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Results for “functional analysis”

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PubMed1985

[Morphological, ultrastructural, cytochemical and functional analysis of neutrophils deficient in myeloperoxidase].

Eighteen patients with established hereditary myeloperoxidase deficiency underwent morphological, ultrastructural, cytochemical and functional analysis in order to correlate the lack of peroxidase from phagocytes with other leucocyte activities. Cytochemical and ultrastructural findings only confirmed the peroxidase defect in neutrophil and monocyte population, whereas normal peroxidase activity was detected in eosinophil granulocytes ("Alius-Grignaschi anomaly"). Morphological analysis, as determined by both ligh and electron microscopy, showed in two patients with total MPO-deficiency a large number of neutrophils (50-60%) with nuclear abnormalities very similar to Pelger-Huet's heterozygous form (two lobed neutrophils having a typical pince-nez appearance and a nuclear chromatin coarser than that of normal PMNL). Other 2 cases displayed a 50-60% five-lobed neutrophils, as occur in congenital nuclear hypersegmentation of PMNL. These findings suggest that Alius-Grignaschi anomaly and Pelger-Huet syndrome can be found associated in the same individuals, since both these abnormalities have a genetic origin. Finally, since an impaired bactericidal and fungicidal activity was observed, no patients displayed particular susceptibility to persistent or severe infections, thus confirming the presence of MPO-independent enzymatic systems.

Blood Bactericidal Activity↗

PubMed1995

Isolation of a functional homolog of the cell cycle-specific NIMA protein kinase of Aspergillus nidulans and functional analysis of conserved residues.

To investigate the degree of conservation of the cell cycle-specific NIMA protein kinase of Aspergillus nidulans, and to help direct its functional analysis, we cloned a homolog (designated nim-1) from Neurospora crassa. Over the catalytic domain NIM-1 is 75% identical to NIMA, but overall the identity drops to 52%. nim-1 was able to functionally complement nimA5 in A. nidulans. Mutational analysis of potential activating phosphorylation sites found in NIMA, NIM-1, and related protein kinases was performed on NIMA. Mutation of threonine 199 (conserved in all NIMA-related kinases) inhibited NIMA beta-casein kinase activity and abolished its in vivo function. This site conforms to a minimal consensus phosphorylation site for NIMA (FXXT) and is analogous to the autophosphorylation site of cyclic-AMP-dependent protein kinases. However, mutation of a unique cysteine residue found only in the catalytic site of NIMA and NIM-1 had no effect on NIMA kinase activity or function. Three temperature-sensitive alleles of nimA that cause arrest in G2 were sequenced and shown to generate three different amino acid substitutions. None of the mutations prevented accumulation of NIMA protein during G2 arrest, but all prevented the p34cdc2/cyclin B-dependent phosphorylation of NIMA normally seen during mitotic initiation even though p34cdc2/cyclin B H1 kinase activity was fully activated.

Amino Acid Sequence↗

PubMed1983

Functional analysis of a herpes simplex virus type 1 promoter: identification of far-upstream regulatory sequences.

We have performed a functional analysis of DNA sequences upstream from the gene for IE mRNA3 of herpes simplex virus type 1. Nucleotide sequences involved in initiation and positive regulation of transcription have been defined by construction of specific deletions in vitro. Transcription was assayed in vivo by microinjection into Xenopus oocytes, or by introduction of plasmid DNA into tissue culture cells and measurement of transient expression. Three functional promoter elements have been defined: i) Sequences between -16 and -37 which are not essential for transcription but are required for accurate initiation. ii) Proximal promoter sequences which are sufficient for transcription initiation in the absence of upstream sequences. iii) Far-upstream promoter sequences (more than 108bp upstream) which increase transcription in oocytes, and contain positive regulatory sequences (-174 to -331) which respond strongly to a factor in the virus inoculum.

Animals↗

PubMed1989

Structure-function analysis of tissue-type plasminogen activator by linker-insertion, point and deletion mutagenesis.

We undertook a structure--function analysis of human tissue plasminogen activator (tPA) using linker-scanning and deletion mutagenesis. Synthetic oligonucleotide linkers were introduced into the tPA cDNA at pre-existing restriction enzyme sites. This generated a series of tPA variants which contained small primary sequence alterations consisting of point mutations, deletions or insertions. The majority of the linker-insertion variants demonstrate a significant reduction in amidolytic and fibrinolytic activity in comparison to wild-type tPA. The exceptions are the variants with linker-inserts placed at the BglII(115) and StyI(277) sites of the tPA cDNA (4SLEG5 and 57LEA58 respectively), which encode insertions at the boundaries of the finger domain. The variants with linker-inserts in the light chain (protease domain) of tPA are the lowest in enzymatic activity. Particularly sensitive to mutation are highly conserved amino acids. Heavy chain deletion variants were constructed from point mutants at the domain boundaries of tPA. Deletion of the kringle domains lowers the fibrinolytic activity to a greater extent than deletion of the finger or growth factor domains. We conclude that alterations in any domain of the tPA molecule, and particularly in the highly conserved residues within these domains, can affect fibrinolytic activity.

