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.     

Demonstration of T Lymphocytes in Cerebrospinal Fluid

Cerebrospinal fluid (CSF) was allowed to drop straight into Hanks's balanced salt solution. After centrifugation the pellet was resuspended and mixed with sheep erythrocytes. The mixture was further handled as in the E-rosette test with peripheral blood lymphocytes. CSF from 20 individuals were investigated, and rosette-forming cells (RFC) were found in all. Six patients with normal fluid had between 46% and 83% RFC. Four patients with multiple sclerosis had increased numbers of RFC (94%-96%). Low numbers of RFC were found in one patient with cerebellar ataxia and in one of two patients with acute viral meningitis. With this technique RFC can be counted even in normal CSF with a 3-ml sample.     

Genetic evidence on the origins of Indian caste populations

The origins and affinities of the approximately 1 billion people living on the subcontinent of India have long been contested. This is owing, in part, to the many different waves of immigrants that have influenced the genetic structure of India. In the most recent of these waves, Indo-European-speaking people from West Eurasia entered India from the Northwest and diffused throughout the subcontinent. They purportedly admixed with or displaced indigenous Dravidic-speaking populations. Subsequently they may have established the Hindu caste system and placed themselves primarily in castes of higher rank. To explore the impact of West Eurasians on contemporary Indian caste populations, we compared mtDNA (400 bp of hypervariable region 1 and 14 restriction site polymorphisms) and Y-chromosome (20 biallelic polymorphisms and 5 short tandem repeats) variation in approximately 265 males from eight castes of different rank to approximately 750 Africans, Asians, Europeans, and other Indians. For maternally inherited mtDNA, each caste is most similar to Asians. However, 20%-30% of Indian mtDNA haplotypes belong to West Eurasian haplogroups, and the frequency of these haplotypes is proportional to caste rank, the highest frequency of West Eurasian haplotypes being found in the upper castes. In contrast, for paternally inherited Y-chromosome variation each caste is more similar to Europeans than to Asians. Moreover, the affinity to Europeans is proportionate to caste rank, the upper castes being most similar to Europeans, particularly East Europeans. These findings are consistent with greater West Eurasian male admixture with castes of higher rank. Nevertheless, the mitochondrial genome and the Y chromosome each represents only a single haploid locus and is more susceptible to large stochastic variation, bottlenecks, and selective sweeps. Thus, to increase the power of our analysis, we assayed 40 independent, biparentally inherited autosomal loci (1 LINE-1 and 39 Alu elements) in all of the caste and continental populations (approximately 600 individuals). Analysis of these data demonstrated that the upper castes have a higher affinity to Europeans than to Asians, and the upper castes are significantly more similar to Europeans than are the lower castes. Collectively, all five datasets show a trend toward upper castes being more similar to Europeans, whereas lower castes are more similar to Asians. We conclude that Indian castes are most likely to be of proto-Asian origin with West Eurasian admixture resulting in rank-related and sex-specific differences in the genetic affinities of castes to Asians and Europeans.     

Serogenetic investigations of Tibetans and Himachalis from Himachal Pradesh,India: Genetic relationship between Tibetans and certain selected mongoloid populations

Twenty two serogenetic systems were investigated in 115 Tibetans and 128 Himachalis from the state of Himachal Pradesh, north-west India. For eight of the loci (ABO, Rh, MNSs, P, Fy, 6PGD, EsD, and AK) the two populations showed conclusive heterogeneity and their frequency distribution showed that the serogenetic differences between two populations are due to their different racial affliations. The Tibetans were also analysed for their genetic relationship with certain selected populations from the Cis-Himalayan, far east and south Asian regions. The calculations of the Harpending's kinship matrix R and the genetic distances showed that the Tibetans are closer to the mongoloid populations of the Cis-Himalayan region and the differences in the present day population structure of the mongoloid groups of this region are more likely to be due to differential migration, admixture and racial affliation although there is a slight possibility of disruptive selection for certain loci such as 6PGD and AK which showed an exceptionally high value of Canning (6PGD ^*C) andAK ^*1 genes.