Allergenic fungi spore records (15 years) and sensitization in patients with respiratory allergy in Thessaloniki-Greece.

BACKGROUND: The prevalence of respiratory allergy to fungi spores (FS) is not precisely known but is estimated at 20-30% of atopic patients. There are no aerobiological records, necessary for respiratory allergy diagnosis and treatment, in Thessaloniki and generally in Greece. AIM: Creation of a database on FS circulation and investigation of skin sensitivity (SS) of asthmatics by using skin prick tests (SPT). MATERIAL AND METHODS: Daily records and identification of 15 airborne FS species were conducted, using a Burkard trap during 1987-2001. SS to 5 most common FS extracts was investigated, by using SPT in a total of 1311 asthmatics with atopy, submitted to the Out-Patient Clinic of Asthma (Pulmonary Dept, Aristotle Univ, Thessaloniki) in 1990-2001. RESULTS: The FS recorded in the 15-year period were as follows: Cladosporium spp. (72.2%), Alternaria spp. (9.8%), Ustilago spp. (8.1%), Ascospores (2.7%), Agrocybe spp. (1.5%), Helminthosporium spp. (1.4%), Leptosphaeria spp (1.2%), Agrogybe spp. (1.1%), whereas the species Botrytis, Stemphylium, Pleospora, Nigrospora, Epicoccum. Fusarium, Torula and Phoma presented concentrations <1%. The highest numbers of airborne FS were recorded during summer. Positive skin reaction to FS was observed in 421 (32%) patients of the 1311 asthmatics. Positive skin reaction to Altemaria species was observed in 177 patients (13.5%), in 98 (7.4%) to Cladosporium, 65 (5%) to Aspergillus, 45 (3.4%) to Fusarium and 36 (2.7%) to Rhizopus. FS sensitivity is much more frequent in younger men. CONCLUSIONS: For the first time in Thessaloniki-Greece, 15 allergenic FS species circulation has been recorded for the last 15 years. SS was more frequently detected for the species of Alternaria, Cladosporium and Aspergillus.     

Seasonal distribution of Alternaria, Aspergillus, Cladosporium and Penicillium species isolated in homes of fungal allergic patients.

BACKGROUND: Allergy to airborne fungi can cause rhinitis and severe asthma, hence the exposure to spores inside home is an important factor of sensitization. The aim of this study was to determine the distribution and prevalence of species of Alternaria, Aspergillus, Cladosporium and Penicillium inside and outside of homes of patients allergic to fungi and to evaluate seasonal variations. METHODS: Air samples were collected in 22 selected homes of patients with allergy to fungi using a volumetric method of impacting plates with culture media. The isolated species were identified and statistical analysis of the presence of the four fungi was carried out. RESULTS: A total of 431 indoor and 150 outdoor exposed plates were cultured, leading to isolation of 11,843 colonies of fungi (range 0- 1 666 colony-forming units per cubic meter (CFUs/m(3)). 85.5% of total colonies belonged to the four genera considered. The highest presence of Aspergillus, Cladosporium and Penicillium in indoor environment was registered in autumn. Alternaria was more frequent in summer. In the outdoor environment, Penicillium was more abundant in winter and Aspergillus in summer (P= .002). The largest numbers of isolations were of Cladosporium and Penicillium during all four seasons, indoors as well as outdoors. Alternaria was present in all the homes studied both in summer and in autumn. The most prevalent species were: Alternaria alternata, Cladosporium herbarum, Cladosporium cladosporioides, Aspergillus niger and Penicillium chrysogenum. CONCLUSIONS: The quantitative analysis of the four taxa related with respiratory allergies demonstrated considerable seasonal variability. Statistical differences between the indoor and outdoor prevalence were detected only in Alternaria. In summer and autumn, the greater level of exposure to the four studied taxas occurred inside homes.     

Sensitization to Alternaria and Cladosporium in asthmatic patients and its in vitro diagnostic confirmation.

