Formaldehyde gas inactivation of Bacillus anthracis, Bacillus subtilis, and Geobacillus stearothermophilus spores on indoor surface materials

AIMS

To evaluate the decontamination of Bacillus anthracis, Bacillus subtilis, and Geobacillus stearothermophilus spores on indoor surface materials using formaldehyde gas.

METHODS AND RESULTS

B. anthracis, B. subtilis, and G. stearothermophilus spores were dried on seven types of indoor surfaces and exposed to approx. 1100 ppm formaldehyde gas for 10 h. Formaldehyde exposure significantly decreased viable B. anthracis, B. subtilis, and G. stearothermophilus spores on all test materials. Significant differences were observed when comparing the reduction in viable spores of B. anthracis with B. subtilis (galvanized metal and painted wallboard paper) and G. stearothermophilus (industrial carpet and painted wallboard paper). Formaldehyde gas inactivated>or=50% of the biological indicators and spore strips (approx. 1x10(6) CFU) when analyzed after 1 and 7 days.

CONCLUSIONS

Formaldehyde gas significantly reduced the number of viable spores on both porous and nonporous materials in which the two surrogates exhibited similar log reductions to that of B. anthracis on most test materials.

SIGNIFICANCE AND IMPACT OF THE STUDY

These results provide new comparative information for the decontamination of B. anthracis spores with surrogates on indoor surfaces using formaldehyde gas.

Broiler performance and carcass characteristics when fed diets containing lysine maize (LY038 or LY038 x MON 810), control, or conventional reference maize

Lysine maize (Zea mays), LY038, was developed through the application of modern biotechnology to accumulate free Lys in the germ portion of maize grain and provide an alternative to direct addition of supplemental Lys to poultry diets. Maize LY038 x MON 810 was produced by conventional breeding of LY038 with MON 810, which provides the corn plant protection against feeding damage from the European corn borer. A 42-d broiler feeding study (10 pens of 10 male Cobb x Cobb 500 broilers/treatment) was conducted to compare the feeding value of grain from LY038 or LY038 x MON 810 to that of a conventional control (similar genetic background to the test maize) and 5 conventional maize hybrids. The LY038 and LY038 x MON 810 maize-based diets and control and conventional reference maize-based diets supplemented with l-Lys HCl were formulated to a Lys level below that required for optimal bird performance, whereas all other essential amino acids were present at levels, relative to Lys, above those required for optimal bird performance [1.05% and 0.90% total Lys (as-fed) for d 0 to 21 and d 21 to 42, respectively]. Total Lys level in control and reference maize-based diets without supplemental l-Lys HCl was formulated to be 0.079% lower than supplemented diets. Weight gain, feed efficiency, and carcass yield and composition of broilers fed diets containing LY038 or LY038 x MON 810 were not different (P > 0.05) from that of broilers fed l-Lys HCl-supplemented diets and were superior (P < or = 0.05) to that of broilers fed conventional maize diets without supplemental l-Lys HCl. Both broiler performance and carcass data demonstrate that the bioefficacy of the incremental Lys in LY038 or LY038 x MON 810 grain was not different from that of Lys in conventional maize diets supplemented with l-Lys HCl. Thus, LY038 and LY038 x MON 810 can be considered as wholesome as and more nutritious than conventional maize due to its higher-than-average Lys content.

Systematic variations in polymer gel dosimeter calibration due to container influence and deviations from water equivalence

There are a number of gel dosimeter calibration methods in contemporary usage. The present study is a detailed Monte Carlo investigation into the accuracy of several calibration techniques. Results show that for most arrangements the dose to gel accurately reflects the dose to water, with the most accurate method involving the use of a large diameter flask of gel into which multiple small fields of varying dose are directed. The least accurate method was found to be that of a long test tube in a water phantom, coaxial with the beam. The large flask method is also the most straightforward and least likely to introduce errors during the set-up, though, to its detriment, the volume of gel required is much more than other methods.

