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Biomedical subjects

S D Patterson

Publications and source records attributed to S D Patterson.

At least 109 records · Page 6Linked to original sources
PubMed1986

The equine protease inhibitory system (Pi): abnormal expressions of PiF, PiL, and PiS1.

Three cases of abnormal expression of the equine protease inhibitory alleles, Pi F, L, and S1, were observed following the examination of 30,000 plasma samples by one-dimensional acid (pH 4.6) polyacrylamide gel electrophoresis. Characterization of the abnormal proteins in terms of isoelectric point, molecular mass, inhibitory spectra, and sialic acid content was performed using one- and two-dimensional electrophoretic techniques. The Pi F and S1 abnormalities were postulated to be the result of amino acid substitutions causing alterations in the processing of the carbohydrate side chains. No explanation could be offered for the Pi L abnormality other than a charge shift mutation. Abnormal types, F*, L*, and S1* behaved as alleles but the distribution of L* in offspring from one stallion (present in only 6 of 83 offspring) differed significantly from expectation.

Alleles↗
PubMed1983

Intravascular, bronchiolar, and alveolar tumor of the lung (IVBAT). An analysis of twenty cases of a peculiar sclerosing endothelial tumor.

Twenty cases of an unusual tumor of the lung are described. This tumor usually presents with multiple small, slowly growing pulmonary nodules. Many cases are detected incidentally. Eighty percent are women, and 50% are less than 40 years of age. Survival with tumor can be quite long. However, one half the patients have died, usually of progressive pulmonary insufficiency. This is a peculiar sclerosing tumor of endothelial cell origin.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMed1982

The pathology of Yersinia enterocolitica ileocolitis.

The terminal ileum and proximal colon were resected in two children presenting with fever and right lower quadrant abdominal pain. The pathological findings were characteristic; elongated ulcerations with underlying lymphoid hyperplasia involved the distal ileum and smaller punctate aphthoid ulcers involved the distal ileum and colon. Transmural inflammation was seen in both cases and resulted in thickened, erythematous distal ileum mistaken at surgery for Crohn's disease. Yersinia enterocolitica was recovered from operative cultures of both the specimens. One of the two patients had a 1:1280 serological titer for Yersinia enterocolitica 1 week after surgery. The pathologic findings of Yersinia enterocolitica ileocolitis are distinctive and easily differentiated from Crohn's disease and other pathologic processes in this region. Operative diagnosis can be difficult but if the possibility of Yersinia infection is considered, the correct diagnosis can usually be made without unnecessary surgical resection.

Child↗
PubMed1975

Phosphatidate phosphohydrolase and palmitoyl-coenzyme A hydrolase in cardiac subcellular fractions of hyperthyroid rabbits and cardiomyopathic hamsters.

Activities of phosphatidate phosphohydrolase and palmitoyl-CoA hydrolase were determined in cardiac subcellular fractions prepared from rabbits which has received tri-iodothyronine and from hamsters with hereditary cardiomyopathy (strain BIO 14.6). 1. Both mitochondrial and microsomal fractions of hyperthyroid rabbit hearts produced 4-5 times as much diacylglycerol 3-phosphate from glycerol 3-phosphate and palmitate as did those of euthyroid hearts. 2. Phosphatidate phosphohydrolase, measured with phosphatidate emulsion, was activated by 1mm-Mg(2+) in all but the mitochondrial fraction of euthyroid rabbit hearts. The activation was more pronounced in subcellular fractions isolated from hyperthyroid hearts, so that the measured activities were significantly increased above those of the controls. The highest activity was found in the microsomal and lysosomal fractions. 3. In the absence of Mg(2+) during incubation, the difference in phosphohydrolase activities between eu- and hyper-thyroid states was not significant. 4. The phosphohydrolase of subcellular fractions of control hamsters did not respond to addition of 0.5-8.0mm-Mg(2+). The enzyme from cardiomyopathic hearts was slightly inhibited by this bivalent cation and therefore significant increases in activity were observed only in the absence of Mg(2+) from the assay system. 5. The rate of reaction by soluble phosphatidate phosphohydrolase was similar regardless of the nature of the substrate. Both when microsomal-bound phosphatidate was used as the substrate and when phosphatidate suspension was used, the activity of soluble enzyme was lower than that of the microsomal and lysosomal enzymes measured with phosphatidate suspension; this was especially so when the assay was carried out in the absence of Mg(2+). Neither tri-iodothyronine nor cardiomyopathy influenced the soluble phosphohydrolase activity in the two species. 6. Neither tri-iodothyronine nor cardiomyopathy significantly changed palmitoyl-CoA hydrolase activities in subcellular fractions. 7. Microsomal diacylglycerol acyltransferase and myocardial triacylglycerol content were also unchanged in the hyperthyroid state.

