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S D Patterson

Publications and source records attributed to S D Patterson.

At least 91 records · Page 5Linked to original sources
PubMed1993

Evaluation of storage phosphor imaging for quantitative analysis of 2-D gels using the Quest II system.

The advent of storage phosphor technology has been of considerable benefit to the imaging of gel-separated radiolabeled proteins due to the rapid and quantitative nature of the data acquisition process. Previously, times over one month were required to obtain fluorographs of the same gel to yield data of sufficient dynamic range for quantitative analysis of high-resolution two-dimensional (2-D) gels. As we are in the process of building a human 2-D gel protein database, and therefore have a high throughput of 2-D gels both to image and quantitate using the Quest II software, we undertook an evaluation of a storage phosphor imager, including an evaluation of signal fade. The results of this evaluation demonstrate the feasibility of using such a system, and we describe the procedures that allow us to use this technique for quantitative analysis of many complex 2-D gel patterns. These procedures include a useful batch printing program that allows printing of many images in a non-interactive mode. Examples will be presented of how autoradiography, using storage phosphor plates and the Quest II system, have enabled us to begin building a human 2-D gel protein database including posttranslational modification information, without the previous time constraints associated with such a project.

Autoradiography↗
PubMed1992

Cutaneous T-cell lymphoma. Evaluation of pretreatment skin biopsy specimens by a panel of pathologists.

BACKGROUND AND DESIGN: Cutaneous T-cell lymphoma (CTCL) frequently presents a difficult diagnostic challenge for the clinician and pathologist. To assess the diagnostic validity of conventional histopathologic findings in CTCL, pretreatment skin biopsy specimens were scored prospectively and independently by a panel of five to seven dermatopathologists and pathologists. Scores were compared with disease outcome. Repeatability of these scores was examined among observers and for the same observer. The study population consisted of 165 subjects, initially referred for suspected mycosis fungoides or Sézary syndrome. Ninety-two patients determined to have CTCL have been followed up for 6.3 +/- 3.5 years (mean +/- SD) and are categorized according to disease outcome: 22 are in complete remission, 35 are in partial remission, three have progressive lymphoma, 15 died of disease, 13 died of other causes, and four were unavailable for follow-up. Seventy-three patients determined not to have CTCL have been followed up for 5.3 +/- 3.2 years without subsequent clinicopathologic evidence of CTCL. These longitudinal data allowed comparisons of the clinical course with the original histologic interpretations. RESULTS: Data showed that the histologic scores rendered by the pathology panel did not correlate with stage of disease and were not an accurate predictor of clinical outcome, because the histologic ratings did not discriminate between patients who eventually had complete remission and those with either progressive lymphoma or who have died of disease. The results also substantiate the low inherent reliability of histopathologic findings in CTCL. Large differences existed among pathologists in scoring the study populations and repeated reading of selected cases by the same panel member resulted in a change of diagnosis 15% of the time. Among the histologic features evaluated, only the presence of mitoses in the infiltrating cells showed a trend toward an unfavorable outcome. CONCLUSION: Pathologic diagnosis in the CTCL disease spectrum should be interpreted with caution and then only in conjunction with the clinical evaluation. As expected, the use of an average value from a panel of readers added a component of stability to the histologic interpretation.

Biopsy↗
PubMed1992

High-yield recovery of electroblotted proteins and cleavage fragments from a cationic polyvinylidene fluoride-based membrane.

In this report we describe the use of a novel, experimental, polyvinylidene fluoride-based membrane with a cationic surface for the isolation by electroblotting of small amounts of proteins separated by gel electrophoresis for further characterization by protein fragmentation for internal sequence analysis. The membrane is characterized by a surface that mediates primarily ionic protein/membrane interactions and that allows the recovery of adsorbed proteins at high yields under relatively mild conditions. In electroblotting experiments, the novel membrane has a binding capacity that is at least equivalent to that of standard polyvinylidene fluoride membranes and is compatible with both chemical and enzymatic fragmentation of blotted proteins in situ. Intact electroblotted proteins, or fragments thereof, were eluted at high yields. Further structural analysis is demonstrated using reverse-phase high-performance liquid chromatography or gel electrophoresis to separate cleavage fragments for either pulsed-liquid- or solid-phase automated sequence analysis.

Cations↗
PubMed1991

The equine major plasma serpin multigene family: partial characterization including sequence of the reactive-site regions.