Decontamination assessment of Bacillus anthracis, Bacillus subtilis, and Geobacillus stearothermophilus spores on indoor surfaces using a hydrogen peroxide gas generator

AIMS

To evaluate the decontamination of Bacillus anthracis, Bacillus subtilis, and Geobacillus stearothermophilus spores on indoor surface materials using hydrogen peroxide gas.

METHODS AND RESULTS

Bacillus anthracis, B. subtilis, and G. stearothermophilus spores were dried on seven types of indoor surfaces and exposed to > or =1000 ppm hydrogen peroxide gas for 20 min. Hydrogen peroxide exposure significantly decreased viable B. anthracis, B. subtilis, and G. stearothermophilus spores on all test materials except G. stearothermophilus on industrial carpet. Significant differences were observed when comparing the reduction in viable spores of B. anthracis with both surrogates. The effectiveness of gaseous hydrogen peroxide on the growth of biological indicators and spore strips was evaluated in parallel as a qualitative assessment of decontamination. At 1 and 7 days postexposure, decontaminated biological indicators and spore strips exhibited no growth, while the nondecontaminated samples displayed growth.

CONCLUSIONS

Significant differences in decontamination efficacy of hydrogen peroxide gas on porous and nonporous surfaces were observed when comparing the mean log reduction in B. anthracis spores with B. subtilis and G. stearothermophilus spores.

SIGNIFICANCE AND IMPACT OF THE STUDY

These results provide comparative information for the decontamination of B. anthracis spores with surrogates on indoor surfaces using hydrogen peroxide gas.

Comparison of broiler performance when fed diets containing corn grain with insect-protected (corn rootworm and European corn borer) and herbicide-tolerant (glyphosate) traits, control corn, or commercial reference corn--revisited

A 42-d feeding experiment with growing Ross x Ross 508 broilers showed that the nutritional value of insect-protected and herbicide-tolerant corn was comparable to that of the genetically similar control and 5 commercial reference corn hybrids. MON 88017 provides protection from feeding damage by coleopteran pest corn rootworm and is tolerant to the action of glyphosate, the active ingredient in the Roundup family of agricultural herbicides. MON 88017 x MON 810 was developed by the traditional breeding of MON 88017 with MON 810, which provides protection from the European corn borer and other lepidopteran pests. A randomized complete block design was used with 8 dietary treatments in each of 5 replicated blocks of pens. No differences among diets were observed (P > 0.05) in performance (final live weights, feed intake, feed conversion, and adjusted feed conversion), carcass yield (chill, fat pad, breast, thigh, wing, and drum weight), or percentage of moisture, protein, and fat in breast meat and moisture and fat in thigh meat. Thigh protein was similar (P > 0.05) in broilers fed diets containing MON 88017 x MON 810 and conventional control or all commercial reference corns; however, differences (P < 0.05) were noted for the percentage of thigh protein among broilers fed the control and 2 of the 5 reference diets, attributable to biological variability among the conventional corn hybrids. Broilers overall performed consistently and had similar carcass yield and meat composition when fed diets containing MON 88017 or MON 88017 x MON 810 as compared with those fed the conventional control and commercial diets, supporting a conclusion of nutritional equivalence.

Comparison of broiler performance when fed diets containing corn grain with insect-protected (corn rootworm and European corn borer) and herbicide-tolerant (glyphosate) traits, control corn, or commercial reference corn

