Adrenoleukodystrophy associated with psychosis.
Explore the source record for details and available documents.
Adrenoleukodystrophy↗
Biomedical subjects
S Tan
Publications and source records attributed to S Tan.
Novel dimerization fold of RAP30/RAP74 in human TFIIF at 1.7 A resolution.
General transcription factor IIF (TFIIF) is required for transcription by RNA polymerase II; it consists minimally of a heterodimer of RNA polymerase-associated proteins RAP30 and RAP74. According to solution and mutagenesis studies, the multiple domains of RAP30 and RAP74 bind PolII, TFIIB, TAF250 and DNA in interactions that are essential for transcription initiation and elongation. The X-ray structure of the RAP30/RAP74 interaction domains at 1.7 A resolution reveals a novel "triple barrel" dimerization fold and suggests with mutant data that interactions with the transcription apparatus are mediated not only by this tripartite beta-barrel, but also via flexible loops and alpha and beta-structures extending from it.
Amino Acid Motifs↗
Crystallization of the yeast MATalpha2/MCM1/DNA ternary complex: general methods and principles for protein/DNA cocrystallization.
We describe our efforts to crystallize binary MCM1/DNA and ternary MATalpha2/MCM1/DNA complexes, including the unsuccessful attempts to crystallize MCM1/DNA complexes and the successful design of DNA crystal packing that resulted in high-resolution crystals of the MATalpha2/MCM1/DNA complex. We detail general procedures useful for preparing protein/DNA cocrystals, including improved methods for producing and purifying DNA-binding proteins and DNA fragments, for purifying protein/DNA complexes, and for controlling pH conditions during crystallization. We also describe the rational design of DNA for protein/DNA cocrystallization attempts, based on our analysis of how straight and bent DNA with single base-pair overhangs can pack end-to-end in a crystal.
Base Pairing↗
Erythema ab igne: an old condition new again.
Explore the source record for details and available documents.
Adult↗
Patients' perception of sound levels in the surgical suite.
STUDY OBJECTIVES: To measure sound levels that our patients are exposed to in the surgical suite and their perception of these sound levels. DESIGN: Sound levels experienced by 100 patients undergoing general anesthesia for elective surgery during three phases: induction and maintenance of anesthesia in the operating room (OR), and recovery from anesthesia in the recovery room, were measured using a Type 4436 Noise Dose Meter. The equivalent continuous sound levels (Leq), maximum sound levels (Lmax), and the sources of sounds were noted. Patients were interviewed 24 hours after anesthesia about their perception of the sound levels they had experienced in the OR and recovery rooms. MEASUREMENTS AND MAIN RESULTS: The Leq during the induction, maintenance, and recovery phases were 70.3 +/- 16.8 dB(A), 66.2 +/- 4.1 dB(A) and 71.8 +/- 6.1 dB(A), respectively. These sound levels are much higher than international recommendations for hospital acute care areas and exceed the thresholds to produce noise-induced cardiovascular and endocrine effects. Sound levels were significantly higher during the induction and recovery phases compared to the maintenance phase. Thirty-two patients found the induction phase noisy and 33 patients found the recovery phase noisy. The sound levels distressed 16 patients and 52 patients would have preferred a quieter environment. There was no difference in the sound levels experienced by those who expressed dissatisfaction with the sound levels and those who did not. Much of the noise, particularly staff conversations, unnecessary alarms, and preparation of equipment, could have been prevented by simple measures. CONCLUSION: Noise prevention in the OR and recovery room needs more attention and should be a routine part of patient care.
Anesthesia↗
The effect of polishing systems on microleakage of tooth coloured restoratives: Part 1. Conventional and resin-modified glass-ionomer cements.
