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The 230-kDa bullous pemphigoid antigen (BPAG1) is an integral component of hemidesmosomes. We have previously reported that interferon-γ (IFNγ) inhibits the transcription of the BPAG1 gene ( 1 ). Here we investigated the target sequences of IFNγ-signal transduction pathway in the BPAG1 promoter in epidermal keratinocytes. Transient transfections with 5′-deletion constructs of BPAG1 promoter-luciferase reporter gene plasmids in cultured normal human epidermal keratinocytes (NHEK) allowed us to narrow the DNA region containing IFNγ inhibitory element (IGIE) to between −1 and −89, upstream from the transcription initiation site (+1). Homology search in this region identified a chimeric sequence, consisting of IFN-stimulated responsive element (ISRE) with a partial 7-bp sequence of IFNγ activation site (GAS), as identified in the guanylate-binding protein (GBP) gene, inserted at its center. Functional analysis of IGIE, inserted in front of the heterologous thymidine kinase promoter, indicated that IGIE acts as a down-regulatory element of the promoter through IFNγ-dependent signal pathway. Transient transfection studies with BPAG1 promoter-reporter gene constructs containing mutated IGIE (with TT to GG transversions in the region of 5′ISRE, GAS, and 3′ISRE) demonstrated that disruption of the ISRE sequences, but not GAS, markedly suppressed the BPAG1 basal promoter activity and resulted in attenuated IFNγ response in keratinocytes. Our findings provide novel insight into the mechanism of IFNγ regulation in keratinocyte differentiation and proliferation. [ABSTRACT FROM AUTHOR]

Acute renal failure due to leukemic infiltration into the kidney is rare in childhood acute lymphoblastic leukemia (ALL). We report here a five year-old boy with ALL who presented acute renal failure caused by leukemic infiltration at onset. Treatment with predonisolone and hemodialysis was effective. However, he showed persistent or repeated relapses at extramedullary sites, such as central nervous system, testis, and pancreas, suggesting that leukemic cells of this patient may have had a high affinity to extramedullary organs. On the basis of previous reports and the experience of this patient, intensive treatment may be needed in ALL children with renal involvement. [ABSTRACT FROM AUTHOR]

Summary. The retinoblastoma protein-interacting zinc finger gene (RIZ), a member of the nuclear protein methyltransferase superfamily, is characterized by the presence of the N-terminal PR domain. The RIZ gene encodes for two proteins, RIZ1 and RIZ2. While RIZ1 contains the PR (PRDI-BF1 and RIZ homologous) domain, RIZ2 lacks it. RIZ gene expression is altered in a variety of human cancers and RIZ1 is now considered to be a candidate tumour suppressor. To investigate the role of RIZ in leukaemogenesis, we analysed the differential expression of RIZ1 and RIZ2 by quantitative real-time reverse-transcription polymerase chain reaction assay. Our results showed that the expression of RIZ1 was significantly decreased in leukaemia cell lines (14 out of 17, 82%) and in patients with acute myeloblastic leukaemia (eight out of 14, 57%). In contrast, RIZ2 expression was increased in patients with acute lymphoblastic leukaemia (eight out of 11, 73%), compared with normal bone marrow cells. These findings indicate that suppression of RIZ1 expression or enhancement of RIZ2 expression may have an important role in leukaemogenesis. [ABSTRACT FROM AUTHOR]

An enzymatic study of cultured skin fibroblasts was made in 28 patients with lactic acidosis. In three of these patients a diagnosis of Leigh's encephalomyelopathy was established from autopsy findings. Pyruvate decarboxylase (PDC) deficiency was found in four patients. In two of them, in whom Leigh's encephalomyelopathy was proved by autopsy, PDC activity was lower than 10% of the normal. The other two living patients, who showed 22%-25% of the normal activity, had clinical symptoms and courses different from Leigh's disease. These findings suggest that the patients with severe PDC deficiency develop Leigh's disease but those with mild deficiency may not. A deficiency of cytochrome c oxidase was found in two siblings. One of them, who was diagnosed as having Leigh's encephalomyelopathy by postmortem examination, showed a reduction of cytochrome c oxidase in the liver and brain. In the other sibling, who is living, the reduction of cytochrome c oxidase was demonstrated in the cultured skin fibroblasts and biopsied muscle. In an electron-microscopic study of biopsied muscle, two patients with mitochondrial myopathy were found. Their fundamental enzymatic defects were unclear. In two patients, in whom Leigh's disease was suspected following a brain CT, the production of 14CO2 from [3-14C] pyruvate was found to be low; suggesting a reduced activity of the TCA cycle. In another 18 patients, the fundamental defect was not clear. [ABSTRACT FROM AUTHOR]

