Diagnosis of concurrent hemoglobin H disease and heterozygous beta-thalassemia.
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Definitive diagnosis of concurrent hemoglobin (Hb) H disease and heterozygous beta-thalassemia cannot be made from Hb analysis alone, but necessitates genotype analysis and family study. Interactions between alpha- and beta-thalassemia must be considered when investigating moderate to severe hypochromic microcytic anemia of uncertain cause in adult patients from areas with a high prevalence of globin gene mutations. (+info)
Nitrogen starvation-induced chlorosis in Synechococcus PCC 7942. Low-level photosynthesis as a mechanism of long-term survival.
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Cells of the non-diazotrophic cyanobacterium Synechococcus sp. strain PCC 7942 acclimate to nitrogen deprivation by differentiating into non-pigmented resting cells, which are able to survive prolonged periods of starvation. In this study, the physiological properties of the long-term nitrogen-starved cells are investigated in an attempt to elucidate the mechanisms of maintenance of viability. Preservation of energetic homeostasis is based on a low level of residual photosynthesis; activities of photosystem II and photosystem I were approximately 0.1% of activities of vegetatively growing cells. The low levels of photosystem I activity were measured by a novel colorimetric assay developed from the activity staining of ferredoxin:NADP+ oxidoreductase. Photosystem II reaction centers, as determined by chlorophyll fluorescence measurements, exhibited normal properties, although the efficiency of light harvesting was significantly reduced compared with that of control cells. Long-term chlorotic cells carried out protein synthesis at a very low, but detectable level, as revealed by in vivo [35S]methionine labeling and two-dimensional gel electrophoresis. In conjunction with the very low levels of total cellular protein contents, this implies a continuous protein turnover during chlorosis. Synthesis of components of the photosynthetic apparatus could be detected, whereas factors of the translational machinery were stringently down-regulated. Beyond the massive loss of protein during acclimation to nitrogen deprivation, two proteins that were identified as SomA and SomB accumulated due to an induced expression following nitrogen reduction. (+info)
Immunological measurement of transferrin compared with chemical measurement of total iron-binding capacity.
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Because of uncertainty as to the molecular weight of transferrin, a previous comparison [Von der Heul et al., Clin. Chim. Acta 38, 347 (1972)] between transferrin content of serum and total iron-binding capacity cannot be definitive. We found a conversion factor for expressing the maximum amount of iron bound by 1 mg of transferrin. We compared the resulting calculated value with values obtained by three other methods for measuring total iron-binding capacity. We agree with the previous observation that the latter, as measured radioisotopically, give higher results than would be judged from the transferrin content but the same as those for two chemical methods. The diffusion rate of transferrin in agar was the same irrespective of the degree of iron saturation. Serum transferrin concentrations were low in patients with anemia resulting from malignancy, chronic disorders, and cirrhosis of the liver, and high or normal in patients with iron deficiency anemia and in pregnant women or women who were taking birth-control pills. Measurement of transferrin concentration can be used to distinguish iron deficiency anemia from anemia resulting from chronic disorders, but offers no advantages over existing methods for estimating total iron-binding capacity. (+info)
Erythrocyte protoporphyrin in the detection of iron deficiency.
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Any decrease in the availability of iron for incorporation into the heme moieties of hemoglobin results in an increase in the erythrocyte protoporphyrin concentration. Our aim was to compare protoporphyrin concentrations, determined spectrophotometrically, with body iron stores, as assessed from the amount of iron demonstrable by Prussian blue staining of bone marrow aspirates. The mean protoporphyrin concentration (175 mu-g/dl) in the erythrocytes of a group of patients with markedly decreased stainable marrow iron or no iron was significantly greater (P less than .001) than the mean concentration (76 mu-g/dl) in a comparable group with adequate bone marrow iron stores, except in the presence of certain interfering conditions. These results suggest that the erythrocyte protoporphyrin test may be a useful addition to the methods now available for assessing disorders of heme synthesis, the most common of which is iron deficiency. (+info)
Zinc deficiency occurring in females. Report of two cases.
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The syndrome of dwarfism, hypogonadism, iron-deficiency anemia and geophagia, first reported in 1960 from Iran, was thought to be limited to males. In 1971-1972 two females with the same clinical features were observed over a 14-month period. The anemia responded rapidly to iron. Growth and sexual development occurred promptly when 120 mg of zinc sulfate was administered daily in conjunction with a well-balanced diet and iron supplement. This diet prior to the addition of zinc sulfate, resulted in gradual but much slower growth and sexual development. Observations in these two patients provide confirmation of the occurrence of human zinc deficiency in females, which responds to large doses of zinc salt. (+info)
Erythrocyte volume distribution in normal and abnormal subjects.
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Size-frequency distribution curves of erythrocytes were generated with the Coulter Counter in 73 normal subjects and patients. Mean corpuscular volume (MCV) determined by routine calculation and MCV determined by size-frequency distribution were similar in all normal subjects and in patients with a single population of erythrocytes. Some patients with iron-deficiency anemia, folate deficiency, and vitamin B12 deficiency had two discrete erythrocyte populations. Some patients with microcytic anemia were shown to have a population of normocytes in addition to the predominant microcytic population. Reticulocytes and normocytes were identified in two patients recovering from macrocytic anemia. Transfused blood was identified as a separate population in a patient with microcytic anemia. In cases with two erythrocyte populations, the MCV of the principal population, as determined from size-distribution curves, differed from the MCV of the entire erythrocyte pool, as was determined by routine methods. Analysis of sequential erythrocyte size distributions in patients under treatment demonstrated the dynamics of erythrocyte subpopulations. Anisocytosis was quantified and shown to be associated frequently with hospitalized patients. (+info)
Radiological changes in pica.
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The significance of pica and geophagia as a public health problem is well known. The objective radiographic diagnosis of geophagia depends on the abnormal opacification of the bowel as an immediate manifestitation of the condition. The chance of detectability of geophagia is highest in the colon and can be improved by using low penetration films, particularly for smaller amounts of ingested clay. Other radiologic changes frequently associated with the prolonged practice of geophagic are an atonic pattern of the colon, secondary radiographic changes due to iron-deficiency anemia and bone-age retardation. The occurrences of intestinal obstruction due to pica in the presence of preexisting bowel stricture is demonstrated. (+info)
Anemia and iron deficiencies among long-term renal transplant recipients.
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Iron deficiency anemia after renal transplantation has not been systematically investigated. The prevalence of anemia and the indicators of iron deficiency among 438 renal transplant recipients were examined. Anemia was present in 39.7% of the patients. The prevalence of iron deficiencies, as indicated by a percentage of hypochromic red blood cells (HRBC) of >or=2.5%, was 20.1%. The majority of severely anemic patients exhibited HRBC values in the upper quartile. Positive associations of hemoglobin levels with creatinine clearance, serum transferrin levels, male gender, transferrin saturation (TSAT), polycystic kidney disease, and age were observed. Negative associations with erythropoietin therapy, use of azathioprine, serum ferritin levels, and body mass index were observed. The risk for anemia was closely related to the highest quartile of HRBC percentages (odds ratio, 2.35; 95% confidence interval, 1.48 to 3.75; P = 0.00029), whereas ferritin levels and TSAT conferred no risk for anemia. Therefore, assessment of the HRBC proportion is superior to decreased ferritin and decreased TSAT measurements for the diagnosis of iron deficiencies among renal transplant recipients. (+info)