Serratospiculosis in falcons from Kuwait: incidence, pathogenicity and treatment with melarsomine and ivermectin

The aims of this study were to determine the incidence of the filarial avian nematode Serratospiculum seurati in falcons from Kuwait, report clinical signs and find an effective therapy. Naturally occurring S. seurati infestation was diagnosed in 149 (8.7%) out of 1,706 captive falcons examined between May 2003 and April 2005, and 140 of these were treated with melarsomine at dosage of 0.25 mg/kg injected intramuscularly for two days, and ivermectin, injected once at the dose of 1 mg/kg, 10 days later. Infestation was reportedly symptomatic in 107 (71.8%) and non-symptomatic in 42 (28.2%) falcons. Signs reported more often were dyspnoea (58.8%), reduced speed and strength in flight (56%), weight loss (38.3%), anorexia/poor appetite (22.4%) and lethargy (16.8%). After administration of melarsomine, signs disappeared within 1-10 days in symptomatic birds and improvement of flight performances was noted in non-symptomatic birds. Dead adult parasites were ejected in 22 cases. Embryonated eggs were not detected in coproscopic checks made 10 and 40 days after the end of therapy, in association with lasting clinical remission. The main conclusion is that Serratospiculum seurati is overall pathogenic for birds of prey in the Middle East and that melarsomine + ivermectin can be an effective protocol of therapy eliminating both clinical signs and parasites.     

Highly (H5N1) and low (H7N2) pathogenic avian influenza virus infection in falcons via nasochoanal route and ingestion of experimentally infected prey

An experimental infection with highly pathogenic avian influenza (HPAI) and low pathogenic avian influenza (LPAI) viruses was carried out on falcons in order to examine the effects of these viruses in terms of pathogenesis, viral distribution in tissues and viral shedding. The distribution pattern of influenza virus receptors was also assessed. Captive-reared gyr-saker (Falco rusticolus x Falco cherrug) hybrid falcons were challenged with a HPAI H5N1 virus (A/Great crested grebe/Basque Country/06.03249/2006) or a LPAI H7N2 virus (A/Anas plathyrhynchos/Spain/1877/2009), both via the nasochoanal route and by ingestion of previously infected specific pathogen free chicks. Infected falcons exhibited similar infection dynamics despite the different routes of exposure, demonstrating the effectiveness of in vivo feeding route. H5N1 infected falcons died, or were euthanized, between 5-7 days post-infection (dpi) after showing acute severe neurological signs. Presence of viral antigen in several tissues was confirmed by immunohistochemistry and real time RT-PCR (RRT-PCR), which were generally associated with significant microscopical lesions, mostly in the brain. Neither clinical signs, nor histopathological findings were observed in any of the H7N2 LPAI infected falcons, although all of them had seroconverted by 11 dpi. Avian receptors were strongly present in the upper respiratory tract of the falcons, in accordance with the consistent oral viral shedding detected by RRT-PCR in both H5N1 HPAI and H7N2 LPAI infected falcons. The present study demonstrates that gyr-saker hybrid falcons are highly susceptible to H5N1 HPAI virus infection, as previously observed, and that they may play a major role in the spreading of both HPAI and LPAI viruses. For the first time in raptors, natural infection by feeding on infected prey was successfully reproduced. The use of avian prey species in falconry husbandry and wildlife rehabilitation facilities could put valuable birds of prey and humans at risk and, therefore, this practice should be closely monitored.     

