RESUMO
Paramphistomosis can lead to morbidity and mortality of ruminant livestock within tropical and sub-tropical climates. In recent decades, rumen fluke has become an emerging infection in temperate climates across Western Europe, with Calicophoron daubneyi, the primary species present. Clinical outbreaks with C. daubneyi larvae are reported and adults might be responsible for production losses. There is not currently a widely licensed anthelmintic product available to control C. daubneyi. In this study, three existing flukicide anthelmintics were tested for efficacy against mature C. daubneyi, comparing a standard in vitro culturing assay and a new more relevant rumen fluid based in vitro compound screening protocol. The new rumen based screen confirmed that oxyclozanide was active against adult C. daubneyi and identified activity with praziquantel. The study highlighted the downstream value of incorporating relevant in vitro screening for anthelmintic discovery pipelines.
Assuntos
Antiplatelmínticos/farmacologia , Oxiclozanida/farmacologia , Paramphistomatidae/efeitos dos fármacos , Testes de Sensibilidade Parasitária/veterinária , Praziquantel/farmacologia , Animais , Meios de Cultura , Microscopia Eletrônica de Varredura , Paramphistomatidae/ultraestrutura , Testes de Sensibilidade Parasitária/métodosRESUMO
When measuring the internally deposited activity in the bone of a subject, the placement of the detector is critical. This study reports the simulated counting efficiencies for three counting geometries, the skull, knee and shin, using 13 different voxel phantoms. It shows that the range of counting efficiencies for a given geometry is large for the studied phantoms, especially at low energies. Skull counting offers higher efficiency for low energies such as the 17 keV compared to knee counting or shin counting, but this advantage disappears when the energy is higher such as at 185 keV. This work also shows that the calibration phantom may greatly impact the accuracy of the activity estimate in bone counting, with uncertainties increasing greatly as the photon energy is reduced. Estimating the activity of a radionuclide in bone from direct counting has large uncertainties, and the dose calculated from a skeleton measurement would need careful analysis and, if possible, supporting data from other bioassay measurements.
Assuntos
Osso e Ossos/efeitos da radiação , Imagens de Fantasmas , Radioisótopos/análise , Contagem Corporal Total/métodos , Adulto , Carga Corporal (Radioterapia) , Calibragem , Simulação por Computador , Feminino , Humanos , Joelho/efeitos da radiação , Perna (Membro)/efeitos da radiação , Pulmão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Método de Monte Carlo , Fótons , Crânio/efeitos da radiação , SoftwareAssuntos
Transplante de Células-Tronco de Sangue do Cordão Umbilical , Éxons/genética , Cadeias beta de HLA-DQ/genética , Sequência de Bases , Feminino , Alemanha , Teste de Histocompatibilidade , Humanos , Masculino , Dados de Sequência Molecular , Polimorfismo de Nucleotídeo Único , Alinhamento de Sequência , Doadores de Tecidos , População BrancaRESUMO
Chemical standards are used to calibrate ion mobility spectrometers (IMS) for accurate and precise identification of target compounds. Research over the past 30 years has identified several positive and negative mode compounds that have been used as IMS standards. However, the IMS research community has not come to a consensus on any chemical compound(s) for use as a reference standard. Also, the reported K(0) values for the same compound analyzed on several IMS systems can be inconsistent. In many cases, mobility has not been correlated with a mass identification of an ion. The primary goal of this work was to provide mass-identified mobility (K(0)) values for standards. The results of this work were mass-identified K(0) values for positive and negative mode IMS chemical standards. The negative mode results of this study showed that TNT is a viable negative mode reference standard. New temperature-dependent K(0) values were found by characterizing drift gas temperature and water content; several examples were found of temperature-dependent changes for the ion species of several standards. The overall recommendation of this study is that proposed IMS standards should have temperature-dependent K(0) values quoted in the literature instead of using a single K(0) value for a compound.
