Toxic effects of mebendazole at high dose on the haematology of red-legged pademelons (Thylogale stigmatica)

OBJECTIVE

To investigate the effects of mebendazole at high dose on the haematology of macropods. Experimental.

PROCEDURE

Five red-legged pademelons (Thylogale stigmatica) were dosed orally with mebendazole at 50 mg/kg/d for 5 to 6 days. Two control pademelons were dosed with water. Regular blood samples were taken for haematology over 20 days.

RESULTS

All four treated pademelons sampled at 5 days developed severe leucopenia and neutropenia, moderate lymphopenia, thrombocytopenia, eosinopenia and monocytopenia, as well as bone marrow aplasia within 5 to 11 days after the first mebendazole dose. Four pademelons died unexpectedly or became ill and were euthanased 5 to 11 days after the first dose while the other animal recovered after 5 days of illness. Necropsy revealed systemic infection with opportunistic enteric bacteria, non-suppurative inflammation in tissues, haemorrhage and ulceration of the gastrointestinal tract.

CONCLUSIONS

Red-legged pademelons rapidly develop bone-marrow aplasia and subsequent septicaemia after administration of high doses of mebendazole. Mebendazole at high doses should not be used for macropods.

Does home-based exercise improve body mass index in patients with type 2 diabetes? Results of a feasibility trial

AIMS

This feasibility trial evaluated the use, safety, and short-term benefits of a home-based exercise intervention designed to increase physical activity among adults with diabetes.

METHODS

Participants with type 2 diabetes in a group practice were recruited and randomly assigned to the home-based exercise intervention or usual care. Participants were given diabetes self-management education, instructed to exercise 30 min 5 days/week, and were followed for 3 months. The intervention contained three exercise routines (aerobic and resistance exercises). Outcomes included changes from baseline at 3 months between groups in body mass index (BMI), quality of life, A1C, and blood pressure.

RESULTS

Seventy-six sedentary adults completed the study: 49% intervention group, 68% women, 47% black, mean age 56.6+/-9.6 years. Using intention to treat analysis, a trend towards improvement between groups for BMI (mean change -0.4 versus 0.1, respectively; P=0.06) was identified. Thirty-eight percent of the intervention group adhered to 80% of the exercise recommendation and significantly improved BMI (-1.07; P<0.05). No other differences were detected between groups.

CONCLUSIONS

Home-based exercise interventions have potential to reduce BMI in patients with diabetes. The results provide variance estimates necessary to power a larger study of longer duration.

Investigation of the second wave (phase 2) of severe acute respiratory syndrome (SARS) in Toronto, Canada. What happened?

BACKGROUND

Severe acute respiratory syndrome (SARS) was introduced to Toronto on 23 February, 2003. The outbreak was believed to be over in early May after two incubation periods had passed with no newly identified cases. However, on 20 May, 2003 a cluster of respiratory illnesses occurred in a rehabilitation facility in Toronto. These cases were later identified as SARS but not until a community hospital in which one of these cases was previously hospitalized (Hospital X) had already experienced nosocomial transmission. This report describes the outbreak investigation of nosocomial transmission of SARS at Hospital X.

METHODS

An investigation of 90 probable and suspect cases of SARS associated with a hospital outbreak was performed. The investigation included death record reviews, chart reviews, case finding and contact tracing. Nursing cohorts who worked on the specific ward in which nosocomial transmission occurred had work-shift and patient-assignment records reviewed to determine source of infection.

RESULTS

The greatest number of cases occurred within hospital employees (42.5%) with an average age of 51 years and 69% being female. The mean incubation period for one time exposure patients was 6.3 days (range 4 to 10 days). Twelve (13.8%) of the cases died. Five of seven nurses who cared for a specific SARS patient during this period acquired SARS. Twelve of 17 (70.6%) nursing staff who developed SARS worked with another nursing staff who was symptomatic for SARS. Staff members who worked the evening shift or the morning shift and therefore likely attended a nursing appreciation breakfast were five times more likely to acquire SARS than those who did not attend.

INTERPRETATION

What was believed to be the end of the Toronto SARS outbreak led the Provincial Operations Centre (POC) to issue a directive allowing a more relaxed use of infection-control precautions during the beginning of Phase 2 of the outbreak. These relaxations of precautions were temporally associated with the nosocomial transmission of SARS to hospital staff, other patients and visitors at Hospital X. As a result of this outbreak significant changes have been made with respect to infection-control practices within Canada.