A 42-d feeding experiment with growing Ross x Ross 508 broilers showed that the nutritional value of insect-protected and herbicide-tolerant corn was comparable to that of the genetically similar control and 5 commercial reference corn hybrids. MON 88017 provides protection from feeding damage by coleopteran pest corn rootworm and is tolerant to the action of glyphosate, the active ingredient in the Roundup family of agricultural herbicides. MON 88017 x MON 810 was developed by the traditional breeding of MON 88017 with MON 810, which provides protection from the European corn borer and other lepidopteran pests. A randomized complete block design was used with 8 dietary treatments in each of 5 replicated blocks of pens. No differences among diets were observed (P > 0.05) in performance (final live weights, feed intake, feed conversion, and adjusted feed conversion), carcass yield (chill, fat pad, breast, thigh, wing, and drum weight), or percentage of moisture, protein, and fat in breast meat and moisture and fat in thigh meat. Thigh protein was similar (P > 0.05) in broilers fed diets containing MON 88017 x MON 810 and conventional control or all commercial reference corns; however, differences (P < 0.05) were noted for the percentage of thigh protein among broilers fed the control and 2 of the 5 reference diets, attributable to biological variability among the conventional corn hybrids. Broilers overall performed consistently and had similar carcass yield and meat composition when fed diets containing MON 88017 or MON 88017 x MON 810 as compared with those fed the conventional control and commercial diets, supporting a conclusion of nutritional equivalence.

[First isolation of Histoplasma capsulatum from the urban bat Eumops bonariensis]

We report the first isolation of Histoplasma capsulatum var. capsulatum from a male bat Eumops bonariensis captured in Buenos Aires city in 2003. The pathogen was recovered from spleen and liver specimens, and was identified by its phenotypic characteristics. PCR with primers 1283, (GTG)5, (GACA)4 and M13 was used to compare both bat isolates with 17 human isolates, 12 from patients residing in Buenos Aires city, and 5 from other countries of the Americas. The profiles obtained with the four primers showed that both bat isolates were identical to each other and closer to Buenos Aires patients than to the other isolates (similarity percentage: 91-100% and 55-97%, respectively). The high genetic relationship between bat isolates and those from patients living in Buenos Aires suggests a common source of infection. This is the first record of E. bonariensis infected with H. capsulatum in the world, and the first isolation of the fungus in the Argentinean Chiroptera population. In the same way as these wild mammals act as reservoir and spread the fungus in the natural environment, infection in urban bats could well be associated with the increase in histoplasmosis clinical cases among immunosuppressed hosts in Buenos Aires city.

Histoplasma capsulatum yeast cells attach and agglutinate human erythrocytes

The ability of yeast cells of Histoplasma capsulatum to attach and agglutinate human erythrocytes has been described. This is the first report involving these yeasts in the hemagglutination phenomenon. Results revealed that the yeast cells were able to bind to erythrocytes irrespective of blood groups and to agglutinate them when a high density of yeast cells was used. Assays on the inhibition of yeast attachment to erythrocytes were also performed, using sugar-treated yeast cells. Results indicate that galactose (Gal), mainly the beta-anomer, specially inhibited yeast attachment. Disaccharides (Gal-derivatives) and glycosaminoglycans containing Gal residues, mainly chondroitin sulfate C, promote this type of inhibition. In addition, preliminary data of inhibition assays also involved a probable ionic strength driven mechanism mediated by sialic acid and heparan sulfate, suggesting that yeast binding to erythrocytes could be associated with negative charges of both molecules.

Comparison of broiler performance when fed diets containing roundup ready (event RT73), nontransgenic control, or commercial canola meal

A 42-d experiment compared the nutritional value of genetically modified glyphosate-tolerant (Roundup Ready event RT73) canola meal to that of conventional canola meal when fed to rapidly growing Ross x Ross 508 broilers using a randomized complete block design. Five pens of males and 5 pens of females were used in each of 8 canola meal treatments (glyphosate-tolerant, nontransgenic control, and 6 commercial varieties). Broilers (10 birds/pen) were fed approximately 25% wt/wt canola meal during the first 20 d and 20% wt/wt canola meal thereafter. In general, performance response variables for glyphosate-tolerant canola meal were not different (P > 0.05) than those for the nontransgenic and commercial canola meals. Carcass fat pad, breast meat, thighs, legs, and wings (on a percentage basis) were similar across treatments (P > 0.05). Expressed as percentage of live weight, chill weight of the broilers fed diets containing glyphosate-tolerant canola meal was not different from those fed all other diets, but some differences were observed between the nontransgenic control and commercial diets. No major differences were observed in percentage of moisture, protein, and fat in breast or thigh meat (P > 0.05) across treatments. Comparisons of the glyphosate-tolerant canola diet to the population of all other diets (combining sexes) showed no major differences (P > 0.05) in performance, carcass yields, or moisture, protein, and fat in breast and thigh meat. Broilers fed diets containing glyphosate-tolerant canola meal had similar growth performance to birds fed nontransgenic control and commercial canola diets.

