Neuronal maturation in the hippocampal dentate gyrus via chronic oral administration of Artemisa annua extract is independent of cyclooxygenase 2 signaling pathway in diet-induced obesity mouse model.

Recently, we reported that Artemisia annua (AA) has anti-adipogenic properties in vitro and in vivo. Reduction of adipogenesis by AA treatment may dampen systemic inflammation and protect neurons from cytokine-induced damage. Therefore, the present study was undertaken to assess whether AA increases neuronal maturation by reducing inflammatory responses, such as those mediated by cyclooxygenase 2 (COX-2). Mice were fed normal chow or a high-fat diet with or without chronic daily oral administration of AA extract (0.2 g/10 mL/kg) for 4 weeks; then, changes in their hippocampal dentate gyri were measured via immunohistochemistry/immunofluorescence staining for bromodexoxyuridine, doublecortin, and neuronal nuclei, markers of neuronal maturation, and quantitative western blotting for COX-2 and Iba-1, in order to assess correlations between systemic inflammation (interleukin-6) and food type. Additionally, we tested the effect of AA in an Alzheimer's disease model of Caenorhabditis elegans and uncovered a potential benefit. The results show that chronic AA dosing significantly increases neuronal maturation, particularly in the high-fat diet group. This effect was seen in the absence of any changes in COX-2 levels in mice given the same type of food, pointing to the possibility of alternate anti-inflammatory pathways in the stimulation of neurogenesis and neuro-maturation in a background of obesity.

Localization of ghrelin and its receptor in the reproductive tract of Holstein heifers.

The aim of this experiment was to localize the mRNA and protein of ghrelin and its active receptor, growth hormone secretagogue 1A (GHS-R1A), within the reproductive tract of dairy cattle. Ghrelin is an orexigenic hormone that has been identified as a potent regulator of energy homeostasis. Recent evidence suggests that ghrelin may also serve as a metabolic signal to the reproductive tract. Ghrelin and GHS-R1A have been identified in the reproductive tract of several species, including humans, mice, and rats. However, ghrelin and GHS-R1A expression have not been described within bovine reproductive tissues. Therefore, the ampulla, isthmus, uterine body, corpus luteum, and follicles were harvested from 3 Holstein heifers (15.91±0.07 mo of age) immediately following exsanguination. Duodenum and hypothalamus were collected as positive controls for ghrelin and GHS-R1A, respectively. Tissues were fixed in 10% formalin and embedded in paraffin for microscopy. Additional samples were stored at -80°C for detection of mRNA. Ghrelin and GHS-R1A mRNA and protein were observed in all tissue types within the reproductive tract of dairy heifers; however, expression appeared to be cell specific. Furthermore, ghrelin protein appeared to be localized to the cytoplasm, whereas GHS-R1A protein was found on the plasma membrane. Within the reproductive tissues, ghrelin mRNA and protein were most abundantly expressed in the ampulla of the oviduct. Concentrations of GHS-R1A were lower than those of ghrelin but differed between tissues. This is one of the first studies to provide molecular evidence for the presence of ghrelin and GHS-R1A within the entire reproductive tract. However, implications for fertility remain to be determined.

Evaluation of antibiotics for treatment of cattle infected with Leptospira borgpetersenii serovar hardjo.

OBJECTIVE: To evaluate antibiotics for treatment of cattle with leptospirosis caused by Leptospira borgpetersenii serovar hardjo. DESIGN: Randomized controlled trial. ANIMALS: 42 healthy mixed-breed cattle. PROCEDURE: Cattle were inoculated via conjunctival instillation with L. borgpetersenii serovar hardjo. After infection and urinary shedding of L. borgpetersenii were confirmed, cattle were treated with various antibiotics. To determine effectiveness of antibiotic treatment, urinary shedding of L. borgpetersenii was monitored for 4 to 6 weeks after administration of antibiotics, using darkfield microscopic examination, microbial culture, immunofluorescence testing, and a polymerase chain reaction assay. RESULTS: All inoculated cattle developed leptospirosis and shed leptospires in their urine. The following antibiotic treatments resulted in elimination of urinary shedding of leptospires: a single injection of oxytetracycline (20 mg/kg 19 mg/lb] of body weight, IM), tilmicosin (10 mg/kg [4.5 mg/lb], SC), or a combination product that contained dihydrostreptomycin-penicillin G (25 mg/kg [11.4 mg/lb], IM) or multiple injections of ceftiofur sodium (2.2 or 5 mg/kg [1 or 2.3 mg/lb], IM, once daily for 5 days, or 20 mg/kg, IM, once daily for 3 days). CONCLUSIONS AND CLINICAL RELEVANCE: Successful resolution of leptospirosis in cattle by administration of dihydrostreptomycin-penicillin G confirms results obtained by other investigators. Three other antibiotics (oxytetracycline, tilmicosin, and ceftiofur) also were effective for resolving leptospirosis and may be useful substitutes for dihydrostreptomycin, an antibiotic that is no longer available for use in food-producing animals in the United States. Cost, safety, and withdrawal times of these various treatment options need to be considered.