In order to determine the prevalence of airborne mould sensitization and the reliability of the in vitro diagnostic techniques in daily practice (antigen-specific IgE and histamine release test), we performed a 3-year study in 2,200 patients diagnosed with rhinosinusitis and/or bronchial asthma. We found mould sensitization in 101 patients, 20% of whom presented monosensitization against airborne moulds, and the rest associated other sensitizations as follows: 53.7% against Dermatophagoides pteronyssinus, 45% against grass pollen and 30% against Olea europea. The most frequently involved moulds in our patients were Alternaria and Cladosporium. Seventy-six percent of the patients presented sensitization against Alternaria, 56% of whom were monosensitized, 26% presented cosensitization to Cladosporium and the remainder were sensitive to more than two moulds. Regarding Cladosporium, the percentage of patients was similar (66%), although only 23% were monosensitized and 46% presented an associated sensitization against Alternaria. We also observed a correlation between skin tests and both in vitro diagnostic techniques, with a relative sensitivity of the specific IgE determination compared to the skin test of 98% against Alternaria and 90.4% against Cladosporium, whereas the relative sensitivity of the histamine release test was 97.4% for Alternaria and 85% for Cladosporium. In conclusion, we think that in order to confirm the etiopathogenesis of the airborne moulds and before an immunotherapy treatment is indicated, the positive skin reactions should be confirmed by means of reliable laboratory diagnostic techniques, such as antigen-specific IgE determination and histamine release test.     

Mold allergy: 25 years of indoor and outdoor studies in Belgium

Collecting atmospheric fungal spores in Brussels for 25 years revealed significant quantitative differences at three different levels: the total number of spores collected every year, the annual frequency rate of some species e.g. Cladosporium and Alternaria, the proliferation of some rare species according to weather conditions.     

Spore concentration in cities of the European Economic Community. II. Spores of Cladosporium and Alternaria

A comparative account of Alternaria and Cladosporium spore concentrations in four cities in the European Economic Community (EEC), is given for the years 1973 and 1974. Sijilar volumetric air sampling methods were employed in each of the cities, and concentrations of 3000 Cladosporium spores and 100 Alternaria spores/m3 were taken as the threshold concentrations for clinical significance. With Cladosporium, although highest concentrations were observed in Brussels, the differences were less marked at the other stations. Highest Alternaria concentrations were reocrded in Brussels, followed by London, Leiden and Munich. During the 2 years studied, the average number of days with spore concentrations greater than the threshold value for Cladosporium were 59 in Brussels, 36 in Leiden, 38 in London and 46 in Munich and for Alternaria, 48 in Brussels, 13 in Leiden, 33 in London and 5 in Munich.     

Infections due to Xylohypha bantiana (Cladosporium trichoides)

Thirty culture-documented cases of infection caused by Xylohypha bantiana (synonyms, Cladosporium bantianum, Cladosporium trichoides) were identified in the world literature; 26 cases involved the central nervous system (CNS) and most frequently presented as chronic headache followed by fever and hemiparesis. Phaeohyphomycosis due to X. bantiana occurs worldwide, predominantly in young males. Pharmacologic immunosuppression was not an important predisposing factor. However, four patients had a history of systemic nocardiosis or facial phaeohyphomycosis caused by Alternaria species. Chest radiography revealed no pulmonary infiltrates. Computed tomography of the brain demonstrated a mass defect, the frontal lobes being the most common sites of infection. Lumbar puncture usually demonstrated an elevated opening pressure, elevated cerebrospinal fluid protein level, hypoglycorrhachia, and cultures were negative. No preoperative clinical or laboratory features indicated CNS fungal infection. Complete neurosurgical resection of the lesion was the most important therapeutic intervention determining survival; systemic antifungal chemotherapy apparently did not influence outcome. The survival rate of 35% for all patients and of 45% for all neurosurgically treated patients was higher than had previously been reported, probably because patients dying from infections confirmed only histopathologically were excluded.     