The equine Pi system, which is highly polymorphic and was considered to be controlled by a single locus, has been shown to be controlled by four loci (named Spi 1-4). This system is the equine equivalent of the major human plasma serpin (serine protease inhibitor), human alpha 1 PI. Twenty-two haplotypes of the equine Pi system have been characterized by two-dimensional electrophoresis, resulting in the assignment of pI, Mr, and bovine trypsin and chymotrypsin inhibition characteristics to 109 proteins. These proteins have been analyzed further to determine their relatedness to each other as well as to human alpha 1 PI using immunochemical, structural, and functional criteria. The amino acid sequences of the N termini and reactive-site regions have been determined on proteins from each of the four equine Spi loci. This allowed the designation of the proteins from the Spi 1 locus as being METserpins and the functional equivalents of human alpha 1 PI. The Spi 4 proteins are ARGserpins, and by alignment the Spi 2 proteins are ILEserpins, the first so far described. The P1 residue for the Spi 3 proteins was unable to be determined. The limited peptide and immunopeptide mapping revealed that proteins from all four loci were closely related, but within the four there were two pairs (Spi 1 and 2 and Spi 3 and 4) which were more related. All were probably derived from the same gene that gave rise to human alpha 1 PI.

Amino Acid Sequence↗
PubMed1991

Mammalian alpha 1-antitrypsins: comparative biochemistry and genetics of the major plasma serpin.

1. Human alpha 1-antitrypsin (alpha 1 AT) has been extensively characterized and reviewed. It is the archetypal member of the superfamily of serine proteinase inhibitors, the serpins. As human alpha 1-antitrypsin exhibits a relatively high concentration in plasma and is usually the highest concentration serpin, it can be referred to as the major plasma serpin. 2. alpha 1-Antitrypsin from species other than man has been characterized for two major reasons: (1) for use in a model animal system to assist with the study of the human alpha 1 AT deficiency disease; and (2) to find polymorphism for use in gene mapping and linkage studies or for parentage analysis. 3. The diverse range of reasons for studying alpha 1AT has yielded a vast array of literature that is often not well cross-referenced. 4. The characteristic features of alpha 1AT in all species examined to date will be presented with a view to examining which features are important structurally and functionally from an evolutionary perspective. 5. In mouse, horse, rabbit and guinea pig, multigene families which appear to have arisen from alpha 1AT have been found. The functional and evolutionary implications of these paralogous genes will also be discussed.

Amino Acid Sequence↗
PubMed1991

Donkey and horse alpha 1 B-glycoprotein: partial characterization and new alleles.

1. The donkey postalbumin protein has been shown to be the equivalent of human alpha 1 B-glycoprotein by protein immunoblotting and N-terminal amino acid sequence. 2. The horse A1B system (already identified as the homologue of human alpha 1 B-glycoprotein) and the donkey alpha 1 B-glycoprotein were characterized further for terminal sialic acid content, isoelectric point, amino acid composition and affinity for the dye-ligand, Cibacron Blue F3GA (known to bind human alpha 1 B-glycoprotein). 3. Two new alleles in the horse A1B system were found, bringing the total number of alleles to five. No polymorphism was found in the donkey alpha 1 B system. 4. As expected the first 20 N-terminal residues of the donkey and horse proteins are highly conserved with only two differences being found. 5. The polymorphism of the horse alpha 1 B-glycoproteins may be due in part to differing numbers of terminal sialic acid residues and the higher electrophoretic mobility of the donkey alpha 1 B-glycoprotein may be due in part to increased sialylation. 6. The horse and donkey alpha 1 B-glycoproteins exhibited differences in affinity for the dye-ligand, Cibacron Blue F3GA, with the donkey alpha 1 B-glycoprotein not being bound.

Alleles↗
PubMed1991

The tammar wallaby major plasma serpin: partial characterization including the sequence of the reactive site region.

1. The putative equivalent of the human major plasma serpin (alpha 1-proteinase inhibitor or alpha 1-antitrypsin) in the tammar wallaby (Macropus eugenii) has been further characterized by structural (peptide and immunopeptide mapping and sequence studies) and functional analyses revealing close homology of the wallaby proteins to human alpha 1-proteinase inhibitor. 2. A sixth allele, Pi J, was detected and its products characterized in terms of pI, Mr, inhibitory spectra and terminal sialic acid content. 3. A recently-developed electrophoretic in situ oxidation/binding method was adapted to provide protein suitable for sequence analysis of the N-terminus and reactive site region including assignment of the P1 and P'1 residues. 4. All sequence analyses were performed on proteins or peptides (approximately Mr 3500) blotted onto polybrene treated GF/C or polyvinylidene difluoride membrane respectively. 5. The P5 to P'4 residues of the reactive centre are identical with those of the human inhibitor thereby allowing the wallaby inhibitor also to be classified as a METserpin. 6. The P1 methionine is presumably responsible for the oxidation sensitivity observed in the electrophoretic in situ functional assay for the wallaby inhibitor. 7. The plasma concentration of the wallaby inhibitor is similar to that reported for human alpha 1-proteinase inhibitor.