Acid Phosphatase↗
PubMed1975

Phosphatidate phosphohydrolase and palmitoyl coenzyme A hydrolase in cardiac subcellular fractions.

The characteristics of the two enzymes related to fatty acid esterifaction were studied in order to provide fundamental information leading to further understanding of the control of myocardial glyceride formation. Palmitoyl-CoA hydrolase and phosphatidate phosphohydrolase are both distributed unevenly among heart subcellular fractions. The activity of the latter enzyme in subcellular fractions changes independently in response to Mg2+ addition and in response to thyroid hormone treatment of animals.

Animals↗
PubMedDate not supplied

Comparison of in-gel and on-membrane digestion methods at low to sub-pmol level for subsequent peptide and fragment-ion mass analysis using matrix-assisted laser-desorption/ionization mass spectrometry.

The success of the mass spectrometric-based approaches for the identification of gel-separated proteins relies upon recovery of peptides, without high levels of ionization-suppressing contaminants, in solvents compatible with the mass spectrometer being employed. We sought to determine whether in-gel or on-membrane digestion provided a significant advantage when low to sub-pmol quantities of gel-separated proteins were analyzed by matrix-assisted laser-desorption/ionization mass spectrometry (MALDI-MS) with respect to the number and size of released peptides. Serial dilutions of five standard proteins of M(r) 17,000 to 97,000 (from 16 pmol to 125 fmol) were electrophoresed and subjected to in-gel digestion (using a microcolumn clean-up protocol, Courchesne, P.L. and Patterson, S. D., BioTechniques, 1997, in press) or on-membrane digestion following blotting to the PVDF-based membranes, Immobilon-P and Immobilon-CD. Peptide maps were able to be obtained for all proteins at the detection limit of each method (Immobilon-P and Immobilon-CD, 0.5 pmol; and in-gel, 125 fmol), and searches of Swiss-Prot or a non-redundant database (> 193000 entries) successfully identified all of the proteins, except beta-casein. Fragment-ion spectra using a curved-field reflector MALDI-MS were obtained from more than one peptide per protein at loads down to 250 fmol (except beta-casein). Using the uninterpreted data, a search of the nonredundant database and a six-way translation of GenBank dbEST (> 2,208,000 entries total) was able to identify myoglobin, carbonic anhydrase II, and phosphorylase b.

Acrylic Resins↗
PubMedDate not supplied

Effect of screw placement on fixation in the humeral head.