The purpose of this in vitro study was to investigate the effect of polishing systems on the microleakage of conventional and resin-modified glass-ionomer cements. Class V cavities were prepared at the cemento-enamel junction of 80 freshly extracted posterior teeth. The prepared teeth were randomly divided into two groups and restored with conventional or resin-modified glass-ionomer cements. The restored teeth were stored in distilled water at 37 degrees C for 1 week after removal of excess restorative with diamond finishing burs. The restored teeth were then divided into four groups of 10 and finished and polished using the following systems: Two Striper MFS; Sof-Lex XT; Enhance Composite Finishing and Polishing System; Shofu Composite Finishing Kit. The finished restorations were subjected to dye penetration testing. Results showed that the microleakage at dentin margins of conventional glass-ionomer cements and enamel margins of resin-modified glass-ionomer cements are significantly affected by the different polishing systems.
Analysis of Variance↗
Changes in prostaglandin and nitric oxide levels in the hyperdynamic circulation following liver resection.
BACKGROUND AND AIMS: Significant changes in hepatic haemodynamics occur after major hepatectomy, but the pathogenesis of this phenomenon is unclear. This study investigates the serum profile of prostaglandin and nitric oxide in the hepatic and systemic circulation before and after hepatectomy and the temporal relationship of these to changes in the hepatic blood flow. METHODS: Blood samples were collected from the internal jugular, portal and hepatic veins of six Yorkshire pigs (17-25 kg) before, immediately after and 48 h after partial hepatectomy. RESULTS: Serum levels of prostacyclin I2 (PGI2) and prostaglandin E2 (PGE2) from the systemic circulation, the portal circulation and from the hepatic veins were found to differ considerably even before hepatectomy. After the hepatectomy was performed, there was a significant rise in PGI2 levels in the systemic circulation (P=0.027). Hepatic blood flow and cardiac output were measured before hepatectomy, 24 and 48 h after hepatectomy in another six pigs. A significant increase in hepatic blood flow (P=0.029) occurred after the hepatectomy and this was accompanied by a concomitant increase in the cardiac output (P=0.042). The increase in PGI2 concentration in the systemic circulation after hepatectomy appears to accompany the development of hyperdynamic hepatic and systemic circulations. No significant change was found in circulating PGE2 levels in the systemic, portal and hepatic veins at the three collection intervals (i.e. pre, post and 48 h after hepatectomy). The PGE2 levels in the hepatic vein, however, were significantly higher from than in the portal vein (P=0.028). No significant changes were observed in the level of nitric oxide. CONCLUSION: This study demonstrates an increase in the total hepatic blood flow after hepatectomy together with a threefold increase in prostacyclin in the systemic circulation. The liver was identified as the main source of circulatory prostaglandin.
Animals↗
Extremal-point densities of interface fluctuations in a quenched random medium
We give a number of exact, analytical results for the stochastic dynamics of the density of local extrema (minima and maxima) of linear Langevin equations and solid-on-solid lattice growth models driven by spatially quenched random noise. Such models can describe nonequilibrium surface fluctuations in a spatially quenched random medium, diffusion in a random catalytic environment, and polymers in a random medium. In spite of the nonuniversal character for the quantities studied, their behavior against the variation of the microscopic length scale can present generic features, characteristic of the macroscopic observables of the system.
Journal Article↗
Analysis of fission yeast primase defines the checkpoint responses to aberrant S phase initiation.
To investigate the checkpoint response to aberrant initiation, we analyzed the cell cycle checkpoint response induced by mutations of Schizosaccharomyces pombe DNA primase. DNA primase has two subunits, Spp1 and Spp2 (S. pombe primases 1 and 2). Spp1 is the catalytic subunit that synthesizes the RNA primer, which is then extended by DNA polymerase alpha (Polalpha) to synthesize an initiation DNA structure, and this catalytic function of Polalpha is a prerequisite for generating the S-M phase checkpoint. Here we show that Spp2 is required for coupling the function of Spp1 to Polalpha. Thermosensitive mutations of spp2(+) destabilize the Polalpha-primase complex, resulting in an allele-specific S phase checkpoint defect. The mutant exhibiting a more severe checkpoint defect also has a higher extent of Polalpha-primase complex instability and deficiency in the hydroxyurea-induced Cds1-mediated intra-S phase checkpoint response. However, this mutant is able to activate the Cds1 response to S phase arrest induced by temperature. These findings suggest that the Cds1 response to the S-phase arrest signal(s) induced by a initiation mutant is different from that induced by hydroxyurea. Interestingly, a polalphats mutant with a defective S-M phase checkpoint and an spp2 mutant with an intact checkpoint have a similar Polalpha-primase complex stability, and the Cds1 response induced by hydroxyurea or by the mutant arrests at the restrictive temperature. Thus, the Cds1-mediated intra-S phase checkpoint response induced by hydroxyurea can also be distinguished from the S-M phase checkpoint response that requires the initiation DNA synthesis by Polalpha.
