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S R Kumar

Publications and source records attributed to S R Kumar.

26 records · Page 2Linked to original sources
PubMed1988

In vitro differentiation of quail neural crest cells into sensory-like neuroblasts.

This study shows that quail neural crest cells can differentiate in vitro into sensory-like neuroblasts. The putative sensory neuroblasts were large and spherical, possessing large diameter, bipolar or pseudo-unipolar, long processes that lacked multiple varicosities characteristic of autonomic neurons. They bound HNK-1, a monoclonal antibody against a cell surface epitope expressed by early neural crest cells but not by young neural tube-derived cells. Many of the sensory-like neuroblasts had substance P (SP)-like immunoreactivity. Some exhibited histochemical carbonic anhydrase activity; carbonic anhydrase is shown in this study to stain a subpopulation of spinal sensory neurons in adult quail and embryos 9 days and older, whereas ventral root axons and neurons in sympathetic ganglia are non-reactive at all ages. Double staining indicated that unlike the multipolar neuroblasts developing in the same cultures, SP-like immunoreactive neuroblasts do not contain detectable levels of tyrosine hydroxylase or dopamine-beta-hydroxylase. Finally, the neuronal nature of the cultured sensory-like neuroblasts was further documented by double labeling for antibodies against the 68 kDa neurofilament polypeptide and substance P.

Animals↗
PubMedDate not supplied

Sickle cell anemia with systemic lupus erythematosus: response to hydroxyurea therapy.

PURPOSE: To report the efficacy of hydroxyurea (HU) in a patient with sickle cell anemia (SCA) associated with systemic lupus erythematosus (SLE). PATIENTS AND METHODS: An unusual association of SCA with SLE occurred in a 14-year-old black girl. Her medical history was significant for repeated vasoocclusive crises requiring repeated hospitalizations and transfusions, acute chest syndrome, hyperhemolytic crises, multiple transfusions resulting in iron overload, gall stones, avascular necrosis, and significant psychosocial problems. Her lupus activity was controlled with oral prednisone and hydroxychloroquine. Treatment with oral HU was instituted at an initial dose of 20 mg/kg with gradual increment to a maximum of 25 mg/kg daily. RESULTS: A dramatic clinical improvement was noted with HU therapy with no episode of pain crisis or hospitalization for 5 months. There was an increase in fetal hemoglobin (HbF) to 20.9% and mean corpuscular volume to 114.5 fl, but her Hb level remained steady at 7.5 g/dl. No toxicity was noted with HU therapy. In addition, a significant change was also observed in her school performance, social activities, and general quality of life. CONCLUSIONS: HU therapy may be beneficial and safe and should be considered for other patients who have SCA with SLE.

Adolescent↗
PubMedDate not supplied

Visual evoked response in macular diseases.

Visual evoked responses (VER) were recorded in 10 patients with unilateral maculopathy. VER latency and amplitude were compared between the affected and unaffected eyes. Evaluation of results reveals that in macular disease with fluid accumulation (Central Serous Retinopathy and Traumatic Macular Oedema) the VER showed amplitude reduction depending on reduced visual acuity with no significant change in latency, whereas, in disease with degeneration of retinal layers, (Degenerative Maculopathy) latency was markedly increased signifying associated conduction defect.

Adolescent↗