Assay interference leading to erroneous pregnancy-associated plasma protein-A results

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The sensory and affective components of pain: are they differentially modifiable dimensions or inseparable aspects of a unitary experience? A systematic review

BACKGROUND

Pain is recognised to have both a sensory dimension (intensity) and an affective dimension (unpleasantness). Pain feels like a single unpleasant bodily experience, but investigations of human pain have long considered these two dimensions of pain to be separable and differentially modifiable. The evidence underpinning this separability and differential modifiability is seldom presented. We aimed to fill this gap by evaluating the current evidence base for whether or not the sensory and affective dimensions of pain can be selectively modulated using cognitive manipulations.

METHODS

A rigorous systematic search, based on a priori search terms and consultation with field experts, yielded 4270 articles. A detailed screening process was based on the following recommendations: (i) evaluation of effectiveness; (ii) examination of methodological rigour, including each study having an a priori intention to cognitively modulate one of the two dimensions of pain; and (iii) sound theoretical reasoning. These were used to ensure that included studies definitively answered the research question.

RESULTS

After in-depth critique of all 12 articles that met the inclusion criteria, we found that there is no compelling evidence that the sensory and affective dimensions of pain can be selectively and intentionally modulated using cognitive manipulations in humans.

CONCLUSIONS

We offer potential explanations for this discrepancy between assumptions and evidence and contend that this finding highlights several important questions for the field, from both the research and clinical perspectives.

Pharmacokinetics and ex vivo anti-inflammatory effects of oral misoprostol in horses

BACKGROUND

Misoprostol is an E prostanoid (EP) 2, 3 and 4 receptor agonist that is anecdotally used to treat and prevent NSAID-induced GI injury in horses. Misoprostol elicits anti-inflammatory effects in vivo in men and rodents, and inhibits TNFα production in equine leucocytes in vitro.

OBJECTIVE

Define the pharmacokinetic parameters of oral misoprostol in horses, and determine the inhibitory effect of oral misoprostol administration on equine leucocyte TNFα production in an ex vivo inflammation model.

STUDY DESIGN

Pharmacokinetic study, ex vivo experimental study.

METHODS

Six healthy adult horses of mixed breeds were used. In phase one, horses were given 5 μg/kg misoprostol orally, and blood was collected at predetermined times for determination of misoprostol free acid (MFA) by UHPLC-MS/MS. Pharmacokinetic parameters were calculated. In phase two, horses were dosed as in phase one, and blood was collected at T0, 0.5, 1 and 4 h following misoprostol administration for leucocyte isolation. Leucocytes were stimulated with 100 ng/mL LPS, and TNFα mRNA concentrations were determined via quantitative real-time PCR.

RESULTS

About 5 μg/kg oral misoprostol produced a rapid time to maximum concentration (Tmax ) of 23.4 ± 2.4 min, with a maximum concentration (Cmax ) of 0.29 ± 0.07 ng/mL and area under the curve (AUC0-∞ ) of 0.4 ± 0.12 h ng/mL. LPS stimulation of equine leucocytes ex vivo significantly increased TNFα mRNA concentrations, and there was no significant effect of misoprostol even at the Tmax .

MAIN LIMITATIONS

Only a single dose was used, and sample size was small.

CONCLUSIONS

Misoprostol is rapidly absorbed following oral administration in horses, and a single 5 μg/kg dose had no significant inhibitory effect on ex vivo LPS-stimulated TNFα mRNA production in leucocytes. Further studies analysing different dosing strategies, including repeat administration or combination with other anti-inflammatory drugs, are warranted.

Microcarrier Enhanced Survival of Human and Rat Fetal Ventral Mesencephalon Cells Implanted in the Rat Striatum

The transplantation of tissue containing dopamine-producing cells into the mammalian central nervous system is an emerging treatment for Parkinson's disease, despite relatively poor survival of implanted tissue. Recent evidence has suggested that Cytodex microcarriers enhance the survival of dopaminergic rat chromaffin cells transplanted into the rat striatum in the absence of immunosuppression. The current study was undertaken to evaluate the survival of rat and human fetal ventral mesencephalic neurons (VM) implanted alone or after attachment to microcarriers in the striatum of rats without immunosuppression. Rat fetal VM neurons demonstrated enhanced survival in the rat striatum when transplanted on microcarriers, compared to their transplantation alone during the 3-mo period examined in the present study. Transplants of human fetal VM neurons on microcarriers also survived remarkably well in the rat striatum without systemic immunosuppression. In contrast, human fetal VM cells transplanted alone into the rat striatum did not survive without systemic immunosuppression. There was no evidence of TH fiber sprouting in the vicinity of any transplant site. These data indicated that Cytodex microcarriers provide enhanced survival of both rat allograft and human xenograft fetal mesencephalic cells in the rat striatum without the necessity of systemic immunosuppression, perhaps by inducing a unique neuron–glia environment.

Characteristics and expectations of fluid bolus therapy: a bi-national survey of acute care physicians

There is little consensus on the definition or optimal constituents of fluid bolus therapy (FBT), and there is uncertainty regarding its physiological effects. The aims of this study were to determine clinician-reported definitions of FBT and to explore the physiological responses clinicians expect from such FBT. In June and October 2014, intensive care and emergency physicians in Australia and New Zealand were asked to participate in an electronic questionnaire of the reported practice and expectations of FBT. Two hundred and fifty-one questionnaires were completed, 65.3% from intensivists. We identified the prototypical FBT given by intensivists is more than 250 ml of compound sodium lactate, saline or 4% albumin given in less than 30 minutes, while that given by emergency department physicians is a similar volume of saline delivered over a similar time frame. Intensive care and emergency physicians expected significantly different changes in mean arterial pressure (P=0.001) and heart rate (P=0.033) following FBT. Substantial variation was demonstrated in the magnitude of expected response within both specialties for each variable. Major variations exist in self-reported FBT practice, both within and between acute specialties, and wide variation can be demonstrated in the expected physiological responses to FBT. International explorations of practice and prospective quantification of the actual physiological response to FBT are warranted.

