Predicting virulence of Aeromonas isolates based on changes in transcription of c-jun and c-fos in human tissue culture cells.

AIMS: To screen for the virulence potential of Aeromonas isolates based on the change in regulation of c-jun and c-fos in the human intestinal tissue culture cell line Caco-2. METHODS AND RESULTS: Aeromonas cells were added to Caco-2 cells at a ratio of approx. 1 : 1. After 1-, 2- and 3-h incubation at 37 degrees C, mRNA was extracted from the cells and gene expression of two host genes, c-jun and c-fos, quantified. Aeromonas isolates which were pathogenic in the neonatal mouse model demonstrated up-regulation of c-jun and c-fos compared to avirulent isolates. CONCLUSIONS: Human cell culture results showed that c-jun and c-fos were predictive of Aeromonas virulence. SIGNIFICANCE AND IMPACT OF THE STUDY: An Aeromonas relative virulence scale is proposed for use in the testing of Aeromonas drinking water isolates.

Assessing the effectiveness of low-pressure ultraviolet light for inactivating Mycobacterium avium complex (MAC) micro-organisms.

AIMS: To assess low-pressure ultraviolet light (LP-UV) inactivation kinetics of Mycobacterium avium complex (MAC) strains in a water matrix using collimated beam apparatus. METHODS AND RESULTS: Strains of M. avium (n = 3) and Mycobacterium intracellulare (n = 2) were exposed to LP-UV, and log(10) inactivation and inactivation kinetics were evaluated. All strains exhibited greater than 4 log(10) inactivation at fluences of less than 20 mJ cm(-2). Repair potential was evaluated using one M. avium strain. Light repair was evaluated by simultaneous exposure using visible and LP-UV irradiation. Dark repair was evaluated by incubating UV-exposed organisms in the dark for 4 h. The isolate did not exhibit light or dark repair activity. CONCLUSIONS: Results indicate that MAC organisms are readily inactivated at UV fluences typically used in drinking water treatment. Differences in activation kinetics were small but statistically significant between some tested isolates. SIGNIFICANCE AND IMPACT OF THE STUDY: Results provide LP-UV inactivation kinetics for isolates from the relatively resistant MAC. Although UV inactivation of Mycobacterium species have been reported previously, data collected in this effort are comparable with recent UV inactivation research efforts performed in a similar manner. Data were assessed using a rigorous statistical approach and were useful towards modelling efforts.

Consumer-run services research and implications for mental health care.

Mental health consumers/survivors developed consumer-run services (CRSs) as alternatives to disempowering professionally run services that limited participant self-determination. The objective of the CRS is to promote recovery outcomes, not to cure or prevent mental illness. Recovery outcomes pave the way to a satisfying life as defined by the individual consumer despite repetitive episodes of disorder. Recovery is a way of life, which through empowerment, hope, self-efficacy, minimisation of self-stigma, and improved social integration, may offer a path to functional improvement that may lead to a better way to manage distress and minimise the impact of illness episodes. 'Nothing about us without us' is the defining objective of the process activity that defines self-help. It is the giving of agency to participants. Without such process there is a real question as to whether an organisation is a legitimate CRS or simply a non-governmental organisation run by a person who claims lived experience. In considering the effectiveness of CRSs, fidelity should be defined by the extent to which the organisation's process conveys agency. Unidirectional helping often does for people what they can do for themselves, stealing agency. The consequence of the lack of fidelity in CRSs to the origins of the self-help movement has been a general finding in multisite studies of no or little difference in outcomes attributable to the consumer service. This, from the perspective of the research summarised herein, results in the mixing of programmatic efforts, some of which enhance outcomes as they are true mutual assistance programmes and some of which degrade outcomes as they are unidirectional, hierarchical, staff-directed helping efforts making false claims to providing agency. The later CRS interventions may provoke disappointment and additional failure. The indiscriminate combining of studies produces the average: no effect.

Modification of microneedles using inkjet printing.