Evaluation of the immediate and midterm effects of mobilization in hot spa water on static and dynamic balance in elderly subjects

OBJECTIVES

The purpose of this study was to compare one and four weeks of active mobilization during balneotherapy (B) with mobilization on land (L) in terms of the respective effects on static and dynamic balance in elderly subjects.

METHODS

Twelve elderly volunteers (mean age: 65.6+/-6.3 years) were evaluated for pain (on a visual analogue scale, [VAS]), static balance (as measured by the centre of foot pressure, [COP]) and dynamic balance (the "Timed Up and Go" [TUG] test). Six measurement sessions were performed: three baseline sessions before exercise sessions (PostL, PreB1 and PreB4) and then after a land-based session L and after one and four weeks (B1 and B4) of balneotherapy at 34 degrees C (PostL, PostB1 and PostB4, respectively).

RESULTS

A Friedman analysis of variance (ANOVA) revealed significant differences between the six conditions in terms of the TUG and VAS results (p<0.01 and p<0.05, respectively). The TUG time decreased after the balneotherapy session(s) (p<0.01, PreB1 versus PostB1 and PreB4 versus PostB4). After sessions B1 and B4, a decrease in the VAS score was noted (p<0.05, PreB1 versus PostB1 and PreB4 versus PostB4). In contrast, there were no significant postbalneotherapy changes in any of the postural parameters.

CONCLUSION

Balneotherapy sessions appear to induce a decrease in pain and an increase in dynamic mobility. This might be explained by enhanced proprioceptive input during neuromuscular mobilization in water (i.e. with increased resistance but a lower load).

Additional disinfectants effective against the amphibian chytrid fungus Batrachochytrium dendrobatidis

Chytridiomycosis, a disease contributing to amphibian declines worldwide, is caused by the fungus Batrachochytrium dendrobatidis. Identifying efficient and practical disinfectants effective against B. dendrobatidis is important to reduce the spread of the disease both in the wild and captivity. Previous studies identified a range of suitable disinfectant strategies. We evaluated the suitability of 3 additional disinfectants: two of these (TriGene Virucidal Disinfectant Cleaner and F10 Super Concentrate Disinfectant) are mixtures of chemicals and one (Betadine Antiseptic Liquid) contains a single active ingredient, povidone iodine. The disinfectants were tested using a range of concentrations for 1,5 and 10 min to determine their ability to kill B. dendrobatidis in vitro. The measure of effectiveness was 100% kill of zoosporangia grown in multiwell plates. All disinfectants had a 100% efficacy at concentrations recommended by the manufacturers. The lowest concentrations capable of 100% kill after exposure for 1 min were 0.1 ml l(-1) for TriGene, 0.33 ml l(-1) for F10 and 100 ml l(-1) for Betadine. TriGene is the most effective disinfectant yet to be found, and both TriGene and F10 are more effective than various disinfectants tested in previous studies. TriGene and F10 are considered suitable for use in the field, as only small amounts of concentrate are needed.

Diagnostic assays and sampling protocols for the detection of Batrachochytrium dendrobatidis

Batrachochytrium dendrobatidis is a fungus belonging to the Phylum Chytridiomycota, Class Chytridiomycetes, Order Chytridiales, and is the highly infectious aetiological agent responsible for a potentially fatal disease, chytridiomycosis, which is currently decimating many of the world's amphibian populations. The fungus infects 2 amphibian orders (Anura and Caudata), 14 families and at least 200 species and is responsible for at least 1 species extinction. Whilst the origin of the agent and routes of transmission are being debated, it has been recognised that successful management of the disease will require effective sampling regimes and detection assays. We have developed a range of unique sampling protocols together with diagnostic assays for the detection of B. dendrobatidis in both living and deceased tadpoles and adults. Here, we formally present our data and discuss them in respect to assay sensitivity, specificity, repeatability and reproducibility. We suggest that compliance with the recommended protocols will avoid the generation of spurious results, thereby providing the international scientific and regulatory community with a set of validated procedures which will assist in the successful management of chytridiomycosis in the future.

Effets immédiats de séances de rééducation des membres inférieurs par balneotherapie sur le contrôle de l'équilibre

OBJECTIVE

The aim of this study was to compare the immediate effects of standard physiotherapy (S) and balneotherapy (B) on the postural capacity of subjects with lower-limb injuries.

