Emergence of Aspergillus fumigatus azole resistance in azole-naïve patients with chronic obstructive pulmonary disease and their homes.

Azole-resistant Aspergillus fumigatus (ARAF) has been reported in patients with chronic obstructive pulmonary disease (COPD) but has not been specifically assessed so far. Here, we evaluated ARAF prevalence in azole-naïve COPD patients and their homes, and assessed whether CYP51A mutations were similar in clinical and environmental reservoirs. Sixty respiratory samples from 41 COPD patients with acute exacerbation and environmental samples from 36 of these patient's homes were prospectively collected. A. fumigatus was detected in respiratory samples from 11 of 41 patients (27%) and in 15 of 36 domiciles (42%). Cyp51A sequencing and selection on itraconazole medium of clinical (n = 68) and environmental (n = 48) isolates yielded ARAF detection in 1 of 11 A. fumigatus colonized patients with COPD (9%) and 2 of 15 A. fumigatus-positive patient's homes (13%). The clinical isolate had no CYP51A mutation. Two environmental isolates from two patients harbored TR34 /L98H mutation, and one had an H285Y mutation. Coexistence of different cyp51A genotypes and/or azole resistance profiles was detected in 3 of 8 respiratory and 2 of 10 environmental samples with more than one isolate, confirming the need for a systematic screening of all clinically relevant isolates. The high prevalence of ARAF in patients with COPD and their homes supports the need for further studies to assess the prevalence of azole resistance in patients with Aspergillus diseases in Northern France.

[Physical activity and pulmonary rehabilitation in adults with asthma]. / Apports de l'activité physique et de la réadaptation respiratoire dans l'asthme de l'adulte.

Physical activity is reduced in people with asthma compared to the general population, especially in situations where patients have uncontrolled asthma symptoms, persistent airflow obstruction and other long-term medical problems, in particular obesity and anxiety. Exertional dyspnea, which is of multifactorial origin, is the main cause of reduced physical activity reduction and draws patients into a vicious circle further impairing quality of life and asthma control. Both the resumption of a regular physical activity, integrated into daily life, adapted to patients' needs and wishes as well as physical and environmental possibilities for mild to moderate asthmatics, and pulmonary rehabilitation (PR) for severe and/or uncontrolled asthmatics, improve control of asthma, dyspnea, exercise tolerance, quality of life, anxiety, depression and reduce exacerbations. A motivational interview to promote a regular programme of physical activity in mild to moderate asthma (steps 1 to 3) should be offered by all health professionals in the patient care pathway, within the more general framework of therapeutic education. The medical prescription of physical activities, listed in the Public Health Code for patients with long-term diseases, and pulmonary rehabilitation should be performed more often by specialists or the attending physician. Pulmonary rehabilitation addresses the needs of severe asthma patients (steps 4 and 5), and of any asthmatic patient with poorly controlled disease and/or requiring hospitalized for acute exacerbations, regardless of the level of airflow obstruction, and/or with associated comorbidities, and before prescribing biological therapies.

Aerodynamic damping during rapid flight maneuvers in the fruit fly Drosophila.

We systematically investigated the effect of body rotation on the aerodynamic torque generation on flapping wings during fast turning maneuvers (body saccades) in the fruit fly Drosophila. A quasi-steady aerodynamic simulation of turning maneuvers with symmetrically flapping wings showed that body rotation causes a substantial aerodynamic counter-torque, known as flapping counter-torque (FCT), which acts in the opposite direction to turning. Simulation results further indicate that FCTs are linearly dependent on the rotational velocity and the flapping frequency regardless of the kinematics of wing motion. We estimated the damping coefficients for the principal rotation axes - roll, pitch, yaw - in the stroke plane frame. FCT-induced passive damping exists about all the rotation axes examined, suggesting that the effects of body rotation cannot be ignored in the analysis of free-flight dynamics. Force measurements on a dynamically scaled robotic wing undergoing realistic saccade kinematics showed that although passive aerodynamic damping due to FCT can account for a large part of the deceleration during saccades, active yaw torque from asymmetric wing motion is required to terminate body rotation. In addition, we calculated the mean value of the damping coefficient at 21.00 x10(-12) N m s based on free-flight data of saccades, which is somewhat lower than that estimated by the simulation results (26.84 x 10(-12) N m s).

