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L C Yu

Publications and source records attributed to L C Yu.

157 records · Page 9Linked to original sources
PubMed1975

Distribution of blood flow in the intestine with hypertonic glucose in the lumen.

The effects of luminal placement of 50 percent glucose solution on distribution of blood flow within the jejunal wall were studied with radioactive microspheres. Two types of spheres, 15 +/- 5 mu in diameter, were used. One was labeled with cerium- 141 (Ce- 141) and the other with strontium-85 (Sr-85). They were injected sequentially to test for reproducibility of the results. These two types of spheres gave similar results qualitatively and quantitatively. Luminal placement of 50 percent glucose increased total blood flow to the jejunal wall but the increase occurred mainly in the mucosal layer. The flow to the submucosa or muscularis-serosa was not altered. This increased mucosal flow was attenuated by prior exposure of the mucosa to a local anesthetic, dibucaine. It is suggested that the increased intestinal blood flow that occurs in the experimental dumping syndrome is confined to the mucosa of the intestine and is mediated by mechanisms that can be inhibited by exposing the mucosa to a local anesthetic.

Anesthesia, Local↗
PubMed1970

The molecular mechanism of force generation in striated muscle.

An electrostatic mechanism for force generation in muscle is proposed which does not require bond formation between thick and thin filaments nor movement of the cross bridges. The myosin heads, which project from the thick filaments and touch the thin filaments, possess a high negative surface charge density. Owing to their large dielectric increment, the thin filaments are polarized by the electric field generated by the myosin heads. The polarized thin filaments tend to move toward the center of the sarcomere. Myosin ATPase activity is increased in the overlap region to maintain the negative surface potential. Thus, ATP hydrolysis provides the energy for shortening. Calculations give estimated tensions generated by this model that are comparable to those observed experimentally for vertebrate striated muscle.

Adenosine Triphosphatases↗
PubMedDate not supplied

Current treatment and prognosis of Wilms' tumor.

Thanks to the nationally and internationally organized efforts refinements in the therapy of Wilms' tumor have allowed restructuring and reduction of therapeutic strategies. A decrease in tumor relapse and long term sequelae are the immediate goals which will no doubt be the result of tailoring chemotherapy and radiation therapy exposure together with improved surgical techniques and outstanding supportive care.

Child, Preschool↗
PubMedDate not supplied

Retinoblastoma: a review.

Retinoblastoma is the most common primary ocular malignancy in childhood, usually occurring below the age of five. Recent advances in molecular biology have enabled understanding of retinoblastoma tumorigenesis as well as detecting carriers of the mutant retinoblastoma allele. It is possible now to predict prenatally whether a child carries the retinoblastoma genome. This has enabled early detection of retinoblastoma and improved outcome. Also these children are at risk for mesenchymal tumors in early adult life necessitating life long vigilance. Great strides have been made in the management of retinoblastoma. Introduction of a new pathological staging system and addition of combination chemotherapy for extraocular disease has led to more than 80% long term disease free survivors in this group of patients, who earlier had a very poor outcome. For localized intraocular disease, local treatment seems to be all that is necessary. Newer radiation techniques have helped preserve useful vision and reduced radiation related side effects.

Eye Neoplasms↗
PubMedDate not supplied

Treatment of superior vena cava syndrome with recombinant tissue plasminogen activator in a sickle cell patient undergoing bone marrow transplantation.

Superior vena cava (SVC) syndrome is a well-recognized clinical entity seen with mediastinal malignancies and intraluminal venous thrombosis. The role of recombinant tissue plasminogen activator (rt-PA) in the resolution of SVC syndrome caused by thrombosis in the bone marrow transplant settings has not been described. The authors report a case of SVC syndrome with good clinical response in a 16-year-old female with sickle cell disease undergoing an allogeneic bone marrow transplant (BMT) from her HLA identical sibling. Shortly after her transplant, she was found to have significant facial edema and swelling above the neck. Concomitantly, her renal function deteriorated with progressive elevation of serum urea nitrogen and creatinine levels, requiring the use of continuous veno-venous hemofiltration. An upper extremity venogram showed complete SVC obstruction (type III) with apparent inferior reflux into the azygos system. rt-PA was started at a dose of (0.5 mg/kg/day) for 2 days. There was a dramatic resolution of her symptoms, including significant improvement in renal function with increase in urine output. A repeat venogram showed free flow from the distal tip of the central line consistent with a patent superior vena cava. There was no evidence of any bleeding manifestations with rt-PA. This report highlights the usefulness of rt-PA as a treatment modality for SVC syndrome in the BMT settings.