METHODS

The postural sway of 12 voluntary subjects was evaluated before (REF1 and REF2) and after two different physiotherapy sessions performed in the swimming pool (B) or under (S). The centre of pressure (CP) trajectory was recorded by use of a force platform. CP displacements in the mediolateral and anteroposterior axes were then separated into two elementary superimposed components: the horizontal motion of the centre of gravity (CG) and the difference between the CP and the vertical projection of the CG (CP-CG). The amplitude of the latter component (CP-CG) is thought to express neuromuscular activity. All trajectories were then analysed in terms of classical and frequency parameters.

RESULTS

Postural sway did not differ before and after the physiotherapy sessions. Following both sessions, the mean CG velocity decreased significantly (P<0.5). The area of CP-CG trajectory was diminished solely by the aquatic exercise (P<0.5) and was associated with decreased amplitude of motion along the anteroposterior axis (P<0.05), which suggests decreased neuromuscular activity to maintain posture.

CONCLUSION

Interestingly, decreased motion was observed along the anteroposterior axis, which corresponds to ankle movements. Exercising lower-limb muscles under water could reinforce proprioceptive input, resulting in a better postural control.

Undisturbed upright stance control in the elderly: Part 2. Postural-control impairments of elderly fallers

A common way of predicting falling risks in elderly people can be to study center of pressure (CP) trajectories during undisturbed upright stance maintenance. By estimating the difference between CP and center of gravity (CG) motions (CP - CGv), one can estimate the neuromuscular activity. The results of this study, which included 34 sedentary elderly persons aged over 75 years (21 fallers and 13 nonfallers), demonstrated significantly increased CGh and CP - CGv motions in both axes for the fallers. In addition, the fallers presented larger CGh motions in the mediolateral axis, suggesting an enlarged loading-unloading mechanism, which could have reflected the adoption of a step-initiating strategy. As highlighted by fractional Brownian motion modeling, the distance covered by the CP - CGv motions before the successive control mechanisms switched was enhanced for the fallers in both axes, therefore increasing the risk that the CG would be outside of the base of support.

Undisturbed Upright Stance Control in the Elderly: Part 1. Age-Related Changes in Undisturbed Upright Stance Control

The authors investigated age-related changes in postural control in 33 healthy young adults (18-31 years), 29 seniors (62-75 years), and 22 elderly people (75-96 years). A force platform recorded the results. The horizontal motions of the center of gravity (CGh) and their difference in the plane of support CP - CGv were deduced from the complex center of pressure (CP) trajectories. With fractional Brownian modeling, one can establish that the aging process seems to induce a transition phase in which seniors take more time to initiate the corrective process in the mediolateral (ML) axis than do younger people. The elderly develop a new strategy characterized by the mobilization of higher neuromuscular energy to maintain equilibrium. In the ML axis, the larger displacements could be caused mainly by a hip strategy that could facilitate step initiation. In the anteroposterior (AP) axis, seniors and elderly individuals maintain a relative ability to stabilize their CG into the base of support compared with younger people.

Effects of dehydroepiandrosterone, Premarin and Acolbifene on histomorphology and sex steroid receptors in the rat vagina

To assess the specific estrogenic and/or androgenic effects of a potential novel hormone replacement therapy, we have examined the morphology of the rat vagina 9 months after ovariectomy (OVX) and treatment of OVX animals with dehydroepiandrosterone (DHEA), conjugated estrogens Premarin and the selective estrogen receptor modulator Acolbifene. OVX led to atrophy and inflammatory changes while Acolbifene reduced the inflammation incidence and induced mucification of the vaginal epithelium. Premarin induced a typical keratinized stratified squamous epithelium while DHEA induced stimulation of the vaginal epithelium, with mucous cells typical of an androgenic effect, combined with increased collagen fiber compactness of the lamina propria. On the other hand, after OVX, the vaginal muscle layer decreased by 46%, an effect which was 41 and 100% reversed by DHEA and Premarin, respectively. The present data show particularly interesting effects of DHEA on the three layers of the vaginal wall, namely a highly mucified epithelium, an increased muscularis thickness and increased collagen fiber compactness in the lamina propria. DHEA exerts both androgenic and estrogenic effects on the vaginal mucosa, thus providing a more physiological replacement therapy.

The Value of Suction Wound Drain after Carotid and Femoral Artery Surgery: A Randomised Trial Using Duplex Assessment of the Volume of Post-operative Haematoma

BACKGROUND

The use of vacuum suction drains after carotid endarterectomy (CEA) and groin dissection for arterial reconstruction surgery remains controversial. A large multicentre prospective randomised trial would be needed to show any difference if clinical end points (infection and haematoma) are used. Therefore, we conducted a study to evaluate the value of wound drainage using accurate duplex measurement of haematoma expecting a 25% difference in volume between drained and non-drained wounds.