Comparison of broiler performance when fed diets containing grain from YieldGard Rootworm (MON863), YieldGard Plus (MON810 × MON863), nontransgenic control, or commercial reference corn hybrids

Two 42-d experiments compared the nutritional value of YieldGard Rootworm corn (MON863; experiment 1) and YieldGard Plus corn (MON810 x MON863; experiment 2) to their respective nontransgenic controls and 6 commercial reference corn hybrids when fed to growing broilers. For each experiment, a randomized complete block design was used with 8 dietary treatments in each of 5 replicated blocks of pens. In experiment 1, no differences among diets were observed (P > 0.05) for final live weights and feed conversion. Broilers fed diets containing MON863 corn had adjusted feed conversion similar to the nontransgenic control and the population of control and commercial diets. On a weight basis, there were no differences among diets for chill, fat pad, and thigh, drum, and wing weights. Differences (P < 0.05) between MON863 and commercial corn diets were noted for breast meat, chill and thigh, drum, and wing weights on a percentage of weight basis. No differences were observed (P > 0.05) in the percentage of moisture, protein, and fat in breast meat or thigh meat across treatment diets. In experiment 2, there were no significant differences among diets for all broiler performance and carcass parameters evaluated. Broilers overall performed consistently and had similar carcass yields and meat compositions when fed diets containing MON863 corn or MON810 x MON863 corn as compared with their respective nontransgenic control and commercial diets, supporting a conclusion of similar feeding values among diets.

Comparison of broiler performance when fed diets containing grain from YieldGard (MON810), YieldGard x Roundup Ready (GA21), nontransgenic control, or commercial corn

This 42-day experiment was undertaken to compare the nutritional value of insect-protected corn event MON810 (YieldGard) and YieldGard x herbicide-tolerant corn event GA21 (Roundup Ready) to their nontransgenic controls as well as four different commercial reference corns, when fed to growing Cobb x Cobb broilers. A randomized complete block design was used, and each treatment was replicated with five pens of males and five pens of females with 10 broilers per pen. Broilers were fed approximately 55% wt/wt corn during the first 20 d and approximately 60% wt/wt corn thereafter. The corn component of diets fed to broilers was supplied entirely with grain from the eight hybrids included in the experiment. Final live weights averaged 2.09 kg/bird fed YieldGard corn and 2.15 kg/bird fed YieldGard x Roundup Ready corn and were not different (P > 0.05) from final weights for birds fed control or commercial corn. Feed conversion was not affected (P > 0.05) by YieldGard (1.72) or YieldGard x Roundup Ready (1.77) corn feeding when compared with the feeding of other corn diets. Chill weights, fat pad, thigh weights, and wing weights were not affected by diets (P > 0.05). Differences (P < 0.05) were noted for breast and drum weights across treatments. Broilers overall performed consistently and had similar carcass yield and meat composition when fed diets containing YieldGard (event MON810) or YieldGard (event MON810) x Roundup Ready (event GA21) as compared with their nontransgenic controls and commercial diets.

