Hemoglobin Constant Spring

Hb constant spring (HbCS) is an abnormal hemoglobin characterized by a mutation of the a2-globin gene termination codon that produces an elongated a-chain. HbCS occurs in South China, Southeast Asia, and the Mediterranean region. The carrier frequency is estimated to be 5% in northeast Thailand and Laos and it is the most prevalent nondeletional a-thalassemia in Southeast Asia.

Asymptomatic heterozygous HbCS is difficult to detect by standard electrophoresis, as HbCS levels are less than 1% of total hemoglobin. In contrast, the homozygous state causes hemolytic anemia; HbCS levels are often 6-8% of total hemoglobin and Hb Bart's (see Chapter ?) is about 1-2%. The diagnosis should be suspected in individuals (especially from high-risk ethnic groups) who have mild anemia, minimal microcytosis, nucleated RBCs, marked basophilic stippling on blood smear, low (<2%) HbA2 levels, or persistent Hb Bart's. Southern analysis (e.g., reverse dot blot format) using allele-specific probes for the a2-chain termination mutants will confirm the diagnosis. More recently, simplified PCR assays for HbCS have been developed.[13]

Getting Started With Dumbbells

Getting Started With Dumbbells

The use of dumbbells gives you a much more comprehensive strengthening effect because the workout engages your stabilizer muscles, in addition to the muscle you may be pin-pointing. Without all of the belts and artificial stabilizers of a machine, you also engage your core muscles, which are your body's natural stabilizers.

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