PATIENTS AND METHODS

Seventy consecutive patients undergoing CEA and 73 patients who underwent 106 groins dissection were separately and blindly randomised into two groups: group (a) with wound drain and group (b) without wound drain. A duplex scan was carried out post-operatively to document the presence and volume of any wound haematoma.

RESULTS

The majority of wounds did not show any evidence of collections. 1. In the CEA patients duplex scan revealed wound haematoma in 8 patients with a median volume of 25 ml (5-65) in group (a) in comparison to 7 wound haematomas 31 ml (3-72) in group (b). Median suction drain drainage was 42 ml (10-120) when used. There was no significant difference between the two groups. Three patients 4.3% (two from the drain group) underwent evacuation of haematoma post-operatively.2. In the groin dissection patients most of the documented collections were trivial. Ultrasound scans showed 21 collections (20%), of these 7 (34%) were in group (a) and 14 (66%) were in group (b). There was no significant difference in wound collections between the two groups (p = 0.28). Only 5 collections (75%) exceeded 10 ml, three of them were in the drain group. One patient (1%), who did not have a drain, developed a wound collection, which needed re-exploration. When a drain was used the median drainage was 64.5 ml (range 10-220).

CONCLUSION

These results based on accurate measurement of wound collection suggest that there is no benefit in terms of reduction of the volume of haematoma on wound drainage after CEA or arterial reconstruction surgery involving the groin. A selective policy of use of drainage is therefore recommended.

RECALIBRATION OF SOMESTHETIC PLANTAR INFORMATION IN THE CONTROL OF UNDISTURBED UPRIGHT STANCE MAINTENANCE

To assess the effects of changes in somesthetic plantar information on upright quiet stance, a rotary plantar massage was applied under the feet of healthy subjects for ten minutes. The controlling variable, the centre of pressure (CP) displacements, were recorded, before and after massage, through a force platform and decomposed into two elementary motions: the vertical projection of the centre of gravity (CG(v)) and the difference between the latter and the CP (CP-CG(v)) along medio-lateral ML and antero-posterior AP directions. These motions were processed through frequency analysis and modelled as fractional Brownian motion. For CP-CG(v) motions, the frequency analysis shows that massage under the plantar soles induces a decrease of the amplitudes along the ML direction suggesting reduced overall muscular activity (abductor-adductor muscles of the hip according to Winter et al.). A general trend is that the CG(v) amplitudes are also diminished after massage especially in the ML direction, indicating a better distribution of the body weight on the two supports. On the other hand, the effects tend to vanish after about 8 minutes. Conversely, when the massage was given under the toes, no particular effect on any elementary motion was observed, suggesting that the plantar mechanoreceptors under the toes necessitate stronger stimulation to respond significantly and/or that the greater sensitivity obtained was not used by the CNS. Overall, this data emphasises the fact that a recalibration of somesthetic cues may occur when enhanced afferent information is fed to the postural system.

Modifying the gain of the visual feedback affects undisturbed upright stance control

OBJECTIVE

To assess the effects of visual feedback gain, which express the amplitudes of the displacements of the centre of pressure displayed on a computer screen.

DESIGN

The controlling variable, the centre of pressure trajectories, recorded using a force platform, were decomposed into two elementary motions: (1) the horizontal displacements of the centre of gravity and (2) the vertical projection of the difference between centre of pressure and the centre of gravity. These motions were processed through frequency analysis and modelled as fractional Brownian motion to assess their spatio-temporal linkage and their degree of control.

BACKGROUND

Although tests to modify the feedback gain have already been carried out, the specific effects from a biomechanical and motor control point of view need to be assessed.

METHODS

Thirteen healthy adults were tested through various visual feedback gains performed in random order.

RESULTS

By increasing the visual feedback gain, no difference is observed between centre of pressure and centre of gravity motions whereas a progressive diminution of centre of gravity horizontal motions is seen. This latter effect is principally explained by a reinforcement of control during corrective processes.

CONCLUSIONS

When the control of centre of gravity constitutes the main flaw in undisturbed stance maintenance, the efficiency of a visual feedback rehabilitation protocol should be largely improved by using an enhanced gain.

Effect of season and temperature on mortality in amphibians due to chytridiomycosis

OBJECTIVE

To investigate the distribution and incidence of chytridiomycosis in eastern Australian frogs and to examine the effects of temperature on this disease.

DESIGN

A pathological survey and a transmission experiment were conducted.

