Retrospective comparison of 'Cheno' and 'Urso' in the medical treatment of gallstones.

In two groups of gallstone patients ideally suited for medical treatment, the effect of six to 18 months' therapy was compared retrospectively in 52 given chenodeoxycholic acid (CDCA) and 46 given ursodeoxycholic acid (UDCA). The minimum dose (mg kg-1 day-1) required to desaturate bile consistently was 10.1 for UDCA and 14.3 for CDCA. In patients completing six months' treatment, 23 of 35 (66%) taking a mean of 7.7 (+/- SEM 0.5) mg UDCA and 34 of 42 (81%) taking 14.7 +/- 0.2 mg CDCA showed partial or complete dissolution of gallstones. The mean dose in the UDCA-treated patients, however, was artefactually lowered by previous dose-response studies: in those who had not taken multiple doses, the mean UDCA intake in the 'responders' at six months was 9.1 +/- 0.3 mg kg-1 day-1. At six months, more UDCA (five of 35 or 14.3%) than CDCA (four of 42 or 9.5%)-treated patients showed complete dissolution of gallstones, but, by one year, the situation was reversed, 20 of 41 (49%) CDCA-treated and eight of 30 (27%) UDCA-treated patients showing complete dissolution of gallstones. Cumulative efficacy at one year had risen to 76% for UDCA and 89% for CDCA. Both treatments reduced the frequency of dyspepsia and biliary colic; 37% of CDCA and 2.6% of UDCA-treated patients showed hypertransaminasaemia; diarrhoea developed in 60% of the CDCA group but in none of the UDCA group.     

Dominant thalassemia-like phenotypes associated with mutations in exon 3 of the beta-globin gene.

Mutations producing beta-thalassemia reach individual gene frequencies greater than .01 in malarial-endemic regions because beta-thalassemia trait individuals have increased genetic fitness over that of normal individuals. Exon 3 of the beta-globin gene has been relatively spared as a site of common beta-thalassemia mutations. Frameshifts caused by the loss of a single nucleotide and nonsense mutations produce beta-thalassemia trait when they occur in exons 1 and 2. In contrast, they usually produce chronic hemolytic anemia when present in exon 3. Certain missense mutations in exon 3 produce unstable globins and thalassemia intermedia with hemolysis in heterozygotes. Here we report two new mutations in exon 3 of the beta-globin gene. One is a single nucleotide deletion in codon 109 in a 78-year-old Lithuanian with chronic hemolytic anemia and features of thalassemia. It leads to an abnormal globin (beta Manhattan) that is elongated to 156 amino acids. The second is a CAG-CGG missense mutation at codon 127 that causes a Gln----Pro substitution (beta Houston) and a thalassemia intermedia with hemolysis in three generations of a British-American family. Although the clinical phenotypes of these two patients differed little, differences in globin-synthetic ratios were significant, presumably reflecting differences in the ability of each abnormal beta-globin to form alpha beta dimers. The paucity of high-frequency exon 3 mutations and their worldwide distribution is likely attributable to their phenotypic severity and loss of increased genetic fitness vis-a-vis malaria.     

Transforming growth factor-beta trans-modulates the expression of colony stimulating factor receptors on murine hematopoietic progenitor cell lines

Transforming growth factor beta (TGF-beta) is a potent and selective growth inhibitor of early hematopoietic progenitors and leukemic cells. The cellular mechanism(s) underlying this antiproliferative effect is, however, currently unknown. In the present study, we demonstrate that TGF-beta inhibits the expression of granulocyte-macrophage colony stimulating factor (GM-CSF), interleukin 3 (IL-3), and granulocyte-CSF (G-CSF) receptors on murine factor-dependent and independent hematopoietic progenitor cell lines without a significant change in receptor affinity. A maximum reduction in GM-CSF receptor numbers of 65% to 77% was observed by 96-hour incubation with TGF-beta. The TGF- beta induced trans-down-modulation of GM-CSF receptors was prolonged, noncytotoxic but reversible, and not due to endogenous production of GM- CSF. The TGF-beta induced reduction in CSF receptor numbers preceded TGF-beta's growth inhibitory action. In addition, the ED50 (1 to 10 pmol/L) for TGF-beta's CSF receptor modulatory and antiproliferative effect was similar. The effect of TGF-beta on cell surface CSF receptor expression was specific, because the expression of other cell surface proteins (Ly 5 and Ly 17) was not affected by TGF-beta treatment, and because other growth inhibitors (tumor necrosis factor and interferon) did not affect CSF receptor expression. These data suggest that the downregulation of the growth of hematopoietic progenitor cells by TGF- beta involves reducing the cell surface expression on growth factor receptors.     

A behavioral screen for isolating zebrafish mutants with visual system defects.

Optokinetic and phototactic behaviors of zebrafish larvae were examined for their usefulness in screening for recessive defects in the visual system. The optokinetic response can be reliably and rapidly detected in 5-day larvae, whereas the phototactic response of larvae is variable and not robust enough to be useful for screening. We therefore measured optokinetic responses of mutagenized larvae as a genetic screen for visual system defects. Third-generation larvae, representing 266 mutagenized genomes, were examined for abnormal optokinetic responses. Eighteen optokinetic-defective mutants were identified and two mutants that did not show obvious morphological defects, no optokinetic response a (noa) and partial optokinetic response a (poa), were studied further. We recorded the electroretinogram (ERG) to determine whether these two mutations affect the retina. The b-wave of noa larvae was grossly abnormal, being delayed in onset and significantly reduced in amplitude. In contrast, the ERG waveform of poa larvae was normal, although the b-wave was reduced in amplitude in bright light. Histologically, the retinas of noa and poa larvae appeared normal. We conclude that noa larvae have a functional defect in the outer retina, whereas the outer retina of poa larvae is likely to be normal.     