RU486 facilitates or disrupts the sensitization of sexual behaviors by estradiol in the ovariectomized Long-Evans rat: Effect of timecourse

An acute injection of estradiol benzoate (EB) to the ovariectomized (OVX) rat activates low levels of lordosis, and subsequent progesterone (P) administration augments lordosis and recruits a complete pattern of sexual behavior including appetitive behaviors (e.g., hops/darts and solicitations). However, repeated injections of 5μg or 10μg EB (but not 2μg EB), administered every 4days to sexually-experienced OVX rats results in a behavioral sensitization, such that lordosis quotients (LQs) and appetitive behaviors progressively increase. We have shown that adrenal P does not play a critical role because behavioral sensitization to EB is not prevented by adrenalectomy. Here we tested whether P receptors play a role by examining the effect of chronic administration of the P receptor antagonist RU486 at a dose that reliably inhibits sexual behavior in fully primed OVX rats. Females were treated with EB (5 or 10μg), and 5mg RU486 dissolved in 0.4mL vehicle (VEH; 80% sesame oil, 15% benzyl benzoate, 5% benzyl alcohol) 48h and 5h prior to each of 7 tests, respectively, occurring at 4-day intervals in unilevel 4-hole pacing chambers. Control animals were treated with 2, 5, or 10μg EB+VEH. As expected, sensitization did not occur in females treated with 2μg EB+VEH, and those females received fewer intromissions and ejaculations than all other groups. RU486 did not prevent the sensitization of LQ, moderate and high lordosis magnitudes (LM2 and LM3) or appetitive sexual behaviors on early tests, and in fact potentiated appetitive behaviors, LQ, LM2 and LM3, consistent with its facilitative actions in females treated with EB-alone, as we and others have reported previously. However, despite the initial facilitation, blocking P receptors by chronic administration of RU486 inhibited the maintenance of behavioral sensitization to EB.

Behavioral defeminization by prenatal androgen treatment in rats can be overcome by sexual experience in adulthood

Exposure to testosterone during a critical period of prenatal development disrupts the normal display of sexual behaviors in adult ovariectomized (OVX) rats treated with estradiol benzoate (EB) followed by progesterone (P). The organizational hypothesis posits that prenatally androgenized females (PNAFs) are desensitized to EB. We tested this hypothesis by first treating PNAFs with varying doses of EB (2.5, 5, 10, 20μg) followed by P (500μg), and second by subjecting females to an established EB behavioral sensitization paradigm where females are first given sexual experience with EB (10μg) and P prior to repeated sexual behavior testing with EB alone. Long-Evans females were androgenized in utero by a s.c. injection of 500μg testosterone propionate or the oil control to pregnant dams on gestational day 18. Female offspring were OVX on postnatal day 80 and tested one week later in the unilevel 4-hole pacing chamber. Genital tissue was defeminized in PNAFs, and the lordosis quotient (LQ) and partial (i.e., hops/darts) and full solicitations were significantly lower, while defensive behaviors were higher, in PNAF females, relative to non-PNAF females regardless of the acute EB priming dose. However, repeated testing with EB alone (10μg), or EB and P eliminated the differences between groups on LQ and hops/darts, indicating that the behavioral deficit can be overcome by sexual experience. These results suggest that PNAFs are not desensitized to EB, and despite disruptions in sexual differentiation of anatomical structures, the deficiency in sexual behavior in response to acute EB and P can be experientially overcome. PNAFs appear, however, to have a chronic deficit in the expression of full solicitations.

Death, taxes and advance directives

Suboptimal care at the end-of-life can be due to lack of access or knowledge of patient wishes. Ambiguity is often the result of non-standardized formats. Borrowing digital technology from other industries and using existing health information infrastructure can greatly improve the completion, storage, and distribution of advance directives. We believe several simple, low-cost adaptations to regional and federal programs can raise the standard of end-of-life care.

Use of ultrasound to evaluate outcome following colic surgery for equine large colon volvulus

REASONS FOR PERFORMING STUDY

The post operative response of the large colon wall after a surgically corrected large colon volvulus (LCV) has not been investigated.

OBJECTIVES

To use transabdominal ultrasound to monitor the post operative change in large colon wall thickness following surgical correction of LCV.

HYPOTHESIS

A prolonged period to colon wall involution is correlated with an increased rate of post operative morbidity and mortality.

METHODS

A prospective clinical study including horses that presented to the North Carolina State University Veterinary Teaching Hospital for colic between September 2006 and March, 2008, had surgically diagnosed and corrected LCV (at least 360 degrees ) without resection and recovered from anaesthesia. Ultrasound of the ventral large colon was performed at the time of anaesthetic recovery and every 6-8 h until the colon wall returned to normal thickness (< or = 5 mm). Outcome was evaluated using a one-way ANOVA to compare average time to colon wall involution between: 1) survivors and nonsurvivors; and 2) horses that developed multiple organ dysfunction syndrome (MODS) during the post operative period and those that recovered without evidence of MODS.