PROCEDURE

Diagnostic pathology examinations were performed on free-living and captive, ill and dead amphibians collected opportunistically from eastern Australia between October 1993 and December 2000. We conducted a transmission experiment in the laboratory to investigate the effects of temperature: eight great barred frogs (Mixophyes fasciolatus) exposed to zoospores of Batrachochytrium dendrobatidis and six unexposed frogs were housed individually in each of three rooms held at 17 degrees C, 23 degrees C and 27 degrees C.

RESULTS

Chytridiomycosis was the cause of death or morbidity for 133 (55.2%) of 241 free-living amphibians and for 66 (58.4%) of 113 captive amphibians. This disease occurred in 34 amphibian species, was widespread around the eastern seaboard of Australia and affected amphibians in a variety of habitats at high and low altitudes on or between the Great Dividing Range and the coast. The incidence of chytridiomycosis was higher in winter, with 53% of wild frogs from Queensland and New South Wales dying in July and August. Other diseases were much less common and were detected mostly in spring and summer. In experimental infections, lower temperatures enhanced the pathogenicity of B. dendrobatidis in M. fasciolatus. All 16 frogs exposed to B. dendrobatidis at 17 degrees C and 23 degrees C died, whereas 4 of 8 frogs exposed at 27 degrees C survived. However, the time until death for the frogs that died at 27 degrees C was shorter than at the lower temperatures. Infections in survivors were eliminated by 98 days.

CONCLUSION

Chytridiomycosis is a major cause of mortality in free-living and captive amphibians in Australia and mortality rate increases at lower temperatures.

A squamous cell carcinoma and an adenocarcinoma in Australian treefrogs

We describe the pathology in a captive adult White lipped treefrog (Litoria infrafrenata) with a squamous cell carcinoma of the skin and a free-living adult Common green treefrog (L. caerulea) with an adenocarcinoma of the skin. Although many amphibian neoplasms have been reported world wide, none had been described in Australian species.

Cryo-archiving of Batrachochytrium dendrobatidis and other chytridiomycetes

Batrachochytrium dendrobatidis is a major pathogen of frogs worldwide. It has been associated with catastrophic declines of frog populations including those in pristine habitats in Queensland, Australia. To facilitate genetic and disease studies of this fungus and related species, it is essential to have a reliable long-term storage method to maintain genetic integrity of isolates. We have adapted well-established techniques used for the long-term storage of tissue-culture cell lines to the preservation of B. dendrobatidis and other chytridiomycetes. This simple method has allowed us to recover these fungi from storage at -80 degrees C and in liquid nitrogen over an extended period. With this technique it is now possible to preserve saprobic and parasitic isolates from a variety of environmental and disease situations for comparative genetic and biological studies.

Prostate cancer susceptibility genes: lessons learned and challenges posed

In most developed countries, prostate cancer is the most frequently diagnosed malignancy in men. The extent to which the marked racial/ethnic difference in its incidence rate is attributable to screening methods, environmental, hormonal and/or genetic factors remains unknown. A positive family history is among the strongest epidemiological risk factors for prostate cancer. It is now well recognized that the role of candidate genetic markers to this multifactorial malignancy is more difficult to identify than the identification of other cancer susceptibility genes. Indeed, despite the localization of several susceptibility loci, there has been limited success in identifying high-risk susceptibility genes analogous to BRCA1 or BRCA2 for breast and ovarian cancer. Nonetheless, three strong candidate susceptibility genes have been described, namely ELAC2 (chromosome 17p11/HPC2 region), 2'-5'-oligoadenylate-dependent ribonuclease L (RNASEL), a gene in the HPC1 region, and Macrophage Scavenger Receptor 1 (MSR1), a gene within a region of linkage on chromosome 8p. Additional studies using larger cohorts are needed to fully evaluate the role of these susceptibility genes in prostate cancer risk. It is also of interest to mention that a significant percentage of men with early-onset prostate cancer harbor germline mutation in the BRCA2 gene thus confirming its role as a high-risk prostate cancer susceptibility gene. Although initial segregation analyses supported the hypothesis that a number of rare highly penetrant loci contribute to the Mendelian inheritance of prostate cancer, current experimental evidence better supports the hypothesis that some of the familial risks may be due to inheritance of multiple moderate-risk genetic variants. In this regard, it is not surprising that analyses of genes encoding key proteins involved in androgen biosynthesis and action led to the observation of a significant association between a susceptibility to prostate cancer and common genetic variants in some of those genes.