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S M Wilson

Publications and source records attributed to S M Wilson.

At least 145 records · Page 8Linked to original sources
PubMed1984

A new assay for factors that regulate the synthesis of granulocyte differentiation proteins in vitro.

Morphological and molecular aspects of granulocyte differentiation can be studied concomitantly using liquid cultures of immature granulocytes in conjunction with a newly developed high-performance liquid chromatographic (HPLC) assay for differentiation proteins. Immature granulocytes, isolated from guinea pig bone marrow by Ficoll density centrifugation, were placed in liquid cultures and incubated for periods up to 1 week. In the presence of 10% dialyzed, normal guinea pig serum, these cells were almost all converted to mature granulocytes, whereas at serum concentrations below 1% mostly macrophages were formed. Cell multiplication does not appear to be necessary for granulocyte maturation in this culture system. The data also show that morphological maturation in vitro is accompanied by the formation of all the major membrane and secondary granule differentiation proteins detected by the HPLC assay in extracts of mature granulocytes formed in vivo. The techniques described here should facilitate the isolation and purification of the factors in normal serum that control the induction of synthesis of these differentiation markers.

Animals↗
PubMed1984

Characteristics of a cationic amino acid transport system in the basolateral membrane of the cat salivary epithelium.

The specificity and kinetics of L-lysine influx across the basolateral surface of the cat salivary epithelium have been investigated in the perfused cat submandibular gland using a high-resolution, paired-tracer dilution technique. L-lysine influx was measured at several different perfusate concentrations (0.05-2.5 mM) and was found to be saturable. A Michaelis-Menten analysis based on a single entry site gave a Km of 0.49 +/- 0.08 mM and a Vmax of 231 +/- 20 nmol/min X g. The uptake of L-lysine was highly stereospecific and markedly inhibited by L-arginine (0.25-2.5 mM). The inhibitor constant (Ki) was 0.23 mM, suggesting that the carrier had a greater affinity for L-arginine than L-lysine. When the inhibitory effects of L-histidine (0.5-10 mM) were examined the Ki, estimated at 10 mM, was 4.6 mM. Nine other neutral amino acids (L-alanine, L-serine, L-cysteine, glycine, L-proline, L-homoserine, L-leucine, L-phenylalanine and L-glutamine), and an acidic amino acid (L-aspartate) were also tested at 10 mM and, although several caused inhibition, the Ki was always at least 20 times higher than the measured Km for L-lysine. It is concluded the carrier is highly specific for the L-form of the basic amino acids. The sodium dependence of L-lysine influx was investigated over a range of L-lysine concentrations (0.05-1 mM), and total removal of sodium from the perfusate had no effect on L-lysine influx. In the presence of sodium, L-homoserine, an amino acid not normally present in animal tissues, inhibited L-lysine influx (Ki = 13 mM). This inhibition was not observed in the absence of sodium, and contrasts with the observation that the inhibitory action of L-histidine was sodium independent. The present data suggest that a specific cationic amino acid transport system is operative in the basolateral membrane of the cat salivary epithelium. The properties of this system appear to be similar to the system y+ which has been described in several other cell types.

Amino Acids↗
PubMed1980

Reaction of antithrombin with proteases. Evidence for a specific reaction with papain.

Experiments were performed to determine if the sulfhydryl protease, papain (EC 3.4.22.2), reacts with the plasma protease inhibitor antithrombin (antithrombin III, heparin cofactor) on a specific manner analogous to the reaction of thrombin (EC 3.4.21.5) and other serine proteases with this inhibitor. The esterolytic activity of papain is blocked by the addition of antithrombin, but not by antithrombin-thrombin complex or by protein substrates such as bovine serum albumin. Likewise, in the presence of papain, antithrombin was unable to displace the active site dye proflavine from thrombin, or to inhibit thrombin-catalysed hydrolysis of an anilide substrate. The reaction of antithrombin and papain was not accelerated by low concentrations of heparin. Approximately stoichiometric amounts of heparin completely inhibited the reaction of papain with antithrombin. The mutual inhibition indicates that plasma antithrombin does react with papain but the reaction differs from the interaction with coagulation factors, particularly in the heparin effect.