RESUMO
Antibodies against the human neutrophil antigens (HNA) are able to stimulate transfusion reactions, autoimmune and neonatal neutropenia. The aim of this study was to determine the HNA allele frequencies in the largest ethnic minority group in Germany in comparison with the German population for predicting the risk of alloimmunization and associated transfusion reactions, as well as the risk of developing neonatal neutropenia for the newborn of racial mixed couples. However, there exists no data about HNA genotype distribution in Turkish population. DNA was isolated from blood samples of 119 German and 118 Turkish blood donors and typed them for HNA-1, -3, -4, and -5 by using a commercial polymerase chain reaction kit with sequence-specific primers (SSP-PCR) and compared the HNA genotype distribution of both groups. In German blood donors, the gene frequencies for HNA-1a and HNA-1b were 0.391 and 0.601, for HNA-3a and -3b, 0.744 and 0.256, for HNA-4a and -4b, 0.908 and 0.092, and for HNA-5a and -5bw, 0.731 and 0.269. In Turkish blood donors, we observed 0.420/0.564, 0.737/0.263, 0.881/0.119, and 0.754/0.246 for HNA-1a/1b, -3a/3b, -4a/4b, and -5a/5bw. No statistic significant difference between genotypes in these populations was observed. This study is the first to report HNA gene frequencies in a Turkish population. It showed that there is no difference of HNA genotype in blood donors with Turkish descent in comparison with German blood donors. The alternating transfusion of blood and blood components is no increased risk for developing alloantibodies against HNA antigens. In pregnancy of mixed couples no special screening programs for HNA are necessary.
Assuntos
Alelos , Doadores de Sangue , Frequência do Gene , Genótipo , Isoantígenos/genética , Neutrófilos , Incompatibilidade de Grupos Sanguíneos/genética , Incompatibilidade de Grupos Sanguíneos/imunologia , Incompatibilidade de Grupos Sanguíneos/prevenção & controle , Feminino , Alemanha , Humanos , Isoanticorpos/genética , Isoanticorpos/imunologia , Isoantígenos/imunologia , Masculino , Gravidez , População Branca/etnologia , População Branca/genéticaRESUMO
The novel allele HLA-B*07:68:02 identified in two related individuals of Caucasian origin is described.
Assuntos
Sangue Fetal/imunologia , Antígenos HLA-B/genética , Teste de Histocompatibilidade/métodos , Alelos , Sequência de Bases , Doadores de Sangue , Éxons , Pai , Feminino , Alemanha , Antígeno HLA-B7 , Humanos , Imunogenética , Masculino , Dados de Sequência Molecular , Reação em Cadeia da Polimerase/métodos , Polimorfismo GenéticoRESUMO
BACKGROUND: The effect of gamma irradiation on leucoreduced red-blood-cells (RBCs) stored in an additive solution (AS) containing phosphate, adenine, glucose, guanosine, saline and mannitol (PAGGS-M) has not yet been studied, and there are different recommendations about storage time of leucoreduced RBCs after irradiation. STUDY DESIGN AND METHODS: We studied 63 leucoreduced RBC units. All RBCs were stored in AS PAGGS-M and leucoreduced on the collection day. Twenty-one components were irradiated on Day +14 with 30 Gy and 22 served as non-irradiated controls. Samples were drawn and analysed from these 43 units on Day +7, +14, +21, +28, +35, +42 and +49 from the collection day. From 20 units, no samples were taken earlier than on Day +49. Of these, 10 components had been irradiated on Day +14 with 30 Gy and 10 served as non-irradiated controls. RESULTS: Gamma irradiation induced an enhanced in vitro haemolysis rate in the irradiated components. One of the irradiated units showed a haemolysis rate over the recommended limit of 0·8% on Day +42 and four on Day +49. The leakage of potassium ions from irradiated RBCs started to increase faster than that of unirradiated RBCs from the day of irradiation. Lactate dehydrogenase levels increased faster in irradiated units 3 weeks after irradiation. We showed that taking samples weekly does not affect the final result. CONCLUSIONS: Our findings show that the European recommendations should not be changed in regard to the limitation of the storageability after irradiation of leucoreduced RBCs. The damage after irradiation and storage cannot be prevented by using the high-quality AS PAGGS-M.