Amino Acid Sequence↗

PubMed1990

Functional analysis of ARGRI and ARGRIII regulatory proteins involved in the regulation of arginine metabolism in Saccharomyces cerevisiae.

We present here a functional analysis of ARGRI and ARGRIII regulatory proteins which are involved together with ARGRII in specific regulation of arginine anabolic and catabolic pathways. Unlike ARGRII, ARGRI and ARGRIII have no transcriptional activation capacity. The first 60 amino acids of ARGRI (out of 177) are dispensable for its activity. The functional domain of the protein is located in the region of homology with MCM1 and SRF proteins. ARGRIII contains in its C-terminal portion a stretch of 17 aspartate residues which are indispensable for arginine regulation. Gene disruption of the ARGRIII gene impairs the growth of the mutant on rich medium, showing that ARGRIII has a pleiotropic role in the cell.

Arginase↗

PubMedDate not supplied

The reliability of muscle function analysis using different methods of stimulation.

BACKGROUND: The purpose of our study was to determine the reliability of nonvolitional muscle function analysis (MFA) by determining the day-to-day and within-day reliability of conventional electrical stimulation and a newer, magneto-electrical stimulation method, using standard laboratory methodology. METHODS: Ten healthy, human immunodeficiency virus-negative adult men volunteered as subjects. MFA consisted of measuring the maximal relaxation rate, for magneto-electrical stimulation at 1 Hz and conventional electrical stimulation at 20 Hz, and force-frequency ratios using conventional electrical stimulation at 10 Hz:20 Hz and 10 Hz:50 Hz. Within-day and day-to-day reliability were determined by calculating the coefficient of variation (CV) for all subjects. RESULTS: Maximal relaxation rate using magneto-electrical stimulation had a significantly lower CV compared with the other nonvolitional MFA methods (p = .002). CONCLUSIONS: Maximal relaxation rate using magneto-electrical stimulation was more reliable and technically easier than the other muscle function parameters examined. However, the day-to-day CV of muscle function parameters is larger than traditional nutrition assessment techniques. Development within the field should strive to improve testing techniques so that the reliability of MFA will allow definition of a range of normal values against which an individual's value can be compared. Until this is available, the precision and reliability of MFA restrict its use to research and population studies.

Adult↗

PubMed1997

Functional analysis and treatment of elopement.

Elopement is a dangerous behavior because children who run away may encounter life-threatening situations (e.g., traffic). We conducted functional analyses of the elopement of 3 children who had been diagnosed with developmental disabilities. The results identified a maintaining reinforcer for the elopement of 1 child, but the data were difficult to interpret for 2 of the children. Subsequent reinforcer assessments were used to help to clarify the reinforcers for elopement for these 2 children. Results of the functional analyses and reinforcer assessments then were used to develop successful treatments to reduce elopement. The findings are discussed in terms of (a) the application of functional analysis methodology to elopement, (b) the use of reinforcer assessments to identify potential reinforcers when standard functional analyses are undifferentiated, and (c) the utility of assessment-based treatments for elopement.

Behavior Therapy↗

PubMed1989

Late regrowth of pituitary adenomas after irradiation and/or surgery. Hazard function analysis.

A retrospective analysis was performed on all patients with pituitary adenomas treated at the Radiation Oncology Center, Mallinckrodt Institute of Radiology, St. Louis, Missouri. Of 210 patients treated from April 1954 through December 1982, 70 were treated with radiotherapy alone (RT), 121 received immediate postoperative RT (2 to 6 weeks), and 19 received RT following surgical failure. The mean follow-up time from the date of diagnosis for those patients alive at the time of last follow-up was 13.0 years (range, 3.0 to 30.0 years). Actuarial progression-free survival was analyzed up to 30 years. The 10-, 20-, and 30-year progression-free survival was 80.5%, 73.5%, and 73.5% for those patients treated with irradiation alone and 92.8%, 71.2%, and 44.0% for those treated with immediate postoperative irradiation. The median time to first failure from initial diagnosis by original treatment was 3.8 years for surgery alone, 4.2 years for RT only, and 10.2 years for surgery plus postoperative RT. Analysis for risk of recurrence per 5-year interval was performed using a hazard function analysis. The risk of recurrence after radiotherapy alone was greatest during the first 5-year interval after treatment and decreased to zero by 20 years. However, the risk of recurrence after primary surgery and postoperative radiotherapy revealed an increasing risk for recurrence up to 30 years after treatment. The concept of "cure" for pituitary adenomas requires extended follow-up.