Alleles↗
PubMed1990

Equus przewalskii plasma protease inhibitor (Pi) system.

A detailed biochemical characterization of four of the five previously described alleles of the plasma protease inhibitor (Pi) system of Equus przewalskii was performed using both one- and two-dimensional electrophoretic techniques. The proteins have been characterized in terms of isoelectric point, relative molecular mass, inhibitory activity to bovine trypsin and chymotrypsin, immunochemical cross-reactivity, terminal sialic acid content and enzyme:inhibitor complex formation and the oxidation sensitivity of this interaction. Using these functional criteria, only three loci (Spi 1, 2 and 3) were found to control the plasma Pi proteins of the E. przewalskii haplotypes. In contrast a fourth locus, Spi 4, was found in some E. caballus haplotypes. The significance of these results with respect to the complexity of the protein pattern exhibited by the equine Pi multigene family is discussed.

Alleles↗
PubMed1990

The carbohydrate side chains of the major plasma serpins of horse and wallaby: analyses of enzymatic and chemically treated (including 'Smith degradation') protein blots by lectin binding.

The carbohydrate side chains of the major plasma serpins of the horse and wallaby have been characterized by lectin analyses of protein blots from two-dimensional gels using the major human plasma serpin, alpha 1-protease inhibitor, as a control. Eight lectins were used in the characterization in conjunction with enzymatic deglycosylation of complex and high mannose side chains, chemical desialylation and defucosylation, and one round of 'Smith degradation', all being performed on the nitrocellulose blots. Assuming a standard complex side chain structure, the results of the 21 lectin/treatment combinations were interpreted as indicating that the equine proteins consist of partially sialylated biantennary side chains except for the most acidic proteins which have triantennary side chains. The wallaby proteins have bi- and triantennary side chains with a bisecting N-acetylglucosamine and fucose residue present.

Animals↗
PubMed1990

Comparison of alcohol, tobacco, and illicit drug use among students and delinquents in the Bahamas.

Surveys of drug use were conducted among 4,767 junior and senior high school students in 1987 and 74 incarcerated delinquents in 1988 in the Bahamas. It was found that the majority of both groups reported having drunk alcohol, and substantial proportions had also smoked tobacco, although over twice as many delinquents as students had smoked. However, use of illicit drugs was far more common among delinquents, at seven times the student rate for marijuana and six times their rate for cocaine. Many social and demographic similarities were found among users in both groups, who were likely to be males who had trouble in school or did not attend school, were not religiously active, and came from families where drugs were used or sold. Over one-third of the delinquents had sold drugs, but almost half (44%) of the delinquents and 25% of the students said they would use or sell marijuana or cocaine if they had it. The results of the studies point to the need for increased drug education in the Bahamas and for efforts involving schools, churches, parents, the media, and Government.

Adolescent↗
PubMed1989

Application of an affinity electrophoretic and in situ oxidation method to the study of the equine protease inhibitory proteins.

An affinity method was developed to investigate the interaction between protease and protease inhibitor by incorporating a protease incubation step into a two-dimensional electrophoretic separation of the plasma protease inhibitory proteins. This involved the application of the isoelectric focusing gel to filter paper saturated in the protease of choice before being placed on the second-dimensional polyacrylamide electrophoresis gel. General protein staining or immunoblotting was used to detect the protein or ligand in the complex. An in situ oxidation method was developed using the reagent chloramine T to investigate the effect of this reagent on the complexing abilities and inhibitory activities of the protease inhibitory proteins. Oxidation was performed either after electrophoresis prior to staining for enzyme inhibition or during two-dimensional electrophoresis prior to the aforementioned protease incubation. The latter allowed the effect of oxidation on complex formation to be examined. Whole plasmas were utilized as the sources of protease inhibitory proteins with the human and mouse being used as models. The equine protease inhibitory system was examined by the two methods and shown to consist of three classes of inhibitory proteins based on their susceptibilities to oxidation and abilities to form complexes with various proteases.

Animals↗
PubMed1989

[Comparison of the abuse of alcohol, tobacco and drugs between students and delinquents in the Bahamas].

