Interleukin 2 and mitogen driven proliferation in human peripheral mononuclear cells: a kinetic analysis

The role of the T lymphocyte growth factor, interleukin 2 (IL2), on human lymphocyte proliferation was investigated. The results define the extent and the chronological sequence of IL2 effects on unstimulated mononuclear cells and on an activated population enriched in IL2 receptor positive cells. Important differences were observed in the proliferative response to the mitogen PHA when the IL2 concentration in the culture medium was varied. The data suggest that IL2 concentration is critical in the responsiveness to a mitogenic stimulus.     

Neuroimmune mechanisms in health and disease: 2. Disease.

In the second part of their article on the emerging field of neuroimmunology, the authors present an overview of the role of neuroimmune mechanisms in defence against infectious diseases and in immune disorders. During acute febrile illness, immune-derived cytokines initiate an acute phase response, which is characterized by fever, inactivity, fatigue, anorexia and catabolism. Profound neuroendocrine and metabolic changes take place: acute phase proteins are produced in the liver, bone marrow function and the metabolic activity of leukocytes are greatly increased, and specific immune reactivity is suppressed. Defects in regulatory processes, which are fundamental to immune disorders and inflammatory diseases, may lie in the immune system, the neuro endocrine system or both. Defects in the hypothalamus-pituitary-adrenal axis have been observed in autoimmune and rheumatic diseases, chronic inflammatory disease, chronic fatigue syndrome and fibromyalgia. Prolactin levels are often elevated in patients with systemic lupus erythematosus and other autoimmune diseases, whereas the bioactivity of prolactin is decreased in patients with rheumatoid arthritis. Levels of sex hormones and thyroid hormone are decreased during severe inflammatory disease. Defective neural regulation of inflammation likely plays a pathogenic role in allergy and asthma, in the symmetrical form of rheumatoid arthritis and in gastrointestinal inflammatory disease. A better understanding of neuroimmunoregulation holds the promise of new approaches to the treatment of immune and inflammatory diseases with the use of hormones, neurotransmitters, neuropeptides and drugs that modulate these newly recognized immune regulators.     

Amebic liver abscess: diagnosis and treatment evaluation with MR imaging

Magnetic resonance images were obtained before and after treatment in 17 patients with 29 amebic liver abscesses. Pretreatment T1-weighted images showed a sharply circumscribed, heterogeneous, low-signal-intensity mass, devoid of normal hepatic tissue and corresponding to the abscess cavity as measured sonographically. T2-weighted images showed the abscess cavity as a hyperintense region and also showed a larger region of hyperintensity extending from the cavity margins to the liver surface, corresponding to edematous but morphologically normal liver tissue. After treatment, the abscess cavity became homogeneously hypointense on T1-weighted images, corresponding to liquefaction of the abscess center. With successful treatment, concentric rings corresponding to (a) an inner margin of inflamed granulation tissue, (b) bands of type I collagen, and (c) the outer margin of atrophic and/or mildly inflamed liver tissue became prominent on T1- and T2-weighted images. T2-weighted images showed rapid resolution of the perifocal hepatic edema.     

MRI of female genital and pelvic organs during sexual arousal

We utilized contrast enhanced magnetic resonance imaging (MRI) to delineate the anatomy of the female genital and pelvic organs during sexual arousal. Eleven healthy pre-menopausal women and eight healthy post-menopausal women underwent MRI of the pelvis while watching an erotic video. A 1.5 Tesla MR system was used to produce T1-weighted images following administration of MS-325, a gadolinium-based blood pool contrast agent. Selected structural dimensions and enhancement were measured prior to and during sexual arousal. In both pre- and post-menopausal subjects, vestibular bulb and labia minora width increased with arousal. Enhancement measurements increased in the bulb, labia minora and clitoris in both pre- and post-menopausal subjects, and in the vagina in pre-menopausal subjects. There were no marked changes in size or enhancement of the labia majora, urethra, cervix, or rectum during sexual arousal in pre- or post-menopausal subjects. Using MRI, we observed specific changes in the female genitalia and pelvic organs with sexual arousal, in both pre- and post-menopausal women. MRI can potentially provide detailed anatomical information in the assessment of female sexual function, particularly with regard to changes in blood flow.     

Involvement of ryanodine receptors in sphingosylphosphorylcholine-induced calcium release from brain microsomes

Sphingosylphosphorylcholine (SPC) releases Ca²⁺ from brain microsomes. SPC-induced Ca²⁺ release differs from IP₃-induced Ca²⁺ release in that it is more extensive in the cerebrum than in the cerebellum. SPC has little effect on [³H] IP₃ binding but enhances [³H] ryanodine binding, as expected for an activator or ryanodine receptors. SPC-induced Ca²⁺ release is inhibited by ryanodine receptor blockers but not by selective blockers of IP₃ receptors. We conclude that SPC releases Ca²⁺ from brain microsomes by activating ryanodine receptors rather than IP₃ receptors. Activation of an additional SPC-sensitive pathway for releasing Ca²⁺ is not precluded.     

Drawing abilities in Williams syndrome: a case study

Children with Williams syndrome (WS) have been reported to exhibit an unusual cognitive profile characterized by marked preservation of linguistic abilities and poor visuospatial abilities against a backdrop of generalized mental retardation. Much of the data documenting this profile come from studies of older children and adults with WS. Very few studies have reported findings from the preschool and early school-age period. As a result, little is known about the early development of cognitive processes in children with WS. Capirci, Sabbadini, and Volterra (1996) reported data from a longitudinal case study of early language development in a young child with WS. This article presents the longitudinal profile of visuospatial abilities in this same child. Data on copying and free drawing collected over a period extending from late preschool to early school age are reported. It is clear from these data that this child does indeed exhibit deficits in visuospatial abilities. Her performance clearly improved with age, but deficits persist.