Actuarial Analysis↗

PubMed1995

Functional analysis and treatment of eye poking.

In four studies we analyzed the eye poking of a youth with profound disabilities. In Study 1, a functional analysis showed that eye poking occurred during the no-attention condition, but not during demand, attention or recreation conditions. The analysis did not identify socially mediated variables involved in the maintenance of eye poking; rather, eye poking may have been maintained by consequences produced directly by the response. In Study 2 we had the student wear goggles to prevent potential reinforcement from finger-eye contact. The results of Study 2 indicated that eye-poking attempts were reduced when the student wore goggles. We then tested in Study 3 the effects of two alternative topographies of stimulation. Study 3 demonstrated that eye poking was reduced when a video game was provided as a competing source of visual stimulation, and that music was less effective in reducing eye poking. In Study 4, a contingency analysis using the video game was conducted in an attempt to (a) reduce the frequency of eye poking and (b) study whether the video game functioned as a reinforcer. The results of Study 4 demonstrated substantive reductions in the frequency of eye poking, and suggested that the video game served as a reinforcer.

Acoustic Stimulation↗

PubMed1995

Sex determination from the pubis by discriminant function analysis.

A total of 122 adult human pubes (66 males and 56 females) are used in this study of a discriminant function analysis for determining sex from four pubic measurements: the angle formed by the middle line of the superior ramus and inferior ramus of pubis (in degrees, X1), subpubic angle (in degrees, X2), the minimum distance from the symphyseal surface to the obturator (in millimeters, X3), and the minimum thickness of the ischiopubic ramus (in millimeters, X4). The method introduced by Fisher is used. Using the formula Y = 0.270 mean1-0.985mean2-0.761mean3 + 1.806mean4,F = 200 F = 200 (F > F0.01(4,117), P < 0.01), section point -32.47, an accuracy of 100% could be achieved for 230 pubes (130 males, 100 females).

Discriminant Analysis↗

PubMed1991

Functional analysis of cis-elements, auxin response and early developmental profiles of the mannopine synthase bidirectional promoter.

The dual MAS1'-2' promoter regulating two divergently transcribed mannopine synthase genes has been widely employed in plant expression vectors. As part of an effort towards its rational design as a genetic engineering tool, we have undertaken a functional analysis of the promoter by deletion mutagenesis and by the use of hybrid promoter constructs. Our results indicate that the central region of the intergenic promoter is composed of at least four domains. Three of these contain complementary sequences, which can potentially hybridize to form alternative palindromic structures. These three domains can function cooperatively, and in an orientation-independent manner, in imparting a sevenfold higher expression level at the 2' end relative to the corresponding 1'. The remaining domain is characterized by tracts of repeated A/T-rich elements, and appears to confer the weak activity at the MAS1' promoter end. However, even though this A/T-rich DNA segment is functional, our deletion analysis provided strong evidence that it is completely dispensable for wild-type promoter activity. In addition, the relative distances between these enhancer domains and the 1'-2' TATA-proximal regions can have a pronounced influence on the level of expression in both directions. In young tobacco seedlings, the two promoter ends are expressed in similar, if not identical, tissues in the aerial parts of the plants, but major differences can be observed in roots. Transient expression assays using hybrid promoter constructs showed that cis-elements that can respond to auxin induction signals are redundant in nature, in that they are dispersed throughout the promoter and showed no obvious consensus sequence.

2,4-Dichlorophenoxyacetic Acid↗

PubMed1999

Genetic and functional analysis of genes required for the post-modification of the polyketide antibiotic TA of Myxococcus xanthus.

The antibiotic TA of Myxococcus xanthus is a complex macrocyclic polyketide, produced through successive condensations of acetate by a type I PKS (polyketide synthase) mechanism. The genes encoding TA biosynthesis are clustered on a 36 kb DNA fragment, which has been cloned and analysed. The chemical structure of TA and the mechanism by which it is synthesized indicate the need for several post-modification steps, which are introduced into the carbon chain of the polyketide to form the final bioactive molecule. These include the addition of several carbon atoms originating from acetate carbonyl, three C-methylations, O-methylation and a specific hydroxylation. This paper reports the analysis of five genes which are involved in the post-modification of TA. Their functional analysis, by specific gene disruption, suggests that they may be essential for the production of the active antibiotic. The characteristics and organization of the genes suggest that they may be involved in the addition of the carbon atoms which arise from acetate.

Amino Acid Sequence↗

PubMed1979

[Comparative clinical study of 3 technics of functional analysis of occlusion].

