Bioavailability of non-aromatic brominated flame retardants in rats from dust and oil vehicles

Hexabromocyclododecane (HBCD) is a brominated flame retardant (BFR) labeled by the Stockholm Convention as a persistent organic pollutant (POP) and exists primarily as three stereoisomers, i.e. α-, β-, and γ. One of the major routes of human exposure to HBCD is dust found in homes, offices, and cars and dust may be the most important route of HBCD exposure in young children. A study was conducted to determine the oral bioavailability of HBCD from household dust in rats over a 21-d feeding period relative to HBCD bioavailability from a corn oil matrix. Twenty-four hours after the last exposure, rats were sacrificed, and various tissues were collected. HBCD diastereomers were detected in adipose, blood, and liver of both dose groups, suggesting HBCD is bioavailable from both oil and dust. β-HBCD concentrations were below the limit of detection in all tissues, but α-HBCD was detected in the brain of oil-dose rats and in adipose and liver of both dose groups. γ-HBCD was the dominant diastereomer in adipose, blood, and liver samples regardless of dosing matrix. Except for γ-HBCD in muscle of the oil-dosed group, muscle did not contain measurable HBCDs. Adipose tissue accumulated HBCD to a greater extent than muscle or liver, having bioaccumulation factors greater than 1.

Rapid quantification of cannabinoids in beef tissues and bodily fluids using direct-delivery electrospray ionization mass spectrometry

Hempseed cake is a byproduct of hempseed oil extraction and is potentially a useful source of protein and fiber for use in ruminant diets. However, data are lacking on the appearance and/or clearance of cannabinoids in tissues of animals fed hempseed cake. To this end, a rapid method for quantifying cannabinol (CBN), cannabidiol (CBD), cannabinolic acid (CBNA), cannabidiolic acid (CBDA), cannabigerolic acid (CBGA), cannabichromenic acid (CBCA), cannabidivarin (CBDV), cannabidivarinic acid (CBDVA), tetrahydrocannabinol (THC) and tetrahydrocannabinolic acid (THCA) in cattle tissues, plasma, and urine was developed using rapid screen electrospray ionization mass spectrometry (RS-ESI-MS). Regression coefficients of matrix-matched standard curves ranged from 0.9946 to >0.9999 and analyte recoveries averaged from 90.2 ± 15.5 to 108.7 ± 18.7% across all compounds. Limits of detection and quantification ranged from 0.05 to 2.79 ng · mL^-1 and 0.17 to 9.30 ng · mL^-1, respectively, while the inter-day relative standard deviation ranged from 5.1 to 15.1%. Rapid screening electrospray ionization mass spectrometry (RS-ESI-MS) returned no false positives for any cannabinoid in plasma, urine, and tissue (liver, skeletal muscle) samples from 6 non-dosed control animals (n = 90 samples; of which 72 samples were plasma or urine and 18 samples were tissues). Across-animal cannabinoid concentrations measured in 32 plasma samples of cattle dosed with ground hemp were quantified by RS-ESI-MS; analytical results correlated well (r² = 0.963) with independent LC-MS/MS analysis of the same samples.

Comparison of Serum Uric Acid Levels in Patients with Stable Chronic Obstructive Pulmonary Disease and Patients with Acute Exacerbation

Purine breakdown produces uric acid (UA) as a by-product. Serum UA levels have been reported to be higher in hypoxic people, including Chronic Obstructive Pulmonary Disease (COPD) patients. Serum UA has been suggested as a marker for impaired oxidative metabolism, and it is also thought to play a role in the prognosis and evaluation of respiratory disorders such as COPD.

AIM

To compare serum uric acid levels in patients with stable Chronic Obstructive Pulmonary Disease and in patients with acute exacerbation (AE).

MATERIAL

Study Design: An observational cross sectional comparative study was conducted which included 25 stable COPD patients and 25 patients with AE of COPD, all of them aged more than 40 years. Serum UA levels were measured and compared between the two groups.

MATERIAL AND METHODS

Patients fulfilling inclusion criteria were included in the study after taking informed written consent. Blood sample was taken in plain vial and sent to Biochemistry lab for serum UA analysis. The analysis of serum UA was done using system reagent on Beckman Coulter AU Analyser. Complete blood count, blood urea, serum creatinine, arterial blood gas and oxygen saturation were also measured.