RESULTS

Sixteen horses that recovered without evidence of MODS had a significantly shorter period to colon wall involution (< or = 5 mm) compared to those diagnosed with MODS (mean +/- s.e. 19.6 h +/- 2.5 and 39.7 h +/- 6.7 respectively, P = 0.006). There was no significant difference in mean period to colon wall involution between survivors and nonsurvivors (26.2 +/- 4.9 and 33.2 +/- 7.8 h, respectively).

CONCLUSIONS

A shorter time to colon wall involution was associated with decreased post operative morbidity in horses presented for surgical correction of large colon volvulus without resection.

POTENTIAL RELEVANCE

Ultrasonographic monitoring of colon wall involution after surgical correction of LCV may aid in identifying those cases at risk of MODS. Further investigation of colon wall involution time using a larger number of horses is warranted.

Human cytomegalovirus (CMV)-specific CD8+ T cell responses are reduced in HIV-infected individuals with a history of CMV disease despite CD4+ T cell recovery

Cytomegalovirus (CMV)-specific immunity was investigated in human immunodeficiency virus (HIV)-infected individuals. A case-control (1:2) study was performed with cases defined as having a history of CMV end-organ disease (n=15) and controls (n=30) matched by current CD4(+) T cell count. CMV-specific CD8(+) T cells responses were quantified using the high throughput Quantiferon-CMV test (Cellestis, Melbourne, Australia). 40/44 (91%) had a positive Quantiferon-CMV test and the magnitude of response to CMV peptides correlated significantly with response to mitogen (p<0.0001) but not with CD4(+) T cell count at the time of testing, CD4(+) T cell nadir or HIV viral load. Cases had a significantly lower Quantiferon-CMV test than controls but there was no significant difference in response to mitogen or other antigens. In individuals with a history of CMV disease, CMV-specific CD8(+) T cell responses are reduced even in the setting of CD4(+) T cell reconstitution.

A long-term bacteriological and immunological study in Holstein-Friesian cattle experimentally infected with Mycobacterium avium subsp. paratuberculosis and necropsy culture results for Holstein-Friesian cattle, Merino sheep and Angora goats

The aims were to longitudinally evaluate the interferon-gamma (IFN-gamma) test in comparison to faecal culture and the absorbed ELISA in a cattle infection model for Johne's disease and to determine the adult infection status, by necropsy and tissue culture, of sheep, goats and cattle infected as young animals. Clinical disease, faecal culture results and immunological responses for Merino sheep [Stewart, D.J., Vaughan, J.A., Stiles, P.L., Noske, P.J., Tizard, M.L.V., Prowse, S.J., Michalski, W.P., Butler, K.L., Jones, S.L., 2004. A long-term study in Merino sheep experimentally infected with Mycobacterium avium subsp. paratuberculosis: clinical disease, faecal culture and immunological studies. Vet. Microbiol. 104, 165-178] and Angora goats [Stewart, D.J., Vaughan, J.A., Stiles, P.L., Noske, P.J., Tizard, M.L.V., Prowse, S.J., Michalski, W.P., Butler, K.L., Jones, S.L., 2006. A long-term study in Angora goats experimentally infected with Mycobacterium avium subsp. paratuberculosis: clinical disease, faecal culture and immunological studies. Vet. Microbiol. 113, 13-24], in the same experiments as the Holstein-Friesian cattle, have been described. Two longitudinal experiments involving Holstein-Friesian cattle challenged with either bovine or ovine strains of Mycobacterium avium subsp. paratuberculosis (Map) have been conducted over a period of 54 and 35 months, respectively. Blood samples for the IFN-gamma test and the absorbed ELISA and faecal samples for bacteriological culture were taken pre-challenge and monthly post-challenge. Cell-mediated (CMI) responses were substantially higher for the bovine Map strain during the 42-month period following dosing but then declined in the remaining 12 months. However, for the ovine Map challenge and control groups, CMI responses were not significantly different from each other. None of the cattle developed clinical disease and only one of the cattle in the bovine Map gut mucosal tissue challenged group was a persistent faecal shedder and also an ELISA antibody responder which developed after shedding commenced. Culture of tissues, following necropsy at the completion of the experiments, showed no evidence of infection in any of the challenged cattle and sheep for either the bovine or ovine Map strain in contrast to positive cultures for challenged goats in the same experiments. The tissues from the control cattle, sheep and goats were culture negative. The cattle were less susceptible to the bovine and ovine Map strains than goats and sheep with the goats being the least naturally resistant.

Prevalence of multiresistant Gram-negative organisms in a surgical hospital in Ho Chi Minh Cit, Vietnam

OBJECTIVE

To determine resistance patterns of multiresistant Gram-negative organisms at a surgical hospital in Ho Chi Minh City, Vietnam, in order to guide appropriate antibiotic prescribing and improve infection control procedures.

METHOD

All samples sent in for microbiological analysis over a 3-month period were included. A resource neutral double disc-diffusion test was introduced to detect the presence of extended-spectrum beta-lactamase (ESBL) production.

RESULTS

We obtained 350 bacterial isolates from clinical specimens; 87.4% were Gram-negative bacteria (GNB). Of these, 88.9% were Enterobacteriaceae, of which 14.7% produced ESBL. Fifteen (37.5%) of these were isolated within 48 h of admission. Resistance to gentamicin and ciprofloxacin occurred in 70.0% and 72.5% of those organisms that produced ESBL and in 39.5% and 38.7% of those that did not. Resistance to third-generation cephalosporins was common: 36.7% of all GNB were resistant to ceftriaxone, 34.0% to cefotaxime, 19.6% to ceftazidime and 36.7% to cefoperazone.