Surveys of drug use were conducted among 4,767 junior and senior high school students in 1987 and 74 incarcerated delinquents in 1988 in the Bahamas. It was found that the majority of both groups reported having drunk alcohol, and substantial proportions had also smoked tobacco, although over twice as many delinquents as students had smoked. However, use of illicit drugs was far more common among delinquents, at seven times the student rate for marijuana and six times for cocaine. Many social and demographic similarities were found among users in both groups, who were likely to be males who had trouble in school or did not attend school, were not religiously active, and came from families where drugs were used or sold. Over one-third of the delinquents had sold drugs, but almost half (44%) of the delinquents and 25% of the students said they would use or sell marijuana or cocaine if they had it. The results of the studies point to the need for increased drug education in the Bahamas and for efforts involving schools, churches, parents, the media, and Government.

Adolescent↗
PubMed1988

Subdivision of equine Tf into H1 and H2.

Subdivision of equine TfH into two variants, designated H1 (faster) and H2 (slower), has been accomplished by high voltage, thin layer polyacrylamide gel electrophoresis at pH 7.9. Transferrin H1 and H2 have been shown to be controlled by codominant alleles and gene frequencies of the Tf alleles have been determined in the Australian Thoroughbred, Standardbred. Quarter Horse and Arabian Horse breeds.

Alleles↗
PubMed1988

Acute phase response in the horse: plasma protein changes associated with adjuvant induced inflammation.

The induction of an acute phase response in four horses by adjuvant administration was used to examine the effect on the levels of plasma proteins. Blood parameters (packed cell volume, total plasma protein, red blood cell count, haemoglobin concentration) were monitored to follow the progress of the acute phase response in parallel with the examination of plasma proteins. Plasma protein levels were determined by densitometry from the electrophoretic patterns of three different gel systems. Haptoglobin and alpha 1 B glycoprotein were shown to be positive acute phase reactants whereas albumin was a negative acute phase reactant. Plasma esterase and proteins of the Pi system did not change following the experimental inflammation.

Acute-Phase Reaction↗
PubMed1987

Tammar wallaby plasma protease inhibitory (Pi) proteins.

Electrophoretic examination (isoelectric focusing and polyacrylamide gel electrophoresis) of 157 plasmas from a Kangaroo Island population of tammar wallabies (Macropus eugenii) resulted in the identification of five putative condominant protease inhibitor alleles, F, I, M, P and S, which exhibited microheterogeneity due to variable terminal sialic acid content. The frequencies of the five alleles in this population were 0.041(F), 0.682(I), 0.194(M), 0.073(P) and 0.010(S). The proteins had isoelectric points in the pH range 3.94-4.38, Mr of 60,500 to 66,000 and were identified as protease inhibitors by their abilities to inhibit both trypsin and chymotrypsin. Protein blotting of the denatured proteins demonstrated cross reaction with antiserum to human alpha 1-protease inhibitor.

Alleles↗
PubMed1987

ISO-DALT characterization of 12 'new' equine plasma protease inhibitor (Pi) alleles.

Twelve equine protease inhibitory alleles, PiE, H, J, K, L2, O, P, Q, R, V, X, Z, have been characterized in terms of isoelectric point, molecular mass and inhibitory activity to bovine trypsin and chymotrypsin by ISO-DALT electrophoresis. Protein maps for 20 Pi alleles including those of the eight 'Thoroughbred' alleles (PiF, G, I, L, N, S1, S2, U) have now been determined. Five pairs of alleles, S1/S2, G/K, L/L2, P/R and U/Z, possessed varying numbers of common proteins ranging from one protein in the case of G/K and L/L2 to six in the case of U/Z. Based on these results and studies of the abnormal expressions of PiF, PiL and PiS1, a theory of at least three closely linked loci has been postulated to account for the marked heterogeneity of the equine protease inhibitory system.

Alleles↗
PubMed1987

Frequencies of plasma protease inhibitor alleles in Australian horse breeds and the recognition of two new alleles.

Investigation of the plasma protease inhibitor system (Pi) in the Arabian and quarter horse breeds and re-examination of the standardbred breed resulted in the recognition of two new Pi alleles, designated E and L2. PiE is rare and has been found in only three quarter horses. In contrast, PiL2 is relatively common in the standardbred (0.107) and allowed subdivision of PiL into PiL and PiL2. Splitting of PiL resulted in an exclusion probability (PE) of 0.649 for the standardbred Pi system. Frequencies of the Pi genes have now been determined for four breeds (thoroughbred, standardbred, quarter horse and Arabian) of horses in Australia.

Alleles↗