Antithrombin III↗
PubMed1980

Electron microscope study of the kinetics of the fiber-to-crystal transition of sickle cell hemoglobin.

The intermediates and the rate-limiting step in the crystallization of deoxygenated sickle hemoglobin have been determined by a kinetic study with the use of electron microscopy. In slowly stirred solutions of deoxygenated hemoglobin S [Pumphrey, J. & Steinhardt, J. (1977) J. Mol. Biol. 112, 359--375], the sequential appearance of fibers have a diameter of approximately equal to 210 A, bundles of aligned fibers in well-ordered arrays, "thick" fibers of approximately equal to 470 A diameter, and microcrystals is observed. Only the fibers having a diameter of approximately equal to 210 A and bundles of aligned fibers are assigned as kinetically important intermediates of the fiber-to-crystal transition. Addition of microscopic seed crystals obtained from slowly stirred solutions of deoxyhemoglobin S to a solution composed of only fibers and hemoglobin monomers results in more rapid crystallization than in control solutions. Addition of seed crystals after the formation of bindles of aligned fibers does not alter the overall kinetics of crystallization. The results demonstrate that alignment of fibers is the rate-limiting step in the crystallization process and results in formation of nucleation sites for crystal growth.

Anemia, Sickle Cell↗
PubMed1980

Effects of carbaryl on variable interval response rates in rats.

Sic male rats were trained on a variable interval 5 min schedule of reinforcement. Each rat, serving as its own control, was given itraperitoneal (IP) and intramuscular (IM) injections of 1, 3, 5, and 10 mg/kg l-naphthyl N-methylcarbamate (carbaryl). There were significant decreases in response rate following 3, 5, and 10 mg/kg IP injections and 5 and 10 mg/kg IM injections of carbaryl.

Animals↗
PubMed1979

Fractionation of granule proteins of granulocytes by copper chelate chromatography.

The tendency of lactoferrin to associate with other proteins at low salt concentrations defeated attempts to fractionate the acetate-extracted granule proteins of guinea pig granulocytes by ion-exchange chromatography. This problem was overcome by using copper-chelate chromatography at high salt concentrations to separate lactoferrin from the other granule proteins. Lysozyme and a 'cationic protein' were purified to apparent homogeneity in the same operation. The chromatographic profile of proteins extracted from purified secondary granules differed from that of proteins extracted from total granules chiefly in the absence of a substantial 'cationic protein' peak.

Animals↗
PubMed1979

Activation of lung connective tissue cells in vitro.

Guinea pig lung fibroblasts "activated" in vitro by exposure to connective tissue-activating peptides I and III, and guinea pig tissue extracts showed enhanced glycolysis and accelerated glycosaminoglycan synthesis. Formation of hyaluronic acid, and to a lesser extent, chondroitin 4/6-sulfate was stimulated by these agents.

Animals↗
PubMed1979

Effect of inflammatory serum on 14C-glucosamine incorporation into bone marrow granulocytes in vitro.

As a preliminary approach to developing a biochemical assay for detecting humoral regulators of granulocyte maturation in the normal and inflammatory states, studies were carried out on the effects of normal and inflammatory sera on the incorporation of 14C-glucosamine into the glycoproteins of bone marrow granulocytes in vitro. We observed that, relative to normal serum, inflammatory serum had a marked stimulatory effect on 14C-glucosamine incorporation into these glycoproteins. This property of inflammatory serum reached a maximum at about 8 h after the initiation of inflammation in vivo and preceded the maximum increase in the mitotic activity of granulocyte precursors in the marrow by 18 h. It was also found that normal serum contains both dialyzable and heat-sensitive nondialyzable factors that inhibit 14C-glucosamine incorporation into bone marrow granulocytes in vitro. Data are presented which indicate that the stimulatory effect of inflammatory serum is most likely due to a nondialyzable factor which is capable of blocking the effect of the inhibitors present in normal serum.

Animals↗
PubMed1978

Polyamine synthesis in bone marrow granulocytes: effect of cell maturity and early changes following an inflammatory stimulus.