Role of T cell subsets in the modulation of Mycobacterium avium growth within human monocytes

Mycobacterium avium frequently causes disseminated disease in patients with advanced AIDS with low CD4 counts. The effects of T lymphocyte on intracellular M. avium replication were examined. Plastic adherent monocytes and nonadherent lymphocytes were separated from peripheral blood mononuclear cells. After infection with M. avium, monocytes were cultured with or without autologous lymphocytes (1-10 cells/monocyte) for up to 7 days. Addition of lymphocytes to M. avium-infected monocytes significantly decreased intracellular M. avium growth after 7 days culture (n = 11, P < 0.01, paired t test) and increased IFN-gamma production compared to monocytes alone. Neutralizing IFN-gamma partially abrogated lymphocyte activity. CD4 depletion diminished anti-mycobactericidal effects and CD8(+) lymphocytes increased intracellular M. avium growth (P < 0.05, n = 5, t test). These data suggest that interactions between monocytes and nonadherent cell fractions such as CD4(+) T cells and NK cells are important in intracellular M. avium growth modulation in monocytes from healthy humans.     

Avian tuberculosis in wild birds in the Netherlands

Mycobacterium avium was isolated from 82 of 11,664 birds submitted for necropsy in The Netherlands. All isolated M. avium strains belonged to serotype 1, 2 or 3. The greatest number M. avium were from buzzards and falcons. The prevalence of tuberculosis in gulls is extremely low.     

Efficacy of ivermectin (Ivomec) against intestinal capulariosis in falcons

52 captive falcons out of 3,988 (1.3 %) raptors microscopically examined for intestinal parasites in the Middle East proved infested with hairworms (capillariid parasites). 26 of these (50 %) showed concurrent parasitoses. In the group of 26 falcons diagnosed with capillariosis as sole infestation (50 %) compatible clinical signs such as anorexia, weight loss, weakness, dyspnoea, regurgitation of food and blood, diarrhoea and dark tarry faeces, were recorded. These birds were treated intramuscularly with ivermectin at doses of 2 mg/kg. In fecal samples examined 10-15 days later, the eggs of capillariid parasites had disappeared, in association with complete clinical recovery.     

A Curcumin‐Based 1‐Week Triple Therapy for Eradication of Helicobacter pylori Infection: Something to Learn From Failure?

BACKGROUND: Curcumin is the principal element of turmeric powder extracted from the root of Curcuma longa. Studies on curcumin have demonstrated some anti-Helicobacter pylori activity as well as immunomodulating properties. N-acetylcysteine and lactoferrin with their respective mucolytic and antibacterial activities might also be effective in H. pylori eradication therapy. AIM: To determine if a 7-day non-antibiotic therapy comprised of curcumin, lactoferrin, N-acetylcysteine, and pantoprazole was effective for eradication of H. pylori infection and reduction of gastric inflammation, assessed by serum pepsinogens and relief of symptoms. SUBJECTS AND METHODS: Twenty-five consecutive H. pylori-positive patients (12 males, mean age 50 +/- 12 years, range 31-76) with functional dyspepsia were enrolled. Patients were administered for 7 days curcumin 30 mg b.i.d., bovine lactoferrin 100 mg b.i.d., N-acetylcysteine 600 mg b.i.d., and pantoprazole 20 mg b.i.d. H. pylori status and upper gastrointestinal symptoms were assessed by (13)C-urea breath test and a scale of upper gastrointestinal symptoms intensity (absent, mild, moderate, and severe), as well as a blood test for serum pepsinogens (sPGI, sPGII), gastrin-17 (G-17), and anti-H. pylori IgG (IgG-Hp) at baseline (T0) and after 2 months (T1). RESULTS: Three of 25 patients (12%) were cured of H. pylori infection. A significant decrease in the overall severity of symptoms (T0: 6, interquartile range [IQR]: 4.5-8; T1: 2, IQR: 2-3; p < or = .001), and sPGII (T0: 16 microg/L, IQR: 13-22; T1: 10 microg/L, IQR: 8-16; p < or = .001) and sPGI (T0: 82 microg/L, IQR: 67-97; T1: 74 microg/L, IQR: 62-94; p = .02) levels were observed after 2 months of the treatment. IgG and G-17 values did not significantly decrease after 2 months. CONCLUSIONS: This novel therapy was not effective for H. pylori eradication. However, despite the bacterium persistence, significant improvement of dyspeptic symptoms and reduction of serologic signs of gastric inflammation were observed after 2 months at the end of the 7-day treatment schedule.     