Assuntos
Preservação de Sangue , Eritrócitos/metabolismo , Eritrócitos/efeitos da radiação , Raios gama , L-Lactato Desidrogenase/metabolismo , Potássio/metabolismo , 2,3-Difosfoglicerato/metabolismo , 2,3-Difosfoglicerato/efeitos da radiação , Adenina , Trifosfato de Adenosina/metabolismo , Trifosfato de Adenosina/efeitos da radiação , Contagem de Células Sanguíneas , Índices de Eritrócitos/efeitos da radiação , Glucose , Guanosina , Hemólise/efeitos da radiação , Humanos , Concentração de Íons de Hidrogênio/efeitos da radiação , L-Lactato Desidrogenase/efeitos da radiação , Manitol , Fosfatos/metabolismo , Fosfatos/efeitos da radiação , Potássio/efeitos da radiaçãoRESUMO
BACKGROUND: There exists only few data on in vitro and in vivo effects of gamma irradiation of leucoreduced red blood cells (RBCs). Reported studies reflect the effects of early irradiation and subsequent storage. The effects of irradiation on RBCs shortly before the end of their shelf-life have not been examined. STUDY DESIGN AND METHODS: We studied 160 RBC units that were stored in the additive solution saline-adenine-glucose-mannitol and leucoreduced on the collection day. Forty components were irradiated on day +14 with 30 Gy, 40 on day +28, 40 on day +35, and 40 served as nonirradiated controls. In vitro evaluation of all units was performed on days +3, +7, +14, +21, +28, +35, and +42 from the collection day. RESULTS: Gamma irradiation induced leakage of potassium ions and lactate dehydrogenase and enhanced in vitro haemolysis rate in the irradiated components, which started to increase faster than that of nonirradiated RBCs from the day of irradiation, i.e. from day +14 in units that were irradiated on day +14, from day +28 in units that were irradiated on day +28, and from day +35 in units that were irradiated on day +35. CONCLUSIONS: This study presents data on the in vitro quality of leucoreduced RBCs that have been irradiated on days +14, +28, or +35 after collection. Our findings support the proposal that the current limitation of the age of RBCs on the day of gamma irradiation may be replaced by staged limitations depending on the time of irradiation.
Assuntos
Preservação de Sangue/métodos , Eritrócitos/efeitos da radiação , Raios gama , Adenina , Glucose , Hemólise/efeitos da radiação , Humanos , Procedimentos de Redução de Leucócitos , Manitol , Permeabilidade/efeitos da radiação , Cloreto de Sódio , Fatores de TempoRESUMO
OBJECTIVE: Besides foetal or maternal disorders, placental dysfunction is a major cause of intrauterine growth restriction (IUGR). Although numerous macro- and histopathological changes have been described, little is known about the precise aetiology and the contribution of foetal/placental genes in this disorder. DESIGN: Placental tissues of 20 IUGR and control neonates were analysed by microarray technique. Four of the regulated genes with possible relevance in the pathogenesis of IUGR and its consequences were further studied in placentas of 27 IUGR and 35 control newborns. RESULTS: Elevated gene expression of leptin, corticotrophin-releasing hormone (CRH), and IGF-binding protein-1 (IGFBP-1) in IUGR placentas could be confirmed in the larger group by real-time PCR, whereas prolactin showed no significant difference. Accordingly, protein expression of leptin and IGFBP-1 depicted by Western blot was elevated in IUGR, prolactin was not different. Birthweight standard deviation score (SDS) correlated negatively to leptin, IGFBP-1, and CRH, whereas placental weight correlated only to IGFBP-1. Leptin correlated negatively to gestational age of IUGR patients and positively to placental score, a marker of severity of impaired foeto-placental circulation. CONCLUSIONS: As confirmed in a large group of IUGR and control samples, the up-regulated factors leptin, IGFBP-1, and CRH may serve as candidate genes for the prediction of subsequent metabolic consequences in IUGR newborns. These three factors may not only influence growth of the foetus, but might also interact with programming of its metabolic functions, which has to be determined in an ongoing study.
Assuntos
Retardo do Crescimento Fetal/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Placenta/metabolismo , Adulto , Western Blotting , Feminino , Retardo do Crescimento Fetal/genética , Humanos , Recém-Nascido , Leptina/metabolismo , Masculino , Gravidez , Radioimunoensaio , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adulto JovemRESUMO
The Lawrence Livermore National Laboratory (LLNL) Torso phantom, which is the de facto standard for lung counter calibration for low energy photon emitters, has undergone a number of revisions since its development. The first generation used real human bone: the second generation used synthetic bone and had a major design change; the third generation had more subtle material and mould changes. This work has compared a first generation, two second generation, and two third generation LLNL phantoms to see if there are any differences between the phantoms. The comparison of five LLNL phantoms using the same counting regions has shown that the second and third generation phantoms are essentially equivalent at low photon energies, but the first generation phantom shows an increased counting efficiency at low photon energies due to a design flaw. It is also apparent that these phantoms have maintained their performance characteristics over an extended period of time.