Point-of-care Hepatitis C virus testing and linkage to treatment in an Australian inner-city emergency department.

BACKGROUND: In Australia, Hepatitis C Virus (HCV) treatment is declining, despite broad access to direct-acting antiviral medication. People who inject drugs are proportionally over-represented in emergency department presentations. Emergency department assessment of people who have injected drugs for HCV presents an opportunity to engage this marginalised population with treatment. We describe the outcomes of risk-based screening and point-of-care anti-HCV testing for emergency department patients, and linkage to outpatient antiviral treatment. METHODS: During the three-month study period, consecutive adult patients who presented to the emergency department during the study times were screened for risk factors and offered the OraQuick oral HCV antibody test. Those with reactive results were offered venepuncture in the emergency department for confirmatory testing and direct-acting antiviral treatment in clinic. The main outcome measures were the number and proportion of viremic participants that were linked to the hepatitis clinic, commenced treatment and achieved a sustained viral response. Secondary outcome measures were the proportion (%) of presentations screened that were oral antibody reactive, and the prevalence and type of HCV risk factors. RESULTS: During the study period, 2408 of the 3931 (61%) presentations to the emergency department were eligible for screening. Of these 2408 patients, 1122 (47%) participated, 307 (13%) declined participation and 977 (41%) could not be approached during their time in the emergency department. Among the 1122 participants, 378 (34%) reported at least one risk factor. Subsequently, 368 (97%) of the 378 participants underwent OraQuick anti-HCV test, and 50 (14%) had a reactive result. A risk factor of ever having injected drugs was present in 44 (88%) of participants who were sero-positive. Of the 45 that had blood tested, 30 (67%) were HCV ribonucleic acid (RNA) positive. Three participants died. Of the 27 remaining participants, 10 (37%) commenced treatment and 7 of these 10 (70%) obtained a cure. There was a high rate of homelessness (24%) among anti-HCV positive participants. CONCLUSION: Among emergency department participants with a risk factor for HCV, positive serology was common using a rapid point-of-care test. A history of injecting drug use was identified as the risk factor with highest yield for positive HCV serology, and is suitable as a single screening question. However, linkage to care post ED presentation was low in this marginalised population. There is a need for new pathways to improve the care cascade for marginalised individuals living with HCV infection.

Effects of oxygen on exercise-induced increase of pulmonary arterial pressure in idiopathic pulmonary fibrosis.

INTRODUCTION: Idiopathic pulmonary fibrosis (IPF) is a severe disease with no known effective therapy. Patients with IPF may develop severe increase of pulmonary arterial pressure (PAP) on exercise, the mechanisms of which is not clearly identified. OBJECTIVES: To determine whether oxygen may correct the increase of PAP developed during exercise in patients with IPF. PATIENTS AND METHODS: We performed a prospective study on patients with IPF and no hypoxaemia at rest. The absence of pulmonary hypertension (PH) at rest was confirmed by echocardiography (systolic PAP <35 mmHg). Eight patients underwent echocardiography during exercise in air and with oxygen (to maintain saturation of at least 94%). Right ventricle-right atrium gradient and cardiac output were measured at rest, after each increment and at peak. We then compared the echocardiographic results obtained for air and oxygen. RESULTS: All patients developed significant increase of SPAP on exercise (73 +/- 14 mmHg in air). Oxygen did not significantly improve SPAP on exercise (SPAP: 76 +/- 15 mmHg). Echocardiographic characteristics were similar between air and oxygen except for exercise tolerance in term of workload (p=0.045) and endurance (p=0.017). Resting pulmonary function tests did not predict the occurrence of increase of PAP on exercise. CONCLUSION: Our results demonstrate that oxygen does not improve exercise-induced increase of PAP in patients with IPF and support the hypothesis that hypoxic vaso-constriction is not the main mechanism of acute increase of PAP during exercise.

Plant cell expansion. Unzipped by expansins.

Newly discovered plant proteins, known as expansins, break hydrogen bonds in the cell wall and may play an important role in plant growth.

Regulation of cardiac hypertrophy in vivo by the stress-activated protein kinases/c-Jun NH(2)-terminal kinases.