Fluorescent acid-fast microscopy for measuring phagocytosis of Mycobacterium avium, Mycobacterium intracellulare, and Mycobacterium scrofulaceum by Tetrahymena pyriformis and their intracellular growth

Fluorescent acid-fast microscopy (FAM) was used to enumerate intracellular Mycobacterium avium, Mycobacterium intracellulare, and Mycobacterium scrofulaceum in the ciliated phagocytic protozoan Tetrahymena pyriformis. There was a linear relationship between FAM and colony counts of M. avium cells both from cultures and within protozoa. The Ziehl-Neelsen acid-fast stain could not be used to enumerate intracellular mycobacteria because uninfected protozoa contained acid-fast, bacterium-like particles. Starved, 7-day-old cultures of T. pyriformis transferred into fresh medium readily phagocytized M. avium, M. intracellulare, and M. scrofulaceum. Phagocytosis was rapid and reached a maximum in 30 min. M. avium, M. intracellulare, and M. scrofulaceum grew within T. pyriformis, increasing by factors of 4- to 40-fold after 5 days at 30 degrees C. Intracellular M. avium numbers remained constant over a 25-day period of growth (by transfer) of T. pyriformis. Intracellular M. avium cells also survived protozoan encystment and germination. The growth and viability of T. pyriformis were not affected by mycobacterial infection. The results suggest that free-living phagocytic protozoa may be natural hosts and reservoirs for M. avium, M. intracellulare, and M. scrofulaceum.     

Effects of sulfadiazine and amprolium on Neospora caninum (Protozoa: Apicomplexa) infections in mice

An immunosuppressed mouse model was used to determine the effects of amprolium and sulfadiazine on experimental Neospora caninum infections. Both drugs were given in the drinking water. Neither drug was effective in treating infections when given 7 days after inoculation of tachyzoites, when clinical signs of disease had developed. Amprolium did not prevent deaths or development of clinical signs when given in the drinking water at 1 mg/ml or 5 mg/ml 3 days after inoculation of tachyzoites. Sulfadiazine in drinking water was not effective when given at 0.5 mg/ml but was effective in preventing deaths and clinical disease when given at 1 mg/ml 3 days after inoculation with tachyzoites. Most mice (6 of 10) treated for 3 days with 1 mg/ml sulfadiazine in drinking water developed encephalitis after drug treatment was stopped. Treatment for 14 days with 1 mg/ml sulfadiazine in drinking water was needed to protect 90% of inoculated mice.     

The efficacy of 2,3-dimercaptopropanol and D-penicillamine on methyl mercury induced neurological signs and weight loss

In order to test the effectiveness of complexing therapy on methyl mercury induced neurotoxicity, female rats were treated for five days with either 2,3-dimercaptopropanol (BAL) or D-penicillamine (DPA) beginning 1 or 12 days after the final dose of methyl mercury hydroxide (MMOH). MMOH was administered orally at a dose of 13.3 mg/kg once each day for 3 successive days. BAL, dissolved in peanut oil, was administered sc in a dose of 30 mg/kg twice each treatment day. DPA was dissolved in water and administered sc in a dose of 1200 mg/kg once each treatment day. Therapy begun 1 day after the last MMOH administration was prior to the appearance of toxic signs but therapy begun 12 days later was after signs had developed. The ability of BAL or DPA therapy to alter the distribution of radio-labelled (²⁰³Hg) MMOH was determined. Both DPA and BAL significantly reduced tissue concentrations of mercury when administered beginning 1 day after MMOH, but only DPA was effective in removing mercury from tissues when treatment was begun 12 days after the last dose of MMOH. In a separate experiment when either BAL or DPA therapy was initiated as above 1 day after the last dose of MMOH, the appearance of neurological signs of toxicity was prevented and weight loss was reversed. When therapy was initiated the twelfh day after the last MMOH dose, neither BAL nor DPA was effective in reversing either neurotoxic signs or weight loss. Therefore, therapy is ineffective in reversing neurological signs if it is delayed too long after MMOH administration, even though it is effective in reducing tissue mercury levels.     