The objectives of this study were (1) to determine the most advantageous screw locations within the humeral head when plate and screw fixation is to be used and (2) to determine the effect of positioning the screw tip abutting the subchondral bone. Ten paired humeral heads were harvested with a monoplanar cut through the anatomic neck. Through use of a standardized template, 7 holes were drilled and tapped in each specimen for insertion of 6.5-mm fully threaded cancellous screws perpendicular to the plane of the cut. Paired specimens were randomized into 2 groups, one with the screw purchase in central cancellous bone and the other with the screw purchase up to the subchondral bone. Each screw was pulled out axially at a displacement rate of 10 mm/min through use of a servohydraulic testing machine. The length of thread purchase, position within the head, and screw pullout load to failure were recorded. The normalized pullout force to failure was calculated by dividing absolute pullout force to failure by length of screw purchase. Data were analyzed by means of a 2-way repeated measures analysis of variance and post hoc Student-Newman-Keuls test. The central position had a significantly higher absolute pullout force to failure than all other sites (P < .05). By virtue of the humeral head shape, the central position also had a significantly greater length of screw purchase than all other positions (P < .05). The central position had a significantly higher relative pullout force to failure than all other positions (P < .05). Subchondral bone abutment positioning improved both the absolute and the relative pullout forces to failure (P < .05). When screws and plates are used in open reduction and internal fixation of a proximal humerus fracture, a major mode of failure is loss of fixation within the humeral head. On the basis of this study, optimal screw purchase with respect to bone fixation can be achieved by including screws located in the center of the humeral head in the subchondral abutment position. To minimize screw fixation failure, the anterosuperior position should be avoided. The pattern of distribution of the relative pullout force as measured in this study is consistent with previous observational studies of patterns of trabecular density within the humeral head.

Aged↗
PubMedDate not supplied

Carcinoid tumor of the larynx: the role of conservative therapy.

Carcinoid tumors of the larynx are an extremely rare condition, universally malignant, and unresponsive to radiation and chemotherapy. Just over 20 cases have been reported in the literature to date. Treatment is adequate surgical excision. The number of these tumors reported should increase due to the use of electron microscopy and immunohistologic techniques in making the diagnosis. This paper illustrates the role of conservative laryngeal surgery, when appropriate, as an effective form of therapy. The basic pathologic diagnostic criteria are illustrated.

Biopsy↗
PubMedDate not supplied

Distal biceps brachii tendon repair. An in vitro biomechanical study of tendon reattachment.

Clinical reports suggest that suture anchors can simplify repair of distal biceps tendon avulsions. In this study, fixation strengths of Mitek and Statak suture anchors were compared with strength of reattachment using transosseous suture tunnels in eight cadaveric radii. Cyclic loading and load-to-failure testing were performed: No specimen failed during testing to 50 N for 3600 cycles: however, four of the Mitek anchors and one of the Statak anchors protruded out of the medullary canal. The mean load to failure of the Mitek suture anchor complexes was 220 +/- 54 N, that of the Statak suture anchor complexes was 187 +/- 64 N, and that of the transosseous sutures was 307 +/- 142 N. There was no significant difference in the failure load or mechanism of failure between the Statak and Mitek anchors. Transosseous sutures failed at significantly greater loads on static testing than the suture anchors. Cyclic loading results suggest that the bony fixation achieved using these three techniques should be sufficient to allow immediate passive mobilization of the elbow after surgery. Protrusion of the suture anchors out of the tuberosity during cyclic loading is a concern because of potential development of a gap at the repair site and interference with forearm rotation.

Arm Injuries↗
PubMedDate not supplied

Nasal blastoma: a light and electron microscopic study.

The first light and electron microscopic study of a nasal blastoma is reported. Analogous to a pulmonary blastoma, the tumor is composed of well-differentiated squamous and glandular epithelial elements surrounded by a spindle cell stroma. The spindle stromal cell is a myofibroblast. Eighteen months after complete surgical removal of the tumor and radiation therapy, the patient is clinically free of disease.

Adult↗
PubMedDate not supplied

Granular cell tumor of the thyroid gland in a girl receiving high-dose estrogen therapy.

We describe the first case of a granular cell tumor of the thyroid. The tumor appeared while a girl was receiving high-dose estrogen therapy for tall stature. The tumor, however, did not contain estrogen or progesterone receptors. Although granular cell tumors occur twice as commonly in women as in men, the results of this case study do not provide evidence that tumor growth is mediated by direct estrogen or progesterone stimulation.

Child↗