive compounds. MATERIALS AND METHODS: MTT microdilution and disc diffusion assays were used to determine the antimicrobial activities of n-hexane, dichloromethane, ethyl acetate, methanol and water extracts of the bark of E. stricta. Column and preparative thin layer chromatography were used for the purification of the dichloromethane extract. The structures of the compounds isolated were elucidated by extensive 1D and 2D NMR spectroscopic techniques and comparison with published data. The antioxidant activities of the extracts were determined by DPPH free radical scavenging and FRAP assays and the antioxidant activity of the pure compounds by dot-blot and DPPH staining methods. RESULTS: The dichloromethane, ethyl acetate, and n-hexane extracts showed the most significant activity with MIC values of 7.8µg/mL, 125µg/mL, and 125µg/mL against a sensitive strain of Staphylococcus aureus. The dichloromethane and ethyl acetate extracts also showed significant activity against Candida albicans with MIC values of 125µg/mL and 1mg/mL respectively. GC-MS analysis of the n-hexane extract showed the presence of the antibacterial and antifungal compounds ß-caryophyllene, caryophyllene oxide, α-selinene, ß-selinene, selin-11-en-4-α-ol, α-copaene and δ-cadenine. Phytochemical studies of the dichloromethane extract led to the isolation of the novel compound erynone (1), together with six known compounds; wighteone (2), alpinum isoflavone (3), luteone (4), obovatin (5), erythrinassinate B (6) and isovanillin (7). Luteone (4) exhibited the most significant antibacterial activity with minimum inhibitory quantity (MIQ) values of 1.88µg, 1.88µg and 3.75µg, respectively, against sensitive (MSSA) and resistant strains (MRSA and MDRSA) of S. aureus using a TLC bioautography assay. Erynone (1) exhibited the greatest DPPH free radical scavenging activity. CONCLUSIONS: Seven compounds, including a new chromanone, were isolated from the antimicrobial dichloromethane extract of the stem bark of E. stricta. Six of the seven compounds showed antibacterial and/or antioxidant activities. These findings provide support for the customary (traditional and contemporary) use of E. stricta bark for the treatment of skin and wound infections.

Determination of pesticide residue transfer rates (percent) from dried tea leaves to brewed tea.

This paper presents a study on pesticide residue transfer rates (%) from dried tea leaves to brewed tea. In the study, a brewing procedure simulated the preparation of a hot tea drink as in routine. After brewing, pesticide residues were extracted from brewed tea using a method known as QuEChERS (quick, easy, cheap, effective, rugged, and safe). An UHPLC/ESI-MS/MS method was developed and validated to identify and quantify up to 172 pesticides in both tea leaves and brewed tea samples. Quantification was achieved using matrix-matched standard calibration curves with isotopically labeled standards or a chemical analogue as internal standards, and the calibration curves consisted of six points (0.4, 2.0, 8.0, 16.0, 24.0, and 40.0 µg/L equivalent in sample). The method was validated at four concentration levels (4.0, 12, 20.0, and 32.0 µg/L equivalent in sample) using five different brewed tea matrices on two separate days per matrix. Method performance parameters included overall recovery, intermediate precision, and measurement uncertainty, which were evaluated according to a nested experimental design. Approximately, 95% of the pesticides studied had recoveries between 81 and 110%, intermediate precision ≤20%, and measurement uncertainty ≤40%. From a pilot study of 44 incurred tea samples, pesticide residues were examined for their ability to transfer from dried tea leaves to brewed tea. Each sample, both tea leaves and brewed tea, was analyzed in duplicate. Pesticides were found to have different transfer rates (%). For example, imidacloprid, methomyl, and carbendazim had transfer rates of 84.9, 83.4, and 92.4%, respectively.

Ultra-high performance liquid chromatography/ electrospray ionization-tandem mass spectrometry determination of 151 pesticides in soybeans and pulses.

