Patient with chronic myelogenous leukemia and late appearing Philadelphia chromosome

The sixth example of a late appearing Ph¹ chromosome in a patient with typical chronic myelogenous leukemia is the subject of the present report. Knowledge of the true frequency of this apparently rare event awaits systematic longitudinal cytogenetic studies of patients with Ph¹-negative CML.     

Congenital generalized fibromatosis causing spinal cord compression

An unusual case of congenital generalized fibromatosis in which involvement of the spinal dura mater was accompanied by flaccid paralysis in the lower limbs is presented.     

Converting-enzyme in the choroid plexus, brain, and kidney: immunocytochemical and biochemical studies in rats

In rats, immunoreactivity was demonstrated in the brush border of the choroid plexus, in the wall of blood vessels in the brain, and in the brush border of the proximal tubules of the kidney, using the peroxidase-antiperoxidase technique (PAP) and an anti-pulmonary converting-enzyme antibody. These findings correlate with biochemical data of converting-enzyme activity in the choroid plexus and in other tissues. Possible functions of the enzyme in relation to its localization are discussed.     

Lamina-specific alteration of C-fibre evoked activity by morphine in the dorsal horn of the rat spinal cord

The effect of systemic morphine (5 mg/kg) on the C-fibre evoked activity in the dorsal horn of decerebrate spinalized rats has been investigated. Activity in units recorded from lamina 5 was inhibited in a naloxone-reversible fashion by morphine. However, morphine produced variable changes in the C-evoked activity of units recorded within the substantia gelatinosa, some units showing excitation, some inhibition and some an alteration in the timing and pattern of the C-evoked activity.     

Comparison between developmental and senescent changes in enzyme activities linked to energy metabolism in rat heart

The developmental and senescent patterns of a number of heart enzyme activities linked to energy metabolism have been studied in rats aged between 4 days and 21 months. A morphometric study of mitochondrial volume fractions and numbers has been also carried out. Developmental changes result in a rise of most mitochondrial enzymes (NADP⁺-isocitrate dehydrogenase, malic enzyme, succinate dehydrogenase, citrate synthase) and mitochondrial volume fractions. Exceptions are NAD⁺-isocitarte dehydrogenase, which declines from 4 days onwards, and NAD⁺-malate dehydrogenase, which declines and then rises over the same period. Senescent changes follow two different trends. While pyruvate kinase and those mitochondrial enzymes lying between citrate formation and isocitrate oxidation (citrate synthase, NADP⁺- and NAD⁺-isocitrate dehydrogenases) decline to some degree, mitochondrial succinate dehydrogenase and NAD⁺-malate dehydrogenase activities increase over the same period. This could point towards a partial impairment of Krebs cycle function, and a reduced energy-producing capacity in the aged rat heart.     

Cellular immune response to β2-glycoprotein-I valine/leucine247 phenotypes in Mexican patients with primary antiphospholipid syndrome

Homozygote genotype V²⁴⁷ of the β₂-glycoprotein-I (β₂GP-I) gene has been associated with anti-β₂GP-I and thrombosis in patients with primary anti-phospholipid syndrome APS (PAPS). However, the cellular immune response to β₂GP-I²⁴⁷ has been little studied.

Haplotype block 1 variant (HB-1v) of the NKG2 family of receptors

The natural killer group 2 (NKG2) family of receptors, encoded within the NK complex gene region (NKC), modulate the cytotoxic activity of NK cells. Two haplotype blocks throughout the NKC, hb-1 and hb-2 have been associated with different levels of overall natural cytotoxicity. Here, we evaluated allelic and genotype frequencies at rs1049174, rs2617160, rs2617170, rs2617171, rs1983526 (hb-1 haplotype), and rs2255336 and rs2246809 (hb-2 haplotype) in 928 subjects examined from Mexico City. The most frequent alleles and genotypes were as follows: C, CG to rs1049174; G, GG to rs2255336; T, AT to rs2617160; G, GG to rs2246809; C, CT to rs2617170; G, CG to rs2617171; and G, CG to rs1983526. Linkage disequilibrium analysis revealed that rs1049174, rs2617160, rs2617170, and rs2617171 constituted the haplotype block-1 variant (hb-1v) (r² ≥ 0.89). Two predominant haplotypes of hb-1v were identified based on the allele content and included CTCG and GATC. This study is the first to evaluate the allelic and genotype frequency distribution of rs1049174, rs2255336, rs2617160, rs2246809, rs2617170, rs2617171, and rs1983526 in the population of Mexico City.     

Genetic and cytogenetic studies in children with retinoblastoma

Genetic and cytogenetic studies were performed in 110 children with retinoblastoma (57 girls and 53 boys), with 70% of cases being unilateral and 30% bilateral. The mean age of the patients at diagnosis was 22.6 months in unilateral and 11.1 months in bilateral cases. Sporadic cases were 94.5%, and the remaining were familial. There was no difference when the paternal age of sporadic cases was compared with that of familial cases. Three patients from a family exhibiting unilateral retinoblastoma had an interstitial deletion at band 13q14. The presence of other neoplasms and the importance of the genetic and chromosomic studies, for the purpose of genetic counseling, are discussed.     

