Treatment of Acquired Bilateral Nevus of Ota-Like Macules (Hori''s Nevus) with a Combination of the 532 nm Q-Switched Nd:YAG Laser Followed by the 1,064 nm Q-Switched Nd:YAG Is More Effective: Prospective Study

BACKGROUND: Acquired bilateral nevus of Ota-like macules (Hori's nevus) is a common dyschromatosis among Asian women. Q-switched lasers have been used successfully as a treatment modality. OBJECTIVE: The purpose of this study was to compare the efficacy of using the Q-switched 532 nm neodymium:yttrium-aluminum-garnet (Nd:YAG) laser followed by the 1,064 nm laser versus the Q-switched 1,064 nm Nd:YAG laser alone in the treatment of Hori's nevus. METHODS: This is a prospective left-right comparative study. Ten women with bilateral Hori's nevus were recruited and treated with a combination of the Q-switched 532 and 1,064 nm Nd:YAG lasers on the right cheek and the Q-switched 1,064 nm Nd:YAG laser alone on the left cheek. Only one laser treatment session was performed. The degree of pigmentation was objectively recorded with a mexameter. Subjective assessment was made by both patients and two blinded, nontreating dermatologists. RESULTS: At 6 months, there was a statistically significant difference (p = .009) of 35.10 points using objective mexameter measurements between the two sides, favoring the side treated with a combination of 532 and 1,064 nm laser treatment. Subjective grading by the patients and blinded dermatologists also confirmed that combination therapy was more successful after one treatment. Although combination treatment had a higher incidence of mild postinflammatory changes, this disappeared within 2 months. CONCLUSIONS: Concurrent use of the Q-switched 532 nm Nd:YAG laser in combination with the 1,064 nm laser is more effective in pigment clearance than the Q-switched 1,064 nm Nd:YAG laser alone for Hori's nevi.     

Cyclosporin-A nephrotoxicity and acute cellular rejection in renal transplant recipients: correlation between radionuclide and histologic findings

Serial radionuclide studies using both Tc-99m DTPA (perfusion) and I-131 hippuran (tubular function) were correlated with histologic findings in 25 patients with renal transplants. These cases included 15 cases of cyclosporin-A nephrotoxicity (CsA-NT) and ten cases of acute cellular rejection that were retrospectively selected on the basis of biopsy findings and favorable clinical response to therapy specific for each of these conditions. The serial radionuclide studies enabled the correct diagnosis in 12 of 15 cases of CsA-NT and eight of ten cases of acute rejection. Posttherapy radionuclide studies, furthermore, demonstrated improvement consistent with clinical response. In all cases, the radionuclide results were available at least 24 hours before biopsy findings. These results indicate that serial radionuclide studies evaluating interval changes in both perfusion and tubular function are of significant value in the diagnosis and follow-up of CsA-NT and acute cellular rejection in transplant recipients. This initial experience suggests a sensitivity of 80%.     

Influence of thyroid hormones on rat cerebellar cell aggregation and survival in culture

In order to study the effect of thyroid hormones on rat cerebellar granule cells, cerebellar perikarya isolated from 5-7-day-old rats were cultured in the presence of normal fetal calf serum, fetal calf serum treated with Dowex-2 ion exchange resin to remove thyroid hormones, or ion exchange-treated serum resupplemented with physiological concentrations of T4 and T3. Granule cells grown under hypothyroid conditions showed abnormal cellular aggregation, neurite fasciculation and cell survival. Cell aggregation, which may be an in vitro correlate of cerebellar granule cell migration to the internal granule layer, was reduced by over 50% under hypothyroid conditions. The rate of protein synthesis in hypothyroid cultures was stimulated by as much as 3-fold compared to thyroid hormone-containing cultures consistent with a proposal that the normal developmental pattern of diminishing protein synthesis specific activity is delayed or prevented under hypothyroid conditions. In addition ultrastructural studies revealed abnormalities in the density of cold-stable microtubules in thyroid hormone-deficient cultures. These results demonstrate that thyroid hormones can influence granule neuron behavior in the absence of Purkinje cells. Furthermore, the observed defects bear numerous similarities to documented abnormalities within the hypothyroid cerebellum, suggesting that this in vitro culture system may serve as a useful model for studying the mechanism of action of thyroid hormones on the cells of the cerebellum.     