The biochemical and therapeutic responses to dietary therapy were studied in a 25-month-old girl and a 1-month-old girl with methylmalonic acidemia (MMA-emia), which was unresponsive to vitamin B12. The minimum daily intake of protein which patients could tolerate and display a good development was between 1.0 and 1.2 g per kg body weight. Supplementation with amino acid mixture devoid of toxic amino acids was required to prevent protein malnutrition when daily protein intake was restricted to 0.6 g per kg body weight. Caloric intake should be sufficient, not only to promote growth but also to prevent a rise in MMA level, especially when a patient has ketoacidosis. It was found that MMA excretion per mg creatinine in random urine specimens correlated significantly with serum MMA and twenty four-hour output of MMA per kg body weight. Therefore measurement of MMA in a single urine specimen is useful for evaluating the in vivo accumulation of MMA. [ABSTRACT FROM AUTHOR]

Two children are described who suffered from episodes of metabolic acidosis and progressive mental and motor deterioration. The patients showed periodic elevation of blood lactate, pyruvate and alanine, which was accompanied by vomiting, hypotonia or convulsions. The concentrations of lactate and pyruvate in cerebrospinal fluid were found to be increased. Liver biopsies revealed a decrease in pyruvate carboxylase activity and normal pyruvate decarboxylase activity. No inhibitor of TPP-ATP phosphoryl transferase was detected in urine from the patients. These findings suggest that congenital lactic acidosis due to pyruvate carboxylase deficiency is probably a different disease entity from Leigh's encephalomyelopathy. A possible mechanism of brain damage caused by a defect in pyruvate carboxylase is postulated. [ABSTRACT FROM AUTHOR]

The article cites a study which reports that aminophylline is effective on acute exacerbations of asthma in adults. Intravenous administration of aminophylline, a theophylline derivative, has been used to relieve acute exacerbations of bronchial asthma for more than 50 years. Despite confidence in its effectivcness, the efficacy of aminophylline in an asthma attack has become controversial. The subjects were 53 adult asthmatic patients (27 males and 26 females). Either aminophylline or salbutamol were randomly selected as initial treatment for an asthma attack.

Nonketotic hyperglycinemia (NKH) is caused by a mutation in the genes encoding the components of the glycine cleavage multi-enzyme system. More than 80% of the patients have defects in the gene encoding P-protein, whereas the rest of the patints have defects in the gene encoding T-protein. We have found a large Israeli-Arab kindred with NKH. At least 14 children were affected, and all the patients had seizures and respiratory failure within 2 days after birth. Enzymatic analysis revealed that T-protein activity was deficient in the liver specimen from one propositus. We screened this family for a mutation in the protein-coding region and exon/intron boundaries of T-protein gene by direct sequencing analysis. A missense mutation was found in exon 2; this resulted in an amino acid substitution from histidine to arginine at position 42 (H42R). Histidine 42 is conserved in human, bovine, chicken, pea, and Escherichia coli, suggesting that it has an important role in catalytic functions. Genotype analyses of 26 family members confirmed that the homozygous H42R mutation was completely associated with the onset of NKH. The availability of DNA testing facilitates the prenatal diagnosis of NKH and the identification of carriers, which is necessary for genetic counseling in the affected families. [ABSTRACT FROM AUTHOR]