Assuntos
Imagens de Fantasmas/normas , Radiometria/métodos , Absorciometria de Fóton , Osso e Ossos/anatomia & histologia , Calibragem , Estudos de Avaliação como Assunto , Germânio , Humanos , Laboratórios , Músculos/anatomia & histologia , Tórax/anatomia & histologiaRESUMO
A joint project between the Human Monitoring Laboratory (HML) and the Ottawa Hospital has measured the retention of 131I in patients who have received the radioiodine diagnostically. Thirty-nine subjects with intact thyroid glands and nine athyreotic subjects were measured in the HML's whole-body/thyroid counter to determine the retention of 131I following its medical administration. The average biological half-life of 131I in 26 euthyroid subjects was found to be 66.1+/-6.3 days which may he statistically significantly lower than the ICRP recommended value of 80 days. Nine hyperthyroid patients had a mean biological half-life of 38.2+/-8.6 days and in three hypothyroid patients the corresponding value was 29.3+/-8.8 days. Thyroid 131I uptake was measured in a conventional clinical fashion at the Ottawa Hospital Civic campus 24 h after oral administration of the radioiodine using a collimated thick sodium iodide detector placed over the neck anteriorly. Measured values were 10.144+/-0.009, 0.314+/-0.035 and 0.045+/-0.010 of the administered dose in euthyroid, hyperthyroid and hypothyroid patients respectively. The euthyroid range at the hospital is 0.06 - 0.22. Uptake was significantly lower for the euthyroid group than the ICRP value of 0.3. The radioiodine retention in athyreotic subjects followed a two compartment model with biological half-lives of 1.0+/-1.2 days and 18.4+/-1.1 days.
Assuntos
Radioisótopos do Iodo/farmacocinética , Glândula Tireoide/efeitos da radiação , Tireoidectomia , Adulto , Idoso , Transporte Biológico , Feminino , Meia-Vida , Humanos , Radioisótopos do Iodo/química , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Distribuição TecidualRESUMO
During the course of an intercomparison exercise it was possible to compare two JAERI phantoms with each other by using a multi-energy photon emitting lung set (241Am/152Eu). One belonged to the IAEA (Vienna), the other belonged to the Human Monitoring Laboratory (Ottawa). The intercomparison of the phantoms showed that they were statistically distinct from each other, although the differences were small. The counting efficiencies varied from each other by about 4% at 17 keV and 2% at photon energies above 17 keV. It was concluded that these difference were either due to small variations of chest wall thickness during the manufacturing process or positioning errors. The intercomparison also revealed a serious problem with one of the overlay plates of the HML's phantom. The adipose mass fraction of the overlay plate was found to be much greater (approximately 40%) than the manufacturer's stated value (10%).
Assuntos
Imagens de Fantasmas/normas , Radiometria/normas , Germânio , Humanos , Japão , PulmãoRESUMO
The Human Monitoring Laboratory has measured the chest wall thickness and adipose mass fraction of a group of workers at a Canadian uranium refinery, a conversion plant, and a fuel fabrication site using ultrasound. A site-specific biometric equation has been developed for these workers, who seem to be somewhat larger than other workers reported in the literature. Chest wall thickness is a very important modifier on lung counting efficiency and these data have been put into the perspective of the impending Canadian dose limits that will reduce the limit of occupationally exposed workers to 100 mSv in a 5-y period with a maximum of 50 mSv in any one year. The sensitivity of the germanium and phoswich based lung counting systems have been compared. Over a range of chest wall thickness of 1.6 cm to 6.0 cm and using a 30-min counting time, the achievable MDA's lie in the range of 6.7 mg to 19.1 mg or 6.7 mg to 30 mg with a two-phoswich-detector array or a germanium lung counting system, respectively. Depending on chest wall thickness, these achievable MDA's are close to, or exceed, the predicted amounts of natural uranium that will remain in the lung (absorption type M and S) after an intake equivalent to the Annual Limit on Intake that corresponds to 20 mSv. Neither system is sufficiently sensitive to detect an intake of Type S natural uranium in a worker with a chest wall thickness that corresponds to the average (3.73 cm) if it occurred more than 7 d prior to the lung count.