OBSERVATION AND RESULTS

The mean serum UA in the Stable group was 6.19 mg/dL and in AE group was 7.45 mg/ dL. There was a statistically significant difference between the 2 groups in terms of serum UA levels with a p value of 0.021 and the mean serum UA level being highest in the AE group. In this study, statistically significant difference was also found between Stable and AE group in terms of mMRC grading of dyspnea (p< 0.001), Pack years (p< 0.001), pH (p=0.009), pO2 (p< 0.001) and pCO2 (p< 0.001). There was no statistically significant difference between Stable and AE group in terms of age, gender, total leucocyte count, blood urea, serum creatinine and HCO3 Conclusion: Serum UA may be a useful parameter in assessing disease severity and hypoxemia in known COPD patients and may be helpful in early intensive management. Increased serum UA levels denote poor state and bad prognosis. Since serum UA is a simple, inexpensive and readily available routine laboratory test, it can be used in risk stratification in patients with COPD and can help in early management of patients with COPD.

Evaluation of rapid and standard tandem mass spectrometric methods to analyse veterinary drugs and their metabolites in antemortem bodily fluids from food animals

Antemortem bodily fluids can serve as an indicator of veterinary medicine exposure prior to food animal slaughter. A multi-residue, rapid screen electrospray ionisation mass spectrometric (RS-ESI-MS) method was developed to analyse 10 veterinary drugs or metabolites (clenbuterol, erythromycin, flunixin, 5-hydroxyflunixin, meloxicam, ractopamine, ractopamine-glucuronide, salbutamol, tylosin, and zilpaterol) in hog oral fluid and bovine urine. Simple acetonitrile extraction with salting-out was employed to remove the analytes from matrices in less than 30 minutes. Instrumental analysis time was < 1 min/injection. Regression coefficients of matrix-matched calibration curves ranged 0.9743-0.9999 across all compounds with limits of detection ranging from 0.46-108 ng mL^-1 for cattle urine and 0.19-64.4 ng mL^-1 for hog oral fluid across all analytes. Except for ractopamine-glucuronide, analyte recoveries ranged from 92.7-106% for oral fluid and urine fortified at 30, 100, and 300 ng mL^-1, with inter-day variations of < 25%. Ractopamine-glucuronide recovery was 93.3% for oral fluid fortified at 300 ng mL^-1. The RS-ESI-MS method accurately identified ractopamine and/or ractopamine-glucuronide in incurred cattle urine with results correlating well with traditional LC-MS/MS and HPLC fluorescence methods. As far as we are aware, this is the first report of the direct quantification of ractopamine-glucuronide from biological matrices without lengthy hydrolysis and cleanup steps.

Electrospray Ionization Inlet Tandem Mass Spectrometry: A Hyphenated Method for the Sensitive Determination of Chemicals in Animal Tissues and Body Fluids

This study demonstrates the utility of electrospray ionization inlet mass spectrometry (ESII-MS/MS) for the quantitative determination of analytes in complex animal matrices without chromatographic separation. Veterinary drugs including flunixin, its metabolite 5-hydroxyflunixin, and zilpaterol and persistent organic perfluoroalkyl compounds were determined in incurred plasma, urine, and/or tissue samples. Limits of detection (LOD) of zilpaterol in kidney, liver, lung, and muscle ranged from 0.02 to 0.06 ng/g, whereas the limit of quantitation (LOQ) for zilpaterol in all tissues was 0.1 ng/g. For urinary or plasma flunixin, 5-hydroxyflunixin, and PFOS/PFHxS, LODs ranged from 0.1 to 0.7 ng/mL while the LOQs ranged from 0.4 to 50 ng/mL. Regression coefficients for matrix-matched standard curves were 0.993-0.997, 0.977-0.999, and 0.999 for plasma, tissues, and urine, respectively. Correlations between quantitative results obtained by ESII-MS/MS and LC-MS for flunixin, 5-hydroxyflunixin, and zilpaterol ranged from 0.930 to 0.985. ESII-MS/MS provided rapid, sensitive, and accurate analyses of veterinary drugs and environmental contaminants from complex matrices without chromatographic separation.

Electrospray ionization rapid screening sans liquid chromatography column: A sensitive method for detection and quantification of chemicals in animal tissues and urine

RATIONALE

Electrospray ionization mass spectrometry (ESI-MS) in conjunction with liquid chromatography (LC) can provide accurate quantitative data, but it is not well-suited for the rapid screening (RS) of analytes incurred into complex matrices. This study was designed to determine the usefulness of ESI for rapid detection and quantitation of veterinary drugs from complex biological matrices under near real-time conditions.