Cardiac hypertrophy often presages the development of heart failure. Numerous cytosolic signaling pathways have been implicated in the hypertrophic response in cardiomyocytes in culture, but their roles in the hypertrophic response to physiologically relevant stimuli in vivo is unclear. We previously reported that adenovirus-mediated gene transfer of SEK-1(KR), a dominant inhibitory mutant of the immediate upstream activator of the stress-activated protein kinases (SAPKs), abrogates the hypertrophic response of neonatal rat cardiomyocytes to endothelin-1 in culture. We now report that gene transfer of SEK-1(KR) to the adult rat heart blocks SAPK activation by pressure overload, demonstrating that the activity of cytosolic signaling pathways can be inhibited by gene transfer of loss-of-function mutants in vivo. Furthermore, gene transfer of SEK-1(KR) inhibited pressure overload-induced cardiac hypertrophy, as determined by echocardiography and several postmortem measures including left ventricular (LV) wall thickness, the ratio of LV weight to body weight, cardiomyocyte diameter, and inhibition of atrial natriuretic factor expression. Our data suggest that the SAPKs are critical regulators of cardiac hypertrophy in vivo, and therefore may serve as novel drug targets in the treatment of hypertrophy and heart failure.

Modulation of immune response in mice immunised with an inactivated Salmonella vaccine and gavaged with Andrographis paniculata extract or andrographolide.

Gavage of mice, immunised with an inactivated S. typhimurium vaccine, with Andrographis paniculata extract [APE] or andrographolide [AND] resulted in an enhancement of Salmonella-specific antibody response and induction of cell-mediated response against salmonellosis. Mice were vaccinated with either one or two doses of killed S. typhimurium vaccine and fed two different quantities of APE or AND, for 14 days in mice immunised with one dose of the vaccine, and for 28 days in mice immunised with two doses of vaccine, respectively. Both APE and AND were found to enhance IgG antibody levels against S. typhimurium, the enhancement being statistically significant in mice receiving two doses of the vaccine. Splenocyte cultures, prepared from mice immunised with the killed Salmonella vaccine and treated with APE or AND, showed a remarkable increase in the production IFN-gamma following stimulation with the bacterial lysate, indicating an induction of Salmonella-specific cell-mediated response/immune response.

Inhibition of ionizing radiation recovery processes in polyamine-depleted Chinese hamster cells.

Polyamines are involved in many cellular processes, including DNA structure and function. Since DNA, or some DNA-containing structure, is known to be the target for cell killing induced by ionizing radiation and a number of chemotherapeutic agents, we investigated the effects of polyamine depletion on cytotoxic responses of Chinese hamster cells to X-irradiation. Colony forming ability after single, acute radiation exposures of cells growing under oxic conditions was minimally affected by endogenous putrescine and spermidine depletion, achieved after treatment with alpha-difluoromethylornithine. Survival of cells rendered hypoxic and then irradiated was unaffected by alpha-difluoromethylornithine treatment. However, cellular recovery processes were nearly completely suppressed in polyamine-depleted cells, including sublethal damage recovery, as evidenced by split-dose irradiations in log phase cultures, and potentially lethal damage recovery, observed when growth-inhibited cultures were allowed time to repair radiation damage prior to being plated for colony formation. Both these recovery processes were restored by exogenous putrescine treatment. Reaccumulation of intracellular spermidine content closely correlated with restoration of potentially lethal damage recovery. Depletion of putrescine and spermidine pools had little effect on either single or double strand DNA break production or rejoining. These data demonstrate that both sublethal and potentially lethal damage recovery are polyamine-dependent processes in Chinese hamster cells, and imply that the mechanisms by which hamster cells recovery from these types of radiation damage are unrelated to their ability to rejoin DNA strand breaks, at least during the first hour after irradiation. Finally, these results suggest that the depletion of tumor polyamine content may be an effective method of enhancing the sensitivity of human tumors to fractionated radiotherapy.

Development of an agar-methyl cellulose clonogenic assay for cells in transitional cell carcinoma of the human bladder.

We report the development of a clonogenic assay for progenitor cells in transitional cell carcinoma of the bladder. Colony growth has been demonstrated from cells obtained both from surgical biopsies and from bladder barbotages. Electron microscopic and karyotypic evidence supports the contention that these progenitors represent a part of the population maintaining the tumor in vivo. Colony growth occurred in 9 of 11 surgical biopsy samples and in 6 of 6 bladder barbotage samples. Plating efficiency ranged up to 0.7%, and colony size was in some instances greater than 1000 cells. The assay appears potentially useful for analysis of the biology of human transitional cell carcinoma.

