Vincristine Therapy for Mast Cell Tumors in Dogs

Twenty-seven dogs with naturally occurring mast cell tumors were treated with weekly IV injections of vincristine (0.75 mg/m²) for 4 treatments. Two dogs (7%) had a partial response. Nine dogs (32%) had treatment stopped prematurely because of toxicity or a perceived deterioration in their quality of life. We conclude that vincristine is ineffective as a sole treatment for measurable mast cell tumors in dogs and produces an undesirable number of adverse reactions.     

Comparison of faecal culture and IS900 PCR assay for the detection of <Emphasis Type="Italic">Mycobacterium avium</Emphasis> subsp. <Emphasis Type="Italic">paratuberculosis</Emphasis> in bovine faecal samples

Comparative efficacy of faecal culture and IS900 Polymerase chain reaction (PCR) assay of faecal samples was investigated in 40 clinically suspected cases of Johne’s disease in dairy cattle. The sensitivity of faecal culture and PCR assay in this study was 52.5% (21/40) and 90% (36/40) respectively. All isolates appeared only on the mycobactin J supplemented Herrold’s egg yolk medium (HEYM) at 8–16 weeks post-inoculation, were acid-fast and were positive for IS900 PCR yielding a single amplicon of 217 bp. A total of 28 faecal samples out of 40 were positive by IS900 primary PCR assay for Mycobacterium avium subsp. paratuberculosis (Map) yielding an expected product of size 217 bp. Twelve faecal samples, which gave negative results in the primary PCR, were subjected to secondary PCR assay. Of the 12 samples, 8 gave positive results in the IS900 nested PCR (nPCR), which yielded a PCR product of 167 bp, proving better sensitivity of nPCR assay than single amplification PCR. PCR could detect additionally 15 samples as positive which were negative by faecal culture. The chi-square analysis showed a highly significant difference between the tests (P< 0.01). This study suggests that IS900-PCR-based detection of Map could be used as a potential diagnostic tool for rapid and effective Johne’s disease surveillance.     

Porcine circovirus-2 DNA concentration distinguishes wasting from nonwasting pigs and is correlated with lesion distribution, severity, and nucleocapsid staining intensity.

The emergence of severe porcine circoviral disease in North America is associated with Porcine circovirus-2 genotype b (PCV-2b), which has led to speculation that PCV-2b is more virulent than PCV-2a. The objectives of this study were to 1) correlate the PCV-2 DNA concentration and lesions in wasting (WST) and age-matched healthy (HLTH) pigs from 2 clinically affected farms, and unaffected (UNFCT) pigs from a farm with no prior clinical or diagnostic history of PCVD; and 2) to determine the initial estimates of sensitivity and specificity of PCV-2 quantitative polymerase chain reaction (qPCR). PCV-2b was confirmed in all 3 farms. Compared with HLTH pigs, WST pigs demonstrated significantly more prevalent thymic atrophy, failure of normal pulmonary collapse, and ascites (P < 0.017 for all). The HLTH and UNFCT pigs had significantly more pronounced lymphoid germinal centers and proliferative paracortical T-dependent zones, compared with WST pigs (P < 0.017). Across all tissues, PCV-2 DNA concentrations were significantly higher in WST compared with HLTH and UNFCT pigs (P < 0.017 for all). The PCV-2 DNA concentrations were strongly correlated with PCV-2 nucleocapsid staining intensity in lymph node, spleen, Peyer's patches, lung, liver, and kidney (0.60 < or = r < or = 0.84). In the current study, the PCV-2 DNA log10 cutoff concentrations best able to distinguish WST from HLTH and UNFCT pigs were between 7.0 and 8.0 per gram for tissues, and between 4.0 and 5.0 per milliliter for sera. The presence of PCV-2b in UNFCT pigs is evidence that PCV-2b by itself is not sufficient to induce severe disease.     

Resistance to bean common mosaic potyvirus strains and its inheritance in some Indian land races of common bean

Evaluation of 397 common bean accessions of diverse origin revealed the presence of effective sources of resistance against bean common mosaic potyvirus strains prevalent in Himachal Pradesh, a north-western Himalayan state of India. 21 accessions viz., KR 7, KR 225, KR 295, KRC 4, KRC 7, KRC 11, KRC 12, KRC 13, KRC 16, KRC 22, Amanda, Black Turtle Soup, Contender, Hans, Great Northern UI 123, Improved Tender Green 40031, Jubila, Kentucky wonder, Monroe, Premier and Sanilac, were found resistant to NL-1n and NL-7n strains. Some of the genotypes showed strain specific resistance. Pattern of inheritance studied in Hans, Contender, KRC 4 and KRC 22 of Indian origin against strain NL-1n revealed that single dominant gene governed the resistance in Hans and Contender whereas single recessive gene determined the resistance in KRC 22 and KRC 4. SCAR marker SW13₆₉₀ amplified a product of 690 bp in Hans and Contender, confirmed the presence of I gene in these cultivars. The implications of above genes in breeding for programme for BCMV resistance are discussed.     