METHODS

Nine veterinary drugs or metabolites, clenbuterol, erythromycin, flunixin, 5-hydroxyflunixin, meloxicam, ractopamine, salbutamol, tylosin and zilpaterol, present in cow urine, sheep urine, sheep tissues (kidney, muscle, liver and lung) or pig kidney, were simultaneously analyzed. A simple sample clean-up procedure, which included dilution with 10% sodium carbonate followed by extraction with ethyl acetate, was used. For tissues, an additional pre-extraction with hexane was performed to remove fat prior to MS analysis. Samples were introduced into the mass spectrometer through the LC autosampler, but no chromatographic separation was employed. A Sciex 5600+ triple time-of-flight mass spectrometer with a dual-spray source interfaced with a Shimadzu Nexera LC system was used. Samples were analyzed in positive ion mode.

RESULTS

Sample extraction times were typically 10-30 min or less and instrumental analysis time was 1 min/sample. Regression coefficients of matrix-matched standard curves across all compounds ranged from 0.9701-0.9999 in urine (cow and sheep) and tissues (sheep kidney, liver, lung, muscle and pig kidney). Limits of detection ranged from 0.11 to 2.03 ng/mL across analytes in urine and 0.11 to 8.86 ng/g across tissues. Correlations between RS-ESI-MS and LC/MS/MS results were 0.956 to 0.998 for incurred residues of flunixin in cow urine, ractopamine in pig kidney and zilpaterol in sheep urine.

CONCLUSIONS

RS-ESI-MS provided rapid, sensitive, and accurate analyses of nine veterinary drugs from complex matrices with very little sample preparation and produced quantitative data akin to LC/MS/MS.

Abstract P5-08-07: Study of diphenylamine analogs as inducers of mesenchymal to epithelial transition in breast cancer

The organization of cell cytoskeleton is altered in events of epithelial to mesenchymal transition (EMT), promotion of cell motility, and cancer metastases. EMT is associated with decreased cell-cell adhesion, downregulation of epithelial markers like E-Cadherin, cytokeratins, and occludins, and upregulation of mesenchymal markers such as N-cadherin, vimentin, and various transcription factors such as slug and ZEB. Epithelial to mesenchymal transition is also a consequence of drug resistance and is responsible for cancer metastases. Triple negative breast cancer is highly aggressive cancer and patients show poor prognosis and disease-free survival due to the lack of targeted therapy. Mitogen activated protein kinase pathway, including extracellular activated kinase ERK1/2 and ERK5, and phosphoinositide 3-kinase (PI3K) pathway are known to alter the cytoskeleton through the downstream activation of oncogenes such as FRA-1 and loss of focal adhesions. Of these pathways, the MEK5-ERK5 pathway is understudied in triple negative breast cancer TNBC, and there are few research tools available to selectively inhibit this pathway. The diphenylamine analogs were derived from the parent molecule Mekinist, a FDA approved MEK1/2 inhibitor for melanoma, and modified to gain selectivity towards MEK5. SC-1-151, a type-III allosteric inhibitor of MEK5 is a dual MEK1/2 (98.6%) and MEK5 (59%) inhibitor; the molecule inhibits cell viability and colony formation, and attenuates tumor growth.

SC-1-151 was serendipitously identified as a mesenchymal to epithelial transition activator in TNBC cell line MDA-MB-231. E-cadherin protein expression and cell morphology were examined to study MET after the treatment of MDA-MB-231 cells with different structural analogs of SC-1-151 after treatment for 5 days. The compound was further found to induce E-cadherin expression and epithelial phenotype in tamoxifen resistant estrogen positive MCF-7 cell line that underwent EMT. The compound is identified to promote this activity by targeting at least the ERK-FRA1-ZEB1 axis. Alkyl or N-Methyl piperazine substituents on the amide of ring 1 produced similar result as SC-1-151, and substituting the amide group with acid or ester also induced MET. In contrast, ortho-fluoro, para-iodo functional groups of the arene ring 2, when replaced with a meta-bromo substituent did not induce MET. We aim to test the compounds on EGF treated MDA-MB-468 cells to observe the attenuation of EGF induced EMT. Future studies will be performed to determine the specific protein interactions of the promising compounds.