In this study, biodegradable acid anhydride copolymer microneedles containing quantum dots were fabricated by means of visible light dynamic mask micro-stereolithography-micromolding and inkjet printing. Nanoindentation was performed to obtain the hardness and the Young's modulus of the biodegradable acid anhydride copolymer. Imaging of quantum dots within porcine skin was accomplished by means of multiphoton microscopy. Our results suggest that the combination of visible light dynamic mask micro-stereolithography-micromolding and inkjet printing enables fabrication of solid biodegradable microneedles with a wide range of geometries as well as a wide range of pharmacologic agent compositions.

Evaluating virulence of waterborne and clinical Aeromonas isolates using gene expression and mortality in neonatal mice followed by assessing cell culture's ability to predict virulence based on transcriptional response.

AIMS: To assess the virulence of Aeromonas spp. using two models, a neonatal mouse assay and a mouse intestinal cell culture. METHODS AND RESULTS: After artificial infection with a variety of Aeromonas spp., mRNA extracts from the two models were processed and hydridized to murine microarrays to determine host gene response. Definition of virulence was determined based on host mRNA production in murine neonatal intestinal tissue and mortality of infected animals. Infections of mouse intestinal cell cultures were then performed to determine whether this simpler model system's mRNA responses correlated to neonatal results and therefore be predictive of virulence of Aeromonas spp. Virulent aeromonads up-regulated transcripts in both models including multiple host defense gene products (chemokines, regulation of transcription and apoptosis and cell signalling). Avirulent species exhibited little or no host response in neonates. Mortality results correlated well with both bacterial dose and average fold change of up-regulated transcripts in the neonatal mice. CONCLUSIONS: Cell culture results were less discriminating but showed promise as potentially being able to be predictive of virulence. Jun oncogene up-regulation in murine cell culture is potentially predictive of Aeromonas virulence. SIGNIFICANCE AND IMPACT OF THE STUDY: Having the ability to determine virulence of waterborne pathogens quickly would potentially assist public health officials to rapidly assess exposure risks.

Increasing foraging opportunities for a group of captive capuchin monkeys (Cebus capucinus).

Capuchin monkeys often employ complex manipulative skills while recovering food items. Five captive Cebus capucinus were presented with two identical feeders that required the monkeys to lift up flaps, search through hay, and perform coordinated hand movements in order to obtain food items. The intent of this study was not to merely increase the amount of time the animals spent feeding, but to provide opportunities for greater expression of species-typical foraging behavior. In addition to their regular diet, figs and various types of unshelled nuts were placed inside the feeders. The monkeys avidly searched for and removed food from the feeders, displaying a wide variety of manipulative abilities. The amount of time the animals spent foraging significantly increased (p less than 0.05) whereas the amount of time the animals spent locomoting and resting significantly decreased (p less than 0.05) when the feeders were available. The feeders were portable, durable, easy to clean, and relatively inexpensive.

Transferrin synthesis by macrophages: up-regulation by gamma-interferon and effect on lymphocyte proliferation.

We have investigated transferrin synthesis by human and mouse lymphoid and myeloid cells. It was found that transferrin synthesis is a property of mouse but not human macrophages, whereas in man T lymphocytes synthesised transferrin. Synthesis by mouse macrophages showed a dose-dependent increase in response to gamma-interferon (gamma-IFN), but iron added as ferric nitrilotriacetate had no effect. Macrophage-derived transferrin was found to contain iron already bound to it and was able to support Con A-stimulated mouse lymphocyte proliferation.

Low pressure ultraviolet studies for inactivation of Giardia muris cysts.