Aerobiological diagnosis of respiratory allergy by a personal sampler: two case reports.

We describe two cases of respiratory allergy (asthma), which were difficult to diagnosis from an etiological viewpoint. The routine diagnostic tests were not able to determine the causal allergens, although the clinical history suggested that allergens were confined to restricted environments. Therefore, an aerobiological sampling by means of a battery-powered portable device was carried out. This approach allowed identification of the responsible allergens, which were Alternaria spores in one case and thuja pollen in the other. Once a targeted environmental care had been performed, the patients' symptoms rapidly improved and antiasthma therapy could be stepped down or discontinued. We suggest that, in selected cases of difficult diagnosis the presence of proximity allergens is suspected, aerobiological sampling with a portable device should be considered.     

A study of the aeromycoflora of Cádiz: relationship to anthropogenic activity.

We describe a quantitative and qualitative study of the fungal spores found in the air of Cádiz during 1989 using a Cour-type trap. The results of this study can be extrapolated to other coastal cities of southern Europe with a Mediterranean climate. The spores identified have been classified into 25 taxonomic categories. The most abundant were Cladosporium, Chaetomium and Ustilago, and the most frequent, in addition to those mentioned, were Alternaria, Ascophyta and Venturia. The great abundance of Cladosporium is in accordance with the coastal situation of the city. Cladosporium, Alternaria, Curvularia and Stemphylium reached maximum concentrations jointly in October, 1989. They showed mutual cross-reactions. Ustilago and Nigrospora appeared during the period of cereal harvesting and storage.     

Concentration of allergic fungi spores in the air of flats in Lódź

The real contribution of moulds to the pathogenesis of allergic diseases remains unknown, although positive skin prick tests and/or specific serum IgE to moki allergens can be detected in 1-5% of atopic patients. A significant problem in assesment of exposure to mould allergens, resulting with difficulty in standarization of methods. The aim of this work was to assess the concentration of spores of 8 mould species in flats inhabited by peoples who Bont show any symptoms of allergy. The Open Petri Dish (OPD) method involving sedimentation of participles contained in the column of air over the dish was used to assess the number of spores in 1 m3 of indoor atmospheres. All colonies were counted, but only 8 mould species implicated in inhaled allergy were identified, ie.: Alternaria tenuis, Cladosporium herbarum, Helminthosporum halodes, Pullularia pullulans, Penicillium notatam, Rhizopus nigricans, Mucor mucedo, Aspergillus fumigatus. The tests were carried out in 10 flats located in various quarters of the cify of Lod? during three consecutive days of September 1995 between 5:00 pm and 6:04 pm. In analyzing the percentage of spores of each of the eight mould species tested we determined that, independent of fiat and test day, C. herbarum predominated. It is good agreement with the observations of other authors who report that among large quantities of fungi that are detected in late summer, usually C. herbarum spores dominate. This is the season when the incidence of the Cladosporium spores in the atmospheric air increases. Spores of H. halodes were detected least frequently. Our study demonstrated the presence of substantial amounts of mould spores in indoor air of houses in Lód?. The spores belong to species with documented allergenicity, suggesting that they may play a role in development of allergic sensitization in susceptible subjects.     

Airborne fungi in indoor and outdoor of asthmatic patients' home, living in the city of sari

The aim of this study was identification of fungi in indoor and outdoor of asthmatic patients home environment. Opened plates (containing of Malt extract agar media) were used for isolation of fungi in the air of indoor (n=360) and outdoor (n=180) of 90 asthmatic patients home living in the city of Sari at the level of breathing height. Plates were incubated in room temperature for 7-14 days. Then grown fungi were identified by standard mycological techniques.A total of 1876 colonies with 31 and 1692 colonies with 27 genera of fungi were identified from indoor and outdoor of asthmatic patients' home respectively. The most common fungi isolated were Cladosporium, Aspergillus and Penicillium. Stachibotyris, Oedocephalum, and Stemphillium showed the least frequencies among the isolated fungi.Cladosporium, Aspergillus, Penicillium, and Alternaria as the most common allergenic moulds had the most frequencies in indoor air of the houses of asthmatic patients.     