The object of our research is to compare clinically and objectively three articulators: -- the Dentatus, semiadjustable articulator which employs dynamico-static records -- the T.M.J., fully adjustable articulator which employs dynamico-cinematic stereographic endobuccal records -- the Denar, fully adjustable articulator which employs dynamico-cinematic pantographic extrabuccal records. We expressly avoided repeating the mechanical and mathematical analysis of the possibilities and limitations of the articulator and copying the previous researches which always imply quasi-perfection in the behaviour of the patient, in the manipulations of the dental surgeon and in the physical qualities of the articulator and materials used. Our comparative research claims to respect all the variables which occur in the carrying out of an actual case and which are inherent in the patient, the dental surgeon, the articulator and the materials used. In carrying out our research we followed two essential conditions: -- We decided to follow, first of all, a strictly clinical plan using successively the three articulators in the analysis of the occlusal function (carried out twice) for each of the six patients and comparing the results obtained for each articulator and for each patient. -- We decided, next, that this comparative research should be strictly objective. To this end, we did not set out to form an opinion, on the basis of clinical impressions, favourable or unfavourable to the different characteristics of the three articulators. We limited ourselves, on the contrary, to measuring, superposing and making a comparative analysis of the results obtained with the three articulators for the same analysis of the occlusal function.

Dental Arch↗

PubMed1987

Structure-function analysis of fos protein: a single amino acid change activates the immortalizing potential of v-fos.

We have undertaken a detailed structure-function analysis of v-fos protein, taking the ability to induce transformation and immortalization as criteria of biological activity. Our results demonstrate that the evolutionarily conserved center region of fos, comprising ca. 28% of the protein, is indispensable for its function. A single amino acid change (Glu 138----Val 138) in this region activates the immortalizing potential of v-fos without affecting its transforming capacity. The presence of additional either N- or C-terminal amino acids, however, is required for efficient expression of a stable protein, and significantly increases its biological activity. In contrast, sequences in the C-terminal half (between positions 228 and 267) strongly downmodulate the transforming activity of v-fos protein without decreasing its immortalizing potential.

Amino Acids↗

PubMed1989

[Use of bacterial DNA-methylases for structuro-functional analysis of the eukaryotic genome].

Bacterial DNA-methylases with known recognition sites (RS) were used as probes for structural-and-functional analysis of eukaryotic genome. Adenine and cytosine DNA-methylases recognizing 4 to 6-member unique and degenerative nucleotide sequences having a symmetrical and asymmetrical structure were used for probing. The use of a set of methylases enabled the selection of a probe that was the most sensitive for the given pathology. Thus, severe hypothyrosis was found to be associated with changes in the acceptor capacity of liver DNA in the heterologous++ methylation reaction as could be evidenced from testing by two probes, CCCC and GAATGC. In the cells of chicken liver hepatoma MC29, the acceptor capacity of DNA during GGA methylation appeared to be altered in the greatest degree. DNA-methylases with degenerative SR are weakly specific probes for the study of structural changes (methylation) of the animal genome.

Animals↗

PubMedDate not supplied

Functional analysis of Drosophila developmental genes instrumental in tumor suppression.

Of the 28 presently known Drosophila tumor suppressor genes we present the status of the functional analysis of the following three genes: (a) lethal (3) malignant brain tumor [1(3)mbt], which by homology belongs to the Pc-G gene family and may be involved in the stable silencing of specific developmental genes by changing the chromatin structure, and thus establishing and maintaining the differentiated state; (b) lethal (3) malignant blood neoplasm-1 [1(3)mbn-1], for whose function only vague predictions can be made; 4) benign (2) gonial cell neoplasm [b(2)gcn], which may function as a splice factor. Each Drosophila tumor suppressor gene transforms in the homozygously mutated state either one or two specific cell-types in a single step, and is thus the primary cause for tumorigenesis. For one of the genes a putative human homologue has been found.

Animals↗

PubMed1996

Sex determination by discriminant function analysis of lateral radiographic cephalometry.

The present work is an attempt to develop a new method to determine sex from the skull with lateral radiographic cephalometry and discriminant function analysis. The superciliary ridges, frontal sinuses, external occipital protuberance, and mastoid processes were adopted as objects of lateral radiographic cephalometric measurements. With discriminant functions created from 18 established cephalometric variables, a total of 100 cases were classified into two sexual groups with 100% accuracy in a random sample of Taiwanese adults. Therefore, we may obtain a much greater reliability of sex determination from skulls according to this newly developed technique.

Adult↗

PubMed1989

Structure-function analysis of protein active sites with anti-idiotypic antibody.

Antigen and internal image-bearing anti-idiotypic antibody, owing to potential differences in size and chemical nature, need not necessarily demonstrate identical binding specificities. Such differences, termed "dissociability," may be exploited in structure-function analysis of receptor-ligand interaction to identify functionally important amino acid residues, define receptor class, or distinguish receptor conformation. In this sense, ligand and the anti-idiotypes they elicit constitute alternative and complementary probes of protein active sites.

Amino Acid Sequence↗