Assuntos
Exposição Ocupacional , Tórax/anatomia & histologia , Urânio , Adulto , Carga Corporal (Radioterapia) , Humanos , Indústrias , Masculino , Saúde Ocupacional , Doses de Radiação , Tórax/efeitos da radiaçãoRESUMO
Lung counters for in vivo detection of low energy photon emitters are typically calibrated using phantoms containing lung tissue equivalent material with the radioactivity homogeneously distributed throughout the material. If the activity in a measurement subject is heterogeneously distributed, the activity estimate for that subject will be uncertain due to the assumptions of distribution. The magnitude of the uncertainty for a four-detector germanium array, using the Lawrence Livermore National Laboratory torso phantom with a newly designed lung set that allows the activity to be localized in one or more of 16 areas, was estimated. The results show that detector arrays will reduce the uncertainties arising from the geometry of the lung deposition compared to single detectors. The estimated activity of an internal deposition that emits 17.5 keV photons can be overestimated by a factor of three, or underestimated by a factor of infinity (i.e., the activity is missed completely). As the photon energy rises to 59.5 keV the uncertainty in the activity decreases so that the maximum overestimate (underestimate) will be a factor of two (five). As the energy rises to 344.3 keV only the maximum underestimate changes: it becomes a factor of three.
Assuntos
Pulmão/efeitos da radiação , Radiometria/instrumentação , Humanos , Doses de RadiaçãoRESUMO
The performance characteristics of sliced lung sets were compared to lung sets with activity homogeneously distributed throughout the lung tissue substitute material. The activity estimate from planar sources differs from the estimate from homogeneous sources by a factor of 0.88 to 1.09 depending on the photon energy. This error is small compared to other uncertainties commonly encountered in lung counting, i.e., activity deposition in the lung, detector placement, size difference between individuals, etc. Sliced lung sets could be used instead of homogeneous lung sets to test or provide an interim calibration for a lung counting system.
Assuntos
Imagens de Fantasmas/normas , Radiometria/normas , Calibragem , Germânio , Humanos , Pulmão , Radiometria/métodosRESUMO
The development of the Drosophila compound eye requires the function of a set of evolutionarily conserved genes. Among these, the Drosophila Pax-6 gene eyeless (ey) plays a major role. ey has been considered a master control gene of eye development in the animal kingdom because targeted expression of ey and vertebrate as well as invertebrate homologs lead to the formation of ectopic eyes in Drosophila. We demonstrate that an intron of the ey gene contains an enhancer that regulates the eye specific expression of the gene in the eye disc primordia of embryos and in the eye imaginal discs of third instar larvae. Moreover, a 212-bp enhancer element is necessary and sufficient for the enhancer function. It is partially conserved in Drosophila hydei and contains putative Pax-6 Paired domain binding sites. We show that several binding sites are required for the eye specific expression, and, therefore, we propose a Pax-6-like molecule to be a positive transactivator for the eye specific ey expression. This transactivator recently has been identified as twin of eyeless, the second Pax-6 gene in Drosophila.
Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Drosophila , Drosophila/embriologia , Elementos Facilitadores Genéticos/genética , Olho/crescimento & desenvolvimento , Proteínas de Homeodomínio , Animais , Sequência de Bases , Sítios de Ligação/genética , Drosophila/crescimento & desenvolvimento , Proteínas do Olho , Regulação da Expressão Gênica no Desenvolvimento/genética , Genes Reporter/genética , Hibridização In Situ , Proteínas de Insetos/genética , Íntrons/genética , Larva/crescimento & desenvolvimento , Dados de Sequência Molecular , Mutação/genética , Fator de Transcrição PAX6 , Fatores de Transcrição Box Pareados , Proteínas Repressoras , Mapeamento por Restrição , Análise de Sequência de DNA , Ativação Transcricional/genéticaRESUMO
The Human Monitoring Laboratory has compared the LLNL and JAERI torso phantoms using its germanium detector lung counting system by measuring the counting efficiencies for radioactive materials in the phantoms at photon energies of 17.7 keV, 59.5 keV, 121.8 keV, and 344 keV to assess the similarity (or differences) in performance characteristics. The counting efficiencies obtained from the two phantoms were compared by converting the Chest Wall Thickness data and Adipose Mass Fractions of the phantoms to Muscle Equivalent Chest Wall Thicknesses. The counting efficiencies for the two phantoms were found to be within a factor of 1.44 of each other at 17.7 keV, 1.30 at 59.5 keV, 1.25 at 121.8 keV, and 1.17 at 344 keV when using a four detector array (JAERI efficiency divided by LLNL efficiency). However, individual detector responses show that the counting efficiencies from the two phantoms differ considerably in the region of the heart (up to a factor of 6 at 17 keV). Other areas above the lungs give counting efficiencies that are similar to each other. A routine intercomparison exercise with Cameco Corporation has shown that the counting efficiencies derived from the LLNL and JAERI phantoms were found to be within a factor of 1.18 (JAERI/LLNL) when a natural uranium lung set was used to calibrate a lung counter consisting of phoswich detectors. This work has also shown that over the energy range 63 keV-185 keV the LLNL phantom can be used to calibrate phoswich detector systems that are positioned on the back of the subject.