AIMS: The research was initiated to confirm earlier ultraviolet (u.v.) light inactivation studies performed on Giardia cysts using excystation as the viability indicator. Following this, a comparison of in vitro excystation and animal infectivity was performed for assessing cyst viability after exposure to low-pressure u.v. irradiation. METHODS AND RESULTS: Cysts of Giardia muris were inactivated using a low-pressure u.v. light source. Giardia muris was employed as a surrogate for the human pathogen Giardia lamblia. Cyst viability was determined by both in vitro excystation and animal infectivity. Cyst doses were counted using a flow cytometer for the animal infectivity experiments. Using in vitro excystation as the viability indicator, fluences as high as approximately 200 mJ cm(-2) did not prevent some cysts from excysting, thus verifying earlier work. Using animal infectivity, u.v. fluences of 1.4, 1.9 and 2.3 mJ cm(-2) yielded log10 reductions ranging from 0.3 to >or= 4.4. CONCLUSIONS: Results indicate that in vitro excystation is not a reliable indicator of G. muris cyst viability after u.v. disinfection. Very low doses of u.v. light rendered G. muris cysts non-infective in the mouse model employed. SIGNIFICANCE AND IMPACT OF THE STUDY: Data presented represent the only complete u.v. inactivation curve for G. muris. This research provides evidence that u.v. can be an effective barrier against Giardia spp. in the treatment of drinking water supplies.

Ethanol and oral diazepam absorption.

Despite widespread use and abuse of ethanol and diazepam in combination, little is known about the effects of ethanol on diazepam absorption. We administered diazepam (0.07 mg per kilogram of body weight) with water and with 30 ml of 50 per cent ethanol to seven normal volunteers. Plasma diazepam levels were significantly higher at 60 minutes (P less than 0.05), 90 minutes (P less than 0.01), 120 minutes (P less than 0.01), and 240 minutes (P less than 0.01) when diazepam was administered with ethanol than with water alone. Since maximum mean plasma diazepam levels after combined ingestion with ethanol were nearly twice as high than after diazepam and water (373 ng per milliliter versus 197 ng per mililiter at 60 minutes) we conclude that ethanol enhanced diazepam absorption.

Cytokine-mediated regulation of transferrin synthesis in mouse macrophages and human T lymphocytes.

Transferrin (Tf) plays an important role during immunologic activation by donating iron to activated lymphocytes. Therefore, synthesis by lymphomyeloid cells has been investigated. Mouse macrophages and macrophage cell lines synthesized Tf, with levels being markedly increased by gamma-interferon (gamma-IFN) and, to a lesser extent, by interleukin-1 beta (IL-1 beta), IL-6, and tumor necrosis factor alpha (TNF alpha). Tf was also produced by phytohemagglutinin-stimulated human T cells and two T-cell lines and was increased by IL-2. Even after appropriate activation, none was synthesized by human macrophages or monocytic cell lines or by mouse T cells, T-cell lines, or thymus cells. In both species, B-lineage cell lines were negative. Tf was also synthesised by macrophages from congenitally hypotransferrinemic mice and was responsive to gamma-IFN, but levels were lower than those from normal controls. Synthesis by human and murine hepatoma cells was increased by IL-6 but unaffected by IL-1, TNF alpha, or gamma-IFN. Iron decreased synthesis by hepatoma cells but had no effect on the lymphomyeloid cells. Tf mRNA levels paralleled protein synthesis, suggesting that regulation was pre-translational. Thus, Tf synthesis by lymphomyeloid cells is regulated differently from hepatic synthesis, which is consistent with the suggestion that Tf may act in a paracrine (mouse) or autocrine (human) manner on activated lymphocytes.

Pharmacokinetics of sulbactam in humans.

Sulbactam, a new beta-lactamase inhibitor, has pharmacokinetic characteristics in humans similar to those of ampicillin and amoxicillin. Its half-life in humans is approximately 1 h. In a two-compartment pharmacokinetic model, the apparent volume of distribution for the central compartment is approximately 12 liters, and half of the dose is found in the central compartment in the postdistributive phase. Approximately 75% of a parenteral dose is excreted unchanged in urine. The coadministration of sulbactam with ampicillin, penicillin G, or cefoperazone has essentially no effect upon the kinetics of either the beta-lactam antibiotic or sulbactam.