Comparison of broiler performance when fed diets containing grain from roundup ready (NK603), yieldgard x roundup ready (MON810 x NK603), non-transgenic control, or commercial corn

Two 42-d experiments compared the nutritional value of the glyphosate-tolerant corn event NK603 (Roundup Ready corn) (experiment 1) and the combined traits, insect-protected corn event MON 810 (YieldGard com) x glyphosate-tolerant corn event NK603 (experiment 2) to their respective non-transgenic controls and to commercial reference corn, when fed to growing broilers. For each experiment, a randomized complete block design was used with eight dietary treatments in each of five replicated blocks of pens (eight pens for males and eight pens for females per block). Final live weights and feed conversion were not different (P > 0.05) across all treatments in both experiments. In experiment 1, broilers fed diets containing Roundup Ready corn had similar feed conversion adjusted for mortalities to those fed the non-transgenic control and one of the commercial corn diets. Chill weights and thigh, drum, and wing weights were not affected by diets. Differences (P < 0.05) were noted for breast meat and fat pad weights across treatments. In experiment 2, the adjusted feed conversion and carcass parameters were not affected by diets. Differences (P < 0.05) were noted only for protein content of breast meat. Differences observed in both experiments were consistent with natural variability. Broilers in general performed consistently and had similar carcass yields and meat compositions when fed diets containing Roundup Ready corn or YieldGard x Roundup Ready corn as compared with their respective non-transgenic control and commercial diets supporting similar feeding values among diets.

Attempts to detect transgenic and endogenous plant DNA and transgenic protein in muscle from broilers fed YieldGard Corn Borer Corn

Questions regarding the digestive fate of DNA and protein from transgenic grain have been raised in regard to human consumption and trade of animal products (e.g., meat, milk, and eggs) from farm animals fed transgenic crops. Using highly sensitive, fully characterized analytical methods, fragments of transgenic and endogenous plant DNA, as well as transgenic protein, were not detected in chicken breast muscle samples from animals fed YieldGard Corn Borer Corn event MON 810 (YG). Total DNA was extracted from breast muscle samples from chickens fed for 42 d with a diet including either 55 to 60% YG grain or 55 to 60% conventional corn grain. DNA preparations were analyzed by PCR followed by Southern blot hybridization for the presence of a 211-bp fragment of the Bacillus thuringiensis (Bt) cry1Ab gene and a 213-bp fragment of the endogenous corn gene sh2 (encoding ADP glucose pyrophosphorylase). By using 1 microg of input DNA per reaction, none of the extracted samples was positive for cry1Ab or sh2 at the limit of detection for these PCR assays. A 396-bp fragment of the chicken ovalbumin (ov) gene, used as a positive control, was amplified from all samples showing that the DNA preparations were amenable to PCR amplification. By using a competitive immunoassay with a limit of detection of approximately 60 ng of CrylAb protein per gram of chicken muscle, neither the CrylAb protein nor immunoreactive peptide fragments were detectable in the breast muscle homogenates from chickens fed YG grain.

An Imported Case ofBlastomyces DermatitidisInfection in Mexico

Blastomycosis is an acute or chronic primary infection of the respiratory system, endemic in North America (United States of America and Canada), Africa and Asia. We report a case in Mexico, in a three years old child who had been born in California and lived in Chicago, U.S.A. The patient presented pulmonary symptoms prior to development of a skin ulcer. Blastomyces dermatitidis was identified by mycological and molecular procedures. The patient was successfully treated with amphotericin B, oral ketoconazole and itraconazole.

The prevalence of aspirin intolerant asthma (AIA) in Australian asthmatic patients

BACKGROUND

Aspirin intolerant asthma (AIA) is a clinically distinct syndrome characterised by the precipitation of asthma attacks following the ingestion of aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs). The prevalence of AIA among Australian asthmatic patients has not previously been reported.

METHODS

Three populations were surveyed to establish the prevalence of AIA among Australian asthmatics. Two surveys were completed in patients recruited from the metropolitan area in Perth, Western Australia, one comprising 150 recruited from hospital based sources (hospital cohort) and the second comprising 366 from the membership of the Asthma Foundation of Western Australia (Asthma Foundation cohort). In a third study 1298 individuals were randomly selected from the rural community of Busselton in Western Australia.

