Microglia--performers of the 21st century.

At the frontier between immunology and neuroscience, microglia, the enigmatic macrophages of the brain, have generated, in recent years, increasing interest. In response to even minor pathological changes in the brain, these extremely versatile glial cells occasionally enter in an over-activating state and produce pro-inflammatory cytokines and free radicals, thereby contributing directly to neuroinflammation and various brain disorders. This review provides an analysis of the latest developments in the microglia field, considering the important new research that illustrate their involvement in brain related diseases.

Unusual renal carcinoma with a double component: case report and review of the literature.

The authors report a rare case of a 60-year-old man who had in his left kidney a tumor with two distinct components: a tubulo-papillary pattern and an extensive high-grade squamous cell carcinoma. The literature concerning this subject will be also reviewed.

Behavioral effects of corpus callosum transection and environmental enrichment in adult rats.

A common assumption about the corpus callosum transection (CCX) is that it only affects behaviors heavily relying on interhemispheric communication. However, cerebral laterality is ubiquitous across motor and perceptual, cognitive and emotional domains, and the corpus callosum is important for its establishment. Several recent studies showed that the partial denervation of the sensorimotor isocortex through CCX derepressed neural growth processes that were sensitive to motor demand (experience-dependent neural plasticity). We investigated whether the facilitatory effects of CCX on cortical neural plasticity, shaped by differential housing, extended beyond the motor domain. Adult rats were housed in enriched (EE), standard (SE) or impoverished environments (IE) for 10 weeks, that is, 2 weeks before they underwent CCX or sham surgery, and, then, 8 weeks throughout the experiments. After they recovered from surgery, the behavioral performance of rats was tested using open-field, spontaneous alternation in the T-maze, paw preference, Morris water maze, and tone fear conditioning. The results indicated that the effects of CCX and housing on open-field behavior were independent, with CCX increasing the time spent in the center of the field at the beginning of the observation (i.e., emotionality), and EE and IE increasing rearing (emotionality) and reducing teeth-chattering (habituation), respectively. CCX reduced the frequency of spontaneous alternation, denoting spatial working memory deficits, while housing did not influence this performance. Neither CCX, nor housing significantly affected paw preference lateralization, although CCX was associated with a leftward bias in paw preference. In the Morris water maze, housing had effects on spatial acquisition, while CCX reduced activity, without interfering with spatial memory. CCX did not influence tone fear conditioning, but context fear conditioning seemed to benefit from EE. We conclude that CCX in adult rats has subtle, but specific behavioral effects pertaining to emotionality, spatial working memory, and, possibly, aversively motivated exploration, and these effects are either independent or only peripherally interact with the effects of housing.

Signet-ring prostatic carcinoma. Case presentation and review of the literature.

The authors present the case of a 71 years old man with the histopathological diagnosis of a signet-ring prostatic carcinoma, examined in usual and special stains as PAS and mucicarmin. The literature, the clinical aspect, the microscopic features, and the pathogenesis concerning this subject are reviewed.

A behavioral and histological study of the effects of long-term exposure of adult rats to aluminum.

Aluminum (Al) has been etiologically and epidemiologically related to several neurologic conditions, including Alzheimer's disease (AD). The effects of Al long-term exposure were investigated to describe the associated behavioral and brain modifications. Adult rats were intraperitoneally injected three times a week for 6 months with ecological doses of Al gluconate (0.85 mg/kg). The Al overload was confirmed by the significantly increased level of Al in serum. We assessed fear conditioning, spatial memory and emotional reactivity by shuttle-box task, Morris water maze, and open-field, respectively. The performance of the experimental animals at the shuttle-box task was significantly lower (p <.01) compared to that of control. The experimental animals had impaired spatial memory, with lower and more fluctuant performance at Morris water maze. The noxious-driven behavior of the experimental animals was also altered, with significantly lower activity scores (p <.05), and high emotionality scores (p <.01) at the open-field. We recovered and processed the brain for aluminum and amyloid deposits. The brains of experimental animals, studied by optical microscopy, displayed a massive cellular depletion in the hippocampal formation, particularly, the CAl field, and also in the temporal and parietal cortex. We observed numerous ghost-like neurons with cytoplasmic and nuclear vacuolations, and with Al deposits. The hippocampus contained extracellular accumulations of Al and amyloid surrounded by nuclei of degenerating cells, which we interpreted as neuritic plaques. The cerebrovasculature was distorted, with a significant thickening of the wall of capillaries, associated with amyloid deposits. These behavioral and neuropathological modifications associated with long-term exposure to Al are reminiscent of those observed in AD.