For three weeks, male Sprague-Dawley rats at either four weeks (young) or eight months (adult) of age were pairfed one of the purified diets free of or containing either 0.2% of oxidized cholesterol mixture (cholesterol oxidation products) or 0.2% of cholesterol. Although the food intake was similar, dietary oxidized cholesterol lowered body weight gain in young rats, but did not increase relative liver weight, in contrast to the enlargement seen with dietary cholesterol. Oxidized cholesterol, compared to cholesterol, tended to reduce the activity of hepatic 3-hydroxy-3-methylglutaryl CoA reductase and cholesterol 7α-hydroxylase, particularly the latter in aged rats, and prevented the rise in the concentration of liver cholesterol at both ages. It also tended to increase the activity of hepatic δ6 desaturase, particularly in young rats. Moreover, oxidized cholesterol in relation to cholesterol influenced liver and serum lipid concentrations in different ways, and increased lipid peroxidation at both ages. The ratio of splenic CD4/CD8 T-lymphocytes increased with age, but the influence of cholesterol and oxidized cholesterol was comparable. Thus, oxidized cholesterol may specifically disturb growth and age-related changes in the lipid metabolism in rats. [ABSTRACT FROM AUTHOR]

Abstract Pyridoxine-dependent epilepsy is a disease inherited as an autosomal recessive trait, characterized by rapid response to pharmacological dosages of pyridoxine. The defect has been suggested to reside in glutamate decarboxylase (GAD), since a mutant GAD with an abnormally high K[sub m] for a cofactor, pyridoxal phosphate, could not synthesize an adequate amount of gamma-amino butyric acid [Scriver and Whelan (1969) Ann NY Acad Sci 166: 83]. To test this hypothesis, we studied two affected families by screening for mutations in the GAD mRNA and by analyzing a polymorphic marker in the GAD gene. Since two forms of GAD, GAD65 and GAD67, have been identified in human brain, we analyzed both forms. To overcome the limited accessibility of brain tissues, we utilized the minute amounts of GAD mRNAs ectopically transcribed in lymphoblasts. The ectopic GAD transcripts were amplified by reverse-transcription-mediated, nested polymerase chain reaction for mutation analysis. Two and three base substitutions were found in GAD65 and GAD67 cDNAs, respectively. All of them were, however, polymorphisms that were also found in control subjects. We then examined a (CA) repeat polymorphism in the GAD65 gene and found that different maternal alleles were transmitted to two affected sibs in one family. Thus, an etiological mechanism other than a K[sub m] mutant GAD is responsible for pyridoxine-dependent epilepsy. [ABSTRACT FROM AUTHOR]

C57BL/6 (B6) mice were injected I.v. with class I H-2-disparate B10.QBR spleen cells (10/mouse). This regimen, termed donor alloantigen-specific I.v. pre-sensltizatlon (DSP), Induced almost complete reduction of the antl-B10.QBR mixed lymphocyte reaction (MLR) that has been regarded to represent a cytotoxlc T lymphocyte (CTL)-lndependent graft rejection pathway. Because the DSP regimen failed to affect the generation of CTL responses, It did not prolong graft survival. Repeated (four or 11 times) administration (during 5 or 18 days) of rapamycin at suboptimal doses (0.5–2.0 mg/kg/day) failed to eliminate the capacities to exhibit MLR as well as to generate CTL responses. The suppression of CTL responses was achieved only through the combination of these two treatments. It was also shown that prolongation of skin graft survival was not induced by either of a single DSP or rapamycin treatment alone, but by the combination of these. Potent suppression of CTL responses was also induced when a single DSP was combined with repeated injection of a suboptimal dose (0.75 mg/kg/day) of another Immunosuppresslve drug, FK506, Instead of rapamycin. However, there was a substantial difference in cellular mechanisms underlying the suppression of CTL responses by the above two different combinations. Under conditions in which lymphold cells from mice receiving the treatments with DSP plus FK506 failed to generate CTL responses, the addition of recomblnant IL-2 (rlL-2) to cultures restored the CTL generation, suggesting that CTL precursors themselves are not attenuated by the combined treatment. In contrast, the addition of rlL-2 to cultures of lymphold cells from mice receiving the treatments with DSP plus rapamycin failed to increase the generation of CTL responses. These results indicate that (I) DSP capable of eliminating a CTL-Independent graft rejection pathway fails to suppress a CTL-involved pathway, because both CTL precursors and CTL helpers are DSP resistant; (II) the administration of suboptimal doses of rapamycin alone Is not sufficient for the suppression of CTL responses; and (III) the combination of DSP with rapamycin treatment can reduce CTL responses through attenuation of CTL precursors, thus resulting in the prolongation of graft survival. [ABSTRACT FROM PUBLISHER]