Alleles↗
Syncollin is differentially expressed in rat proximal small intestine and regulated by feeding behavior.
Gradients of gene expression are maintained along the proximal-distal axis of the mammalian small intestine despite a continuously regenerating epithelium. To study the molecular mechanisms responsible for this phenomenon, we utilized a subtractive hybridization strategy to isolate genes differentially expressed in the duodenum but not ileum. We isolated and sequenced 15 clones. The clones were fragments of genes encoding lipases, proteases, and an esterase. A novel clone was characterized and subsequently shown to encode syncollin, a secretory granule protein that binds to syntaxin in a calcium-sensitive manner. RT-PCR and S1 nuclease protection assay were used to clarify the 5'-end of syncollin. Syncollin was expressed in the rat pancreas, spleen, duodenum, and colon. In situ hybridization localized syncollin expression in the pancreas to acinar cells and in the duodenum to villus epithelial cells.
Amino Acid Sequence↗
Imprint switching for non-random X-chromosome inactivation during mouse oocyte growth.
In mammals, X-chromosome inactivation occurs in all female cells, leaving only a single active X chromosome. This serves to equalise the dosage of X-linked genes in male and female cells. In the mouse, the paternally derived X chromosome (X(P)) is imprinted and preferentially inactivated in the extraembryonic tissues whereas in the embryonic tissues inactivation is random. To investigate how X(P) is chosen as an inactivated X chromosome in the extraembryonic cells, we have produced experimental embryos by serial nuclear transplantation from non-growing (ng) oocytes and fully grown (fg) oocytes, in which the X chromosomes are marked with (1) an X-linked lacZ reporter gene to assay X-chromosome activity, or (2) the Rb(X.9)6H translocation as a cytogenetic marker for studying replication timing. In the extraembryonic tissues of these ng/fg embryos, the maternal X chromosome (X(M)) derived from the ng oocyte was preferentially inactivated whereas that from the fg oocyte remained active. However, in the embryonic tissues, X inactivation was random. This suggests that (1) a maternal imprint is set on the X(M) during oocyte growth, (2) the maternal imprint serves to render the X(M) resistant to inactivation in the extraembryonic tissues and (3) the X(M) derived from an ng oocyte resembles a normal X(P).
Amnion↗
X-chromosome inactivation in XX androgenetic mouse embryos surviving implantation.
Using genetic and cytogenetic markers, we assessed early development and X-chromosome inactivation (X-inactivation) in XX mouse androgenones produced by pronuclear transfer. Contrary to the current view, XX androgenones are capable of surviving to embryonic day 7.5, achieving basically random X-inactivation in all tissues including those derived from the trophectoderm and primitive endoderm that are characterized by paternal X-activation in fertilized embryos. This finding supports the hypothesis that in fertilized female embryos, the maternal X chromosome remains active until the blastocyst stage because of a rigid imprint that prevents inactivation, whereas the paternal X chromosome is preferentially inactivated in extra-embryonic tissues owing to lack of such imprint. In spite of random X-inactivation in XX androgenones, FISH analyses revealed expression of stable Xist RNA from every X chromosome in XX and XY androgenonetic embryos from the four-cell to morula stage. Although the occurrence of inappropriate X-inactivation was further suggested by the finding that Xist continues ectopic expression in a proportion of cells from XX and XY androgenones at the blastocyst and the early egg cylinder stage, a replication banding study failed to provide positive evidence for inappropriate X-inactivation at E6. 5.