REVIEW: Variability in Fine Structures of Noncellulosic Cell Wall Polysaccharides from Cereal Grains: Potential Importance in Human Health and Nutrition

Noncellulosic polysaccharides from the cell walls of cereal grains are not digested by human small intestinal enzymes and so contribute to total dietary fiber intake. These polysaccharides are becoming recognized increasingly for their potential to lower the risk of serious diet‐related conditions such as type II diabetes, cardiovascular disease, colorectal cancer, and diverticular disease. The effectiveness of noncellulosic cell wall polysaccharides in improving health outcomes is related to the fine structure and associated physicochemical properties. The two most nutritionally relevant wall polysaccharides of cereal grains are the arabinoxylans and the (1‐3,1‐4)‐β‐d ‐glucans. These polysaccharides have high molecular mass values but are nevertheless soluble in aqueous media, at least in part, where they adopt highly asymmetrical conformations and consequently form high viscosity solutions. Thus, arabinoxylans and (1‐3,1‐4)‐β‐d ‐glucans contribute to the soluble fiber component of human diets. The molecular size, solubility, and viscosity of the polysaccharides vary widely not only between different cereals but also within a single species. The variability in these properties reflects differences in the chemical structure of the polysaccharides, which in turn influences the beneficial effects of arabinoxylans and (1‐3,1‐4)‐β‐d ‐glucans in human diets. Here, we summarize information on the variability of fine structures of the arabinoxylans and (1‐3,1‐4)‐β‐d ‐glucans in common cereals and relate these to solubility, viscosity, and health benefits. The recent identification of genes involved in the biosynthesis of the (1‐3,1‐4)‐β‐d ‐glucans opens the way for the genetic improvement of cereal quality parameters that are important in human health.     

Benzothiadiazole induces the accumulation of phenolics and improves resistance to powdery mildew in strawberries

Benzothiadiazole (BTH) enhanced the accumulation of soluble and cell-wall-bound phenolics in strawberry leaves and also improved the resistance to powdery mildew infection under greenhouse conditions. The most pronounced change was seen in the levels of ellagitannins, which increased up to 2- to 6-fold 4 days after the BTH application, but persisted only in the inoculated plants. The induction of phenolic metabolism by BTH was also reflected in the fruits, several compounds being increased in inoculated, BTH-treated plants. Basal salicylic acid (SA) content was high in strawberry leaves, but increased in a similar fashion to other phenolics after the treatments. Several phenolic compounds were identified in strawberries for the first time. For example, ellagic acid deoxyhexose, three agrimoniin-like ellagitannins, sanguiin H-10- and lambertianin C-like ellagitannins in the leaves, ellagic acid, p-coumaric acid, gallic acid, and kaempferol hexose in the cell-wall-bound fraction of the leaves, and kaempferol malonylglucoside in the fruits. The findings show that BTH can enhance the accumulation of phenolics in strawberry plants which may then be involved in the BTH-induced resistance to powdery mildew.     

O-glycosylated cell wall proteins are essential in root hair growth

Root hairs are single cells that develop by tip growth and are specialized in the absorption of nutrients. Their cell walls are composed of polysaccharides and hydroxyproline-rich glycoproteins (HRGPs) that include extensins (EXTs) and arabinogalactan-proteins (AGPs). Proline hydroxylation, an early posttranslational modification of HRGPs that is catalyzed by prolyl 4-hydroxylases (P4Hs), defines the subsequent O-glycosylation sites in EXTs (which are mainly arabinosylated) and AGPs (which are mainly arabinogalactosylated). We explored the biological function of P4Hs, arabinosyltransferases, and EXTs in root hair cell growth. Biochemical inhibition or genetic disruption resulted in the blockage of polarized growth in root hairs and reduced arabinosylation of EXTs. Our results demonstrate that correct O-glycosylation on EXTs is essential for cell-wall self-assembly and, hence, root hair elongation in Arabidopsis thaliana.     

Ethnobotanical investigations in the genus <Emphasis Type="Italic">Momordica</Emphasis> L. in the Southern Western Ghats of India

Western Ghats, one of the megadiversity hotspots, hold a rich treasure of diversity in Momordica L. comprising M. charantia var. muricata, M. charantia var. charantia, M. dioica and M. sahyadrica. Vernacular names of these species vary from place to place. Traditional uses of these species comprising food, medicinal and cosmetic, culinary preparations, vernacular names in local dialects and taboos and religious beliefs relating to their domestication and folk taxonomy are dealt with in this paper.