Inflammatory responses to migrating Brugia pahangi third-stage larvae.

Despite being central to parasite establishment and subsequent host pathological and immunologic responses, host-parasite interactions during early third-stage filarial larva (L3) migration are poorly understood. These studies aimed to define early tissue migration of Brugia pahangi L3 in the gerbil (Meriones unguiculatus) and measure host cellular responses during this period. Gerbils were intradermally inoculated in the hind limb with 100 B. pahangi L3, and necropsies were performed at various times. At 3 h, most L3 (96.3%) were recovered from tissues associated with the infection site, with marked L3 migration occurring by 24 h. Larvae were dispersed throughout the lymphatics at 7 days postinfection (dpi), and at 28 dpi, most parasites were recovered from the spermatic cord lymphatics. Parasites were identified histologically at all time points. Inflammatory cells, primarily neutrophils, were frequently observed around larvae in the dermis and muscle near the injection site at 3 h and 24 h. Levels of interleukin-6 (IL-6) and tumor necrosis factor-alpha mRNA peaked at 3 h in all tissues, with IL-6 levels also high in the spleen at 28 dpi. Levels of IL-4 mRNA were elevated in all tissues at 28 dpi. These observations demonstrate that L3 migrate quickly through various tissues and into lymph nodes in a predictable pattern. Migrating L3 induce an early acute inflammatory response that is modulated as parasites establish in the lymphatics. Polarization of the host response towards a dominant Th2-like profile is present at 7 dpi and is well established by 28 dpi in this permissive host.

The effect of experimental gastric dilatation-volvulus on adenosine triphosphate content and conductance of the canine gastric and jejunal mucosa.

The objective of this study was to determine if experimental gastric dilatation volvulus (GDV) would decrease adenosine triphosphate (ATP) concentration and increase membrane conductance of the canine gastric and jejunal mucosa. Male dogs (n = 15) weighing between 20 and 30 kg were used. Dogs were randomly assigned to 1 of 3 equal groups: Group 1 was control, group 2 was GDV, and group 3 was ischemia. All dogs were anesthetized for 210 min. Group 1 had no manipulation. Group 2 had GDV experimentally induced for 120 min followed by decompression, derotation, and reperfusion for 90 min. Group 3 had GDV experimentally induced for 210 min. Gastric (fundus and pylorus) and jejunal tissue was taken at 0, 120, and 210 min from all of the dogs. Tissue was analyzed for ATP concentration, mucosal conductance, and microscopic changes. The ATP concentration in the fundus did not change significantly from baseline in group 2, but decreased significantly below baseline at 210 min in group 3. The ATP concentration in the jejunum decreased significantly below baseline in groups 2 and 3 at 120 min, remaining significantly decreased in group 3 but returning to baseline at 210 min in group 2. Mucosal conductance of the fundus did not change significantly in any dog. Mucosal conductance of the jejunum increased at 120 min in groups 2 and 3, and became significantly increased above baseline at 210 min. The jejunal mucosa showed more profound cellular changes than the gastric mucosa. The jejunum showed substantial decreases in ATP concentration with an increase in mucosal conductance, suggesting cell membrane dysfunction. Dogs sustaining a GDV are likely to have a change in the activity of mucosal cells in the jejunum, which may be important in the pathophysiology of GDV.

Effect of Eucommia ulmoides on systolic blood pressure in the spontaneous hypertensive rat.

Experiments were conducted to establish the safety and efficacy of Eucommia ulmoides (Du-Zhong) extract in the treatment of hypertension. Pilot experiments using rats demonstrated that E. ulmoides extract was safe to the saturation limits of the compound. The maximum tolerated dose (MTD) was 1200 mg/kg when administered by gastric gavage at a concentration of 1200 mg/ml. Also, rats given 200 mg/kg, 600 mg/kg or 1200 mg/kg doses of E. ulmoides extract daily for 28 days demonstrated no evidence of acute toxicity as determined by clinical appearance, histopathology and serum chemistry evaluation. Lastly, spontaneous hypertensive rats (SHRs) were administered E. ulmoides extract daily for 22 days. Systolic blood pressure (BP) was measured on treatment days 1, 8, 15 and 22 at 0, 1, 2 and 3 hours post-treatment. Beginning on day 8, E. ulmoides extract administered at the mid or high dosages lowered BP in male, but not female, rats. BP declined at a rate of approximately 10 mmHg per hour. The mid dosage of 600 mg/kg was found to be the minimum effective dose. In conclusion, E. ulmoides extract was non-toxic and effective in reducing systolic BP in the SHR.

Trauma-induced aneurysmal bone cysts in two psittacine species (Cacatua alba and Nymphicus hollandicus).

An umbrella cockatoo (Cacatua alba) and two cockatiels (Nymphicus hollandicus) were presented with rapidly enlarging masses of the head or wing joints. Historic trauma to these areas was confirmed in two cases. All birds were >2 yr of age, and two were female. Cytologic examination of fluid aspirated from masses in two cases was described as serosanguineous cytologically but failed to reveal inflammation, neoplasia, or microorganisms. Radiographic evaluation of these masses included proliferation and lysis of bone, suggestive of a neoplastic process. Histopathologic examination of surgically excised tissues revealed proliferative new bone and an absence of neoplastic tissue in all cases, consistent with aneurysmal bone cyst formation. Despite the guarded prognosis reported for other companion animals, these case results suggest a good prognosis for aneurysmal bone cyst in psittaciformes. Complete surgical excision and histopathologic examination is recommended for definitive diagnoses of aneurysmal bone cyst. Postoperative bandaging and rational antibiotic use are indicated to prevent excessive motion and secondary infection of affected sites, respectively.