Animals↗
Validation of the fluorescence polarization assay and comparison to other serological assays for the detection of serum antibodies to Brucella abortus in bison.
A number of serological tests were compared for the detection of antibodies to Brucella abortus in bison (Bison bison). The performance of the fluorescence polarization assay (FPA) in both the preliminary evaluation and a subsequent blind validation indicated that this test was the most suitable for serological diagnosis of brucellosis in bison. The sensitivity and specificity in the preliminary evaluation were 92.1% and 99.4%, respectively. The sensitivity and specificity in a subsequent blind study were 96.3% and 97.6%, respectively. In a double blind study conducted on bison vaccinated with B. abortus strain 19, the data suggests that the FPA can differentiate bison infected with B. abortus from bison vaccinated with B. abortus strain 19. Both the indirect immunoassay (IELISA) and the competitive immunoassay (CELISA) performed nearly as well as the FPA. The buffered antigen plate agglutination test (BPAT) and the complement fixation test (CFT) did not perform as well as the FPA, CELISA or the IELISA in both studies. The FPA is a homogeneous assay eliminating the washing steps and reducing incubation to minutes rather than hours saving on time, equipment, materials, reagents and cost. These attributes, together, with its excellent sensitivity and specificity make the FPA an attractive test for the detection of serum antibodies to Brucella abortus in bison.
Agglutination Tests↗
Safety and immunogenicity of lyophilized, live attenuated hepatitis A vaccine in non-human primate model.
OBJECTIVE: To evaluate the safety and immunogenicity of lyophilized, live attenuated hepatitis A vaccine (H2 strain) in rhesus monkeys. METHODS: Nine adult rhesus monkeys were used as experimental animals. The rhesus monkeys without anti-HAV were divided randomly into the aqueous vaccination group (4 rhesus monkeys), the lyophilized vaccination group (3 rhesus monkeys), and the control group (2 rhesus monkeys). Monkeys were inoculated by intramuscular injection, with control monkeys being inoculated with Minimum Essential Medium Eagle (MEM). Following vaccination, the monkeys were observed for the development of diarrhoea and other adverse side-effects, such as changes in appetite, frequency of defaecation and stool consistency for seven days. At the weeks 2, 3, 4, 6, 8, 10 and 12 positnoculation, the peripheral blood was collected from all animals and assayed for anti-HAV and alanine aminotransferase (ALT) and aspartate aminotransferase (AST), at weeks 0, 4 and 8 postinocuation, needle-biopsy specimens were taken at weeks 0, 4, 8 and 12, all monkeys were sacrificed and tissue samples were taken from liver, lung, heart, kidney and brain for pathological examination at week 12. RESULTS: Animals were immunized with a dose of 7.0 logTCID50/ml which is stable after freeze-drying. During the 12-week observation, no animals showed abnormal elevations of liver enzymes (ALT and AST) and no change in appetite or activity. Two monkeys (one in the aqueous group and the other in lyophilized group) showed possible lesions at week 8. The lyophilized vaccine, in addition to eliciting an anti-HAV IgG response similar to aqueous vaccine (P > 0.05), also showed IgM anti-HAV response at week 2 which was not observed with aqueous vaccine. CONCLUSIONS: These results demonstrate that lyophilized, live hepatitis A vaccine is safe and highly immunogenic in primates, supporting its further evaluation in human clinical studies.
Animals↗
[Studies on vaccination schedule of inactivated hepatitis A vaccine].