This paper presents the application of ultra-high performance LC (UHPLC) and MS for the determination of 151 pesticides in soybeans and pulses. A core-shell particle (2.6 micro m particle size) column and a fully porous sub-2 microm (1.7 microm particle size) column showed comparable performance in chromatographic resolution and separation, increasing selectivity, and reducing analysis time. UHPLC was coupled with either a triple quadrupole mass analyzer (MS/MS) or a quadrupole Orbitrap (namely Orbital trap) mass spectrometer (Q-Orbitrap MS), which possesses fast data acquisition capability. Both configurations yielded analytical run times of < or =14 min. Soybean and pulse samples were analyzed and quantitated for pesticide residues using the QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) procedure, UHPLC/electrospray ionization (ESI)-MS/MS, and matrix-matched standard calibration curves (in an analytical range of 5-500 microg/kg) with isotopically-labeled standards or a chemical analog as internal standards. The method performance parameters that included overall recovery, intermediate precision, and measurement uncertainty were evaluated according to a nested design experiment. Approximately 89% of the pesticides studied had recoveries between 81 and 110%; 95%, had intermediate precision < or =20%; and 93% showed measurement uncertainty < or =40%. From a pilot study of 100 samples, eight tested positive by UHPLCIESI-MS/MS for carbendazim, methomyl, or imidacloprid. These pesticides were further confirmed using UHPLC/ESI-Q-Orbitrap MS based on accurate mass measurement with mass error < or =5 ppm.

Satisfaction with student pharmacists administering vaccinations in the University of Alberta annual influenza campaign.

OBJECTIVE: To evaluate University of Alberta staff and students' acceptance of and satisfaction with receiving influenza vaccinations from student pharmacists during the university's annual influenza campaign. MATERIAL AND METHODS: A patient survey was created to collect patient demographics, influenza history and feedback on the services provided by pharmacy students and to measure willingness to receive vaccinations from a pharmacist in a community pharmacy. The 13-question survey was distributed to patients who received an influenza vaccination from a student pharmacist during the influenza campaign. KEY FINDINGS: A total of 1555 staff and students completed the satisfaction survey. Almost all (n = 1533, 99%) survey participants were satisfied or very satisfied with the service provided by student pharmacists. A total of 1437 (92%) participants agreed or strongly agreed that based on this experience, they would be willing to receive vaccinations from a pharmacist in a community pharmacy and 1526 (98%) participants rated their overall experience at the flu clinic as very good or excellent. CONCLUSIONS: Positive responses to the survey suggest that University of Alberta staff and students are satisfied with the service provided by student pharmacists. Their willingness to receive vaccines from a pharmacist in a community pharmacy highlighted public acceptance of the expanding role of pharmacists as immunizers.

Expression of ESBL-like activity in infrequently encountered members of the family Enterobacteriaceae.

A collection of 94 unusual members of the Enterobacteriaceae were screened for the presence of extended spectrum ß-lactamases (ESBLs) using the MicroScan ESßL plus dried confirmation panel. Presumptively positive strains were then confirmed for the presence of an ESBL by double disk diffusion, E-test strips (AB Biodisk, Solna, Sweden) and PCR for SHV, TEM, and CTX-M2 genes. Of the 18 strains initially positive on the ESßL panel only three strains (Leminorella grimontii, Klebsiella ozaenae, and Kluyvera ascorbata) were positive by confirmation methods. These results suggest laboratories should be cautious regarding the methodology employed in screening for the presence of ESBLs in enteric bacteria. However, it should be noted that of the 94 strains, 29 were found to be resistant to two or more of the antibiotics present in the MicroScan ESßL plus panel indicating that there are potential treatment issues with these organisms despite their lack of ESBLs.

Application of a tandem mass spectrometer and core-shell particle column for the determination of 151 pesticides in grains.