CONCLUSION

Multiresistant Gram-negative organisms are common and pose a challenge to antibiotic therapy. Successful implementation of a simple test to detect ESBL production allowed reporting of these organisms, appropriate antibiotic prescribing and infection control interventions. Development of antibiotic-prescribing guidelines must take into account these resistance patterns.

Treatment of patients with atopic dermatitis using wet-wrap dressings with diluted steroids and/or emollients. An expert panel's opinion and review of the literature

BACKGROUND

The use of dampened bandages to reduce inflamed eczema (synonyme dermatitis) is an old remedy. In order to evaluate the current indications for so-called wet-wrap treatment (WWT) for atopic dermatitis (AD), and to compare the different currently recognized methods, a group of experts critically reviewed their own expertise on WWT in respect to the existing literature on the subject.

RESULTS

WWT is well tolerated in eczema due to the cooling effect on the skin and the rapid improvement in skin inflammation. It has been shown to be an extremely effective treatment for acute erythrodermic dermatitis, therapy-resistant AD and intolerable pruritus. Advantages of WWT include rapid response to therapy, reduction in itch and sleep disturbance, and potential for reduction in usage of topical corticosteroids (TCS). However, disadvantages include high cost, the necessity for special training in usage, potential for increased TCS absorption, increased cutaneous infections and folliculitis, and poor tolerability. Precautions to reduce the risks of long-term treatment should include education, monitoring of weight and height and, if necessary, serum cortisol levels. In adolescents the risk of striae from TCS absorption around puberty is high, and WWT with TCS in this age group should be used as a short-term therapy only and with extreme caution. To reduce risks, dilutions of steroids may be used ranging from 5 to 10%. In the maintenance phase this treatment can be rotated with the use of emollients only. Low potency TCS should be used on the face (with a mask).

CONCLUSION

WWT using diluted steroids is a relatively safe addition to the therapeutic treatment options for children and adults with severe and/or refractory AD. Explanation and education is extremely important in the treatment of AD and WWT should only be employed by practitioners trained in its use. Specialized nursing care is essential, especially when using WWT for prolonged periods.

Diagnostic implications of antigen-induced gamma interferon production by blood leukocytes from Mycobacterium bovis-infected reindeer (Rangifer tarandus)

The only approved method of tuberculosis (TB) surveillance of reindeer within the United States is tuberculin skin testing; however, skin testing has an apparent lack of specificity, since numerous reindeer are classified as reactors, yet Mycobacterium bovis is not isolated from tissues upon necropsy. The objective of this study was to evaluate the ability of an in vitro assay (the Cervigam assay) to detect gamma interferon (IFN-gamma) produced by blood leukocytes in response to mycobacterial antigens from M. bovis-infected reindeer. Thirteen male reindeer approximately 9 months of age were inoculated with 10(5) CFU M. bovis in their tonsillar crypts. Stimulation of whole-blood cultures with a mitogen resulted in significant production of IFN-gamma compared to that by nonstimulated samples. Responses by infected reindeer to M. bovis purified protein derivative (PPD) were as much as 3.5-fold higher than those by noninfected reindeer (n = 4). Despite differences in responses to PPD by the two groups, reindeer within the noninfected group had responses of >0.1 change in optical density (DeltaOD) (a level generally considered positive) to PPD. Mean responses by infected reindeer to a rESAT-6-CFP-10 fusion protein (Mycobacterium tuberculosis complex specific) were as much as 20-fold higher than respective responses by noninfected reindeer at all time points. Additionally, responses by 3/4 noninfected reindeer were <0.1 DeltaOD (considered negative) at each time point. To further evaluate the specificity of the assay, samples were collected from reindeer in a TB-free herd. All reindeer had responses to mitogen; however, only 1 of 38 had a response to PPD, and none of the reindeer responded to rESAT-6-CFP-10. Together, these findings indicate that IFN-gamma-based tests may prove useful for TB surveillance of reindeer.

A long-term study in Angora goats experimentally infected with Mycobacterium avium subsp. paratuberculosis: Clinical disease, faecal culture and immunological studies

Two longitudinal experiments involving Angora goats challenged with either bovine or ovine strains of Mycobacterium avium subspecies paratuberculosis (Map) have been conducted over a period of 54 and 35 months, respectively. Blood samples for the interferon-gamma (IFN-gamma) test and the absorbed ELISA and faecal samples for bacteriological culture were taken pre-challenge and monthly post-challenge. Persistent shedding, IFN-gamma production, seroconversion and clinical disease occurred earlier with the bovine Map gut mucosal tissue challenge inoculum than with cultured bacteria. The IFN-gamma responses of the gut mucosal tissue and bacterial challenge groups were substantially and consistently higher than those of the control group. The in vivo and cultured cattle strains were much more pathogenic for goats than the sheep strains with persistent faecal shedding, seroconversion and clinical disease occurring in the majority of bovine Map challenged goats. With the ovine Map, 3 goats developed persistent antibody responses but only one of these goats developed persistent faecal shedding and clinical disease. However, there was no significant difference between the IFN-gamma responses of the tissue challenged, bacterial challenged and control groups. Compared with sheep, the ELISA appeared to have higher sensitivity and the IFN-gamma test lower specificity.

