Normal and occluded mediastinal veins: MR imaging

The potential of magnetic resonance (MR) imaging to demonstrate the mediastinal veins was evaluated retrospectively in 25 patients with no evidence of a venous abnormality, 28 patients who had narrowing or occlusion of a mediastinal vein, and two patients who had a venous anomaly. In patients with venous occlusion, the MR images graphically demonstrated the sites and extent. MR images also demonstrated slow flow within venous structures proximal to the obstruction. Generally, venous collaterals in the mediastinum and chest wall were better seen with contrast material-enhanced computed tomography scans. The marked contrast on MR images between the signal void of normal vascular structures, the moderate signal intensity of tumor, and the high signal intensity of a thrombus or slowly flowing blood allows ready detection of venous occlusion and may suggest the nature of the occlusion.     

Comparison of anti-Tac and anti-transferrin receptor-conjugated liposomes for specific drug delivery to adult T-cell leukemia

Adult T-cell leukemia (ATL) is a rapidly progressive and usually fatal malignancy of mature T cells characterized by the expression of large numbers of interleukin-2 (IL-2) receptors on the cell surface. Anti- Tac, a monoclonal antibody directed against the IL-2 receptor, was conjugated to liposomes and compared with anti-transferrin receptor (anti-TFR) conjugates for specific binding, internalization, and intracellular drug delivery to ATL cells. Two independent assays were used: a fluorimetric assay with liposome encapsulated 1-hydroxypyrene- 3,6,8-trisulfonic acid, a pH-sensitive fluorescent dye, and a growth inhibition assay using methotrexate-gamma-aspartate, a liposome- dependent cytotoxic drug. MT-1 and HUT-102 cell lines derived from patients with ATL were compared with Molt-4, a leukemia cell line that does not express IL-2 receptors in an uninduced state. Fluorimetric studies showed specific binding and internalization of anti-Tac- conjugated liposomes by HUT-102 and MT-1 but not by the Tac-negative cell line Molt-4, demonstrating the lack of nonspecific or Fc receptor- mediated uptake. Anti-TFR-conjugated liposomes were effectively bound and internalized by all three cell lines and consistently showed the highest degree of cellular liposome uptake. Drug-containing liposomes conjugated to anti-Tac were more than tenfold more effective in causing growth inhibition of ATL cells than the nonspecific control conjugates. Anti-Tac conjugates caused minimal growth inhibition of Molt-4 cells over the concentration range effective against the ATL cells. Anti-TFR- coupled liposomes gave better growth inhibition of HUT-102 and MT-1 cells (40- to 60-fold) than anti-Tac conjugates. Both anti-Tac-directed and anti-TFR-directed liposomes are effective for intracellular drug delivery to ATL cells and may represent a useful method of treatment in this disease.     

Parental SCN1A mutation mosaicism in familial Dravet syndrome

Different SCN1A mutations are known to cause a variety of phenotypes, such as generalized epilepsy with febrile seizures plus (GEFS+), Dravet syndrome and familial hemiplegic migraine (FHM). In Dravet syndrome, most mutations are de novo and familial cases are rare. In this study, Dravet syndrome is observed in two maternal half sisters. They have healthy fathers and their common mother has never experienced seizures, but has a lifelong history of migraine. Direct sequencing of DNA extracted from blood revealed a heterozygous SCN1A nonsense mutation c.3985C>T in the sisters, but not in the mother. The mutation induces a premature stop codon and probably leads to a non-functional protein. Further examination of the mother's DNA showed that she has a mosaicism of the mutation. This report of parental SCN1A nonsense mutation mosaicism in familial Dravet syndrome suggests that mosaicism might be more common than previously suspected and emphasizes the importance of taking mosaicism into account in genetic counselling of Dravet syndrome and SCN1A mutations. Furthermore, whether the migraine of the mother could be influenced by her SCN1A mutation mosaicism is not known, but increased awareness of migraine in future studies of SCN1A related epilepsies could clarify this intriguing link between migraine and epilepsy.     

"A Free thenar flap – A case report"

We present a case report of a free thenar flap surgery done for a volar right hand middle finger, distal and middle phalanx degloving injury. A free thenar flap is a fasciocutaneous sensate flap supplied by a constant branch of the superficial radial artery and its variable nerve supply. It has a distinct advantage of low donor site morbidity, better cosmesis and texture of the flap. No immobilization is required postop. The donor site can be closed primiarily.     

Hepatitis B e antigen negative chronic hepatitis in Indian patients : A reality

Background: Hepatitis B e antigen negative chronic hepatitis (e⁻ CHB) with detectable levels of hepatitis B virus DNA (HBV DNA) in serum has been reported in cases from Asia. This study was undertaken to find out prevalence e⁻CHB and to correlate its presence with the clinical status and severity of the illness in cases of chronic liver disease in India.