Efferent connections of the basal forebrain in the cat: the substantia innominata

The efferent connections of the substantia innominata in the cat were studied with radioautographic methods. Injections of [³H]leucine were placed throughout the substantia innominata in 20 cats. The results indicate a complex organization to the efferent distribution of fibers from this region. The projections associated with more caudomedial regions of the substantia innominata resemble those of the adjacent preoptic-hypothalamic area and innervate the septal area, lateral habenular nucleus, and ventral tegmental area. Fibers arising from more caudolateral parts of the substantia innominata (ventral pallidum) appear to project in a crude topographic manner to the amygdala via two routes—the stria terminalis and a second group of caudolaterally directed axons. The fiber distribution from the region of the nucleus basalis is widespread to a variety of cortical sites, such as the olfactory bulb, prefrontal cortex, anterior cingulate gyrus, pyriform, and posterior sylvian cortices. Fibers arising from the rostral aspect of the substantia innominata adjacent to the nucleus accumbens are distributed exclusively to the ventral tegmental area and adjoining substantia nigra. All parts of the substantia innominata supply the ventral tegmental area.     

Serum soluble interleukin-2 receptor levels in chronic progressive, stable and steroid-treated multiple sclerosis

Serum levels of the soluble interleukin-2 receptor (sIL-2R), an indicator of T cell activation, were significantly elevated in chronic progressive MS (CPMS) patients, clinically stable MS patients and in patients with other neurological diseases (OND) as compared to healthy controls. Levels of sIL-2R in steroid treated CPMS patients were markedly lower than in untreated CPMS patients and were comparable to healthy controls. Thus, systemic T cell activation occurs in MS during clinically stable and progressive disease stages and in other neurological disorders. The ability of oral corticosteroids to depress serum sIL-2R levels in vivo may be one mechanism by which they exert their therapeutic effect.     

Increased free light chains in the urine from patients with multiple sclerosis

We quantitated free kappa (kappa) and lambda light (L) chains in coded urine specimens from subjects with clinically definite multiple sclerosis (MS) (N = 56), other neurologic diseases (OND) (N = 30), and age-matched normal controls (N = 28). Urine from MS patients showed statistically significant increases in free L chains compared with the other groups, although there was overlap between MS patients and OND patients. The ratio of kappa/creatinine was significantly greater in the relapsing-remitting MS group than in patients with clinically stable MS, OND, and normal controls. Elevated free L chains were usually independent of urinary albumin and beta 2-microglobulin levels. Serial studies showed that urinary free kappa/creatinine ratios were elevated during periods of clinical worsening in seven of eight MS patients and subsequently decreased during clinical recovery. The measurement of free L chains in urine obtained at intervals from MS patients may be useful as a marker to monitor disease activity.     

The superior laryngeal nerve: an anatomical structure at risk during thyroid surgery

The effects of injury to the external branch of the superior laryngeal nerve (ESLN) during thyroid surgery are well known, while the frequency and consequences of ESLN lesions aren't today well known. The Authors report their own experience of the incidence of ESLN injuries in thyroid surgery.     

Combination total lymphoid irradiation and low-dose corticosteroid therapy for progressive multiple sclerosis

Total lymphoid irradiation (TLI) has been reported to delay deterioration in patients with progressive multiple sclerosis and other autoimmune disorders. Methods — In an open trial, the effect of TLI combined with a one year course of low dose prednisone was compared to the effect of sham TLI and TLI only in a prior double-blind study of patients with progressive multiple sclerosis. Results — Twenty-seven patients receiving TLI combined with corticosteroids had significantly greater lymphocytopenia in the year post-therapy than those receiving TLI only or sham TLI and Kaplan Meier product-limit survival analysis showed significantly less progression in the TLI plus steroid group over 4 years of follow-up. No difference in lymphocytopenia or progression was found with TLI plus corticosteroid therapy when the spleen was removed from the field of irradiation. Conclusion — These results lend further support to the hypothesis that TLI may be effective in progressive MS, and indicates that adding low-dose prednisone may enhance this effect. The study also suggests that TLI may be equally effective whether or not the spleen is irradiated.     

In vitro studies in reproductive immunology. - 2. Demonstration of the inhibitory effect of male genital tract constituents on PHA-stimulated mitogenesis and E-rosette formation of human lymphocytes

The effect of male genital tract components (human spermatozoa, intact and chromatographed seminal plasma fractions) on in vitro cell-mediated immune reactions was examined. Their addition to PHA-containing lymphocyte cultures resulted in a marked degree of inhibition of DNA synthesis, the response varying with the fractions employed. The interference by such components with a terminal cell event during blast transformation was suggested by the failure of stimulated cultures to incorporate thymidine irrespective of the time during the incubation period at which the constituents were added. Seminal plasma and sperm extracts were also shown to inhibit T-cell associated E-rosette formation. The inhibitory properties of genital fractions remained unaltered after repetitive freeze-thaw cycling when tested in the transformation and E-rosette assays. Heating to 100 degrees C modified the response with some of the fractions.     

Osteoclasts Lacking Rac2 Have Defective Chemotaxis and Resorptive Activity

The role of the small Rho GTPase Rac2 in mature osteoclasts has not been extensively studied. Rac2^−/− mice are of normal size and have normal tooth eruption. However, femoral cortical thickness was significantly greater in Rac2^−/− compared to wild-type mice, while percent cortical porosity was lower. As assessed by histomorphometry, trabecular bone mass was significantly higher in male Rac2^−/− than wild-type animals, although trabecular bone mass was similar when data from male and female animals were combined. There were no significant differences in the number of osteoblasts per bone surface; however, the number of osteoclasts per total bone area tended to be higher in Rac2^−/− mice and was significantly higher in male Rac2^−/− mice. In the aggregate, these data suggested a defect in osteoclast function and, consistent with that, rates of bone resorption were significantly reduced in Rac2^−/− osteoclasts. In addition, Rac2^−/− osteoclasts had a significantly delayed spreading response to treatment with CSF1 for 15 min. Phalloidin staining showed areas of abnormal actin accumulation and impaired actin ring formation in Rac2^−/− osteoclasts. Finally, Rac2^−/− osteoclasts showed a marked defect in chemotaxis toward a point source of CSF1, with a dramatic reduction in migratory rate. Together, these findings indicate an important role for Rac2 in mature osteoclasts.