Citation Format: Bhatt AB, Wright TD, Anna K, Gupta M, Chakrabarty S, Flaherty PT, Hoang V, Burow M, Cavanaugh JE. Study of diphenylamine analogs as inducers of mesenchymal to epithelial transition in breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-08-07.

Atmospheric Solid Analysis Probe and Modified Desorption Electrospray Ionization Mass Spectrometry for Rapid Screening and Semi-Quantification of Zilpaterol in Urine and Tissues of Sheep

Ambient ionization mass spectrometric methods including desorption electrospray ionization (DESI) and atmospheric solid analysis probe (ASAP) have great potential for applications requiring real-time screening of target molecules in complex matrixes. Such techniques can also rapidly produce repeatable semiquantitative data, with minimal sample preparation, relative to liquid chromatography-mass spectrometry (LC-MS). In this study, a commercial ASAP probe was used to conduct both ASAP-MS and modified DESI (MDESI) MS analyses. We conducted real-time qualitative and semiquantitative analysis of the leanness-enhancing agent zilpaterol in incurred sheep urine, kidney, muscle, liver, and lung samples using ASAP-MS and MDESI MS. Using ASAP, limits of detection (LOD) and quantitation (LOQ) in urine were 1.1 and 3.7 ng/mL, respectively, while for MDESI MS they were 1.3 and 4.4 ng/mL, respectively. The LODs for tissues were 0.1-0.4 ng/g using ASAP, and 0.2-0.6 ng/g with MDESI MS. The LOQs of the tissues in ASAP were 0.4-1.2 ng/g and 0.5-2.1 ng/g in MDESI MS. Trace levels of zilpaterol were accurately analyzed in urine and tissues of sheep treated with dietary zilpaterol HCl. The correlation coefficient ( R²) between semiquantitative ASAP-MS and MDESI MS results of urine samples was 0.872. The data from ASAP and MDESI MS were validated using LC-MS/MS; urinary zilpaterol concentrations ≥5.0 ng/mL or tissue zilpaterol concentrations ≥1.5 ng/g were detected by ASAP and MDESI MS, respectively, 100% of the time. Forty samples could be analyzed in triplicate, directly from biological matrixes in under an hour.

Comparison of Lateral Flow Assay, Kidney Inhibition Swab, and Liquid Chromatography-Tandem Mass Spectrometry for the Detection of Penicillin G Residues in Sow Urine

Sows (n = 126) were administered penicillin G; urine, collected at slaughter, was screened by kidney inhibition swab (KIS; 4 h testing time) and then stored at -80 °C (∼1200 days) until analysis by lateral flow assay (LF, ∼5 min testing time) and tandem quadrupole LC-MS/MS (TQ) analysis. The stability of penicillin in urine during storage was verified using TQ analyses. Quantitative results were well-correlated (R² = 0.98) with only a ∼10% decrease in penicillin concentration during the 3-year storage period. KIS retesting of stored samples returned results consistent with the original analyses. Lateral flow assay results were highly correlated with the KIS and TQ results. A KIS positive sample, which was not confirmed by TQ or LF, was assayed by Triple-TOF LC-MS to determine the cause of the apparent false positive. This study suggests LF can be used to quickly and efficiently screen for penicillin G residues before slaughter.

Case report on carotid body tumor

A 40 years old lady presented to us with the complaints of repeated attack of syncope with left sided neck swelling. Ultrasonography, Color Doppler study and arteriography were done which revealed a solid vascular mass in the carotid bifurcation. Mass was resected and histopathology was done. Histopathologic findings were typical of a carotid body tumour. As carotid body tumour is a rare disease. So, we are going to present this in this article.

Association of premature androgenetic alopecia and metabolic syndrome in a young Indian population

Context:

Although evidences for association of androgenetic alopecia (AGA) with metabolic syndrome (MetS) are accruing, inconclusiveness with respect to the gender specificity and differential association of MetS with increasing severity of AGA continues to persist. Furthermore, data specific to Indian settings are relatively sparse.

Aims:

The present study aimed at assessing the frequency of MetS in individuals with early AGA in Indian settings.

Settings and Design:

A case-control study was conducted at a trichology clinic in Bengaluru between April 2012 and September 2012 with a total of 85 cases of AGA and 85 age-matched controls.

Materials and Methods:

The Norwood-Hamilton classification was used to assess the grade of AGA. MetS was defined according to the National Cholesterol Education Program Adult Treatment Panel III criteria. Blood pressure, blood glucose, lipid parameters, and body mass index along with anthropometric measurements were assessed in all study participants.