Intercellular adhesion molecule‐1 gene polymorphisms in Behçet’s disease

Intercellular adhesion molecule‐1 (ICAM‐1) gene polymorphisms have been implicated in the susceptibility to inflammatory diseases, including multiple sclerosis and inflammatory bowel disease. The expression of both soluble and tissue ICAM‐1 is increased in Behçet’s disease (BD) but the contribution of ICAM‐1 gene polymorphisms to this disease remains unknown. Associations with BD have been reported for genes within the MHC, including HLA‐B51, TNF and MICA, but the role of non‐MHC genes in BD remains largely unexplored. We have investigated the frequency of the R/G 241 and K/E 469 ICAM‐1 gene polymorphisms in 83 patients with BD disease and 103 healthy controls, all of Palestinian and Jordanian descent, and demonstrated an association between BD and the ICAM‐1 E469 allele (P_c = 0.046, OR = 2.1). Among patients, no association was found between the presence of ocular disease and ICAM‐1 polymorphisms. While the functional correlate of this polymorphism remains unclear, this finding indicates that a genetic polymorphism in the ICAM‐1 gene domain, which is independent of the MHC, may contribute to disease.     

Polymyositis-dermatomyositis: diagnostic and prognostic significance of muscle alkaline phosphatase.

The distribution and intensity of alkaline phosphatase deposition in 54 patients with dermatomyositis-polymyositis (PM-DM) was analyzed by the enzyme histochemical method. Increased enzyme reactivity of endomysial capillaries was found in 28% of patients, equally distributed between adult onset PM (Group I) and PM-DM with overlap in other connective tissue diseases (Group V). Patients with high endomysial capillary reactivity (R1 larger than or equal to 60) responded poorly to steroids, had an increased incidence of rheumatoid factor, and had less fiber degeneration/necrosis in their biopsies. Twenty-two percent of patients demonstrated prominent perimysial phosphatase reactivity localized in newly formed collagen and fibroblasts. Thirty patients (55%) demonstrated significant numbers of alkaline-phosphatase-positive fibers positively correlated with increased fiber degeneration/necrosis, endomysial fibrosis, increased numbers of triglyceride-containing muscle fibers, and NADH tetrazolium reductase hyperreactivity. Minimal overlap between the three enzyme distribution patterns was found. Endomysial capillary activity probably represents endothelial alkaline phosphatase induction analogous to the pattern seen normally in lower mammals (rat, rabbit, guinea pig). Alkaline phosphatase fiber reactivity probably represents a particular phase in fiber regeneration/maturation especially after denervation and is positively correlated with an increased incidence of spontaneous fibrillation potentials in PM-DM.     

Natural killer cell immunoglobulin-like receptor (KIR) locus profiles in African and South Asian populations

Natural killer (NK) and some T cells express killer cell immunoglobulin-like receptors (KIRs), which interact with HLA class I expressed by target cells and consequently regulate cytolytic activity. The number of KIR loci can vary and so a range of genetic profiles is observed. We have determined the KIR genetic profiles from one African (n = 62) and two South Asian (n = 108, n = 78) populations. Several of the KIRs are present at significantly different frequencies between the two major ethnic groups (eg KIR2DS4 gene frequency 0.82 African, 0.47 S Asian. Pc < 1 x 10(-6)) and this is due to uneven distribution of two KIR haplotype families 'A' and 'B'. All three populations described here displayed a greater degree of diversity of KIR genetic profiles than other populations investigated, which indicates further complexity of underlying haplotypes; in this respect we describe two individuals who appear homozygous for a large deletion including the previously ubiquitous 2DL4. We have also reanalysed three populations that we studied previously, for the presence of a KIR which is now known to be an indicator of the 'B' haplotype. South Asians had the highest overall frequencies of all KIR loci characteristic of 'B' haplotypes (Pc < 0.0001 to < 0.004). Furthermore, gene frequency independent deviances in the linkage disequilibrium were apparent between populations.     

Interchromosomal duplications of the adrenoleukodystrophy locus: a phenomenon of pericentromeric plasticity

A 9.7 kb segment encompassing exons 7-10 of the adrenoleukodystrophy (ALD) locus of the X chromosome has duplicated to specific locations near the pericentromeric regions of human chromosomes 2p11,10p11, 16p11 and 22q11. Comparative sequence analysis reveals 92-96% nucleotide identity, indicating that the autosomal ALD paralogs arose relatively recently during the course of higher primate evolution (5-10 million years ago). Analysis of sequences flanking the duplication region identifies the presence of an unusual GCTTTTTGC repeat which may be a sequence-specific integration site for the process of pericentromeric- directed transposition. The breakpoint sequence and phylogenetic analysis predict a two-step transposition model, in which a duplication from Xq28 to pericentromeric 2p11 occurred once, followed by a rapid distribution of a larger duplicon cassette among the pericentromeric regions. In addition to facilitating more effective mutation detection among ALD patients, these findings provide further insight into the molecular basis underlying a pericentromeric-directed mechanism for non- homologous interchromosomal exchange.