Leptospira infection in two black rhinoceroses (Diceros bicornis michaeli).

Two black rhinoceroses (Diceros bicornis michaeli) developed clinical leptospirosis without hemolytic crises. The first rhinoceros presented with peracute depression, anorexia, rear leg trembling, dysuria, glucosuria, gastrointestinal discomfort, and decreased fecal output and died within 12 hr. Necropsy and histopathology revealed lesions within multiple organs. Leptospirosis was diagnosed postmortem based on positive fluorescent antibody staining of liver. The second rhinoceros presented 2 mo later with similar signs. It survived with treatment and was diagnosed with leptospirosis based on serology using microscopic agglutination testing and detection of urinary antigen using a fluorescent antibody technique. Leptospira kirschneri serovar grippotyphosa was postulated as the etiologic agent, with transmission probably occurring through wallow contamination by wild raccoons (Procyon lotor).

Identification of a dog IgD-like molecule by a monoclonal antibody.

IgD has not been identified in dogs. We produced a monoclonal antibody (mAb) designated 9B during the production of hybridomas to dog IgE. Using Western blot analysis under non-reducing conditions, the mAb (9B) recognized a predominant protein band of 185 kDa which was also recognized by anti-dog IgG F(ab')2, suggesting that this 185 kDa protein is an immunoglobulin (Ig) containing light chains. Under reducing conditions, the mAb (9B) recognized only one protein band of 55 kDa which presented a distinct molecular weight (MW) and immunoreactivity from the dog tau, mu, alpha, and epsilon chains. The 55 kDa band did not react with anti-dog IgE, IgM, IgA, and IgG, but did react with the mAb (9B). The MW was 75 kDa for the epsilon chain, 77.5 kDa for the mu chain, 58 kDa for the alpha chain, and 52 kDa for the tau chain. Further, by immunofluorescent staining, this Ig recognized by the mAb (9B) was found on the surface of dog lymphocytes. Studies of this dog Ig with the mAb revealed that this Ig bound to protein A and protein G-Sepharose, and that its enzyme-linked immunosorbent assay (ELISA) activity as measured by the mAb (9B) did not change after heating at 56 degrees C for 2 h. Ragweed-specific IgG, IgE, and this newly defined Ig significantly increased when dogs were immunized with ragweed extract. These data suggest that this Ig is a previously unrecognized IgD-like molecule in dogs.

A study by flow cytometry of lymphocytes in sow colostrum.

Mammary secretions contain leucocytes which may be of value to the neonate. The cells obtained from sow colostrum (1 to 2.5 x 10(6) ml-1) are mainly lymphocytes (10 to 25 per cent) and epithelial cells (more than 20 per cent). In milk, there are few lymphocytes (0.5 to 2 per cent) and mostly alveolar epithelial cells. The study of lymphocytes in the mammary secretions of sows has been made difficult by the high proportion of epithelial cells, which could not be separated from lymphocytes, and by a high background in membrane immunofluorescence labelling. This paper describes a method for the study of the cells in the mammary secretions of sows by flow cytometry. It showed that 70 to 90 per cent of colostral lymphocytes were T lymphocytes, with T8 lymphocytes predominating over T4, and that the ratio T4/T8 was significantly lower in colostrum (0.57) than in blood (0.80). There were no lymphocytes expressing interleukin-2-receptors in the colostrum of sows.

Influences of extracellular matrix components on the growth and differentiation of ruminal epithelial cells in primary culture.

Primary cultures of ovine ruminal epithelial cells were made to study the influence of collagen types I and IV out of medium supplementation with various hormones and Na-n-butyrate on cell morphology and growth characteristics. Both collagen type I and type IV led to increased cell proliferation with the stimulatory effect being more pronounced in collagen IV. In cultures grown on collagen I, both non-stratified and stratified colonies were found, whereas cultures grown on collagen IV showed predominantly stratified growth. Cells in both stratified and non-stratified colonies were positive for cytokeratin antibody. In non-stratified colonies, positive staining with fibronectin antibodies (FN-15) was found in a network over and around the cells. It is suggested that the non-stratified ruminal epithelial cells are in some respects similar to a 'non-differentiating keratinocyte' strain, derived from newborn foreskin epidermis. Cells in stratified colonies bound Ulex europaeus (UEAI) lectin which has been shown to be specific for differentiated epithelial cells in ruminal mucosa. Supplementation of culture medium with glucagon and insulin increased the total cell-overgrown area of collagen I cultures, whereas this effect was absent in cultures grown on collagen IV. In both cultures grown on collagen I or IV, hydrocortisone led to an increase in total cell-overgrown area, whereas Na-n-butyrate inhibited proliferation.