Enriched fractions of mature and immature neutrophil granulocytes, isolated from guinea pig bone marrow, were assayed for ornithine decarboxylase activity and polyamine content. The results show that immature granulocytes contain at least ten times more ornithine decarboxylase activity and two times more spermidine than mature granulocytes. The incorporation of 14C-ornithine into putrescine and spermidine of intact immature granulocytes was three to four times and ten times, respectively, that of mature granulocyte preparations. Six hours after an inflammatory stimulus, transient increases of 14-fold and 3-fold in the activities of ornithine decarboxylase and S-adenosyl-L-methionine decarboxylase, respectively, were observed in immature bone marrow granulocytes. At this time the incorporation of 14C-ornithine into putrescine and spermidine in bone marrow granulocytes from stimulated animals was 14 times that of cells from controls. A maximum increase in DNA synthesis in these cells during the inflammatory response occurred 6 hr after the maximum increase in the polyamine synthetic activity. Together these data suggest that polyamine synthesis in the granulocyte compartment of the bone marrow is associated chiefly with immature proliferating cells and that increased polyamine synthesis precedes increased granulocyte proliferation in the bone marrow following an inflammatory stimulus.

Adenosylmethionine Decarboxylase↗
PubMed1977

Hemoglobin Tarrant: alpha126(H9) Asp leads to Asn. A new hemoglobin variant in the alpha1beta1 contact region showing high oxygen affinity and reduced cooperativity.

Hemoglobin (Hb) Tarrant was detected by its electrophoretic mobility on cellulose acetate (pH 8.4) and citrate agar (pH 6.2). On cellulose acetate it moved as a band between hemoglobins F and S, and on citrate agar as a band at hemoglobin S. The test for solubility in 2 M phosphate buffer with Na2S2O4 was negative. The new variant has a substitution of asparagine for aspartic acid in position 126 of the alpha-chain, one of the sites involved in the alpha1beta1 contact. Furthermore, in deoxyhemoglobin aspartic acid 126 of each alpha chain also forms a non-covalent electrostatic salt bridge with arginine 141 of the corresponding alpha chain (Perutz, M. F. and Ten Eyck, L. F. (1972) Cold Spring Harbor Symp. Quant. Biol. 36, 295-310 and Perutz, M. F. (1970) Nature 228, 726-739). As a consequence of this substitution in hemoglobin Tarrant, the deoxy conformation or T state is destabilized because these two bridges cannot be formed. This condition is reflected in high oxygen affinity and low cooperativity.

Amino Acid Sequence↗
PubMed1976

Surgical treatment of hepatic metastases from colorectal cancers.

Follow-up data covering periods of two to 23 years have been collected on 60 patients who had resection of hepatic metastases for colorectal cancer. Multiple lesions were removed from 20 patients, and solitary lesions were excised from the other 40 patients. Only one patient died during hospital convalescence. No patient who had multiple lesions excised lived for five years. In contrast, 15 of the 36 patients eligible for five-year survival study who had resection of apparent solitary lesions lived for five years or more, and eight patients were alive without evidence of recurrence ten years or more after operation. These surprisingly favorable results of surgical treatment were analyzed in relation to results in patients who had biopsy specimens taken of lesions of comparable size and number, but no removal at the time of colonic resection. No patient in this control group lived for five years. Aggressive surgical treatment of apparent solitary hepatic metastatic lesions from colorectal cancer seems to be justified by the survival rate of surgically treated patients.

Adult↗
PubMed1976

Intraoperative fiberoptic colonoscopy--"the difficult polypectomy".

An alternative to transcolonic polypectomy, transabdominally directed, transanal colonoscopic polypectomy, for patients who require polyp removal but in whose cases standard colonoscopic approach has failed is presented. The early results are excellent, and the method also can be applied to other patients who have colonic polyps who undergo procedures such as hysterectomy and cholecystectomy.

Aged↗
PubMed1976

Adenocarcinoma arising in a sigmoid diverticulum: report of a case.

A case of adenocarcinoma arising in a sigmoid diverticulum is presented. A patient who had colonic diverticulosis was found to have one diverticular lumen distended by tumor mass. Microscopically, this was seen to be adenocarcinoma arising from the diverticular mucosa. Apparently, this is the first reported case of adenocarcinoma arising in an intact diverticulum of the colon.

