Deciphering the Immunological Phenomenon of Adaptive Natural Killer (NK) Cells and Cytomegalovirus (CMV)

Natural killer (NK) cells play a significant and vital role in the first line of defense against infection through their ability to target cells without prior sensitization. They also contribute significantly to the activation and recruitment of both innate and adaptive immune cells through the production of a range of cytokines and chemokines. In the context of cytomegalovirus (CMV) infection, NK cells and CMV have co-evolved side by side to employ several mechanisms to evade one another. However, during this co-evolution the discovery of a subset of long-lived NK cells with enhanced effector potential, increased antibody-dependent responses and the potential to mediate immune memory has revolutionized the field of NK cell biology. The ability of a virus to imprint on the NK cell receptor repertoire resulting in the expansion of diverse, highly functional NK cells to this day remains a significant immunological phenomenon that only occurs in the context of CMV. Here we review our current understanding of the development of these NK cells, commonly referred to as adaptive NK cells and their current role in transplantation, infection, vaccination and cancer immunotherapy to decipher the complex role of CMV in dictating NK cell functional fate.     

An analogue and propositional hybrid model for the perception of computer generated graphical images

This research investigated two alternative models, analogue and propositional, which describe how three-dimensional (3-D) graphical images are represented and stored in human memory. In order to differentiate between the two models, three separate experiments were performed using a variation of the Shepard-Metzler mental rotation paradigm (Shepard and Metzler 1971). For each experiment, the effects of three independent variables on the performance of a 'mental rotation' task were examined: (a) three levels of figure complexity, ( b) three axes of rotation and (c) four angles of rotation. The subjects' task was to compare specific angle, axis or depth versus picture plane rotations for pairs (rotated and non-rotated versions) of 3-D graphic figures displayed on a CRT. The results indicated that response times varied depending on level of figure complexity, axis or angle of rotation. A new hybrid model integrating components of both the analogue and propositional positions is proposed to explain the reaction time data. In this model, analogue processes occur when processing requirements for cognitive tasks are low, whereas propositional processes occur when processing requirements are high. Implications of the results for the internal representation of 3-D images in human memory and for the design of graphic work stations are discussed.     

Binocular distance perception: Egocentric distance tasks.

Tested an extension of the present author's (1978; see also PA, Vol 64:11699) theory of binocular distance perception, which has been shown to give a good account of performance in relative distance tasks. In 2 experiments, 5 18–36 yr olds indicated perceived egocentric distance of targets (perceived distance from him/herself) by means of a verbal report or manual pointing response. In Exp I, the distance to 2 targets was varied while maintaining a constant disparity between them. In Exp II, 1 target was held fixed while the distance to a 2nd target was varied. In each case, Ss indicated the perceived distance of each target. Manual and verbal responses agreed with each other to within a linear transform. Both sets of data are consistent with the theory and indicate that reference parallax is a weighted average of target parallaxes. The systematic inaccuracy of binocular distance perception is attributed to the misperception of egocentric distance to the configuration. (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Back-of-the-envelope miniload throughput bounds and approximations

We derive simple formulas bounding and approximating the throughput of an end-of-aisle miniload system with exponentially distributed pick times and either uniform or turnover-based storage. For typical configurations, the worst-case relative error for the bounds is less than 4%. We use our bounds to show that, for all practical purposes, regardless of the configuration, the picker utilization determines the storage/retrieval machine utilization, and vice versa. Thus, a system designer cannot hope to independently achieve separate goals for the utilization rates.     

Physician-assisted suicide: reflections on Oregon's first case

The authors analyze Oregon's first reported assisted suicide of Mrs. A as a real life application of the Oregon Death with Dignity Act. They critique the effectiveness of the Act's safeguards as illustrated by the case of Mrs. A. They point out that the Act does not require that physicians be adequately trained in palliative care in order to participate in assisted suicide. Most physicians do not have such training. Without it, they are not able to effectively present alternatives to patients requesting assisted suicide. Most physicians also lack the expertise to assess patients' decision-making capacity. Nor does the Act ensure that physicians will be in a position to assess coercion of patients' decisions. The Act requires physicians to report only minimal information about their cases, and there are no enforcement provisions to see that even this is done. Under the Act, a good faith standard rather than the more usual negligence standard immunizes physicians from civil or criminal liability even when they act negligently. The authors demonstrate that the Act protects physicians more than patients, and encourages secrecy. The authors conclude that secrecy will need to be replaced by openness to permit the kind of examination the practice of assisted suicide warrants.     

Diagnostic features of clinical neurologic feline infectious peritonitis

Feline infectious peritonitis (FIP) is a fatal Arthus-type immune response of cats to infection with FIP virus, a mutant of the ubiquitous feline enteric coronavirus (FECV). The disease may occur systemically or in any single organ system, and primary neurologic disease is a common subset of such manifestations. We examined 16 domestic cats with clinical neurologic FIP and 8 control cats with nonneurologic FIP, with the intention of identifying the ante- and postmortem diagnostic tests that most contribute to accurate diagnosis. Of the 16 cats with neurologic FIP, 15 were less than 2 years of age and all 16 originated from large multiple-cat households. The most useful antemortem indicators of disease were positive anti-coronavirus IgG titer in cerebrospinal fluid, high serum total protein concentration, and findings on magnetic resonance imaging suggesting periventricular contrast enhancement, ventricular dilatation, and hydrocephalus. Postmortem diagnosis was facilitated by FIP monoclonal antibody staining of affected tissue and coronavirus-specific polymerase chain reaction. Most cats with neurologic and ocular forms of FIP had patchy, focal lesions, suggesting that recently developed technologies described in this report may be useful for evaluation of cats with suspected FIP.     