Prerequisites for lack of age differences in memory performance

Abstract

Free recall performance of young and old adults was examined in three memory tasks: a) acts carried out by the subjects (subject-performed tasks or SPTs), b) sentences with imagery instructions, and c) sentences. The subjects were presented with the same verbal information in all three tasks. No age differences were observed on free recall of SPTs, whereas typical aging effects were obtained on free recall of the other tasks. This way the data from a previous study of no age effects on SPT recall were replicated. A hypothesis about imagery as a critical factor for the lack of age differences on SPT recall gained no support. Two main concepts were proposed to account for the data: Compensation among the elderly by means of the multimodal and rich properties of SPTs, and a superior ability for a spontaneous recoding of verbal information among young adults. The results were also discussed in relation to a presumption of memory tasks as varying in attentional demands.     

上海市西南部气传致敏真菌消长规律

目的研究上海市全年大气真菌孢子的数量变化规律及其与气象因素之间的关系。方法使用重力沉降法（曝片法）收集真菌孢子,记录气象参数,取得数据录入计算机,使用SPSS软件包和Excel 2010进行统计学分析。将曝片中发现的优势菌种交链孢霉分离,置于不同温度下培养,使用Excel 2010分析其生长与温度之间的关系。结果上海市西南部地区空气中全年都有真菌孢子飘散,5和6月份日均观察到的气传真菌孢子数目最多,12、1和2月份最少。全年曝片共收集到真菌孢子5602个,其中交链孢霉（Alternaria）2669个（47.6%）、黑孢子菌（Negrospora Sphoric）1439个（25.7%）、匍柄霉（Stemphylium）215个（3.8%）、镰刀菌（Fusarium）199个（3.6%）、棒孢霉（Corynespora cassiicola）166个（3.0%）、弯孢霉（Curvularia）132个（2.4%）、附球菌（Epicoccum）125个（2.2%）、大孢枝孢霉（Cladosporium macrocarpum Preuss）122个（2.2%）、尾孢霉（Ceveospora）112个（2.0%）、蠕孢霉（Helminthosporium halodes）110个（2.0%）等。空气中真菌孢子数量与气象因素的偏相关性分析结果为：温度的偏相关系数为0.388,P〈0.001;天气情况为-0.152,P=0.006;风向为0.102,P=0.063;湿度为0.053,P=0.337;风力为0.051,P=0.352。对优势菌种交链孢霉进行分离培养,交链孢霉在不同温度下培养8d后的菌落直径分别为：12.5mm（4℃）,14mm（10℃）,31.5mm（15℃）,43mm（20℃）,63mm（25℃）,63mm（30℃）,33.5mm（35℃）,3.5mm（40℃）。结论交链孢霉和黑孢子菌是上海市西南部空气中的优势菌种。温度是与空气中真菌数量相关性最大的因素,25～30℃可能为交链孢霉以及大部分气传真菌的生长最适温度。天气状况也与气传真菌孢子数量有显著的相关性,而其他气象因素,如湿度、风向、风力与空气中真菌数量无显著相关性。     

Clinical characteristics,treatment outcomes,and occurrence of diabetes mellitus after pancreatic resection of solid pseudopapillary tumor in children and adolescents: A single institution experience with 51 cases