Statistical Analysis Used:

Chi-square test was used to compare proportions between groups. Means were compared between groups using Student's t-test.

Results:

MetS was seen in a higher proportion of patients with AGA (43.5%) as compared to the control group (2.4%) and the differences were statistically significant (P < 0.001). As compared to controls, patients with AGA had higher triglycerides (P < 0.001), systolic blood pressure (P < 0.001), diastolic blood pressure (P < 0.001) along with significantly lower high-density lipoprotein cholesterol levels (P < 0.001). Severity of AGA was not associated with MetS.

Conclusions:

AGA is associated with MetS in male Indian patients aged <30 years. Studies with large sample sizes may be required to conclusively define any putative associations between AGA grades and MetS.

Percutaneous Coronary Intervention (PCI) of Chronic Total Occlusion (CTO) lesion in Bangladeshi patient population: a single center experience- In hospital and 90 days outcome

Objectives Aim of the study was to evaluate the primary in-hospital success and 90 days outcome of PCI in patients with CTO lesions, using either Bare-metal stents (BMS) or Drug Eluting Stent (DES) like Sirolimus-eluting or Paclitaxel-eluting stent. Methods Total 71 patients were included in this non-randomized prospective cohort as per the definition of CTO, from a total of 875 patients who had PCI at our center in the quantifying period. Total 92 stents were deployed in 71 patients. After the guide wire crossing and the balloon dilation, measurement of the culprit lesion were done by using Siemens QCA measuring system. Among the patients, Male: 59 and Female: 12. Mean age were for Male: 53yrs, for Female: 65yrs. Associated CAD risk factors were Dyslipidemia, High Blood pressure, Diabetes Mellitus, Positive FH for CAD and Smoking (all male). Results Our study shows 71 patients (8.1%) had CTO lesion out of total 875 PCI procedures. Among the study group; 56 (79%) were Dyslipidemic, 50 (70%) were hypertensive: 40 (56%) patients were Diabetic, 25 (42%) were all male smoker. Female patients were more obese (BMI M 26: F 27) and developed CAD in advance age. We found that the incidences of CTO lesions were more in LAD territory 27 (38%) followed by RCA 26 (37%) and LCX 18 (25%). Average length and diameter of stented vessel was greater in RCA than LAD and LCX. Stents used: BMS 34 (36.9%), Sirolimus 25 (27.2%), Paclitaxel 18 (19.6%), Biolimus 10 (10.8%) and Everolimus 5 (5.4%). Post procedural, in-hospital and 90 days out come was 100% in our present study. Conclusion Our study has revealed that PCI in patients with CTO lesion has shown good success rate in our hospital with no procedural complication both in-hospital and 90 days after, either treated with BMS or DES. DOI: http://dx.doi.org/10.3329/pulse.v5i1.20185 Pulse Vol.5 January 2011 p.19-26

General route to synthesize of metal (Ni, Co, Mn, Fe) oxide nanostructure and their optical and magnetic behaviour

Here we report a generalised way to prepare transitional metal (Ni, Co, Mn, Fe) oxide nanostructures via solvothermal route followed by controlled heat treatment. The method has been successfully involved to produce structurally uniform and well crystalline phase of the different metal (Ni, Co, Mn) oxide faceted nanoparticles and porous nanorods (Fe2O3) with highly anisotropic surfaces. The product materials were characterized by the X-ray powder diffraction and electron microscope (SEM, TEM) to investigate the structural and morphological details. Optical absorption study was carried out by UV-VIS spectrophotometer and the results are analysed on the basis of their electronic transitions of 3d shell and band energies. The details magnetic investigation was carried out by the measurement of magnetization with varying magnetic field and temperature. The observed magnetic behaviour is explained on the basis of uncompensated spins lying on the surface which is extremely anisotropic in the present systems of the synthesized materials.