Lethal granuloma disintegration in mycobacteria-infected TNFRp55-/- mice is dependent on T cells and IL-12

Genetically susceptible, TNFRp55 gene-deficient (TNFRp55-/-) mice succumb to infection with Mycobacterium avium. Before their death, M. avium-infected TNFRp55-/- mice develop granulomatous lesions that, in contrast to granulomas in wild-type syngeneic mice, undergo acute disintegration. To determine the factors involved in these events, we depleted T cell subsets or neutralized the inflammatory cytokines IFN-gamma, IL-12, or TNF in TNFRp55-/- mice infected i.v. with M. avium. Infected TNFRp55-/- mice treated with a control mAb became moribund between days 26 and 34 postinfection, showing widespread inflammatory cell apoptosis within disintegrating granulomas. In contrast, TNFRp55-/- mice depleted of either CD4+ or CD8+ cells after granuloma initiation stayed healthy until at least day 38 postinfection and showed no signs of granuloma destruction. Neutralization of IL-12, but not of IFN-gamma or TNF, also protected M. avium-infected TNFRp55-/- mice from granuloma decomposition and from premature death. Treatment with dexamethasone or with a specific inhibitor of inducible NO synthase did not prevent granuloma dissolution or death of TNFRp55-/- mice. In conclusion, granuloma disintegration in TNFRp55-/- mice is a lethal event that is dependent on IL-12 and that is mediated by an excess of T cells.     

Experimental rabies in a great horned owl

A great horned owl (Bubo virginianus) was fed the carcass of an experimentally infected rabid skunk. The bird developed antibody titer to rabies, detected by passive haemagglutination, 27 days after oral inoculation by ingestion. The owl suppressed the infection until corticosteroid administration, after which a maximum antibody titer was attained. Evidence of active rabies viral infection was seen by fluorescent antibody staining of oral swabs, corneal impression smears and histologic tissue smears, by suckling mouse inoculation of oral swab washings, and by transmission electron microcopy. No clinical signs of rabies virus infection were observed.     

The passive transfer of severe allergic neuritis in Lewis rats with lymphoid cells preincubated with P2 protein

The passive transfer of both clinical signs and histologic lesions characteristic of allergic neuritis was successfully performed in Lewis rats using pooled spleen and lymph node cells, or T lymphocytes therefrom, if first preincubated in petri dishes with P2 protein for 72 hr. For passive transfer, cells were taken from donors 8-16 days after sensitization with P2 protein or myelin in Freund's complete adjuvant, and administered via the tail vein; clinical signs appeared 12-13 days later. This study supports the importance of cell-mediated immunity in EAN and the antigenic role of the P2 protein.     

Syngeneic fibroblasts transfected with a plasmid encoding interleukin-4 as non-viral vectors for anti-inflammatory gene therapy in collagen-induced arthritis

Background

No effective long‐term treatment is available for rheumatoid arthritis. Recent advances in gene therapy and cell therapy have demonstrated efficiency in collagen‐induced arthritis (CIA). Interleukin‐4 (IL‐4) is already known to be efficient in CIA in systemic injection or administered by gene therapy. This study was designed to evaluate the effect of a non‐viral gene therapy of CIA, involving injection of syngeneic fibroblasts transfected with a plasmid encoding for IL‐4.

Methods

Immortalised fibroblasts from DBA/1 mice (DBA/1/0 cells) were transfected with a plasmid expressing IL‐4 cDNA (DBA/1/IL‐4 cells). Xenogeneic fibroblasts from Chinese hamster ovary (CHO) transfected with a plasmid expressing IL‐4 cDNA (CHO/IL‐4) were studied also. The cells were engrafted in mice developing CIA by subcutaneous injection of 3 × 10⁶ DBA/1/0 or DBA/1/IL‐4 or CHO/IL‐4 cells.

