Persistent hypokalaemia and abnormal chest radiography.

A case report of an interesting paraneoplastic syndrome http://ow.ly/YGAR3.

Case report: Sudden cardiac death in a young man.

A 35-year-old man presented to the accident and emergency department with history of productive cough, breathlessness and some weight loss over several weeks. He had a past medical history of asthma and eczema. He mentioned that, at times, he had been expectorating sputum with some haemoptysis over the past few months. He was of Bangladeshi origin, but had been resident in the UK since 1986 and last visited Bangladesh a year ago. He was a smoker of 10-15 cigarettes per day. He also admitted to smoking heroin. In addition to his respiratory symptoms he also complained of vomiting, which was precipitated by eating. He denied bowel or urinary symptoms.

Radioprotective effect of Haberlea rhodopensis (Friv.) leaf extract on gamma-radiation-induced DNA damage, lipid peroxidation and antioxidant levels in rabbit blood.

Different concentrations of H. rhodopensis total extract (HRE; 0.03, 0.06 and 0.12 g/kg body weight) were injected im, into rabbits 2 h before collecting the blood samples. The whole blood samples were exposed in vitro to 2.0 Gy 60Co gamma-radiation. The radiation-induced changes were estimated by using the chromosome aberration test (CA) and cytokinesis blocked micronucleus assay (CBMN) in peripheral lymphocytes, and by determining the malondialdehyde levels (MDA) in blood plasma and the superoxide dismutase (SOD) and catalase (CAT) activity in erythrocytes. Radiation significantly increased the chromosome aberration and micronuclei frequencies as well as MDA levels and decreased the antioxidant enzyme activity. On the other hand, the HRE pretreatment significantly decreased the CA, MN frequencies and MDA levels and increased the SOD and CAT activity in a concentration dependent manner. The most effective was the highest concentration of HRE (0.12 g/kg body weight). The results suggest that HRE as a natural product with a nantioxidant capacity could play a modulatory role against the cellular damage induced by gamma-irradiation. The possible mechanism involved in the radioprotective potential of HRE is discussed.

The processing of three-dimensional shape from disparity in the human brain.

Three-dimensional (3D) shape is important for the visual control of grasping and manipulation and for object recognition. Although there has been some progress in our understanding of how 3D shape is extracted from motion and other monocular cues, little is known of how the human brain extracts 3D shape from disparity, commonly regarded as the strongest depth cue. Previous fMRI studies in the awake monkey have established that the interaction between stereo (present or absent) and the order of disparity (zero or second order) constitutes the MR signature of regions housing second-order disparity-selective neurons (Janssen et al., 2000; Srivastava et al., 2006; Durand et al., 2007; Joly et al., 2007). Testing the interaction between stereo and order of disparity in a large cohort of human subjects, revealed the involvement of five IPS regions (VIPS/V7*, POIPS, DIPSM, DIPSA, and phAIP), as well as V3 and the V3A complex in occipital cortex, the posterior inferior temporal gyrus (ITG), and ventral premotor cortex (vPrCS) in the extraction and processing of 3D shape from stereo. Control experiments ruled out attention and convergence eye movements as confounding factors. Many of these regions, DIPSM, DIPSA, phAIP, and probably posterior ITG and ventral premotor cortex, correspond to monkey regions with similar functionality, whereas the evolutionarily new or modified regions are located in occipital (the V3A complex) and occipitoparietal cortex (VIPS/V7* and POIPS). Interestingly, activity in these occipital regions correlates with the depth amplitude perceived by the subjects in the 3D surfaces used as stimuli in these fMRI experiments.

The extraction of 3D shape from texture and shading in the human brain.

We used functional magnetic resonance imaging to investigate the human cortical areas involved in processing 3-dimensional (3D) shape from texture (SfT) and shading. The stimuli included monocular images of randomly shaped 3D surfaces and a wide variety of 2-dimensional (2D) controls. The results of both passive and active experiments reveal that the extraction of 3D SfT involves the bilateral caudal inferior temporal gyrus (caudal ITG), lateral occipital sulcus (LOS) and several bilateral sites along the intraparietal sulcus. These areas are largely consistent with those involved in the processing of 3D shape from motion and stereo. The experiments also demonstrate, however, that the analysis of 3D shape from shading is primarily restricted to the caudal ITG areas. Additional results from psychophysical experiments reveal that this difference in neuronal substrate cannot be explained by a difference in strength between the 2 cues. These results underscore the importance of the posterior part of the lateral occipital complex for the extraction of visual 3D shape information from all depth cues, and they suggest strongly that the importance of shading is diminished relative to other cues for the analysis of 3D shape in parietal regions.

Using functional magnetic resonance imaging to assess adaptation and size invariance of shape processing by humans and monkeys.

Functional magnetic resonance imaging in awake monkeys and humans was used to compare object adaptation in shape-sensitive regions of these two species under identical and different size conditions. Object adaptation was similar in humans and monkeys under both conditions. Neither species showed complete size invariance, in agreement with single-cell studies. Both the macaque inferotemporal (IT) complex and human lateral occipital complex (LOC) displayed an anteroposterior gradient in object adaptation and size invariance, with the more anterior regions being more adaptable and size invariant. The results provide additional evidence for the homology between the macaque IT cortex and human LOC but also add to the growing list of differences between human and monkey intraparietal sulcus regions.

Visual activation in prefrontal cortex is stronger in monkeys than in humans.

The prefrontal cortex supports many cognitive abilities, which humans share to some degree with monkeys. The specialized functions of the prefrontal cortex depend both on the nature of its inputs from other brain regions and on distinctive aspects of local processing. We used functional MRI to compare prefrontal activity between monkey and human subjects when they viewed identical images of objects, either intact or scrambled. Visual object-related activation of the lateral prefrontal cortex was observed in both species, but was stronger in monkeys than in humans, both in magnitude (factors 2-3) and in spatial extent (fivefold or more as a percentage of prefrontal volume). This difference was observed for two different stimulus sets, at two field strengths, and over a range of tasks. These results suggest that there may be more volitional control over visual processing in humans than in monkeys.