RESULTS

The prevalence of AIA in the hospital and Asthma Foundation cohorts was found to be 10.7% and 10.4%, respectively. Univariate analyses in the Asthma Foundation cohort indicated that AIA was associated with more severe asthma (OR = 2.4, 95% CI 1.18 to 4.86), nasal polyposis (OR=3.19, 95% CI 1.52 to 6.68), atopy (OR=2.96, 95% CI 1.48 to 5.89), sulfite sensitivity (OR=3.97, 95% CI 1.87 to 8.41), and sensitivity to wine (OR=3.27, 95% CI 1.65 to 6.47). Multivariate analyses indicated that atopy (OR=2.80, 95% CI 1.38 to 5.70), nasal polyposis (OR=3.39, 95% CI 1.57 to 7.29), and the number of asthma attacks in the previous 12 months (OR=1.20, 95% CI 1.02 to 1.42) were independent predictors for AIA, as was wine sensitivity (OR=2.20, 95% CI 1.02 to 4.72). The prevalence of AIA among asthmatic patients in the Busselton cohort was 10.9%. In addition, 2.5% of non-diagnosed asthmatics in this cohort reported asthma symptoms following aspirin ingestion.

CONCLUSION

The prevalence of respiratory symptoms triggered by aspirin/NSAID use was found to be 10-11% in patients with asthma and 2.5% in non-asthmatics. Aspirin sensitivity appears to be a significant problem in the community and further investigations of the mechanisms of these responses and the possible link between this syndrome and other food and chemical sensitivities are required.

Psychosocial challenges in transplantation

The authors review the psychosocial aspects of transplantation. They first review psychosocial risk factors that place transplant patients at higher risk for noncompliance and negative outcomes. They then discuss what assessments should be included in a pretransplantation psychosocial evaluation. Goals of the psychosocial evaluation include selection of candidates most likely to benefit from transplantation and identification of areas for psychosocial intervention, both before and after transplantation. The assessment should address the patient's premorbid psychiatric state, past adaptation to stressors, history of compliance with treatment, substance abuse history, and level of social support, including community and faith-based support systems. Results of psychometric assessments may be helpful when considered in conjunction with a clinical interview and other sources of information about the patient. It may also be helpful to use a screening tool developed specifically to evaluate psychosocial factors relevant to transplantation, such as the Psychological Assessment of Candidates for Transplantation (PACT) scale and the Transplantation Evaluation Rating Scale (TERS). The authors then review issues related to psychopharmacologic interventions in transplant patients, including the use of antidepressant medication pre- and post-transplant, strategies for avoiding delirium associated with immunosuppressive medications immediately post-transplantation, neuropsychiatric symptoms associated with interferon alpha therapy for hepatitis C, and interactions between over-the-counter and herbal agents (e.g., St. John's Wort) and immunosuppressive agents. Although limited research has been done on nonpharmacologic interventions, such as transplant support groups, it appears that certain types of group therapy, in particular, cognitive-behavioral groups that target specific risk factors such as depression, distress, and compliance, may also offer promising approaches for dealing with the problems of transplant patients. The authors then focus on two special situations that create particular problems for transplantation teams: liver transplantation in patients with alcoholic liver disease (ALD) and obesity in transplant patients. The authors conclude that the prognosis for patients with ALD who receive liver transplantation is similar to that of non-alcoholics and that alcoholism is not a contraindication for liver transplantation. However, careful preliminary psychosocial assessment is essential to review candidates for factors that are predictive of relapse, while close follow-up post-transplantation can help improve outcomes. It appears that obesity can increase the risk of negative outcomes in transplant patients, although there is currently no consensus on the use of obesity as an exclusion criteria. Interventions that take into account the special psychological and medical needs of transplant patients need to be developed for treating obesity both pre- and post-transplantation. Improved strategies for identifying high-risk patients and finding ways to intervene both pre- and post-transplantation can not only help lengthen transplant recipients' life spans, but also improve their adaptation to transplantation and lead to improved quality of life.