Results

Injection of DBA/1/IL‐4 cells, on days 10 and 25 after immunisation, was associated with a significant and lasting improvement in the clinical and histological evidence of joint inflammation and destruction as compared with DBA/1/0 and CHO/IL‐4 cells. DBA/1/IL‐4 cell treatment decreased also the production of IgG2a antibody to CII and the proliferation of CIIB‐specific nodal T cells. Later treatments (engraftments on days 23 and 35 after immunisation) exerted also an anti‐inflammatory effect, as evaluated on clinical and histological signs of CIA.

Conclusions

Taken together, these findings indicate that systemic administration of syngeneic cells transfected with an anti‐inflammatory cytokine gene, namely IL‐4, with a non‐viral method is effective in CIA and may attenuate the cytokine imbalance seen in this disease. Copyright © 2002 John Wiley & Sons, Ltd.

     

First postpartum estrus and pregnancy in the female collared peccary (Tayassu tajacu) from the amazon

The onset of sexual cycle postpartum was described in the collared peccary (Tayassu tajacu). Serum progesterone and 17beta-estradiol profiles, vaginal smears and external genitalia were analyzed in 20 animals housed with their piglets during the first postpartum month. The appearance of external genitalia showed no variation in any of the females: a shallow, reddish vulva, and vaginal mucus were constant features throughout the study. Based on hormonal profiles and vaginal smear cell patterns, 16 (80%) of the 20 peccaries showed signs of estrus and were considered cycling. The remaining four females (20%) did no show signs of estrus confirmed by low levels of progesterone (0.9+/-0.4 ng/mL) during the first postpartum month. In the cycling peccaries, a serum 17beta-estradiol peak (53.4+/-8.1 pg/mL) was observed on Day 7+/-1 postpartum, along with a linear increase in progesterone concentration from 3 (4.3+/-2.6 ng/mL) to 11 (30.8+/-4.9 ng/mL) days after this estradiol peak. Proportions of the different cells of the vaginal epithelium also changed in these females: superficial plus intermediate cells amounted to 76% of the cell total between Days 6 and 9 postpartum, corresponding to the estradiol peak. Nine (56%) of the 16 cycling females mated, indicated by the presence of sperm cells in their vaginal smears, and 6 (67%) became pregnant, reaching term. Non-pregnant cycling females (n=10) showed a steady decrease in serum progesterone concentration from 11 to 23 days after the estradiol peak, when basal levels were attained and a new estradiol peak registered, indicating the resumption of cyclicity in these females. The time interval between the two estradiol peaks was 23.5+/-2.1 days in these females. In pregnant females, progesterone concentrations continued to rise to levels of 60 ng/mL (n=6) 23 days after mating. These findings indicate that the lactating collared peccary female can become cycling and fertile during the early postpartum period, and that a predominance of superficial plus intermediate vaginal cells can be taken as the first sign of estrus.     

Detection of Toxoplasma gondii parasitemia in experimentally inoculated cats

Toxoplasma gondii B1 gene polymerase chain reaction (PCR) amplification utilizing a flanking and nesting reaction was compared to mouse bioassay on feline whole blood samples collected before and after experimental inoculation with T. gondii. Samples were collected from 5 cats prior to inoculation with T. gondii and on days 3, 7, 10, 14, 21, 28, 35, 42, 49, 56, 63, 70, 84, 112, 140, 143, 147, 150, 154, 161, 168, 175, and 182 after inoculation. Cats were challenged with T. gondii orally on day 140. Bioassay was found to be less effective for detection of parasitemia than B1 gene PCR. Parasitemia was detected in all 5 cats by PCR multiple times after primary and challenge inoculation. Detection of T. gondii parasitemia by PCR utilizing the flanking reaction described here may be useful in predicting the oocyst shedding period in individual cats. As none of the cats developed signs of systemic illness, yet were chronically parasitemic, T. gondii whole-blood PCR is not helpful as a diagnostic test for clinical feline toxoplasmosis.     