Physical growth and nutritional status of Car Nicobarese and Moplah children of Andaman-Nicobar Islands in India

The objective of this cross-sectional study was to assess growth and nutritional status of Car Nicobarese children and compare it with Moplah children, who live in a similar environment. A total of 436 Car Nicobarese children and 438 Moplah children, aged 6-10 years, were selected for the study. The anthropometric measurements included stature, body weight, sitting height, bi-acromial breadth, bi-iliac breadth, mid-upper arm circumference, skinfold thickness of biceps, triceps and subscapular region. 50th percentile (median) growth curves were calculated among the studied children and compared with Centers for Disease Control and Prevention (CDC) 2000 reference. Z scores of weight for age (WAZ), height for age (HAZ) and BMI for age (BMIZ) were computed using growth references of the CDC 2000. It was observed that the Car Nicobarese children were shorter but heavier than Moplah children of both sexes all through the age range, which was also reflected in median value of anthropometric variables. Car Nicobarese children were nutritionally better compared to Moplah children based on the nutritional indices. The major differences between Car Nicobarese and Moplah children were found in their arm muscularity rather than arm adiposity. Overall, Car Nicobarese children were nutritionally in normal and better condition than Moplah children. However, present dietary change (intake of high calories and fat diet) of Car Nicobarese population may be reflected in the form of childhood obesity in the recent future, which has already been observed in their adult population.

Conformational preferences of furan- and thiophene-based arylamides: a combined computational and experimental study

We examine the conformational preferences of the furan- and thiophene-based arylamides, N-methylfuran-2-carboxamide (3) and N-methylthiophene-2-carboxamide (4), using a combination of computational methods and NMR experiments. The compound choice stems from their use as foldamer building blocks. We quantify the differences in the conformational rigidity of the two compounds, which governs corresponding foldamer conformations. Specifically, we demonstrate the effects of intramolecular hydrogen bonding (H-bonding), geometrical patterns and solvent polarity on arylamide conformations by comparing 3, 4 and previously studied ortho-methoxy N-methylbenzamide (1) and ortho-methylthio N-methylbenzamide (2). The study reveals that compound 3, despite its non-optimal S(5)-type H-bond geometry, retains a large portion of the H-bonded (eclipsed) conformation even in polar protic solvents. This behaviour is consistent with the quantum mechanical (QM) torsional energy profile. The percentages of H-bonded conformers that 3 retains are just slightly smaller than those of 1, which has a stronger S(6)-type H-bond. As for 2 and 4, the replacement of the O atom in 1 by an S atom in 2 results in a 70–90% loss of the H-bonded conformer in solution. However, the equivalent O to S replacement in 3 (leading to 4) causes only 15–30% loss of the eclipsed conformers in 4. Therefore, conformational preferences of 4 are very different from 2, in contrast to the similarity between 3 and 1. This study shows how the interplay of several forces modulates the conformational flexibility of arylamides. It also attests the strategy we are developing, which leads to accurate prediction of foldamer structure. The vital component of this strategy is the re-parameterization of critical force field parameters based on QM potential energy profiles, as well as validation of these parameters using experimental data in solution.

Electronic absorption spectrum of triacetylene cation for astronomical considerations

The A(2)Πg ← X(2)Πu electronic transition (4800-6000 Å) of triacetylene cation was measured in an ion trap, where the vibrational and rotational degrees of freedom were equilibrated to 25 K. The rotational profile of the origin band is predicted by a collisional-radiative rate model under conditions expected in diffuse interstellar clouds. Variation in the density of the surrounding gas, rotational temperature, and velocity dispersion are taken into account.

A new matrix assisted ionization method for the analysis of volatile and nonvolatile compounds by atmospheric probe mass spectrometry

Matrix assisted ionization of nonvolatile compounds is shown not to be limited to vacuum conditions and does not require a laser. Simply placing a solution of analyte dissolved with a suitable matrix such as 3-nitrobenzonitrile (3-NBN) or 2,5-dihydroxyacetophenone on a melting point tube and gently heating the dried sample near the ion entrance aperture of a mass spectrometer using a flow of gas produces abundant ions of peptides, small proteins, drugs, and polar lipids. Fundamental studies point to matrix-mediated ionization occurring prior to the entrance aperture of the mass spectrometer. The method is analytically useful, producing peptide mass fingerprints of bovine serum albumin tryptic digest consuming sub-picomoles of sample. Application of 100 fmol of angiotensin I in 3-NBN matrix produces the doubly and triply protonated molecular ions as the most abundant peaks in the mass spectrum. No carryover is observed for samples containing up to 100 pmol of this peptide. A commercial atmospheric samples analysis probe provides a simple method for sample introduction to an atmospheric pressure ion source for analysis of volatile and nonvolatile compounds without using the corona discharge but using sample preparation similar to matrix-assisted laser desorption/ionization.