Melanopsin-dependent photoreception provides earliest light detection in the mammalian retina

BACKGROUND

The visual system is now known to be composed of image-forming and non-image-forming pathways. Photoreception for the image-forming pathway begins at the rods and cones, whereas that for the non-image-forming pathway also involves intrinsically photosensitive retinal ganglion cells (ipRGCs), which express the photopigment melanopsin. In the mouse retina, the rod and cone photoreceptors become light responsive from postnatal day 10 (P10); however, the development of photosensitivity of the ipRGCs remains largely unexplored.

RESULTS

Here, we provide direct physiological evidence that the ipRGCs are light responsive from birth (P0) and that this photosensitivity requires melanopsin expression. Interestingly, the number of ipRGCs at P0 is over five times that in the adult retina, reflecting an initial overproduction of melanopsin-expressing cells during development. Even at P0, the ipRGCs form functional connections with the suprachiasmatic nucleus, as assessed by light-induced Fos expression.

CONCLUSIONS

The findings suggest that the non-image-forming pathway is functional long before the mainstream image-forming pathway during development.

Sensitivity of human gamma interferon assay and tuberculin skin testing for detecting infection with Mycobacterium tuberculosis in patients with culture positive tuberculosis

SETTING

Nine university-affiliated chest clinics in Australia.

OBJECTIVE

To evaluate the sensitivity of a whole blood human gamma-interferon assay (HGIA, QuantiFERON-TB) for specific T lymphocyte responses and Tuberculin skin testing (TST) for the detection of Mycobacterium tuberculosis infection in subjects with culture-proven M. tuberculosis disease (TBCP).

DESIGN

Prospective testing of 129 patients with recent TBCP and 100 patients with non-tuberculosis lung disease (NTBLD).

RESULTS

Using a defined level of specific IFN-gamma production and TST 10mm as positive cut-offs, the sensitivity of HGIA was 81% compared to 89% for TST (p=0.06). When positive responses in both TST and HGIA were combined, 96% of TB patients were detected. For the NTBLD group, 43% of whom were born overseas, 73% were negative for both the HGIA and TST. Prior immunization with M. bovis (bacille Calmette-Guerin) (BCG) or the type of TB had no effect on the sensitivities of the assays. For those treated for <2 months, the sensitivities for both assays were 84%, but for those treated for >2 months the sensitivity of TST (90%) tended to be higher than for HGIA (81%) (p=0.07). The distribution of TST results in TB patients showed a broad peak between 10 and 25 mm, while the results in the HGIA were bimodal in both TB and NTBLD patients.

CONCLUSION

HGIA may prove an alternative to skin testing for detecting M. tuberculosis infection in certain settings.

A long-term study in Merino sheep experimentally infected with Mycobacterium avium subsp. paratuberculosis: clinical disease, faecal culture and immunological studies

Two longitudinal experiments involving Merino sheep challenged with either bovine or ovine strains of Mycobacterium avium subsp. paratuberculosis (Map) have been conducted over a period of 54 and 35 months, respectively. Blood samples for the interferon-gamma test, the absorbed ELISA and faecal samples for bacteriological culture were taken pre-challenge and monthly post-challenge. Infections were induced with either a bovine or ovine strain of Map in separate experiments with infections being more easily established, in terms of faecal bacterial shedding and clinical disease when the challenge inoculum was prepared from gut mucosal tissue than cultured bacteria. The patterns of response for shedding and clinical disease were similar. Cell-mediated immune responses were proportionally elevated by at least an order of magnitude in all sheep dosed with either a bovine or ovine strain of Map. Conversely, antibody responses were only elevated in a relatively small proportion of infected sheep. Neither of the clinically affected tissue challenged sheep developed an antibody response despite the presence of persistent shedding and the development and decline in cell-mediated immunity. The results indicated that for sheep the interferon-gamma test may be useful for determining if a flock has been exposed to ovine Johne's disease.

Tuberculosis in Tanzanian Wildlife

Bovine tuberculosis, caused by Mycobacterium bovis, is a pathogen of growing concern in free-ranging wildlife in Africa, but little is known about the disease in Tanzanian wildlife. Here, we report the infection status of Mycobacterium bovis in a range of wildlife species sampled from protected areas in northern Tanzania. M. bovis was isolated from 11.1% (2/18) migratory wildebeest (Connochaetes taurinus) and 11.1% (1/9) topi (Damaliscus lunatus) sampled systematically in 2000 during a meat cropping program in the Serengeti ecosystem, and from one wildebeest and one lesser kudu (Tragelaphus imberbis) killed by sport hunters adjacent to Tarangire National Park. A tuberculosis antibody enzyme immunoassay (EIA) was used to screen serum samples collected from 184 Serengeti lions (Panthera leo) and 19 lions from Ngorongoro Crater sampled between 1985 and 2000. Samples from 212 ungulates collected throughout the protected area network between 1998 and 2001 also were tested by EIA. Serological assays detected antibodies to M. bovis in 4% of Serengeti lions; one positive lion was sampled in 1984. Antibodies were detected in one of 17 (6%) buffalo (Syncerus caffer) in Tarangire and one of 41 (2%) wildebeest in the Serengeti. This study confirms for the first time the presence of bovine tuberculosis in wildlife of northern Tanzania, but further investigation is required to assess the impact on wildlife populations and the role of different wildlife species in maintenance and transmission.