Xyloglucan Endotransglycosylase Activity in Carrot Cell Suspensions during cell Elongation and Somatic Embryogenesis.

Xyloglucan endotransglycosylase (XET) has been proposed to contribute to cell elongation through wall loosening. To explore this relationship further, we assayed this enzyme activity in suspensions of carrot (Daucus carota L.) cells exhibiting various rates of cell elongation. In one cell line, elongation was induced by dilution into dichlorophenoxyacetic acid (2,4-D)-free medium. During this elongation, 93% of the XET activity was found in the culture medium; in nonelongating controls, by contrast, 68% was found in the cell extracts even though the specific activity of these extracts was lower than in the elongating cells. By far the highest rates of XET secretion per cell were in the elongating cells. A second cell line was induced to undergo somatic embryogenesis by dilution into 2,4-D-free medium. During the first 6 d, numerous globular embryoids composed of small, isodiametric cells were formed in the absence of cell elongation; extracellular XET activity was almost undetectable, and intracellular specific activity markedly declined. After 6 d, heart, torpedo, and cotyledonary embryoids began to appear (i.e. cell elongation resumed); the intracellular specific activity of XET rose rapidly and >80% of the XET activity accumulated in the medium. Thus, nonexpanding cell suspensions (whether or not they were rapidly dividing) produced and secreted less XET activity than did expanding cells. We propose that a XET molecule has an ephemeral wall-loosening role while it passes through the load-bearing layer of the wall on its way from the protoplast into the culture medium.

Xyloglucan Endotransglycosylase Activity Increases during Kiwifruit (Actinidia deliciosa) Ripening (Implications for Fruit Softening).

The activity of xyloglucan endotransglycosylase (XET) was as-sayed in three tissue zones of kiwifruit (Actinidia deliciosa [A. Chev.] C.F. Liang et A.R. Ferguson var deliciosa cv Hayward) at harvest and at several softening stages following a postharvest ethylene treatment. At harvest, extractable XET activity per unit fresh weight in the inner pericarp (IP) and core tissue was 4.5 and 42 times higher, respectively, than in the outer pericarp (OP). Within 24 h of ethylene treatment there was an increase in the activity and specific activity of XET in all tissues that continued throughout softening. Activity increased most in the OP, where it showed a 12-fold rise 6 d after ethylene treatment compared with 4.5- and 2.5-fold increases in the IP and core tissues, respectively. Visible swelling of the cell wall in each tissue was observed 24 h after the first detectable rise in XET activity and was most pronounced in the OP, which showed the greatest percentage increase in XET activity. Xyloglucan, galactoglucomannan, and cell wall materials isolated and purified from kiwifruit OP were tested as donor substrates for kiwifruit XET. The enzyme showed activity against xyloglucan but was inactive against galactoglucomannan. XET was active against cell wall materials from unripe and ripe fruit, with swollen walls from the latter being the better substrate. The results indicate that XET may have a key role early in fruit ripening, loosening the cell wall in preparation for further modification by other cell wall-associated enzymes.

Formation of Di-Isodityrosine and Loss of Isodityrosine in the Cell Walls of Tomato Cell-Suspension Cultures Treated with Fungal Elicitors or H2O2.

About 84% of the hydroxyproline residues in a cell culture of tomato (Lycopersicon esculentum x Lycopersicon peruvianum) were present in phenol-inextractable (i.e. covalently wall-bound) material. Treatment of the cells with any of three fungal elicitors (wall fragments from Phytophthora megasperma and Pythium aphanidermatum and xylanase from Aureobasidium pullulans) or with 1 mM H2O2 had little effect on the quantity of phenolinextractable hydroxyproline per milligram of freeze-dried cells. However, each treatment induced a decrease in the content of phenol-inextractable isodityrosine (Idt) residues. Each treatment, except with the P. megasperma fragments, also induced an increase in phenol-inextractable di- (Di-Idt). The increase in Di-Idt partly accounted for the loss of Idt. We conclude that the elicitors and H2O2 acted to reinforce the existing cross-linking of cell wall (glyco)proteins by evoking oxidative coupling reactions to convert Idt to Di-Idt plus unidentified products. The promotion of cross-linking by elicitor treatment is proposed to be a defensive response that restricts the penetration of pathogens.