BackgroundSolid pseudopapillary tumors (SPTs) are rare, but they comprise the majority of pediatric pancreatic neoplasms. However, studies on these conditions in pediatric patients are lacking. The aim of this study was to investigate the clinical characteristics and treatment outcomes in children and adolescents with SPTs.MethodsThis retrospective study included 51 patients with SPTs who had undergone pancreatic tumor resection before the age of 19 years at Samsung Medical Center in Korea (from November 1994 to August 2020). We investigated the postoperative outcomes.ResultsOf the 51 patients with SPTs (female, 88.2%), the median age at diagnosis was 14 years (range, 8–19). The most common symptom was abdominal pain (60.8%), and 14 patients (27.5%) were asymptomatic. The median maximal tumor diameter was 7 cm (range, 1.4–14), and the pancreatic body and/or tail were involved in 68.6% of patients. The short-term complication rate was 21.5%, and the recurrence rate was 5.9%. New-onset diabetes mellitus (NODM) occurred in four patients.ConclusionsThe ideal treatment for SPTs is complete resection of the tumor; however, long-term postoperative complications including NODM should be monitored carefully, particularly in children and adolescents.     

Hypersensitivity to molds in New York City in adults who have asthma.

Molds have been linked epidemiologically to asthma as a key aeroallergen in several studies. Other allergens such as cockroach have been linked to asthma in New York City (NYC). To our knowledge, however, the pattern of mold hypersensitivity has never been examined systematically in the NYC area. Thus, we sought to determine the association between mold hypersensitivity and asthma in a large group of ambulatory patients evaluated for allergic disease for the years 1993 through 2001 at a single medical center. Serological testing for mold-specific immunoglobulin E (IgE) as well as IgE specific for other aeroallergens was performed and the associations between allergen-specific IgE and the presence of asthma were examined using bivariate and multivariate analysis. Factor analysis showed that three distinct groupings of aeroallergen-specific IgE existed within the panel of allergens used. Group 1 consisted of cat dander and dust mites (Dermatophagoides farinae). Group 2 consisted of tree, grass, and ragweed pollen. Group 3 consisted of the Deuteromycetes molds, Alternaria tenuis, Aspergillus fumigatus, and Cladosporium herbarum. Patients with asthma had a highly significant increase in the incidence of hypersensitivity to cat/dust mites and to the molds. Multivariate analysis showed that the presence of hypersensitivity to either A. tenuis or C. herbarum had a significant independent association with asthma after adjustment for cat/dust mite hypersensitivity and after adjustment for other clinical factors. On the other hand, pollen hypersensitivity was not associated independently with asthma. Mold hypersensitivity was strongly correlated with hypersensitivity to cat or dust mites in patients who did not have asthma but not in patients who did have asthma. In the NYC area, recent pollen and spore counts show that mold spores are measurable in at least 75% of the year. Thus it is conceivable that mold hypersensitivity plays a contributing and independent role in initiating or perpetuating the allergic response in patients with asthma in the New York area.     

The association of methamphetamine use and cardiomyopathy in young patients

Purpose

Methamphetamine is the most widespread illegally used stimulant in the United States. Previously published case reports and series suggest a potential association between methamphetamine exposure and cardiomyopathy. The objective of this study is to demonstrate an association between methamphetamine use and cardiomyopathy.

Subject and Methods

Case-control study based on chart review of discharges from a tertiary care medical center from January 2001 to June 2004. Patients were ≤45 years old. Cases included patients with a discharge diagnosis of either cardiomyopathy or heart failure. Controls included hospitalized patients who had an echocardiographic assessment of left ventricular function with ejection fraction ≥55% and no wall motion abnormalities.

Results

One hundred and seven cases and 114 controls were identified. Both groups had similar gender distribution, length of hospital stay, rates of health insurance, prevalence of coronary artery disease, diabetes mellitus, hypertension, cigarette smoking, alcohol abuse, and marijuana and cocaine use. Cases were older than controls (mean age: 38 vs 35 years; P=.008), had higher body mass index (BMI) (mean BMI: 37 vs 30 kg/m²; P<.001), and higher prevalence of renal failure (13% vs 4.4%; P=.03). Methamphetamine users had a 3.7-fold increased odds ratio [95% confidence interval, 1.8-7.8] for cardiomyopathy, adjusting for age, body mass index, and renal failure.

Conclusions

Methamphetamine use was associated with cardiomyopathy in young patients.     