Food Cent$--implementing and evaluating a nutrition education project focusing on value for money

The photophysics and polarization of the phosphorescence and delayed fluorescence of erythrosin in conditions compatible with the current biological applications of the dye (aqueous buffers at pH 7.4 at ambient temperatures) and in ethanol have been studied as a function of dye concentration (10(-7)-10(-5) M) and temperature (245-333 K). The emission decay is strictly single exponential and the detailed kinetic analysis of all the rate processes connected with the emitting T1 state showed that (1) the lowering of the emission lifetime at the higher temperatures is due to a very efficient self-quenching process, (2) the back intersystem crossing rate T1-->S1 is temperature dependent (delta ETS approximately 7 kcal mol-1) but the T1-->S0 is not (Ea < 0.1 kcal mol-1) and (3) both intersystem crossing processes are very sensitive to solvent polarity, which accounts for the solvent dependence of the phosphorescence yield and lifetime. The high value of the phosphorescence anisotropy (r0 = 0.25 +/- 0.006) is independent of the excitation and emission wavelengths, and its evolution in time accurately reflects the rotational restrictions in solid solutions. The relevance of these findings to studies with protein-dye conjugates is also outlined to facilitate the design and interpretation of phosphorescence depolarization experiments that probe the microsecond-ms dynamics of biomolecules and supramolecular systems.     

Molecular, clinical, and pathologic comparison of two distinct strains of Haemobartonella felis in domestic cats

PURPOSE: To evaluate the long-term effect of photoastigmatic refractive keratectomy (PARK) on mild keratoconus. SETTING: Laser Unit, Ein Tal Eye Center, Tel Aviv, Israel. METHODS: Eight eyes of 6 patients with stable compound myopic astigmatism and topography features of keratoconus were treated with a VISX Twenty-Twenty excimer laser. The laser beam slit width ranged between 4.8 and 5.0 mm according to the degree of cylinder. Preoperative slitlamp examination did not reveal significant thinning, ectasia, or scarring. Astigmatism ranged between -2.00 and -7.50 diopters and follow-up, between 36 and 48 months. RESULTS: In 7 of 8 eyes, uncorrected visual acuity (UCVA) before PARK ranged between 6/30 and finger counting. After PARK, it ranged between 6/9(-) and 6/15, and patients could manage in most of their daily activities without using spectacles. In 2 eyes, the final UCVA was 6/15(-) and 6/15. In 1 eye, treatment failed to improve UCVA and corneal topography revealed progression of the keratoconus. CONCLUSIONS: Photoastigmatic keratectomy was partially effective in eyes with mild stable keratoconus. However, the long-term results may be altered by progression of corneal thinning and ecstatic disease. In addition to the mild nature of the keratoconus, this is a small series and further studies are needed to confirm these results.     

Mental mapping of a megastructure.

Studied the acquisition of spatial information about a large multifunctional complex building by obtaining distance estimations, confidence judgments, and imagery reports. Ss were undergraduates and prospective undergraduates of a university who varied in their experience with the campus. Fourth-year Ss, who had made intensive use of the campus for at least 28 mo, were the most experienced. First-year Ss, who had used the campus for 3–6 mo, had less experience. Other Ss were visiting the campus for the 1st time. At each level of experience, 6 males and 6 females were tested. Magnitude estimation functions for particular sets of distances were computed for each S using iteratively weighted least squares, yielding an exponent and weights for each distance. Improvement in performance on different measures with increasing experience was not uniform: Certain distances were increasingly in error. Data suggest that abstract schemata operate at all levels of exposure but that structural consistency increases. Directional asymmetries in distance judgments that accompanied shifts in imagery are evidence for qualitatively different encodings of the environment: abstract vs scenographic. It is argued that superior performance on the distance estimation task depends on the construction of a dynamic abstract representation or "working map." (French abstract) (44 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Unilateral asymptomatic carotid disease does not require surgery

If a stimulus (e.g. tone or light) is repeatedly pre-exposed without consequences, it subsequently shows retarded conditioning when paired with a reinforcer (e.g. footshock) compared with a non-pre-exposed stimulus. This is latent inhibition (LI). Haloperidol-treated animals show potentiated LI, and it has been suggested that this is due to retarded switching to respond according to the stimulus-reinforcer contingency. Recently, it has been argued that the slowed control of behaviour by the stimulus-reinforcement contingency is due to a haloperidol-induced decrease in the impact, or salience, of the reinforcer, and thus should be antagonized by increasing the impact of reinforcement. Two experiments tested this prediction. In both, LI was assessed using an off-baseline conditioned emotional response procedure in rats licking for water. In Experiment 1, rats were given 10 light pre-exposures and conditioned with two footshocks of either a low (0.5 mA) or a high (1 mA) intensity. In Experiment 2, rats were given 30 pre-exposures and conditioned with either two or five footshocks of 1 mA. In Experiment 1, no-drug controls did not show LI at both shock intensities. Haloperidol (0.1 mg/kg) was ineffective in potentiating LI at low-intensity shock, but produced LI when shock level was increased. In Experiment 2, no-drug controls showed LI with two but not five conditioning trials. Haloperidol was ineffective in potentiating LI with two conditioning trials, but produced LI with five conditioning trials. Although the effect of haloperidol on LI could thus be modified by manipulating shock intensity or the number of conditioning trials, the direction of such modification indicates that the potentiating effect of haloperidol on LI is not in general antagonized by increasing the impact of reinforcement.