Real and illusory contour processing in area V1 of the primate: a cortical balancing act.

It is known that neurons in area V2 (the second visual area) can signal the orientation of illusory contours in the primate. Whether area V1 (primary visual cortex) can signal illusory contour orientation is more controversial. While some electrophysiology studies have ruled out illusory signaling in V1, other reports suggest that V1 shows some illusory-specific response. Here, using optical imaging and single unit electrophysiology, we report that primate V1 does show an orientation-specific response to the 'abutting line grating' illusory contour. However, this response does not signal an illusory contour in the conventional sense. Rather, we find that illusory contour stimulation leads to an activation map that, after appropriate subtraction of real line signal, is inversely related to the real orientation map. The illusory contour orientation is thus negatively signaled or de-emphasized in V1. This 'activation reversal' is robust, is not due merely to presence of line ends, is not dependent on inducer orientation, and is not due to precise position of line end stimulation of V1 cells. These data suggest a resolution for previous apparently contradictory experimental findings. We propose that the de-emphasis of illusory contour orientation in V1 may be an important signal of contour identity and may, together with illusory signal from V2, provide a unique signature for illusory contour representation.     

Review of Immune Function,Healing of Pressure Ulcers,and Nutritional Status in Patients with Spinal Cord Injury

Abstract

The immune, neural, and endocrine systems do not act autonomously; rather, multiple communicative pathways exist among the nervous, endocrine, and immune systems that facilitate physiological immunoregulation. Patients with spinal cord injury (SCI) have decreased natural and adaptive immune responses by 2 weeks after injury. In patients with SCI, adrenocorticotropic hormone (ACTH) and urine-free cortisol levels were increased while zinc and albumin levels were decreased, respectively. In addition, the surface markers α2, α3, α4, CD11 a, CD11 b, CD1S, CD 54, and CDS found on lymphocytes and α3, α4, CD11a, CD1S, and CDS surface markers found on granulocytes were also decreased in the patient population. Finally, the adhesion molecules binding ability in the SCI group was also decreased when compared with a control group. Overall, the investigation showed that patients with SCI have a decreased immune function, especially succeeding the SCI injury, an impaired nutrition status, and a decreased number of adhesion molecules, all of which contribute to delayed wound healing.     

Carotenoid and retinol composition of South Asian foods commonly consumed in the UK

The main aim of this study was to provide new and reliable food composition data on carotenoids and retinol in South Asian Foods for the United Kingdom's national database. A total of 38 commonly consumed foods were analysed using HPLC and accredited methods of analyses. Palak paneer (spinach and soft Indian cheese) contained the highest levels of β-carotene (4066 μg/100 g) followed by gajjeralla (carrot based sweet, 2324 μg/100 g) and saag (mixed green leafy vegetables), which contained 1514 μg/100 g, whilst retinol was present in only a few foods, with ghee being the major source (968 μg/100 g). Meat dishes contained higher amounts of lycopene (up to 1140 μg/100 g in chicken balti) than vegetable or dhal dishes (highest in palak paneer 317 μg/100 g), because of larger quantities of tomatoes used in meat curries. A variety of ethnic vegetables (green leafy vegetables and other coloured vegetables), namely legumes/dhal, tomatoes and coriander, were identified to be the major ingredients containing carotenoids. These new data can be used in future diet and nutrition surveys, as well as to identify carotenoid-rich foods for dietary programs.