Root Growth Maintenance at Low Water Potentials (Increased Activity of Xyloglucan Endotransglycosylase and Its Possible Regulation by Abscisic Acid).

Previous work suggested that an increase in cell wall-loosening contributes to the maintenance of maize (Zea mays L.) primary root elongation at low water potentials ([psi]w). It was also shown that root elongation at low [psi]w requires increased levels of abscisic acid (ABA). In this study we investigated the effects of low [psi]w and ABA status on xyloglucan endotransglycosylase (XET) activity in the root elongation zone. XET is believed to contribute to wall-loosening by reversibly cleaving xyloglucan molecules that tether cellulose microfibrils. The activity of XET per unit fresh weight in the apical 10 mm (encompassing the elongation zone) was constant at high [psi]w but increased by more than 2-fold at a [psi]w of -1.6 MPa. Treatment with fluridone to decrease ABA accumulation greatly delayed the increase in activity at low [psi]w. This effect was largely overcome when internal ABA levels were restored by exogenous application. Spatial distribution studies showed that XET activity was increased in the apical 6 mm at low [psi]w whether expressed per unit fresh weight, total soluble protein, or cell wall dry weight, corresponding to the region of continued elongation. Treatment with fluridone progressively inhibited the increase in activity with distance from the apex, correlating with the pattern of inhibition of elongation. Added ABA partly restored activity at all positions. The increase in XET activity at low [psi]w was due to maintenance of the rate of deposition of activity despite decreased deposition of wall material. The loss of activity associated with decreased ABA was due to inhibition of the deposition of activity. The results demonstrate that increased XET activity is associated with maintenance of root elongation at low [psi]w and that this response requires increased ABA.

Oligosaccharins as plant growth regulators.

Oligosaccharides with regulatory effects on living plant tissue have been obtained by parital hydrolysis of xyloglucan, cellulose and pectic polysaccharides. Attention is focused here on xyloglucan-derived oligosaccharides (XGOs), which exert the following two distinct effects on cell growth in pea-stem segments. (i) At approx. 1 nM, the L-fucosylated XGOs, such as XXFG, XFFG and FG (for structure of XXFG, see Fig. 1), antagonize 2,4-dichlorophenoxyacetic acid (2,4-D)-stimulated growth. At approx. 100 nM, XXFG loses this growth-inhibitory effect, probably because it gains a growth-promoting effect [see (ii)]; in contrast, FG retains its growth-inhibitory effect. The growth-inhibitory effect is tentatively attributed to membrane-binding of the active XGOs. (ii) At approx. 1 microM, at least four different cellotetraose-based XGOs (XXXG, XXLG, XXFG and XLLG) mimic auxin in that they induce growth. This effect is thus not L-fucose-dependent and is not exhibited by the cellobiose-based pentasaccharide, FG. Effect (ii) is attributed to the ability of cellotetraose-based XGOs to act as acceptor substrates for xyloglucan endotransglycosylase. [formula: see text] The biosynthesis and biodegradation of relevant XGOs has been investigated. By use of labelling with L-[3H]arabinose and L-[3H]fucose in vivo, XXFG and O-acetyl derivatives thereof were shown to accumulate extracellularly, in spinach cell cultures, to approx. 0.1 microM. The kinetics of labelling of XXFG showed it to be formed by degradation of pre-formed polysaccharide rather than by de novo synthesis of the oligosaccharide. XXFG was remarkably stable in vivo, undergoing little hydrolysis in contact with the surfaces of cultured cells; the major metabolic fate of exogenous [3H]XXFG was sequestration into apoplastic polysaccharide by endotransglycosylation.

Studies of U.S. radium dial workers: an epidemiological classic.

The tragic history of the exposure during the second and third decades of this century in the United States of radium dial workers, patients and members of the public to ionizing radiation from internally deposited isotopes of radium is well documented. Recognition of abnormal health outcomes among female dial workers and determination of a causal association between these outcomes among the workers and their exposure to radium leading to the development of protection standards is a classic example of an epidemiological process whereby knowledge and understanding of "the distribution and determinants of disease" evolve. Health effects studies involving U.S. female dial workers began in the early 1920s and continued into the present decade. These studies are discussed in the context of the epidemiological process whereby cause-effect relationships may be postulated, evaluated and refined to the benefit of workers and the general public.