The Kit-activating mutation D816V enhances stem cell factor--dependent chemotaxis

The D816V mutation of c-kit has been detected in patients with mastocytosis. This mutation leads to constitutive tyrosine kinase activation of Kit. Because stem cell factor (SCF), the ligand for Kit (CD117(+)), is a chemoattractant for CD117(+) cells and one feature of mastocytosis is an abnormal collection of mast cells in tissues derived from CD34(+)CD117(+) mast cell precursors, the hypothesis was considered that the D816V mutation would enhance chemotaxis of these precursor cells. Constructs encoding wild-type Kit or Kit bearing the D816V mutation were transfected into Jurkat cells, labeled with Calcein-AM, and migration to SCF assessed in the presence or absence of tyrosine kinase inhibitors. Chemotaxis to SCF was enhanced in D816V transfectants compared to wild-type Kit transfectants (P <.002). Migration of both transfectants was inhibited by tyrosine kinase inhibitors, although D816V transfectants were more sensitive. Chemotaxis was next performed on CD34(+)CD117(+) circulating mast cell precursors obtained from patients with mastocytosis. Analysis of prechemotaxis and migrated cells showed that whereas less than 10% in the prechemotaxis sample had the D816V mutation, 40% to 80% of migrated cells had this mutation. These results demonstrate that the D816V Kit mutation enhances chemotaxis of CD117(+) cells, offering one explanation for increased mast cells observed in tissues of patients with mastocytosis. (Blood. 2001;98:1195-1199)

Lyn is required for normal stem cell factor-induced proliferation and chemotaxis of primary hematopoietic cells

Stem cell factor (SCF) binds to c-Kit and is an important mediator of survival, growth, and function of hematopoietic progenitor cells and mast cells. Lyn and other Src family members are activated by SCF and associate with phosphorylated tyrosine residues in the c-Kit juxtamembrane region. However, studies using c-Kit mutants incapable of directly recruiting Src family members suggest this kinase family plays a minimal role in c-Kit stimulus-response coupling mechanisms. The objective of this study was to specifically target Lyn and subsequently address its role in SCF-mediated responses of primary hematopoietic progenitor cells and mast cells. To this end, a dominant-inhibitory Lyn mutant and Lyn-deficient mice were used. Transfection of normal murine mast cells with kinase-inactive Lyn impaired SCF-induced growth. Further, SCF-induced proliferation and chemotaxis of Lyn-deficient mast cells were less than for wild-type mast cells. SCF-induced growth of progenitor cells lacking Lyn was also reduced compared with that of wild-type progenitor cells. Impairment of SCF-mediated responses of Lyn-deficient mast cells and progenitor cells did not result from reductions in surface expression of c-Kit. These studies demonstrate that Lyn is required for normal SCF-mediated responses of primary progenitors and for a differentiated lineage.

The stages of change for dietary fat and fruit and vegetable intake of patients at the outset of a cardiac rehabilitation program

PURPOSE

To determine the stages of change for dietary fat and fruit and vegetable intake of cardiac patients entering a rehabilitation program.

DESIGN

A cross-sectional study using a convenience sample of newly admitted cardiac rehabilitation patients.

SETTING

Department of Pulmonary and Cardiac Rehabilitation, Moses H. Cone Memorial Hospital, Greensboro, North Carolina.

SUBJECTS

Subjects (n = 226) were predominantly men, Caucasian, married, smokers with 9 to 12 years of education, and with primary diagnoses of coronary artery bypass graft.

MEASURES

Stages of change and food frequency questionnaires were completed by subjects upon admission to cardiac rehabilitation.

RESULTS

Subjects in action and maintenance stages for dietary fat reduction comprised 78.7% of the population. Subjects' percentage of energy from fat decreased linearly from the precontemplation stage (38.8%) to the maintenance stage (30.9%). Eighty-one percent of subjects were in precontemplation/contemplation for increasing fruit and vegetable intake. Daily servings of fruits and vegetables ranged from 2.6 for precontemplation to 5.1 for maintenance subjects. Age, body mass index (BMI), education, and family history for coronary disease were unrelated to stage of change for the dependent variables.