IMMUNE RESPONSES OF WHITE-TAILED DEER (ODOCOILEUS VIRGINIANUS) TO MYCOBACTERIUM BOVIS BCG VACCINATION

The objective was to evaluate cellular immune response of captive white-tailed deer (Odocoileus virginianus) to live Mycobacterium bovis bacille Calmette Guerin (BCG) vaccination and to determine diagnostic implications of these responses. In vitro proliferative and interferon-gamma (IFN-gamma) responses to M. bovis purified protein derivative (PPD) were detected beginning 9 days postvaccination. Responses to Mycobacterium avium PPD, however, generally exceeded responses to M. bovis PPD. Interferon-gamma responses to M. avium PPD were not detected prior to vaccination nor in nonvaccinated deer, suggesting that vaccination with BCG boosted prior quiescent M. avium-sensitized cells. Both CD4+ and gammadelta T cells from vaccinated deer proliferated in response to M. bovis PPD stimulation. Intradermal administration of M. bovis PPD resulted in increases in skin thickness of vaccinated deer beginning 24 hr postinjection. Such early reactions were characterized by edema and minimal mononuclear cell infiltration, whereas later reactions (i.e., 72 hr postinjection) were more typical of delayed type hypersensitivity. Upon in vitro activation with pokeweed mitogen, CD44 expression increased and CD62L expression decreased on lymphocytes from deer regardless of vaccination status. Likewise, M. bovis PPD stimulation of lymphocytes from vaccinated deer resulted in increases in CD44 expression and decreases in CD62L expression. These findings demonstrate the potential of BCG vaccination to elicit strong cell-mediated immune responses and appropriate alterations in CD44 and CD62L expression with in vitro stimulation of white-tailed deer lymphocytes. In relation to M. bovis diagnosis, vaccination of white-tailed deer with BCG can induce skin test responses that classify the animal as a tuberculosis reactor. In contrast, BCG vaccination will likely not interfere with tuberculosis testing by the IFN-gamma assay.

Effects of preexposure to dexfenfluramine, phentermine, dexfenfluramine-phentermine, or fluoxetine on sibutramine-induced hypophagia in the adult rat

The antiobesity drug sibutramine suppresses food intake via inhibition of reuptake of both norepinephrine (NE) and serotonin (5-HT) into brain terminals. The present study examined whether preexposure to other antiobesity drugs (fluoxetine [FLUOX], phentermine [PHEN], and dexfenfluramine [DEX]) that alter noradrenergic and/or serotonergic activity in brain induces tolerance or sensitization to the subsequent hypophagic action of sibutramine. Accordingly, adult male rats were treated (administered orally once per day for 21 days) with DEX (0, 1, or 3 mg/kg) and/or PHEN (0, 5, or 10 mg/kg), alone and in combination, or with the selective 5-HT reuptake inhibitor FLUOX (0, 15, or 30 mg/kg). Daily administration of PHEN persistently reduced food intake and body weight whereas tolerance developed to the hypophagic action of DEX or of FLUOX within the first week of daily administration. Moreover, low doses of DEX (1 mg/kg) and PHEN (5 mg/kg) interacted in a supra-additive manner to inhibit food intake and water intake and decrease body weight over the 21-day exposure period. After a recovery period of 9 days, a series of food intake trials were conducted to assess the hypophagic action of sibutramine (0, 1, 3, and 9 mg/kg po). Preexposure to PHEN (5 or 10 mg/kg), DEX (3 mg/kg), or FLUOX (30 mg/kg) resulted in a significant attenuation of the hypophagia induced by sibutramine over an 8-h, but not a 2-h, testing period. The pattern of cross-tolerance noted in this study is consistent with the observation that sibutramine inhibits eating via an interaction with noradrenergic and serotonergic mechanisms. Whether PHEN and DEX preexposure in humans alters subsequent sibutramine effectiveness is unknown.

Exhaled NO and assessment of anti-inflammatory effects of inhaled steroid: dose-response relationship

Exhaled nitric oxide (eNO) is an easily measured marker of airway inflammation. This study was undertaken to evaluate the usefulness of serial eNO in investigating the dose-response relationship for inhaled beclomethasone (BDP), and to compare eNO with other markers of airway inflammation. Following withdrawal of inhaled corticosteroid (ICS) therapy, 65 patients entered a double-blind, parallel-group, placebo-controlled trial of 50, 100, 200 or 500 microg x BDP x day(-1) for eight weeks. eNO and spirometry were performed weekly and a hypertonic saline challenge with sputum induction was performed at the beginning and end of treatment. The relationship between the dose of ICS and changes in eNO and forced expiratory volume in one second (FEV1) was linear at 1 week and at the end of treatment. A linear dose-response relationship was also seen for sputum eosinophils. Changes in eNO correlated significantly with changes in sputum eosinophils. Changes in the provocative dose of saline causing a 15% fall in FEV1 saline did not differ across the treatment groups nor did they correlate with changes in other measurements. Exhaled nitric oxide may be used to assess the dose-response relationship for the anti-inflammatory effects of inhaled beclomethasone. The relationship found in this study was linear over the dose range 0-500 microg x day(-1) soon after commencing therapy and continued over time.

The effects of cyclo-oxygenase inhibitors on bile-injured and normal equine colon

A potential adverse effect of cyclo-oxygenase (COX) inhibitors (nonsteroidal anti-inflammatory drugs [NSAIDs]) in horses is colitis. In addition, we have previously shown an important role for COX-produced prostanoids in recovery of ischaemic-injured equine jejunum. It was hypothesised that the nonselective COX inhibitor flunixin would retard repair of bile-injured colon by preventing production of reparative prostaglandins, whereas the selective COX-2 inhibitor, etodolac would not inhibit repair as a result of continued COX-1 activity. Segments of the pelvic flexure were exposed to 1.5 mmol/l deoxycholate for 30 min, after which they were recovered for 4 h in Ussing chambers. Contrary to the proposed hypothesis, recovery of bile-injured colonic mucosa was not affected by flunixin or etodolac, despite significantly depressed prostanoid production. However, treatment of control tissue with flunixin led to increases in mucosal permeability, whereas treatment with etodolac had no significant effect. Therefore, although recovery from bile-induced colonic injury maybe independent of COX-elaborated prostanoids, treatment of control tissues with nonselective COX inhibitors may lead to marked increases in permeability. Alternatively, selective inhibition of COX-2 may reduce the incidence of adverse effects in horses requiring NSAID therapy.