Assuntos
Imagens de Fantasmas/normas , Monitoramento de Radiação/normas , Germânio , Coração , Humanos , Pulmão , Músculos/anatomia & histologia , Monitoramento de Radiação/instrumentação , TóraxRESUMO
Vertebrate and invertebrate eye development require the activity of several evolutionarily conserved genes. Among these the Pax-6 genes play a major role in the genetic control of eye development. Mutations in Pax-6 genes affect eye development in humans, mice, and Drosophila, and misexpression of Pax-6 genes in Drosophila can induce ectopic eyes. Here we report the identification of a paired-like homeobox gene, DRx, which is also conserved from flies to vertebrates. Highly conserved domains in the Drosophila protein are the octapeptide, the identical homeodomain, the carboxyl-terminal OAR domain, and a newly identified Rx domain. DRx is expressed in the embryo in the procephalic region and in the clypeolabrum from stage 8 on and later in the brain and the central nervous system. Compared with eyeless, the DRx expression in the embryo starts earlier, similar to the pattern in vertebrates, where Rx expression precedes Pax-6 expression. Because the vertebrate Rx genes have a function during brain and eye development, it was proposed that DRx has a similar function. The DRx expression pattern argues for a conserved function at least during brain development, but we could not detect any expression in the embryonic eye primordia or in the larval eye imaginal discs. Therefore DRx could be considered as a homolog of vertebrate Rx genes. The Rx genes might be involved in brain patterning processes and specify eye fields in different phyla.
Assuntos
Encéfalo/crescimento & desenvolvimento , Proteínas de Drosophila , Drosophila/genética , Proteínas do Olho , Olho/crescimento & desenvolvimento , Genes Homeobox , Proteínas de Homeodomínio/química , Proteínas de Homeodomínio/genética , Fatores de Transcrição , Sequência de Aminoácidos , Animais , Sequência de Bases , Encéfalo/embriologia , Sequência Conservada , Drosophila/embriologia , Drosophila/crescimento & desenvolvimento , Indução Embrionária , Olho/embriologia , Genes de Insetos , Proteínas de Homeodomínio/biossíntese , Humanos , Camundongos , Dados de Sequência Molecular , Mapeamento por Restrição , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Transcrição Gênica , VertebradosRESUMO
A new aerosol sampling method, utilizing a porous curved surface as the sampling inlet, has recently been developed. Previous laboratory evaluations of this method have demonstrated its important features, such as low wind sensitivity and good filter collection uniformity. In this study a prototype incorporating the new method was evaluated in the field as a stationary and personal sampling device. The small sampler, utilizing a 25-mm filter is called the button aerosol sampler and was evaluated for collecting total airborne dust and fungal spores. The study was performed in nine poorly maintained inner-city houses during environmental cleanups at different cleanliness levels. The button sampler was used in parallel with the standard 37-mm closed-face filter cassette. Four collocated samplers of each type were tested at all sites as stationary samplers, and three samplers of each type were tested at two sites as personal samplers. Aerosol samples were collected on filters and analyzed using the gravimetric method for total dust and epifluorescence microscopy for fungal spores. The average particle concentration values measured with the button sampler and with the standard sampling cassette were found to correlate well within ranges of 10(1)-10(3) micrograms/m3 for total dust and 10(3)-10(5) spores/m3 for airborne fungi. The measurement results obtained with the new button sampler showed lower intersample variations of the measured concentration levels and higher uniformity of the particle deposits on the filters than those obtained with the standard cassette.