Hemoglobin constant spring defined by specific oligonucleotide hybridization and hemoglobin D Punjab (beta 121----Gln) in a Batak Indonesian family

A Batak Indonesian from North Sumatra with hemoglobin (Hb) D Punjab (alpha 2 beta 2 121----Gln) and hemoglobin Constant Spring (Hb CoSp) is described. The 24-year-old man did not have clinical symptoms, and his hematological indices were normal. However, he had a persistent slight elevation of fetal hemoglobin level. His mother and his brother were heterozygous for Hb D Punjab; his father had Hb CoSp trait. A sister did not have any abnormal hemoglobin. To show the exact molecular defect leading to the synthesis of Hb CoSp in this family, genomic DNA from the father was analyzed by hybridization with synthetic oligonucleotides. Genomic DNA was digested with Sst I and Hind III producing a 1.05-kb fragment from the 3' end segment of the alpha 2-globin gene, including the termination codon. Two nonadecamers were synthesized to serve as probes: one, entirely homologous to the normal 3' end of alpha 2A-globin gene sequence, including the termination codon TAA, the other different from it by a replacement of the T in the termination codon TAA with C, changing it to CAA, the codon for the amino acid glutamine. DNA from normal controls gave a positive signal with the normal alpha 2TAA oligonucleotide probe but negative with the alpha 2 CAA probe. The father of propositus who had Hb CoSp trait gave a positive signal with the normal alpha 2TAA oligonucleotide probe as well as with the alpha 2CAA oligonucleotide probe, showing him to be heterozygous for the alpha 2CAA-globin gene. This result shows that the Hb CoSp in the Batak family is indeed due to a replacement of T by C in the TAA termination codon of the alpha 2-globin gene changing it to CAA the condon for glutamine. This explains the resulting readthrough of the untranslated sequence of the mRNA.     

用反相HPLC分析一例HbF变异体—HbF—新疆[~Aγ~T25(B7)Gly→Arg]

在1989年乌鲁木齐市进行的脐带血筛选中,我室又发现了一例异常胎儿血红蛋白(HbF)。理化性质测定证明该变异体为一轻度不稳定Hb。经反相高效液相色谱法(HPLC)等方法测定证明该变异体为HbF-新疆[~Aγ~T25(B7)Gly→Arg]。胡怀钰曾于1986年首次发现该变异体,并命名。与前例比较,本例除分析方法部分不同外,两例先证者的临床症状亦稍有差别。本例的先证者在半岁前患有轻度贫血,而首例先证者未见关于贫血的报道。     

实验性抑郁症大鼠缰核和海马BDNF基因表达

目的：研究抑郁症大鼠缰核和海马BDNF基因的表达情况。方法：采用长期未预知应激刺激致大鼠抑郁症模型，运用open-field和forced swinmming test法观察大鼠行为学变化。运用免疫组化法检测缰核和海马BDNT基因的表达。结果：与正常对照组相比，抑郁症模型组大鼠海马和缰核均表现为BDNF阳性细胞数量明显减少。结论：实验性抑郁症大鼠缰核、海马BDNF基因表达水平降低。     

Time-dependent study of the antibody response to sperm-whale myoglobin: recognition of the antigenic sites is unaltered over an extended period of immunization

We have recently shown that the antigenic structure of sperm-whale myoglobin is not dependent on the host species in which the antisera are raised. The purpose of the present work was to determine whether or not the molecular immune recognition of a protein by antibody is subject to a time-dependency. We have investigated the recognition of the antigenic sites by serial antisera obtained in two rabbits at different times after the initial immunization, from the earliest bleeding with detectable antibodies (9 days) up to a year. The specificity of these antisera was determined by their cross-reactions with 13 myoglobins from different species. The reactivity was measured by quantitative immunoadsorbent titration studies from the amount of radioiodinated antibodies that could be bound maximally (i.e. plateau binding values) by immunoadsorbents of each myoglobin. From these studies and our recent structural analysis, which enabled us to identify for each of these myoglobins the regions retaining reactivity with antibodies to sperm-whale myoglobin, we have concluded that following maturation of the immune response the antigenic recognition of a protein (i.e. the regions that are recognized as antigenic) is not dependent upon the time antisera are obtained after the first immunization. In the early periods of the response, fluctuations are observed in the relative immunodominance of the sites. This further confirms our earlier conclusions that the antigenic sites on a protein are structurally inherent in the protein.     

Rapid molecular characterization of Hb H disease in Chinese by polymerase chain reaction

Summary We have developed a rapid method to molecularly distinguish different types of Hb H disease. The study depended on (a) most of the Hb H disease in Taiwan having an-thalassemia-1 of the Southeast Asia type (-SEA) in one allele and (b) the differences of X box of-globin gene cluster in the other allele. To detect the -SEA allele, we utilized the primers located on either side of the breakpoint to do PCR, then characterized the amplified products. For the other allele, we sequenced part of the X box, and found that bases –2803 to –2461 of the X box of – ^3.7 belonged to the X box of ₂ globin gene. In – ^4.2, the bases belonged to the X box of ₁ globin gene, whereas in ^cs it contained both X boxes of ₁ and ₂ globin genes. There was anMboII site at this region of the X box of ₂ globin gene. We utilized PCR to amplify this region and digested it with restriction enzymeMboII, then combined it with another PCR of different primer pairs to molecularly diagnose different types of Hb H disease. One hundred and one cases of Hb H disease from different families were studied: all of the cases had one allele of -SEA deletion, while the other allele showed that 52/101 were – ^3.7, 41/101 were ^cs , 7/101 were – ^4.2, and 1/101 was – ^G.Taichung. Of 52 cases of Hb H with – ^3.7, 47 were type-I deletion and five were type-II deletion.     