The expression of Fos-labeled spinal neurons in response to colorectal distension is enhanced after chronic spinal cord transection in the rat

The present study used Fos-like immunoreactivity to examine neuronal activation in response to colorectal distension in rats at 1 day or 30 days following spinal cord transection or sham transection. Fifty-five Wistar rats were anesthetized and an incision was made to expose the T(5) spinal segment. The dura was reflected away in all rats and a complete transection at the rostral end of the T(5) segment was given to the lesioned group. At 1 day (acute) or 30 days (chronic) post-surgery, conscious rats were subjected to a 2 h period of intermittent colorectal distension. Rats were perfused and spinal segments L(5)-S(2) were removed and processed for Fos-like immunoreactivity. Spinal cord transection alone had no effect on Fos-labeling in either acute or chronic rats. In acute rats, colorectal distension produced significant increases in Fos-labeling in the superficial and deep dorsal horn regions. In chronic rats, colorectal distension produced a three-fold increase in Fos-labeled neurons that was manifest throughout all laminar regions. These results indicate that the number of neurons expressing Fos in response to colorectal distension is much greater after a chronic spinal cord transection than after an acute transection. Since Fos is an indicator of neuronal activation, the results show that many more neurons become active in response to colorectal distension following a chronic spinal injury. This suggests that a functional reorganization of spinal circuits occurs following chronic spinal cord transection. This may ultimately result in altered visceral and somatic functions associated with spinal cord injury in humans.

Pharmacokinetics of azithromycin in foals after i.v. and oral dose and disposition into phagocytes

The properties of azithromycin suggest that it may be an alternative to erythromycin for treatment of Rhodococcus equi pneumonia in foals. To investigate this possibility, the disposition of azithromycin in plasma, polymorphonuclear leukocytes (PMN), and alveolar cells was examined after a single administration in foals. Azithromycin suspension was administered orally (p.o.) at a dose of 10 mg/kg to five healthy 2-3-month-old foals. Two weeks later, azithromycin for injection was administered by intravenous (i.v.) infusion at a dose of 5 mg/kg to the same foals. Plasma samples were collected after p.o. and i.v. administration. Peripheral blood PMN and bronchoalveolar lavage fluid and alveolar cells were collected after p.o. administration. Azithromycin concentrations were determined by reverse-phase high-performance liquid chromatography (HPLC) with coulometric electrochemical detection. Azithromycin p.o. absorption was variable with a mean systemic availability of 39% (+/-20%). The plasma half-life was 16 and 18.3 h after i.v. and p.o. administration, respectively. Azithromycin had a very large volume of distribution (V(d)) of 11.6 L/kg [V(d(ss))] and 12.4 L/kg [V(d(area))]. The large V(d) can be attributed to high tissue and intracellular concentrations, exhibited by the high concentration of azithromycin in PMN and alveolar cells. The PMN half-life was 49.2 h. Dosage of 10 mg/kg of azithromycin p.o. once daily for foals with R. equi pneumonia is recommended for further study.

Electronic journals: are they a paradigm shift?

Ejournals are becoming an accepted and necessary means of meeting the demands for the dissemination of knowledge. This introductory article discusses the recent "explosion" of ejournals and provides an explanation of what is meant by an "ejournal." Ejournals are explored within the traditional context of scholarship and a discussion of the "serials crisis" that promoted the inception of ejournals is presented. After laying the groundwork for discussing scholarship in this new age of dissemination of scholarly information, the article discusses whether this digital form of publication can be called a "paradigm shift" in Kuhn's (1970) traditional sense of the word.

Quality of treatment following police detention of mentally disordered offenders

There is a growing interest in patients' perspectives in relation to the treatment and management of mentally disordered offenders at all levels of service delivery. This paper reports on a group of mentally ill individuals who were admitted to a place of safety following detention by the police. The principal purpose of the study was to determine the quality of care that the patient experienced under section 136 of the Mental Health Act (1983) from police detention to hospital admission. The major focus concerned the anticipated disparity between the non-professional police interactions and those of the mental health professional. The method employed was a grounded theory analysis of audio-taped interviews utilizing a three-level coding of data. The results indicated a general dissatisfaction with the quality of care and treatment from both police and professionals, but with the former being viewed as acceptable whilst the latter was considered unacceptable. The patients made a series of recommendations for detention in places of safety.