Adenocarcinoma↗
PubMed1976

The curative treatment of carcinoma of the sigmoid, rectosigmoid, and rectum.

This retrospective series comprises 902 patients who underwent curative resection of the sigmoid colon, rectosigmoid, and upper rectum at the Mayo Clinic during the years 1959 to 1969. Lesions were divided according to the location from the dentate line, with 346 patients having had a lesion located more than 20 cm from the dentate line; in the remaining 556 patients, the lesion was between 6 and 20 cm distant. A thorough analysis was undertaken comparing these two groups of patients on the basis of operative mortality and morbidity, including anastomotic complications, 5- and 10-year survival, and incidence of local recurrence. Overall operative mortality was 1.9%, with an 8.1% incidence of anastomotic complications. The overall 5-year survival rate was 72% and the 10-year survival rate was 55%. The incidence of anastomotic recurrence for anastomosis performed with the use of extraperitoneal rectum was 5.8%; recurrence at the suture line developed in 2.9% of patients who underwent anastomosis to serosa-covered bowel. In addition to the above data, information will be presented which demonstrates the effect of the patient's height and weight on the surgeon's ability to perform a low-anterior anastomosis. Finally, the incidence of anastomotic complications and of local recurrence were analyzed according to the intestinal preparation employed, the use of parenteral antibiotics , and the method of drainage used near the anastomosis.

Adenocarcinoma↗
PubMed1976

Carcinoma of the anus.

Carcinoma of the anus represents about 2% of cancers of the large bowel. From 1950 to 1970, 20 patients were treated for this condition. Included were 113 patients with squamous cell carcinoma (31 perianal), 64 with basalid squamous carcinoma, 8 with Paget's disease of the anus, 7 with melanoma, 6 with basal cell carcinoma, and 6 with adenocarcinoma. Combined abdomino-perineal resection was the treatment of choice except for perianal lesions; for these, local excision was used most frequently. Inguinal node dissection was used infrequently, and it is not possible to draw meaningful conclusions from the data. Overall survival rates for patients having anal squamous cell carcinoma are similar except when lymphatic invasion is present; then basaloid lesions have a significantly better prognosis. For rare anal carcinomas, histopathologic findings dictate the end results-- the better the findings and more satisfactory the results.

Adenocarcinoma↗
PubMed1976

Lack of gonadotropic activity in the rabbit blastocyst prior to implantation.

Recent reports of an LH-like hormone in the rabbit preimplantation blastocyst and of elevated serum progesterone levels in the presence of unimplanted blastocysts prompted us to characterized further the biological activity of the presumed gonadotropin. Progesterone was measured by a highly specific radioimmunoassay in sera obtained from pregnant and pseudopregnant rabbits after mating (day 0) to fertile or vasectomized males. On days 3, 4, 5, and 6, which represent the preimplantation period, mean progesterone concentrations (ng/ml +/- SE) were 4.3 +/- 0.7, 5.1 +/- 0.5, 6.8 +/- 1.1, and 9.0 +/- 1.9 in 5 pseudopregnant rabbits and 4.1 +/- 0.4, 6.7 +/- 0.6, 5.9 +/- 0.9, and 7.0 +/- 0.8 in 7 pregnant rabbits. In a separate experiment, serum progesterone concentrations in 6 pseudopregnant and 8 pregnant rabbits were 10.1 +/- 0.7 ng/ml and 13.7 +/- 1.1 (P less than 0.02), respectively on days 11-12. Thus, serum progesterone concentrations were not different in pregnant and pseudopregnant rabbits before the time of implantation (day 7), but were higher in pregnant rabbits after implantation. Blastocysts obtained on day 6 and incubated with a cell suspension of immature rat ovaries failed to stimulate the accumulation of progesterone in medium, in contrast to hCG, which was active even in the presence of blastocysts. Day-6 blastocysts also failed to stimulate the accumulation of testosterone from decapsulated rat testes and of progesterone from rabbit ovarian tissues in vitro. A gonadotropic effect of the conceptus can be observed in the rabbit within 4 to 5 days after implantation. However, we find no evidence for the existence of an LH-like hormone in the preimplantation blastocyst which stimulates the rabbit ovary to secrete progesterone.

Animals↗