Comparative patterns of i-antigen expression, F-cell frequency and Hb A2 level in acute myeloid leukemia and in acute lymphoid leukemia

Hb F, Hb A₂ and i-antigen expression were investigated in adulthood acute leukemias. The study of i-antigen expression by immuno-agglutination and immunofluorescence showed that it is preferentially increased among AML patients. A similar result was obtained for F-cell frequency which was often increased in AML, while it was normal in ALL. Hb A₂ level was significantly lower in AML than in ALL. These differences between AML and ALL red cell patterns further suggest that the leukemic clone involves the erythroid lineage in AML but not in ALL.     

Effect of short-term administration of lead to pregnant rats.

Lead was administred to adult female rats in drinking water (0;0.1:1 and 10 ppm) for 3 weeks before mating, during pregnancy and during 3 weeks after delivery. On day 21 after delivery the mothers and their newborns were sacrified and various parameters of blood -- lead concentration on (Pb-B), hematocrit (Htc), hemoglobin (Hb), free erythrocyte porphyrins (FEP), delta0aminolevulinate dehydratase (ALAD) -- and tissue -- ALAD, free tissue porphyrins (FTP), lead concentration (Pb-T) -- were determined. In mothers a significant increase in Pb-B and Pb concentration in kidney was found in the 10 ppm group, but this increase in lead concentration was not associated with any statistically significant modification of the biochemical parameters. In newborns, lead concentration in blood and in kidney was also significantly increased in the 10 ppm group and this lead exposure was associated with a decrease of the ALAD activity in blood and an increase of FTP in kidney. On the basis of the biochemical parameters investigated one can therefore conclude that the developing organism is more susceptible to the biological action of lead than the organism of adult animals and that the "no-effect" level of lead administered during pregnancy and in the neonatal period is around 1 ppm.     

Disassociation of carbon disulfide-induced depression of flash-evoked potential peak N166 amplitude and norepinephrine levels.

Exposure to organic solvents frequently causes functional impairment of the central nervous system (CNS). One method to examine the effects of solvent exposure on visual function is flash-evoked potentials (FEPs). Greater knowledge of the role of various neurotransmitters in generating FEP peaks would be beneficial for understanding the basis of neurotoxicant-induced changes. FEP peak N166 is influenced by the psychological construct of arousal, which in turn is believed to be influenced by the function of neurons containing norepinephrine (NE). Because of its known effects on both NE and FEPs, we utilized carbon disulfide (CS2) as a means to examine the possible role of NE in modulating the amplitude of FEP peaks N36 and N166. Our hypothesis was that CS2-induced alterations in cortical NE levels would be correlated with changes in FEP peak N36 and N166 amplitudes. Adult male Long-Evans rats were implanted with electrodes over their visual cortex and allowed to recover. To develop peak N166, FEPs were recorded for two days prior to dosing. On the third day, FEPs were recorded prior to dosing, and one group of animals was sacrificed to serve as pretreatment controls. The remaining animals were dosed ip with 0 (corn oil vehicle; 2 ml/kg), 100, 200, or 400 mg/kg CS2. The treated animals were retested at 1, 4, 8, or 24 h after dosing, immediately sacrificed, and samples of the cortex, cerebellum, striatum, and brain stem were frozen for high performance liquid chromatography (HPLC) analysis of monoamine levels. Treatment with CS2 decreased peak N166 amplitude at 1 h, and peak N36 amplitude was depressed at 4 h, relative to the subject's pretreatment values. Peak latencies were increased, and colonic temperature was decreased by treatment with CS2. Exposure to CS2 depressed NE levels in the cortex, brain stem, and cerebellum 4 h after treatment. Conversely, at 4 h, levels of dopamine (DA) and its metabolite 3,4-dihydroxyphenylacetic acid were increased in the brain stem and cerebellum, and levels of the DA metabolite homovanillic acid were increased in the brain stem. Levels of serotonin were unaffected by CS2 treatment. There was a slight increase in striatal levels of the serotonin metabolite 5-hydroxyindole acetic acid at all times after treatment with CS2. There was no apparent association between the decreases in NE levels and the reductions in amplitudes for peaks N36 and N166. The neurochemical mechanism for CS2-induced reductions in FEP peak amplitudes remains to be determined.     

Hb Manukau [β67(E11)Val → Gly; HBB: c.203T>G]: The Role of Genetic Testing in the Diagnosis of Idiopathic Hemolytic Anemia

The increasing availability of DNA sequencing of globin genes has improved our ability to detect conditions that were presumed to be extremely rare. These conditions may remain undiagnosed due to unfamiliarity with clinical presentation, relative unavailability of advanced diagnostic alternatives, or may defy detection by being electrophoretically silent or extreme instability rendering their presence to be below detection level. Genetic studies were pursued in a mother and daughter with severe hemolytic anemia as initial testing failed to be diagnostic. DNA sequence analysis of the β-globin gene identified Hb Manukau [β67(E11)Val?→?Gly; HBB: c.203T?>?G], an extremely unstable hemoglobin (Hb) variant. This is the second family described with this condition (first in the western hemisphere). An astute clinician may benefit from being persistent and pursuing additional testing including molecular genetic characterization where clinical suspicion remains high.