Clinical and histopathological findings of ''psoriatic neurodermatitis'' and of typical lichen simplex chronicus

BACKGROUND: We have seen several patients with itchy lichenified plaques located bilaterally on the elbows and/or knees and have named this condition 'psoriatic neurodermatitis' (PN). OBJECTIVE: The purpose of this study was to compare clinical and histopathological characteristics of these patients to those of patients with typical lichen simplex chronicus (LSC). METHODS: Nineteen patients with PN and 34 patients with typical LSC were included. Besides clinical dermatological evaluation, the prick test was carried out on 49 patients; the Phadiatop test on 40 patients; the patch test with European standard series on 47 patients; histopathological evaluation on 39 patients; and clinical psychiatric examination on 38 patients. RESULTS: Almost exclusively, PN was seen in females and was located on the extremities. It caused more plaques than typical LSC did. In PN, the plaques were smaller, sharper, more keratotic and less excoriated, and had fewer lichenoid papules around them. Itching was usually more severe in the evening, while resting and in a hot environment in typical LSC, but not in PN. In plaques of PN, microabscesses in the horny layer, hypogranulosis, regular acanthosis and thinning of the suprapapillary plates were more frequent, and hyperpigmentation in the basal layer was less. In patients with PN, depressive disorder was found more frequently; and generalized anxiety disorder or psychosomatic characteristics, less. There were no significant differences in the results of prick, Phadiatop and patch tests between patients with PN and those with typical LSC. CONCLUSION: In our opinion, it is most likely that the so-called PN is itchy psoriasis superimposed by LSC.     

Chronic Administration of Glucocorticoids Directly Upregulates Prepro-Neuropeptide Y and Y1-Receptor mRNA Levels in the Arcuate Nucleus of the Rat

The complete sequence of the cDNA encoding the neuropeptide Y (NPY) Y₁-receptor has recently been deduced from a rat brain library, and the presence of messenger ribonucleic acid (mRNA) encoding Y₁-receptor protein has been demonstrated within the brain. Using quantitative in situ hybridization histochemistry, the content and distribution of Y₁receptor and preproNPY mRNAs have been investigated in the hypothalamic arcuate nucleus of adrenalectomized rats receiving glucocorticoid replacement therapy for 12 days by means of either high doses of dexamethasone in their drinking water or by subcutaneous corticosterone pellets. Basal metabolic parameters such as weight gain or loss, blood glucose and plasma insulin were monitored: Dexamethasone treatment induced weight loss and a state of hyperinsulinemia with normoglycemia, while corticosterone treated animals displayed metabolic parameters identical to sham ADX animals. Within the arcuate nucleus of glucocorticoid treated animals, levels of Y₁receptor and preproNPY mRNAs were increased. In contrast, adrenalectomy itself had no effect upon Y₁-receptor mRNA levels or preproNPY mRNA levels in the arcuate nucleus. These studies demonstrate that glucocorticoids exert a stimulatory action on levels of Y₁-receptor mRNA and preproNPY mRNA levels in the hypothalamic arcuate nucleus. This is the first evidence to suggest that the expression of a neuropeptide-receptor gene in the central nervous system may be directly sensitive to peripheral hormonal signals.     

Visualization of efferent retinal projections by immunohistochemical identification of cholera toxin subunit B.

The present study describes the use of cholera toxin subunit B as an anterograde and retrograde neuronal tracer for studying retinal projections of the rat, mouse, gerbil, and hamster. The tracer was pressure injected in the posterior chamber of the eye and the labeled neurons were identified using an avidin-biotin immunoperoxidase technique using diaminobenzidine as chromagen. Doses of 3-8 microliters (30-80 micrograms) cholera toxin subunit B and a survival for 24 h resulted in an optimal transport of the tracer in all rodent species investigated. The cholera toxin subunit B-containing retinal efferents were effectively stained and yielded the presence of axons with delicate boutons on passage and nerve endings. Smooth and thick fibers were also observed, indicating a distinction between passing and terminating axons, respectively. Immunoreactive axons were observed in the hypothalamus, thalamus, ad mesencephalon, and the precise distribution of positive nerves could be identified in counterstained sections, some of them as delicate endings in apposition to neuronal surfaces. Labeled cell bodies were observed in the oculomotor nucleus and the pretectum, indicating that the tracer is transported retrogradely as well. Because the tracer is identified immunohistochemically, the retinofugal and retinopetal pathways can be mapped more precisely, perhaps in combination with immunohistochemical detection of other antigens.     

Nimodipine treatment of subarachnoid hemorrhage

In a pilot study of 6 patients with subarachnoid hemorrhage caused by a ruptured intracranial (grade IV (Hunt and Hess) aneurysm the hemodynamics and plasma-nimodipine concentrations have been observed during a 3-week period of treatment. We found that 3 patients developed reversible hypotension during the nimodipine treatment and that the hypotension tendency could be related to the plasmanimodipine level and not to a more or less severe sensitivity to nimodipine.

Repeated measurements of blood pressure, plasma-nimodipine and regional cerebral blood flow (rCBF) are necessary for the purpose of obtaining the optimum treatment and for evaluating the effect of treatment.     

Spontaneous abortion following mid-trimester amniocentesis. Clinical significance of placental perforation and blood-stained amniotic fluid

The clinical significance of placental perforation and blood-stained amniotic fluid was studied in a group of 7238 Danish women undergoing mid-trimester amniocentesis for prenatal diagnosis under ultrasound guidance. The risk of spontaneous abortion was significantly increased both in pregnancies where the placenta was perforated and in those with blood-stained amniotic fluid. The risk estimate nearly doubled after placental perforation and more than doubled with a bloody tap. It is concluded that for women at relatively low risk of a fetal genetic abnormality, the indication of the amniocentesis should be reconsidered if a placental perforation is unavoidable.     

Demonstration of a neuronal projection from the entopeduncular nucleus to the substantia nigra of the rat.

The two neuronal tracers, Phaseolus vulgaris leucoagglutinin (PHA-L) and Cholera toxin subunit B (CHB) were used in order to study a possible neuronal projection from the entopeduncular nucleus to the ventral mesencephalon in the rat. Both tracers were identified in brain sections by means of immunohistochemistry. After injection of PHA-L in the entopeduncular nucleus PHA-L-positive nerve fibers observed in the mesencephalon were moderate in number and mostly restricted to the mediodorsal part of the substantia nigra, pars reticulata. In addition, a low number of PHA-L-immunoreactive nerve fibers was found in the substantia nigra, pars compacta, the rostral part of the ventral tegmental area, and in the deep mesencephalic nucleus. In agreement with these observations, several labeled neurons were observed in the ipsilateral entopeduncular nucleus after injections of CHB in the substantia nigra. These results indicate the presence of a direct neuronal projection between the two major output channels of the basal ganglia.