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Biomedical subjects

C Farrell

Publications and source records attributed to C Farrell.

At least 55 records · Page 3Linked to original sources
PubMed1987

Simplified technique for placement of implantable vascular devices.

A simplified technique for insertion of an implantable vascular device is described. Use of a percutaneous technique with adherence to the steps described with reference to the site of the venipuncture, use of sterile lubricant while introducing the sheathed tapered dilator and Silastic catheter, creation of the subcutaneous pocket after adequate catheter placement and routine use of fluoroscopy helped to avoid technical intraoperative complications, as well as reduce postoperative morbidity.

Catheters, Indwelling↗
PubMed1986

Female marrow donors increase the risk of acute graft-versus-host disease: effect of donor age and parity and analysis of cell subpopulations in the donor marrow inoculum.

We evaluated 27 factors for their influence on acute graft-versus-host disease (GVHD) in 40 recipients of HLA-identical sibling marrow transplants. These factors included the doses of mononuclear cell subpopulations present in the donor marrow inoculum quantitated using a panel of monoclonal antibodies. Female donors were associated with increased severity of acute GVHD, and the older the female donor the greater this effect. Increasing donor parity was also associated with an increased risk of acute GVHD. The number of T cells, T cells subsets, natural killer cells and monocytes infused did not influence the incidence or severity of acute GVHD in this study, and we could not explain the influence of female donors and of female donor age on acute GVHD by the cellular content of their marrow inocula. We postulate that non-HLA histocompatibility antigen disparity is a more important determinant for acute GVHD than the number of infused donor T cells, especially when female donors are used. The association between acute GVHD and increasing parity suggests that some female marrow donors have been pre-sensitized to their respective recipients by preceding pregnancies.

Acute Disease↗
PubMed1985

Neoplasms arising in Paget's disease of bone: a study of 82 cases.

Eighty-two cases of neoplasms arising in Paget's disease of bone from the Mid-America Bone Tumor Registry, accessioned between 1958 and 1983, were reviewed. There were 77 osteosarcomas, 3 fibrosarcomas, 1 chondrosarcoma, and 1 giant cell tumor. The male/female ratio was 2:1. The age distribution was 18%, 29%, 36%, and 17% for the groups less than 51 years, 51-60 years, 61-70 years, and greater than 70 years, respectively. The femur was involved by tumor in 22%; the humerus in 21%; the pelvis in 21%; the calvarium in 12%; the tibia in 10%; and other bones in 15% of the cases. There were 48% survivors after 1 year; 17% after two; and 5% after three and five years; two additional patients with tumor lived for more than seven and 11 years. Radiographs available for simultaneous study in 43 cases revealed predominant tumor patterns that were mixed in 69%, osteoblastic in 21%, and osteolytic in 10%. Other radiographic data and the clinical and histopathologic data are in agreement with five earlier major studies. While the prognosis of neoplasms arising in Paget's disease generally is not good, a small fraction of long-term survivors after aggressive therapy makes this complication a challenge for timely radiographic diagnosis and histopathologic confirmation.

Adult↗
PubMed1984

Physical properties of the E. coli 4.5S RNA: first results suggest a hairpin helix of unusual thermal stability.

Hyperchromicity measurements and quasi-elastic laser light scattering (QELS) have been used to assess the solution structure of the metabolically stable E. coli 4.5S RNA. Results from thermal denaturation measurements revealed the 4.5S species to be markedly more stable than most other RNAs characterized thus far. Optical Tm's range from 79 degrees to 88 degrees with transitions approximately 25 degrees C wide. The Tm values show little dependence on ionic strength, but stability is enhanced considerably by Mg+2. In the QELS experiments the diffusion coefficient does not decrease until T greater than 70 degrees C. Neither the diffusive melting nor the diffusion coefficient at infinite dilution (D0(20,w)) show dependencies on ionic strength but both are influenced by Mg+2. The diffusion behavior is in agreement with that predicted for a rigid cylindrical molecule 125 to 160 A long and 37 to 26 A in diameter. Taken together these results are consistent with the more stable hypothetical secondary structures that can be formed, in which 70-75% of the 114 bases are paired to form a single extended hairpin helix.