Flowers of Cypripedium fargesii (Orchidaceae) fool flat-footed flies (Platypezidae) by faking fungus-infected foliage

Charles Darwin was fascinated by the orchid-pollinator interactions, but he did not realize that many orchid species are pollinated by deceit. Cypripedium, a model lineage of nonrewarding orchid flowers, is pollinated primarily by bees. Here we present both an example of floral mimesis of fungus-infected foliage in orchids and an example of flat-footed flies (Agathomyia sp.; Platypezidae) as pollen vectors for angiosperms. Cypripedium fargesii is a nectarless, terrestrial, endangered orchid from southwestern China that requires cross-pollination to produce the maximum number of viable embryos. All insects caught entering or leaving the labellum sac were Agathomyia sp. carrying conidia of Cladosporium sp. on their mouthparts and legs, suggesting mycophagy. Blackish hairy spots on the upper surface of foliage may imitate black mold spots, serving as short-term visual lures. Some odor molecules also associated with Cladosporium cultures were isolated in the floral scent. Mimesis of fungus-infected foliage probably represents an overlooked but important option in angiosperm diversification, because there are three to five more Cypripedium spp. in southwestern China with the same mode of floral presentation and black-spotted hairy leaves.     

The Friction of Structurally Modified Isotactic Polypropylene

The purpose of studies was to analyse an impact of heterogeneous nucleation of modified isotactic polypropylene (iPP) on its tribological properties. The iPP injection molded samples, produced by mold temperature of 20 and 70 °C, were modified with compositions of two nucleating agents (NA’s), DMDBS creating α-form and mixture of pimelic acid with calcium stearate (PACS) forming β–phase of iPP, with a total content 0.2 wt.% of NA’s. A polymorphic character of iPP, with both, monoclinic (α) and pseudo-hexagonal (β) crystalline structures, depending on the NA’s ratio, was verified. The morphology observation, DSC, hardness and tribological measurements as test in reciprocating motion with “pin on flat” method, were realized, followed by microscopic observation (confocal and SEM) of the friction patch track. It was found that Shore hardness rises along with DMBDS content, independent on mold temperature. The friction coefficient (COF) depends on NA’s content and forming temperature—for upper mold temperature (70 °C), its value is higher and more divergently related to NA’s composition, what is not the case by 20 °C mold temperature. The height of friction scratches and the width of patch tracks due to its plastic deformation, as detected by confocal microscopy, are related to heterogeneous nucleation modified structure of iPP.     

Airborne fungi isolated from Fortaleza city, State of Ceará, Brazil

Airbone fungi are considered important causes of allergic rhinitis and allergic asthma. The knowledge of these fungi in a city or region is important for the ecological diagnosis and specific treatment of allergic manifestations induced by inhalation of fungal allergens. The airborne fungi of Fortaleza, State of Ceará, Brazil, were studied during a one year period. Five hundred and twenty Petri dishes with Sabouraud dextrose agar medium were exposed at ten different locations in the city. The dishes exposed yielded one thousand and five hundred and twenty one colonies of twenty four genera. The most predominants were: Aspergillus (44.7%), Penicillium (13.3%), Curvularia (9.8%), Cladosporium (6.8%), Mycelia sterilia (6.0%), Fusarium (3.5%), Rhizopus (3.1%), Drechslera (2.6%), Alternaria (2.4%) and Absidia (2.2%). The results shown that Aspergillus, Penicillium, Mycelia sterilia, Fusarium and Alternaria were found during all months in the year. Absidia was more frequent during the dry season. Anemophilous fungi and the high concentration of spores in the air are important because may result in an increased number of people with allergic respiratory disease.     

Halogen immunoassay, a new method for the detection of sensitization to fungal allergens; comparisons with conventional techniques.