Cytogenetic studies in a case of T-cell prolymphocytic leukemia

The authors describe cytogenetic aberrations observed in a case of T prolymphocytic leukemia. C11 deletion (q14) B5 deletion (pter), D14q⁺, E20 trisomy, and two markers are the main anomalies of the complement.     

The role of T-agglutinin in the disappearance of erythrocytes artificially aged by desialylation

The chance discovery of two mouse strains, one with and one without a high presence of serum T-agglutinin, permitted the investigation of the role of this antibody in the disappearance of desialylated erythrocytes, which may be regarded as a model for ageing. The proportional relationship between the quantity of sialic acid removed and the diminution of half-life is not affected by the presence or absence of T-agglutinin. Opsonization by T-agglutinin would therefore appear to be an improbable mechanism. Other possible theories are discussed.     

The damage of the hepatic mixed functional oxygenase system by CCl4: significance of incorporation of 14CCl4 metabolites in vivo

The relation between incorporation of ¹⁴C from ¹⁴CCl₄ into liver lipids and damage to the mixed functional oxygenase system of liver microsomes was investigated in rats of different sex or differently pretreated. Under the respective conditions of pretreatment the ¹⁴C incorporation rate and the relative decrease of the cytochrome P-450 level as the parameters most influenced by CCl₄ were compared with those for untreated female rats. Induction by 3-methylcholanthrene does not after both parameters. Induction by sodium phenobarbital enhances the ¹⁴C incorporation rate as well as the cytochrome P-450 decrease but the latter is more affected. In male rats only the ¹⁴C incorporation rate increased. Vitamin D₃-pretreated rats showed a smaller decrease of cytochrome P-450 but an enhanced ¹⁴C incorporation rate. Therefore, there is no correlation between the cytochrome P-450 decrease and ¹⁴C incorporation rate. Reasons for the lack of that correlation are discussed with regard to the mechanism of liver cell damage by carbon tetrachloride.     

Changes in serotonin receptors in different brain regions after light exposure of dark-reared rats

Male rats dark-reared from birth until 50 days of age and then exposed to light for 3 h show significant increases in specific [³H]serotonin (5-[³H]HT) binding to P₂ membranes from visual and motor cortex and superior colliculus (25, 65 and 23% respectively) as compared with normal and dark-reared littermates. These increases are transient and return to normal levels after 7 days. The role of 5-HT as a transmitter in the visual system is discussed.     

Cell-mediated immunity in leprosy and transfer of delayed hypersensitivity reactions

Eighty-nine patients with leprosy, 65 classified as lepromatous and 24 as tuberculoid, were examined in this study. Skin test responses to protein antigens and dinitrochlorobenzene (DNCB) were depressed in lepromatous patients compared to controls. Tuberculoid patients did not exhibit a significant depression to microbial antigens, but they showed a definite depression in the ability to be sensitized with DNCB. The transfer of delayed hypersensitivity reactions to tuberculin, trichophytin, and lepromin (Fernandez and Mitsuda reactions) was accomplished in lepromatous and indeterminate leprosy patients using viable lymphocytes from donors presenting positive reactions to these antigens. The lepromin reaction was also transferred to patients with South American blastomycosis and cutaneous leishmaniasis. The positive reactions of adoptive immunity were confirmed by histologic examination of skin biopsies.     

Presence of kappa 2 light chain in normal rabbits and as induced auto anti-allotype antibody in kappa 1 light chain suppressed subjects

Using an antiserum raised in b(bas)/b(bas)-suppressed rabbits to kappa 2 light chain we have shown that the kappa 2 light chain is an isotype of kappa 1, present in the majority of, if not all, rabbits. It probably exists in at least 2 allelic forms. It is capable of producing a functional antibody molecule (auto anti-b6) and compensates for the absence of kappa 1 light chain in homozygous b6-suppressed rabbits.     

Age-dependence of polyadenylate stimulation of nuclear-envelope nucleoside triphosphatase

Nuclear envelopes of mammalian cells contain a nucleoside triphosphatase which is probably involved in mRNA transport through the nuclear membrane. The activity of the enzyme, studied in RNA-depleted nuclear ghosts, can be stimulated by poly(A) or by poly(A) (+)mRNA. Using nuclear ghost preparations from mature (8–10 months' old) and old (40–42 months' old) Wistar rats, it was shown that in “old” preparations the basal activity of the enzyme is significantly reduced (by 15%). In addition, the enzyme from old animals responds only very little to poly(A) or poly(A) (+)mRNA, compared to preparations from mature animals. Using a concentration of 6.8 × 10¹¹ poly(A) (+)mRNA molecules per μg of enzyme preparation, the nucleoside triphosphatase from mature animals is stimulated by 77% and the enzyme from old animals by only 26%.

Binding studies of poly(A) to pore laminae revealed that the number of binding sites in unphosphorylated preparations from old animals is significantly reduced (by 24%) compared to “mature” preparations. As a consequence of in vitro phosphorylation, no difference is observable in the number of binding sites between the two age groups. The values for half-maximal saturation binding constants for poly(A) are identical in unphosphorylated and phosphorylated pore-laminae preparations, irrespective of the age group studied. The results presented indicate that in old animals the pathway from the phosphorylated to the dephosphorylated nuclear-envelope protein which is controlled by poly(A) is impaired in the proposed cycle for mRNA efflux from nuclei.