Signaling mechanism for equine neutrophil activation by immune complexes

Neutrophils (PMN) are critical host defense cells that have a role in the pathophysiology of a variety of inflammatory diseases, particularly those diseases associated with antigen-antibody immune complexes (IC) deposited in tissues. Activation of PMN by IC is most efficient if the IC are presented immobilized on a surface. Adhesion to the immobilized IC is important for subsequent activation of PMN effector functions, such as generation of reactive oxygen metabolites. Adhesion of human PMN to immobilized IC requires the expression and activation of adhesion receptors called integrins. Of the integrins expressed on PMN, the beta 2 family has been found to be of particular importance for PMN function. The mechanism of beta 2 integrin activation during adhesion to IC has been studied in human PMN, but not in equine PMN. We show here that adhesion of equine PMN to immobilized IC requires beta 2 integrins. Like adhesion, IC-induced respiratory burst activity is dependent on beta 2 integrins. Furthermore, the signaling pathway triggering beta 2 integrin-dependent adhesion of equine PMN to IC and subsequent generation of respiratory burst activity is inhibited by the specific phosphatidylinositol 3-kinase (PI3K) antagonists wortmannin and LY294002 with IC(50) (concentration at which 50% inhibition is achieved) similar to the published values for inhibition of PI3K enzymatic activity. In contrast, PMA-induced activation of beta 2 integrin-dependent adhesion and respiratory burst activity are wortmannin and LY294002 insensitive. These data demonstrate that like in human PMN, IC-induced activation of beta 2 integrins and beta 2 integrin-dependent functions in equine PMN is dependent on PI3K activity.

BOVIGAM: an in vitro cellular diagnostic test for bovine tuberculosis

BOVIGAM which is based on the detection of gamma interferon (IFN- gamma) is a rapid, laboratory assay of a cell mediated immune response that may be used for the detection of tuberculosis (TB) infection in animals. Whole blood is first incubated overnight with bovine PPD, avian PPD or negative control antigens, and IFN- gamma in the supernatant plasma is then measured by EIA. TB infection is indicated by a predominant IFN- gamma response to bovine PPD. Since 1988, BOVIGAM has been extensively trialed on more than 200 000 cattle in Australia, Brazil, Ireland, Northern Ireland, Italy, New Zealand, Romania, Spain and the USA. Sensitivity has varied between 81.8% and 100% for culture-confirmed bovine TB and specificity between 94% and 100%. The IFN- gamma assay detects M. bovis infection earlier than the skin test and in New Zealand is applied to detect skin-test negative cattle with TB, where after slaughter a significant number of IFN- gamma reactors have TB. BOVIGAM is also approved in New Zealand for serial testing skin test positive cattle when non-specificity is suspected. Cattle are tested 7-30 days after a positive caudal fold test. The boosting effect of the skin test on T-cell activity allows blood to be cultured with PPD up to 30 h after collection without effecting accuracy. The BOVIGAM results are not affected by poor nutritional condition and are only mildly and briefly affected by dexamethasone treatment and parturition. IFN- gamma responses of cattle vaccinated with BCG are dose-dependent and short-lived. The BOVIGAM kit is now used routinely in many countries for the detection of M. bovis infected cattle, buffalo and goats.

The predictive value of exhaled nitric oxide measurements in assessing changes in asthma control

Exhaled nitric oxide (eNO) levels are increased in untreated or unstable asthma and measurements can be made easily. Our aim was to assess the usefulness of eNO for diagnosing and predicting loss of control (LOC) in asthma following steroid withdrawal. Comparisons were made against sputum eosinophils and airway hyperresponsiveness (AHR) to hypertonic saline (4.5%). Seventy-eight patients with mild/moderate asthma had their inhaled steroid therapy withdrawn until LOC occurred or for a maximum of 6 wk. Sixty (77.9%) developed LOC. There were highly significant correlations between the changes in eNO and symptoms (p < 0.0001), FEV(1) (p < 0.002), sputum eosinophils (p < 0.0002), and saline PD(15) (p < 0.0002), and there were significant differences between LOC and no LOC groups. Both single measurements and changes of eNO (10 ppb, 15 ppb, or an increase of > 60% over baseline) had positive predictive values that ranged from 80 to 90% for predicting and diagnosing LOC. These values were similar to those obtained using sputum eosinophils and saline PD(15) measurements. We conclude that eNO measurements are as useful as induced sputum analysis and AHR in assessing airway inflammation, with the advantage that they are easy to perform.

The Future of Antiinflammatory Therapy

The cells and mediators that make up the inflammatory response have the potential to injure tissues and contribute to the pathophysiology of many inflammatory diseases. Strategies to reduce neutrophil migration into sites of inflammation and subsequent activation by inhibiting integrin-mediated adhesion hold promise for successful treatment of a variety of inflammatory diseases. New pharmacologic agents that specifically target prostanoid mediators of inflammation by specifically inhibiting the activity of cyclooxygenase 2 are potent antiinflammatory agents with fewer gastrointestinal side effects than nonspecific cyclooxygenase inhibitors. These areas of antiinflammatory research are rapidly yielding drugs with diverse future applications in equine medicine.

Neodymium:yttrium-aluminum-garnet laser ablation of a urethral web to relieve urinary outflow obstruction in a horse

An 8-year-old Hanoverian gelding was examined because of urine dribbling and urethral obstruction. Mild proprioceptive deficits of the left hind limb were evident during neurologic examination. Ultrasonography per rectum revealed dilatation of the pelvic portion of the urethra. Endoscopy of the urethra revealed 2 webs of tissue: 1 was located 10 cm proximal to the external urethral opening; the other was located 65 cm proximal to the external urethral opening and prevented passage of the endoscope into the urinary bladder. The mass was ablated with a neodymium:yttrium-aluminum-garnet laser, using a transendoscopic noncontact technique. On follow-up examination 6 months after laser surgery, an endoscope could easily be passed into the bladder, and no urethral web was seen. The horse was able to void a stream of urine but continued to dribble urine intermittently. The proximal location of the urethral lesion in this horse would have made use of traditional surgical methods problematic, whereas transendoscopic laser photoablation was easy and effective.