BACKGROUND: Accurate diagnosis of allergy to specific fungal species is confounded by the variability in allergens occurring with different diagnostic systems. We compared the halogen immunoassay (HIA), which uses allergens expressed by freshly germinated spores that are bound to protein binding membranes (PBM), with the commercial Pharmacia UniCap assay (CAP) and with skin prick tests (SPT). METHODS: Serum from 60 subjects was used; 30 were SPT positive and sensitized to at least one of Alternaria alternata or Aspergillus fumigatus and the other 30 were SPT negative to these fungi but known to be sensitized to non-fungal allergens. All sera were analyzed by CAP against A. alternata, A. fumigatus, Cladosporium herbarum and Epicoccum purpurascens. For HIA, spores from reference cultures belonging to these four species were germinated on PBM, laminated and then probed with each serum. Two independent observers using an ordinal ranking system quantified the intensity and occurrence of the resultant immunoglobulin E (IgE) immunostained haloes around spores and this was statistically compared with the results of the two conventional immunodiagnostic techniques. RESULTS: Germinated conidia of each species expressed detectable allergen in the HIA. The agreement between the ordinal rank scores assigned by the pair of observers was very good (k >or= 0.8) and only differed for A. fumigatus (k = 0.66) . Between 3% and 7% of SPT negative sera was identified by HIA to have specific IgE towards A. fumigatus and A. alternata. For all four species tested there were strong correlations between HIA and CAP (P < 0.0001). However the correlation of both HIA and CAP to SPT was weaker for A. alternata (r(s) = 0.44, P < 0.0153) and absent for A. fumigatus. CONCLUSIONS: Overall, the HIA is a new immunodiagnostic technique for the detection of sensitization to fungal allergens that correlates significantly with CAP and to a lesser extent with SPT. This may be due to extract variability and system differences. The significance of this derives from the unique ability of the HIA to measure IgE antibodies to the undegraded allergens that are actively secreted by germinating conidia and hyphae. These are the natural agents of exposure to fungi, and as such, are most likely to be relevant to clinical disease.     

Comparison of effects of the tyrosine kinase inhibitors AG957, AG490, and STI571 on BCR-ABL--expressing cells, demonstrating synergy between AG490 and STI571

STI571 (formerly CGP57148) and AG957 are small molecule inhibitors of the protein tyrosine kinase (PTK) p145(abl) and its oncogenic derivative p210(bcr-abl). AG490 is an inhibitor of the PTK Janus kinase 2 (JAK2). No direct comparison of these inhibitors has previously been reported, so this study compared their effects on factor-dependent FDC-P1, 32D, and MO7e cells and their p210(bcr-abl)-expressing factor-independent derivatives. STI571 was a more potent inhibitor of (3)H-thymidine incorporation in p210(bcr-abl)-expressing cells than was AG957, and it showed superior discrimination between inhibitory effects on parental cell lines and effects on their p210(bcr-abl)-expressing derivatives. Assays performed with and without growth factor demonstrated that STI571 but not AG957 reversed the p210(bcr-abl)-driven factor independence of cell lines. p210(bcr-abl)-expressing cells were less sensitive to AG490 than to AG957 or STI571. However, for p210(bcr-abl)-expressing clones from all 3 cell lines, synergistic inhibition was demonstrated between STI571 and concentrations of AG490 with no independent inhibitory effect. Inhibition of nucleic acid synthesis with AG957 treatment was associated with reduced cell numbers, reduced viability, and small pyknotic apoptotic cells. At concentrations of STI571 that reversed the p210(bcr-abl) factor-independent phenotype, STI571 treatment and growth factor deprivation together were sufficient to induce apoptosis. This study concludes that, for the cell lines studied, (1) STI571 is a more potent and more selective inhibitor of a p210(bcr-abl)-dependent phenotype than AG957; (2) AG490 synergizes with STI571 to enhance its inhibitory effect on p210(bcr-abl)-driven proliferation; and (3) the combination of p210(bcr-abl)-tyrosine kinase inhibition and growth factor signal withdrawal can be sufficient to induce apoptotic death of transformed cells. (Blood. 2001;97:2008-2015)