A comparison of ultrahigh performance liquid chromatography (UHPLC) with a 2.6 µm core-shell particle column (Kinetex C(18)) and conventional liquid chromatography (LC) with a 3 µm porous particle column (Atlantis dC(18)), coupled with electrospray ionization tandem mass spectrometry (ESI-MS/MS), for the determination of 151 pesticides in grains is presented in this study. Pesticides were extracted from grain samples using a procedure known as QuEChERS (quick, easy, cheap, effective, rugged, and safe). Quantification, with an analytical range from 5 to 500 µg/kg, was achieved using matrix-matched standard calibration curves with isotopically labeled standards or a chemical analogue as internal standards. The method performance parameters that included overall recovery, intermediate precision, and measurement uncertainty were evaluated using a designed experiment, that is, the nested design. The UHPLC (Kinetex C(18)) was superior to conventional LC (Atlantis dC(18)) as it yielded a shorter analytical run time, increased method sensitivity, and improved method performance. For UHPLC/ESI-MS/MS (Kinetex C(18)), 90% of the pesticides studied had recoveries between 81 and 110%, 88% of the pesticides had intermediate precision ≤20%, and 84% of the pesticides showed measurement uncertainty ≤40%. As compared to UHPLC/ESI-MS/MS (Kinetex dC(18)), the LC/ESI-MS/MS (Atlantis dC(18)) showed a relatively lower sensitivity, less repeatability, and larger measurement uncertainty. UHPLC/ESI-MS/MS with 2.6 µm core-shell particle column and scheduled MRM proved to be a good choice for quantification or determination of pesticides in grains.

A one-pot synthesis and biological activity of ageladine A and analogues.

A one-pot synthesis of ageladine A and analogues is reported. The key Pictet-Spengler reaction between 2-aminohistamine and aryl aldehydes has been successfully utilized for the synthesis of the natural product and 14 analogues. These compounds were screened for their matrix metalloprotease (MMP) and kinase inhibition to develop the first structure-activity relationship of ageladine A analogues. One compound, which showed significant kinase activity but little MMP inhibitory activity, was found to be highly active in an antiangiogenic screen, suggesting that the angiogenic activity of ageladine A is not associated with MMP inhibition but rather kinase inhibitory activity. Cytotoxicity was excluded as a mode of action by the assay of ageladine A and an analogue against 60 human cell lines.

Evaluation of commercial antisera for Salmonella serotyping.

We compared a set of commercial Salmonella somatic and flagellar serotyping antisera to in-house-prepared antisera from the Microbial Diseases Laboratory, California Department of Public Health, using 327 Salmonella enterica strains belonging to subgroups I, II, IIIa, IIIb, and IV. The sensitivities of Denka Seiken (Tokyo, Japan) somatic and flagellar antisera (using a tube agglutination assay) were 94.0% and 99.2%, respectively, and the specificity was 100% for both sets of sera. Polyvalent O and O1 antiserum sensitivity and specificity were >90%, with the exception of polyvalent O1 antiserum, for which sensitivity was 88.9%. When Denka Seiken flagellar antisera were used in a slide agglutination assay, the sensitivity and accuracy dropped to 88.9% and the specificity fell to 91%. Overall, Denka Seiken commercial antisera performed very well and, together with the comprehensive range of factors available, offer laboratories quality reagents suitable for serotyping strains of salmonellae.

Determination of pesticides in soy-based infant formula using liquid chromatography with electrospray ionization tandem mass spectrometry.

A sensitive method using liquid chromatography with electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) was developed and validated to quantify and confirm 13 pesticides, including aldicarb sulfoxide, aldicarb sulfone, oxamyl, methomyl, formetanate, 3-hydroxycarbofuran, carbendazim, thiabendazole, aldicarb, propoxur, carbofuran, carbaryl, and methiocarb, in soy-based infant formula. Data acquisition under MS/MS was achieved by applying multiple reaction monitoring of 2 fragment ion transitions to provide a high degree of sensitivity and selectivity for both quantitation and confirmation. Different approaches to constructing calibration curves were compared and discussed to address issues of the extraction efficiency or recovery, and matrix effects. Matrix-matched standard calibration curves with the use of isoprocarb as an internal standard were finally used to achieve the best accuracy of the method. Under most circumstances, recoveries of 13 pesticides, spiked at 5.0, 25.0, and 45.0 microg/kg, were close to 100%. The method detection limits (signal-to-noise ratio > or =3:1; microg/kg) of 13 pesticides were 0.2 for thiabendazole and methiocarb, 0.6 for aldicarb, and 0.1 for the others.