Base Sequence↗
PubMed1984

The interaction of unregulated actin and myosin in avian muscular dystrophy.

The presence of an altered form of the heavy chain component of myosin subfragment-1 (S-1) in avian dystrophic pectoral muscle was confirmed by Triton-urea-acetic acid polyacrylamide gel electrophoresis. The potential functional significance of this altered form of S-1 was evaluated by measuring the ATPase activity of the unregulated acto-S-1 complex using all possible pairwise combinations of actin and S-1 from normal (N) and dystrophic (D) muscle. (NN, DD, ND, DN, where the first letter designates the actin and the second letter the S-1). With conventionally purified actin and S-1, NN not equal to DD not equal to ND not equal to DN, implying both N actin not equal to D actin and N S-1 not equal to D S-1 functionally. An alternate purification scheme for actin resulted in preparations from normal and dystrophic muscles of actin Mg-polymers with the same rheology (viscosity vs shear rate) and critical concentration for polymerization. When these actins were combined with more highly purified preparations of S-1, the adenosine triphosphatase (ATPase) activity of the acto-S-1 complex did not vary with changes in the pairwise composition and responded similarly to variation of the actin or adenosine triphosphate (ATP) concentration. In experiments with actin activation of intact myosin, no differences were observed between myosin from normal vs dystrophic muscle. The different isozymes of myosin present in normal and dystrophic chicken pectoral muscles are functionally equivalent as ATPases in their interactions with unregulated actin.

Actins↗
PubMed1981

Case report 158.

Explore the source record for details and available documents.

Chondrosarcoma↗
PubMed1980

Soluble immune complexes in cerebrospinal fluid of patients with multiple sclerosis and other neurological diseases.

The occurrence of soluble immune complexes (IC) in the cerebrospinal fluid (CSF) of 14 multiple sclerosis (MS) patients, four acute polyradiculoneuritis patients, 30 patients with other neurological diseases (OND) and 30 patients with disc prolapse (DP) was examined by a solid phase C1q-protein A binding assay (C1q-PABA) and a complement consumption test. IC-positive reactions were observed only in the C1q-PABA. The binding indices determined by the C1q-PABA differed significantly (P < 0.01) when the MS or the OND patient groups were compared to the DP group. No significant (P < 0.1) difference was observed between the indices in the MS and OND groups. Binding indices in C1q-PABA showed no correlation either to IgG concentration, total protein concentration or cell counts in CSF of MS patients. Three of the four polyradiculoneuritis patients were strongly IC-positive while the fourth patient was negative. Filtration and PEG-precipitation data indicated that a major part of the IgG-containing IC in CSF detected by C1q-PABA was of macromolecular nature.

Adolescent↗
PubMed1980

Determining growth rates of focal lesions of bone from radiographs.

Rate of growth divides focal lesions of bone into two classes which are largely mutually exclusive. Not all focal lesions require biopsy, and grading is especially helpful in deciding which should be biopsied and which may be safely followed. The statistical proof and logic of grading as an expression of growth rate are presented with a set of rules establishing each of the five grades in the presence of bone destruction. The radiologic signs necessary to establish rates are described and illustrated.

Bone Neoplasms↗
PubMed1980

Estimating rate of growth in bone lesions: observer performance and error.

In an experimental study of reader experience in identifying the variables essential to grading bone neoplasms, reader error is measured against book grade, a human consensus of the presence or absence of key variables. The average accuracy for classifying focal lesions into slow or fast categories is 83.4% for 890 readings as compared with average diagnostic accuracy of 53.7%. Analyses of human error have provided insight into how to improve the grading algorithm without significant loss of its ability to separate lesions into meaningful categories.

Bone Neoplasms↗