Adolescent↗
PubMedDate not supplied

Detection of a feline X-linked antigen in somatic cell hybrids. Single-cell analysis using monoclonal antibodies.

We tested the premise that monoclonal antibodies to either intracellular or membrane antigens can greatly facilitate the construction of linkage maps of mammals whose chromosomes can be introduced into rodent cells. Monoclonal antibodies against antigenic determinants of cat lymphocytes and fibroblasts were used to analyze feline antigen expression in cat-mouse somatic cell hybrid populations selected to contain the X-linked feline HPRT locus. The frequency of antigen expression as measured by fixed cell immunofluorescence (IF) assays, varied greatly within hybrid populations for all but the antigen designated as VP382. Its frequent presence in hybrid cells led to the prediction, confirmed by 8-azaguanine selection experiments, that its expression was controlled by a gene, or genes, on the feline X chromosome. The antigens identified by the rest of the antibodies segregated independently of each other in cat-mouse somatic cell hybrids and their expression appeared to be controlled by autosomal genes of the cat.

Animals↗
PubMedDate not supplied

The efficacy of ticarcillin-clavulanate and gentamicin as empiric treatment for febrile neutropenic pediatric patients with cancer.

The therapeutic efficacy of ticarcillin-clavulanate and gentamicin was assessed in 56 pediatric cancer patients with 95 febrile neutropenic episodes. The mean temperature of these children on admission was 102 degrees F (range 101 degrees to 106 degrees F), with a median absolute neutrophil count of 60. The median hospital stay was 7 days. All of the patients had one of two types of permanent central lines (Port-A-Cath, N = 75; Hickman, N = 20). Of 20 episodes of bacteremia, 17 had microbial isolates that were gram-positive bacteria and 8 of these episodes required the addition of vancomycin. Clinical cure was achieved in 84 of the 95 febrile episodes (88%) with the use of ticarcillin-clavulanate and gentamicin. There were no fatalities, nor were there any major toxicities. We conclude that the combination of ticarcillin-clavulanate and gentamicin is an effective initial empirical therapy for febrile neutropenic children with cancer. Gram-positive pathogens are the usual cause of breakthrough bacteremia in this clinical setting of central line usage, and associated morbidity and mortality from these organisms are low.

Adolescent↗
PubMedDate not supplied

Primary malignant fibrous histiocytoma of the lung in a child: a case report and review of literature.

Malignant fibrous histiocytoma (MFH), an aggressive high-grade soft tissue sarcoma, usually occurs in the elderly during the fifth to seventh decade of life. It commonly arises in the retroperitoneum, extremities, and head and neck region. Primary pulmonary MFH is extremely rare and is frequently fatal. We present the youngest known case, a 9-year-old boy with a primary left lung grade II inflammatory MFH, stage II. He underwent a left upper lobectomy for tumor resection. After completing radiation therapy, he was started on vincristine, actinomycin D, and cyclophosphamide alternating with vincristine, doxorubicin, and cyclophosphamide every 3 weeks. After five such cycles, he had a histologically proven local recurrence. He then received chemotherapy consisting of ifosfamide (2 g/m2) and etoposide (VP-16) (100 mg/m2) given daily for 3 days every 3 weeks. The patient attained complete remission (CR) after five such cycles and completed treatment without any major complications. He received a total of 16 courses and is continuing in CR 36 months off treatment. Ifosfamide and etoposide (VP-16), known for their usefulness in treatment of adult soft tissue sarcomas, can be used as salvage chemotherapy for patients with MFH who fail the front-line conventional chemotherapy.

Antineoplastic Combined Chemotherapy Protocols↗