Cytopathology of the central nervous system. Part I. Utility of crush smear cytology in intraoperative diagnosis of central nervous system lesions

OBJECTIVE: To evaluate the utility of rapid intraoperative crush smear cytologic diagnosis of central and peripheral nervous system lesions and to determine the accuracy and relevance of the accuracy of the intraoperative cytologic diagnosis when compared to the final paraffin section diagnosis. STUDY DESIGN: The crush (squash) smear technique was introduced at Sher-i-Kashmir Institute of Medical Sciences in May 2003. The 8 months of 2003 were used for standardization of the procedure. In 2004, 151 patients with open neurosurgical specimens or stereotactic biopsies were diagnosed intraoperatively by crush smears, and the diagnosis was compared with final diagnosis on paraffin sections of the same tissue samples. No supplementation of frozen sections was used. RESULTS: Of 151 cases, 144 were diagnosed accurately intraoperatively by crush smear cytology when compared with the respective paraffin section diagnoses. The diagnostic accuracy attained was 95.36%. Each case was diagnosed within 10 minutes after receipt of sample. Neurosurgical procedure (open or stereotaxy) did not affect diagnostic accuracy. CONCLUSION: In the expert hands of a pathologist with good exposure neurosurgical specimens, crush smear cytology is an accura and reliable procedure for the intraoperative diagnosis central nervous system tumors.     

Integrating the costs of plant toxins and predation risk in foraging decisions of a mammalian herbivore

Foraging herbivores must satisfy their nutrient requirements in a world of toxic plants while also avoiding predators. Plant toxins and perceived predation risk at food patches should both reduce patch residency time, but the relative strengths of these factors on feeding decisions has rarely been quantified. Using an arboreal generalist herbivore, the common brushtail possum Trichosurus vulpecula, we tested the effects on food intake of the plant toxin, cineole, and regurgitated pellets from one of its predators, the powerful owl Ninox strenua at the small spatial scale of the food patch. We used the giving-up density (GUD) framework, with animals harvesting food items (sultanas) in an inedible matrix (small pebbles). We ran two consecutive field experiments in a eucalypt woodland in eastern Australia, 1 month apart in the same location. In experiment 1, there was a significant interaction between cineole [at 17% of dry matter (DM)] and owl pellets. The GUD was lowest in the absence of both cineole and owl pellet, intermediate in the presence of owl pellet; and highest with cineole ± owl pellet. The effect of owl pellet diminished over time. In experiment 2, only cineole (at 10% DM) increased the GUD significantly. The difference in effect of owl pellet was probably due to both habituation and freshness of the cue. Our study demonstrates the importance of synthesising predator–prey and plant–herbivore ecology to better understand the complex set of constraints influencing foraging herbivores. The greater effect of toxin than fear on possums is likely to be due to its high, but ecologically relevant concentration. This highlights the need to explore the relative and net impacts of a range of concentrations of plant toxins and predation risks.     

Heavy Metal Phytotoxicity to Radish (Raphanus sativus L.) in a Digested Sludge-amended Gangetic Alluvium

A limiting factor in land application of sewage sludge is the resultant heavy metal accumulation in soils followed by biomagnification in the food chain, posing a potential hazard to animal and human health. In view of this fact, pot experiments were conducted to evaluate the effect of digested sludge application to soil on phytotoxicity of heavy metals such as Cd, Cr, Ni, and Pb to radish (Raphanus sativus L.) plants. Increasing sludge levels resulted in increased levels of DTPA-extractable heavy metals in the soil. Cadmium was the dominant metal extracted by DTPA followed by Ni, Pb, and Cr. The extractability of metals by DTPA tended to decrease from the first to the second crop. Dry matter yield of radish increased significantly as a function of increasing sludge treatments. Soil application of sludge raised the concentration of one or more heavy metals in plants. Shoots contained higher concentrations of Cd, Cr, and Ni than the roots of radish plants. Shoot concentrations of Cd, Cr, Ni, and Pb were within the tolerance levels of this crop at all rates of sludge application. Shoot as well as root concentration of Cd was above 0.5 mg kg^?1, considered toxic for human and animal consumption. The levels of DTPA-extractable Cd and Ni were less correlated while those of Cr and Pb were more correlated with their respective shoot and root contents. The results emphasize that accumulation of potentially toxic heavy metals in soil and their build-up in vegetable crops should not be ignored when sludge is applied as an amendment to land.     

Abnormalities in Osteoclastogenesis and Decreased Tumorigenesis in Mice Deficient for Ovarian Cancer G Protein-Coupled Receptor 1

Ovarian cancer G protein-coupled receptor 1 (OGR1) has been shown to be a proton sensing receptor in vitro. We have shown that OGR1 functions as a tumor metastasis suppressor gene when it is over-expressed in human prostate cancer cells in vivo. To examine the physiological functions of OGR1, we generated conditional OGR1 deficient mice by homologous recombination. OGR1 deficient mice were viable and upon gross-inspection appeared normal. Consistent with in vitro studies showing that OGR1 is involved in osteoclastogenesis, reduced osteoclasts were detected in OGR1 deficient mice. A pH-dependent osteoclasts survival effect was also observed. However, overall abnormality in the bones of these animals was not observed. In addition, melanoma cell tumorigenesis was significantly inhibited in OGR1 deficient mice. OGR1 deficient mice in the mixed background produced significantly less peritoneal macrophages when stimulated with thioglycolate. These macrophages also showed altered extracellular signal-regulated kinases (ERK) activation and nitric oxide (NO) production in response to lipopolysaccharide. OGR1-dependent pH responses assessed by cAMP production and cell survival in macrophages or brown fat cells were not observed, presumably due to the presence of other proton sensing receptors in these cells. Our results indicate that OGR1''s role in osteoclastogenesis is not strong enough to affect overall bone development and its role in tumorigenesis warrants further investigation. The mice generated can be potentially used for several disease models, including cancers or osteoclast-related diseases.     

Novel,potent and selective cyclin D1/CDK4 inhibitors: indolo[6,7-a]pyrrolo[3,4-c]carbazoles

The synthesis and CDK inhibitory properties of a series of indolo[6,7-a]pyrrolo[3,4-c]carbazoles is reported. In addition to their potent CDK activity, the compounds display antiproliferative activity against two human cancer cell lines. These inhibitors also effect strong G1 arrest in these cell lines and inhibit Rb phosphorylation at Ser780 consistent with inhibition of cyclin D1/CDK4.     

Biochemical effects of Nigella sativa L seeds in diabetic rats

Oral administration of ethanol extract of N. sativa seeds (300 mg/kg body weight/day) to streptozotocin induced diabetic rats for 30 days significantly reduced the elevated levels of blood glucose, lipids, plasma insulin and improved altered levels of lipid peroxidation products (TBARS and hydroperoxides) and antioxidant enzymes like catalase, superoxide dismutase, reduced glutathione and glutathione peroxidase in liver and kidney. The results confirm the antidiabetic activity of N. sativa seeds extract and suggest that because of its antioxidant effects its administration may be useful in controlling the diabetic complications in experimental diabetic rats.