CONCLUSIONS

Patients were in different stages of change for two nutritional behaviors linked to the same disease. Results support the need to assess patients for food behaviors and apply different educational interventions for each food behavior.

Pathogenesis II: fungal responses to host responses: interaction of host cells with fungi

Most of our knowledge concerning the virulence determinants of pathogenic fungi comes from the infected host, mainly from animal models and more recently from in vitro studies with cell cultures. The fungi usually present intra- and/or extracellular host-parasite interfaces, with the parasitism phenomenon dependent on complementary surface molecules. Among living organisms, this has been characterized as a cohabitation event, where the fungus is able to recognize specific host tissues acting as an attractant, creating stable conditions for its survival. Several fungi pathogenic for humans and animals have evolved special strategies to deliver elements to their cellular targets that may be relevant to their pathogenicity. Most of these pathogens express surface factors that mediate binding to host cells either directly or indirectly, in the latter case binding to host adhesion components such as extracellular matrix (ECM) proteins, which act as 'interlinking' molecules. The entry of the pathogen into the host cell is initiated by fungal adherence to the cell surface, which generates an uptake signal that may induce its cytoplasmic internalization. Once this is accomplished, some fungi are able to alter the host cytoskeletal architecture, as manifested by a rearrangement of microtubule and microfilament proteins, and this can also induce epithelial host cells to become apoptotic. It is possible that fungal pathogens induce modulation of different host cell pathways in order to evade host defences and to foster their own proliferation. For a number of pathogens, the ability to bind ECM glycoproteins, the capability of internalization and the induction of apoptosis are considered important factors in virulence. Furthermore, specific recognition between fungal parasites and their host cell targets may be mediated by the interaction of carbohydrate-binding proteins, e.g., lectins on the surface of one type of cell, probably a parasite, that combine with complementary sugars on the surface of host-cell. These interactions supply precise models to study putative adhesins and receptor-containing molecules in the context of the fungus-host interface. The recognition of the host molecules by fungi such as Aspergillus fumigatus, Paracoccidioides brasiliensis and Histoplasma capsulatum, and their molecular mechanisms of adhesion and invasion, are reviewed in this paper.

Ethical Issues for Psychologists in Pain Management

Pain management is relatively young as a specialty. Although increasing attention is being paid to issues such as pain at the end of life and pain in underserved populations, only recently has an open discussion of ethical issues in chronic pain treatment come to the fore. Psychologists specializing in pain management are faced with a myriad of ethical issues. Although many of these problems are similar to those faced by general clinical psychologists or other health psychologists, they are often made more complex by the multidisciplinary nature of pain management and by the psychologists' relationships to third-party payers (health maintenance organizations, workers' compensation), attorneys, or other agencies. An open forum exploring ethical issues is needed. This article outlines major ethical considerations faced by pain management psychologists, including patient autonomy and informed consent, confidentiality, reimbursement and dual relationships, patient abandonment, assessment for medical procedures, clinical research, and the interface of psychology and medicine. American Psychological Association ethical principles and principles of biomedical ethics need to be considered in ethical decision making. Further exploration and discussion of ethics for pain management psychologists are recommended.

Mast cells in allergy and host defense

Mast cells have been implicated in the pathogenesis of allergic diseases and in inflammatory responses associated with pathological immune and disease-related processes including fibrosis, autoimmune pathology, and neoplasia. Recent findings in animal models of bacterial infection also suggest that mast cells may have a protective role in host defense against pathogens in innate immunity along with the probable role of mast cells in acquired immunity against parasitic infections. Mast cells are strategically located at the host-environment interface and may provide an early defense against an invading pathogen. Mast cells express an array of adhesion and immune receptors that may assist in the recognition of invading pathogens. When activated, these cells then synthesize and release key immunoregulatory cytokines, one consequence of which is to mobilize a rapid and vigorous inflammatory response. However, although it has been demonstrated that mast cells may have a role in innate immunity in defined in vitro and animal models, it remains to be determined whether mast cells are protective in innate immune responses in humans.