Amelioration of caudal thoracic syringohydromyelia following surgical management of an adjacent arachnoid cyst

A nine-year-old male, neutered, pug was presented for investigation of progressive ambulatory paraparesis and pelvic limb ataxia of three months' duration. Magnetic resonance imaging was suggestive of caudal thoracic syringohydromyelia with an adjacent intradural arachnoid cyst. The cyst was marsupialised following dorsal laminectomy. Neurological status had improved 10 weeks following surgery when repeat magnetic resonance imaging revealed reduced spinal cord compression both as a result of resolution of the cyst and reduction in size of the syringohydromyelia. At 17 months following surgery, the dog showed further improvements in neurological status, exhibiting mild pelvic limb ataxia and proprioceptive deficits. Improved cerebrospinal fluid flow following surgery may have played a role in the improvement in both conditions. The presence of syringohydromyelia in this context does not preclude a favourable clinical outcome following surgical management.     

Nitrogen fixation in termites

Nitrogen fixation, measured by the reduction of acetylene to ethylene, was found in workers of the dry-wood termite Kalotermes minor. The soldiers and reproductive castes fixed little or no nitrogen. The fixation rates ranged between 24 and 566 micrograms of nitrogen fixed per month per gram (wet weight) of termite. Nitrogen fixation can be a significant source of nitrogen for these termites.     

Der Einfluß von Systox auf einige Insektenarten des Zuckerrübenfeldesvon Systox auf einige Insektenarten des Zuckerrübenfeldes

Ohne Zusammenfassung     

Tumor cell rejection through terminal cell differentiation

Leukemic cells cultured in the presence of various conditioned media differentiate into macrophages. This finding suggested that the maintenance of undifferentiated state and self-renewal in vivo may be related to the inability of the host to generate an appropriate level of differentiation factor (DF). Evidence for this hypothesis was derived from experiments in vitro and in vivo with myeloid leukemia of rat. The following results were obtained: (i) in vitro, the percentage of cell differentiation at a fixed concentration of DF was inversely related to the concentration of cells; (ii) leukemic cell inoculates that were lethal to 7-day-old rats were rejected by 21-day-old rats; (iii) leukemic cells in diffusion chambers underwent differentiation in 21-day-old rats but not in 7-day-old rats; (iv) organs from 21-day-old rats contained more DF activity than those of 7-day-old rats; (v) treatment of rats with DF in diffusion chambers resulted in leukemic cell differentiation inside the chamber; and (vi) the development of leukemia in 7-day-old rats was aborted by treatment with DF. These results show that the differentiation of rat leukemia cells requires the appropriate level of DF. The proliferation of transplanted leukemia cells in 7-day-old rats goes unchecked because of inadequate generation of DF. Conversely, in the 21-day-old rats, rejection is accomplished by differentiation of the transplanted cells.     

Simple Phenolic Acids in Flours Prepared from Canadian Wheat: Relationship to Ash Content,Color, and Polyphenol Oxidase Activity

Simple phenolic acid levels were determined on pooled millstreams of five different classes of Canadian wheat milled to ~75, 80, and 85% extraction. Pooled flours and whole grain were analyzed by reversed-phase high-performance liquid chromatography (RP-HPLC) to establish endogenous levels of insoluble bound, soluble esterified, and free phenolic acids. Only ferulic acid was detected in the insoluble bound category, which accounted for >80% of the total phenolic acids present in every flour. The soluble esterified phenolic acids accounted for up to 17% of the overall total phenolic acid content within a flour. The major constituents were sinapic, ferulic, and vanillic acids, with minor amounts of coumaric, caffeic, and syringic acids. Free phenolic acids accounted for a maximum of 6% of the total phenolic content of any prepared flour. Ferulic acid was the major free phenolic acid, while sinapic acid was not detected in any flour. Significant correlations (r = 0.64–0.97, P < 0.05) were observed between insoluble bound ferulic acid, individual soluble esterified acids, and most free acids with polyphenol oxidase activity, as well as color and ash content for each class.     

A predator unmasked: life cycle of Bdellovibrio bacteriovorus from a genomic perspective

Predatory bacteria remain molecularly enigmatic, despite their presence in many microbial communities. Here we report the complete genome of Bdellovibrio bacteriovorus HD100, a predatory Gram-negative bacterium that invades and consumes other Gram-negative bacteria. Its surprisingly large genome shows no evidence of recent gene transfer from its prey. A plethora of paralogous gene families coding for enzymes, such as hydrolases and transporters, are used throughout the life cycle of B. bacteriovorus for prey entry, prey killing, and the uptake of complex molecules.     

MAGNETIC RESONANCE IMAGING FEATURES OF INTRACRANIAL GRANULAR CELL TUMORS IN SIX DOGS

Magnetic resonance (MR) imaging characteristics of intracranial granular cell tumors (GCTs) have been previously reported in three dogs. The goal of this retrospective study was to examine a larger number of dogs and determine whether distinctive MR characteristics of intracranial GCTs could be identified. Six dogs with histologically confirmed intracranial GCTs and MR imaging were included. Tumor location, size, mass effect, T1‐ and T2‐weighted signal intensity, and peritumoral edema MR characteristics were recorded. In all dogs, GCTs appeared as well‐defined, extra‐axial masses with a plaque‐form, sessile distribution involving the meninges. All tumors were located along the convexity of the cerebrum, the falx cerebri, or the ventral floor of the cranial vault. All tumors were mildly hyperintense on T1‐weighted images, and iso‐ to hyperintense on T2‐weighted images. A moderate‐to‐severe degree of peritumoral edema and mass effect were evident in all dogs. Findings indicated that, while several MR imaging characteristics were consistently identified in canine cerebral GCTs, none of these characteristics were unique or distinctive for this tumor type alone.