Detection of the hemoglobin E mutation using the color complementation assay: application to complex genotyping

The color complementation assay (CCA) is a method of allele-specific DNA amplification by which competitive priming and extension of fluorescently labeled oligonucleotide primers determine the color of DNA amplification product. This diagnostic method precludes the need for radioisotopes, electrophoresis, and multiple high-stringency reaction conditions. The multiplicity of mutant globin genes present in Southeast Asians complicates clinical diagnosis and underscores the importance of DNA-based diagnostic methods. We have applied CCA to distinguish beta A and beta E alleles. Competing 15mer primers were a fluorescein-labeled complement to beta A and a rhodamine-labeled complement to beta E, identical except for their central nucleotides. A common unlabeled primer was used to amplify DNA product, the color of which was determined by the perfectly complementary primer. Color photography and spectrofluorometry, as well as a method of black-white photography that we developed to distinguish fluorescein- and rhodamine- labeled DNA, were used to record results. We applied CCA to define the complex genotype of a Thai woman with thalassemia intermedia, 96% HbE, and 4% HbF whose possible genotypes included several permutations of alpha-thalassemia, beta-thalassemia, and beta E genes. zeta-Globin gene mapping of DNA doubly digested with Bg/II and Asp 718 showed the -alpha 3.7/--SEA genotype, and CCA confirmed homozygous beta E/beta E. The CCA is useful for diagnosing the compound hemoglobin genotypes of Southeast Asians and could be applied also to prenatal diagnosis in this population.     

DLA-identical bone marrow grafts after low-dose total body irradiation: the effect of canine recombinant hematopoietic growth factors

Previous studies found that bone marrow (BM) allografts from DLA- identical littermates resulted in survival of two thirds of recipient dogs after otherwise lethal doses of 450 to 600 cGy of total body irradiation (TBI) because of successful allografts or autologous recovery after rejection of the allografts. The current study asked whether survival could be further improved by treating allograft recipients with recombinant canine granulocyte colony-stimulating factor (G-CSF), stem cell factor (SCF), or G-CSF/SCF. Of 21 dogs, 14 (67%) receiving allografts but no growth factors survived, 10 with successful allografts (including 5 mixed chimeras) and 4 with autologous recovery; whereas 7 animals died, 5 from infections during BM aplasia and 2 from acute graft-versus-host disease. By comparison, 30 of 34 dogs (88%) receiving hematopoietic growth factors in addition to the BM graft survived, 17 with successful allografts (including 10 mixed chimeras) and 13 with autologous recovery; whereas 4 died, all with infection related to BM aplasia after rejection of the allograft. Survival was similar for recipients of G-CSF, SCF, or the combination of G-CSF and SCF. Logistic regression analyses, which accounted for possible effects of TBI dose, showed a trend for improved survival in dogs receiving growth factors (P = .09), no change in allogeneic engraftment (P = .74), and a slight increase in autologous recovery (P = .22). In agreement with previous data, we found that grafts of BM from DLA-identical littermates improved survival of recipient dogs exposed to low but otherwise lethal doses of TBI. A further improvement in survival could be achieved by additional treatment with G-CSF, SCF, or G-CSF/SCF. Results suggest that treatment by hematopoietic growth factors along with BM grafts should be considered for victims of radiation accidents.     

Silent cerebral infarction,income, and grade retention among students with sickle cell anemia

Children with sickle cell anemia have a higher‐than‐expected prevalence of poor educational attainment. We test two key hypotheses about educational attainment among students with sickle cell anemia, as measured by grade retention and use of special education services: (1) lower household per capita income is associated with lower educational attainment; (2) the presence of a silent cerebral infarct is associated with lower educational attainment. We conducted a multicenter, cross‐sectional study of cases from 22 U.S. sites included in the Silent Infarct Transfusion Trial. During screening, parents completed a questionnaire that included sociodemographic information and details of their child's academic status. Of 835 students, 670 were evaluable; 536 had data on all covariates and were used for analysis. The students' mean age was 9.4 years (range: 5–15) with 52.2% male; 17.5% of students were retained one grade level and 18.3% received special education services. A multiple variable logistic regression model identified that lower household per capita income (odds ratio [OR] of quartile 1 = 6.36, OR of quartile 2 = 4.7, OR of quartile 3 = 3.87; P = 0.001 for linear trend), age (OR = 1.3; P < 0.001), and male gender (OR, 2.2; P = 0.001) were associated with grade retention; silent cerebral infarct (P = 0.31) and painful episodes (P = 0.60) were not. Among students with sickle cell anemia, household per capita income is associated with grade retention, whereas the presence of a silent cerebral infarct is not. Future educational interventions will need to address both the medical and socioeconomic issues that affect students with sickle cell anemia. Am. J. Hematol. 89:E188–E192, 2014. © 2014 Wiley Periodicals, Inc.