Peptide 53-78 of myelin P2 protein is a T cell epitope for the induction of experimental autoimmune neuritis.

We have recently described the clinical and pathological features of experimental autoimmune neuritis (EAN) in Lewis rats inoculated with varying doses of a synthetic peptide corresponding to the amino acid residues 53-78 of bovine P2 protein (SP-26). Immunization with this synthetic peptide was able to induce severe clinical and pathological characteristics of EAN. We are now reporting that, SP-26 T cell lines derived from spleen and lymph node cell populations of such immunized rats, upon being triggered by SP-26, can adoptively transfer severe clinical and histological signs of EAN to naive syngeneic recipients. The disease appears 7-8 days postinoculation of the cells and persist 5-10 days. The pathological features were indistinguishable from SP-26-induced active EAN which appears 12-15 days after sensitization. Examination of the surface phenotype of the cells that were used for the passive transfer of EAN by FACS analysis, showed majority of the cells to be CD4+, Ia+ cells.     

UV light inactivation of Mycobacterium avium subsp. paratuberculosis in milk as assessed by FASTPlaqueTB phage assay and culture

UV light inactivation of Mycobacterium avium subsp. paratuberculosis in Middlebrook 7H9 broth and whole and semiskim milk was investigated using a laboratory-scale UV machine that incorporated static mixers within UV-penetrable pipes. UV treatment proved to be less effective in killing M. avium subsp. paratuberculosis suspended in milk (0.5- to 1.0-log(10) reduction per 1,000 mJ/ml) than that suspended in Middlebrook 7H9 broth (2.5- to 3.3-log(10) reduction per 1,000 mJ/ml). The FASTPlaqueTB phage assay provided more rapid enumeration of surviving M. avium subsp. paratuberculosis (within 24 h) than culture on Herrold's egg yolk medium (6 to 8 weeks). Despite the fact that plaque counts were consistently 1 to 2 log(10) lower than colony counts throughout the study, UV inactivation rates for M. avium subsp. paratuberculosis derived using the phage assay and culture results were not significantly different (P = 0.077).     

Treatment of experimental disseminated Mycobacterium avium complex infection in mice with recombinant IL-2 and tumor necrosis factor

Mycobacterium avium complex (MAC) is the most common bloodstream pathogen isolated from patients with AIDS. We have previously shown that TNF alone or in combination with IL-2 can activate human and murine macrophages in vitro to kill MAC strains isolated from disseminated infections. To determine whether treatment with TNF and IL-2 could effect the course of disseminated MAC infections in a murine model of disseminated MAC infection, we infected C57BL mice with 3 x 10(8) bacteria i.v. and 1 wk later administered: 1) IL-2, 100 micrograms/kg; 2) TNF, 25 micrograms/kg; 3) IL-2, 50 micrograms/kg, and TNF, 12.5 micrograms/kg; and 4) saline. IL-2 was injected i.p. daily with TNF being administered in cycles of 3 out of 4 consecutive days. Fourteen days after starting therapy, blood was cultured and mice were sacrificed for quantitative cultures of liver and spleen homogenates. IL-2, TNF, and IL-2/TNF treated groups showed an 87 +/- 5%, 57 +/- 9%, 88 +/- 6% decrease in bacteremia (p = 0.05 for TNF-treated animals and less than 0.04 for the other two groups, compared with control). The combination IL-2/TNF was the only treatment that showed a trend toward an absolute decrease in the number of bacteria in the blood. Reduction in colony counts of liver and spleen were 77 +/- 4% and 87 +/- 6%, respectively, for treatment with IL-2, 58 +/- 7% and 87 +/- 5% for TNF, and 60 +/- 10% and 82 +/- 6% for IL-2/TNF, respectively. These results suggest that both cytokines may play a role in the control of Mycobacterium avium infection and that the combination of a half-dose of IL-2 and TNF, despite not showing any greater efficacy, can be less toxic than TNF or IL-2 alone and might be useful for the therapy of disseminated infection.