Analyses of combined mortality data on workers at the Hanford Site, Oak Ridge National Laboratory, and Rocky Flats Nuclear Weapons Plant.

An important objective of studies of workers exposed occupationally to chronic low doses of ionizing radiation is to provide a direct assessment of health risks resulting from this exposure. This objective is most effectively accomplished by conducting combined analyses that allow evaluation of the totality of evidence from all study populations. In this paper, combined analyses of mortality in workers at the Hanford Site, Oak Ridge National Laboratory, and Rocky Flats Nuclear Weapons Plant are presented. These combined analyses provide no evidence of a correlation between radiation exposure and mortality from all cancer or from leukemia. Of 11 other specific types of cancer analyzed, multiple myeloma was the only cancer found to exhibit a statistically significant correlation with radiation exposure. Estimates of the excess risk of all cancer and of leukemia, based on the combined data, were negative. Upper confidence limits based on the combined data were lower than for any single population, and were similar to estimates obtained from recent analyses of A-bomb survivor data. These results strengthen support for the conclusion that estimates obtained through extrapolation from high-dose data do not seriously underestimate risks of low-dose exposure, but leave open the possibility that extrapolation may overestimate risks.

Tracking of flying insects using pan-tilt cameras.

Potent and affordable video and computer systems for automatic data acquisition are becoming increasingly important in behavioural neuroscience. It has remained challenging, however, to acquire data from small and fast-moving animals, such as insects in flight, due to the limited spatial and temporal resolution of the systems currently available. Our research on free-flying insects motivated the development of new methods in the context of two different experimental settings. First, the position and precise body axis direction of honey bees approaching a food source were automatically measured. Second, the flight trajectories of a phonotactic parasitoid fly homing in on its cricket host were recorded in 3D. We used pan-tilt cameras, i.e. cameras with moveable optics, to follow the animal's path with a close up image. Novel methods were developed for image acquisition and position measurement using pan-tilt cameras, as well as calibration and data evaluation in 3D world coordinates. The innovations of this system comprise: (1) Acquisition of images in high spatial detail over large observation areas. (2) Image acquisition at a field rate of 50 Hz PAL. (3) Free positioning of the cameras for 3D acquisition. (4) Computation of the flight path in 3D world coordinates. We illustrate the capabilities of the system with data obtained from a calibration object as well as from the behaviour of unrestricted, free-flying flies and bees. Potential applications in behavioural neuroscience and the psychophysics of sensory perception are briefly discussed.

Context-dependent stimulus presentation to freely moving animals in 3D.

The presentation of controllable, dynamic sensory stimuli provides a powerful experimental paradigm, which has been extensively applied to explore sensory processing in walking and tethered flying insects. Recent advances in computer hardware and software technology provide the opportunity to track the 3D flight path of free-flying insects and process these data in real-time, opening up the possibility to present dynamic stimuli to free-flying animals. To accommodate for the increased complexity relating to 3D space, we partitioned experimental design, real-time data acquisition and stimulus control into multiple self-contained modules. 3D experimental scenarios were created in a stand-alone application by forging multiple 3D space-stimulus relationships. The use of dynamic cues is illustrated by an experiment, in which dynamic acoustic cues were presented to a free-flying parasitoid fly in a large 3D environment. The combination of loosely coupled modules provides robust and flexible solutions, allowing new paradigms to be readily implemented based on existing technologies. We demonstrate this with a test system that displayed a complex visual stimulus, controlled in real-time by the 2D position and orientation of a test object. The presented methods are applicable in a variety of novel experimental paradigms, including learning paradigms, for various sensory modalities in walking, swimming and flying animals.

The echocardiographic diagnosis, characterization, and extraction guidance of cardiac foreign bodies.

Echocardiography is ideal for localizing cardiac foreign bodies and for characterizing associated cardiac and vascular injury before and during extraction. We report 5 cases of traumatic and iatrogenic cardiac foreign bodies that illustrate the central role of transthoracic and transesophageal ultrasonography in the management of these patients.