Determination of platinum by neutron activation analysis in nerve tissue from rats treated with cisplatin

Biological Trace Element Research - The analytical method used for the determination of traces of platinum and gold in different tissues of Wistar rats is based on neutron activation analysis with...     

Iron Deficiency Alters Discrete Proteins in Rat Caudate Nucleus and Nucleus Accumbens

Young rats (21 days old) made nutritionally iron deficient, by feeding them a semisynthetic diet containing skimmed milk for 5 weeks, had significantly lowered hemoglobin levels (5.2 +/- 4 g/100 ml). The nonheme iron content in caudate nucleus was decreased by 47%. The behavioral response of iron-deficient rats to apomorphine (2 mg/kg) and the density of 3,4-dihydroxyphenylethylamine (dopamine) D2 receptors, as measured by [3H]spiperone binding in caudate nucleus, were significantly reduced by 70 and 53%, respectively. The possibility that nutritional iron deficiency may affect protein content in brain was investigated by measuring the apparent concentration of proteins in caudate nucleus and nucleus accumbens from iron-deficient and control animals using two-dimensional gel electrophoresis. The data indicate that iron deficiency can affect content in these two brain regions. Significant changes in the content of 10 proteins were noted in the caudate nucleus and nucleus accumbens in iron-deficient rats. The albumin level was significantly increased in both regions studied, whereas the neuron-specific enolase level was increased in the nucleus accumbens and the glial fibrillary acidic protein level was reduced in the caudate nucleus. The significance of these protein content changes, as well as a reduction in content of a 94-kilodalton protein (a molecular size similar to that of the D2 dopamine receptor), remains to be established.     

Alteration of surfactant protein A expression in renal cell carcinoma

Surfactant protein-A (SP-A) belongs to a family of collagen-containing C-type lectins called collectins. SP-A is expressed by renal tubule epithelial cells. We investigated the distribution of SP-A in renal cell carcinomas (RCC) using immunohistochemical techniques and western blotting. We used 35 formalin fixed, paraffin embedded (FFPE) RCC tissue samples. We compared results with clinico-pathological parameters of RCC including age, sex, Fuhrman grade, tumor volume, tumor node metastasis (TNM) and clinical stage. SP-A was localized in the glomerulus and renal tubule epithelium in nontumor tissue and strong SP-A immunoreactivity was observed in tumor tissue. SP-A was expressed in the RCC tumor cells (64%) and nontumor cells (34%) in males and RCC tumor cells (90%) and nontumor cells (30%) in females. There was a significant correlation between SP-A immunoreactivity in tumor cells and gender, age, tumor diameter, Fuhrman grade and tumor diameter. Western blot analysis supported the immunohistochemical findings. We present evidence for involvement of SP-A in RCC and suggest that increased SP-A expression in RCC is associated with favorable prognosis.     

Palatability and feeding preferences of Uresiphita maorialis (Lepidoptera: Crambidae) for three Sophora species

In a three-hour bioassay, we tested the palatability and feeding preferences of Uresiphita maorialis (kōwhai moth) for Sophora tetraptera, Sophora microphylla and Sophora prostrata. Palatability tests showed no differences among the Sophora species. Feeding preferences, on the other hand, showed that S. tetraptera and S. microphylla leaves are preferred over S. prostrata leaves. Our results support our field observations in Wellington city parks and gardens showing that S. tetraptera and S. microphylla plants frequently have higher densities of larvae than S. prostrata.     

Long‐term rearing affects pheromone‐mediated flight behaviour of the Indian meal moth,Plodia interpunctella

The pest Plodia interpunctella (Hübner) is reared in many research laboratories. In a culture established in 1996, attraction of males to the female‐produced sex pheromone in flight tunnel assays gradually decreased after ≈15 years of rearing. A new culture was established to enable comparison with the old culture regarding traits associated with mate finding. Female calling activity, pheromone titre and male antennal response to pheromone components did not differ between cultures. In contrast, very few males from the old culture reached the pheromone source in flight tunnel assays compared with 61%–81% of males from the other culture. Our results highlight the importance of maintaining viable insect cultures for research purposes and suggest frequent evaluation of traits involved in chemical communication in such cultures to ensure reliable results in experiments.     

Role of area postrema in control of torpor in Siberian hamsters

Siberian hamsters undergo torpor during the short days of winter and in response to glucoprivation or food restriction. We tested whether the area postrema and the adjacent nucleus of the solitary tract (hereafter the AP), which monitor metabolic fuel availability, also control the onset of torpor. Siberian hamsters that had manifested torpor spontaneously or had entered torpor in response to 2-deoxy-D-glucose (2-DG) treatment were subjected to area postrema ablations (APx). Hamsters continued to display torpor postoperatively; most features of torpor were unaffected by APx. The AP is not necessary for expression of torpor elicited by short day lengths or metabolic challenge. In contrast, decreases in food intake manifested by hamsters treated with 2-DG were counteracted by APx. In Siberian hamsters, the AP appears to mediate effects of 2-DG on food intake but not torpor.     

Effect of unilateral and bilateral resistance exercise on maximal voluntary strength,total volume of load lifted,and perceptual and metabolic responses

The present study investigated the effect of unilateral and bilateral resistance exercise (RE) on maximal voluntary strength, total volume of load lifted (TVLL), rating of perceived exertion (RPE) and blood lactate concentration of resistance-trained males. Twelve healthy men were assessed for the leg extension one-repetition maximum (1RM) strength using bilateral and unilateral contractions. Following this assessment, an RE session (3 sets of repetitions to failure) was conducted with bilateral and unilateral (both limbs) contractions using a load of 50% 1RM. The TVLL was calculated by the product of the number of repetitions and the load lifted per repetition. RPE and blood lactate were measured before, during and after each set. Session RPE was measured 30 minutes after RE sessions. There was a significant difference in the bilateral (120.0±11.9) and unilateral (135.0±20.2 kg) 1RM strength (p < 0.05). The TVLL was similar between both RE sessions. Although the repetitions decreased with each successive set, the total number of repetitions completed in the bilateral protocol (48) was superior to the unilateral (40) protocol (p < 0.05). In both bouts, RPE increased with each subsequent set whilst blood lactate increased after set 1 and thereafter remained stable (p < 0.05). The RPE and lactate responses were not significantly different between both sessions. In conclusion, a bilateral deficit in leg extension strength was confirmed, but the TVLL was similar between both RE sessions when exercising to voluntary fatigue. This outcome could be attributed to the number of repetitions completed in the unilateral RE bout. The equal TVLL would also explain the similar perceptual and metabolic responses across each RE session.