OBJECTIVE: To evaluate three vaccination schedules of inactivated hepatitis A vaccine in rhesus monkeys (Macaca Mulatta). METHODS: Seventeen rhesus monkeys were divided randomly into four groups. The first group of five monkeys was immunized with vaccination schedule 1 (one immunization at week 0); The second group of five monkeys was immunized with vaccination schedule 2 (first injection at week 0, and booster one at week 4); the third group of five monkeys was immunized with vaccination schedule 3 (first injection at week 0, and booster one at week 24); and the fourth group of two monkeys with MEM as control. Rhesus monkeys were inoculated by intramuscular injections to detect the ALT (alanine aminotransferase), liver pathology and anti-HAV at different time. RESULTS: During the 52-week observation, no abnormal elevation of ALT or liver pathology appeared. The IgG response for vaccination schedule 1 reached the highest level (13 219 mIU/ml), and decreased gradually to 2 056 mIU/ml at week 52. After booster immunization at week 4, the IgG response for vaccination schedule 2 was 13 863 mIU/ml at week 12, and decreased to 6 285 mIU/ml. The highest level of IgG (40 638 mIU/ml) for vaccination schedule 3 appeared at week 28 after booster injection at week 24. Further more, at week 52 the IgG level for vaccination schedule 3 was also the highest among the three vaccination schedules. CONCLUSIONS: The inactivated hepatitis A vaccine is safe and well immunogenic. The vaccination schedule 3 showed the best immune response among the three vaccination schedules.
Adult↗
Characterization of two chloroplast RNA polymerase sigma factors from Zea mays: photoregulation and differential expression.
Two distinct cDNAs encoding putative sigma factors of plastid RNA polymerase were isolated from Zea mays, a C4 plant. The deduced amino acid sequences of both cDNAs possess all four highly conserved domains proposed for recognition of -10 and -35 promoter elements, core complex binding, DNA binding, and melting. These two cDNAs are designated sig1 and sig2. Phylogenetic analysis of available plastid sigma factors indicated that they were probably the descendants of cyanobacterial principal sigma factors. Southern blots probed with sig1 and sig2 revealed that both genes exist in the maize nuclear genome as single-copy genes, but low-stringency hybridization suggested the presence of a multigene family of maize plastid sigma factors. Transcription of sig1 and sig2 is light inducible and tissue specific. Transcripts of sig1 and sig2 were abundant in greening leaf tissues; sig2 (but not sig1) was barely detectable in etiolated leaves and neither was detectable in roots. Immunological studies using a peptide antibody against an epitope in subdomain 2.4 of Sig1 revealed 50-kDa and 60-kDa immunoreactive proteins in maize chloroplasts. Reduced levels of the 60-kDa immunoreactive protein were detected in etioplasts, and no immunoreactive proteins were observed in roots. Collectively, the data suggest that the nuclear genes, sig1 and sig2, may play a role in differential expression of plastid genes during chloroplast biogenesis.
Amino Acid Sequence↗
A phylogenetic assessment of the eukaryotic light-harvesting antenna proteins, with implications for plastid evolution.
The light-harvesting complexes (LHCs) are a superfamily of chlorophyll-binding proteins present in all photosynthetic eukaryotes. The Lhc genes are nuclear-encoded, yet the pigment-protein complexes are localized to the thylakoid membrane and provide a marker to follow the evolutionary paths of plastids with different pigmentation. The LHCs are divided into the chlorophyll a/b-binding proteins of the green algae, euglenoids, and higher plants and the chlorophyll a/c-binding proteins of various algal taxa. This work examines the phylogenetic position of the LHCs from three additional taxa: the rhodophytes, the cryptophytes, and the chlorarachniophytes. Phylogenetic analysis of the LHC sequences provides strong statistical support for the clustering of the rhodophyte and cryptomonad LHC sequences within the chlorophyll a/c-binding protein lineage, which includes the fucoxanthin-chlorophyll proteins (FCP) of the heterokonts and the intrinsic peridinin-chlorophyll proteins (iPCP) of the dinoflagellates. These associations suggest that plastids from the heterokonts, haptophytes, cryptomonads, and the dinoflagellate, Amphidinium, evolved from a red algal-like ancestor. The Chlorarachnion LHC is part of the chlorophyll a/b-binding protein assemblage, consistent with pigmentation, providing further evidence that its plastid evolved from a green algal secondary endosymbiosis. The Chlorarachnion LHC sequences cluster with the green algal LHCs that are predominantly associated with photosystem II (LHCII). This suggests that the green algal endosymbiont that evolved into the Chlorarachnion plastid was acquired following the emergence of distinct LHCI and LHCII complexes.
Amino Acid Sequence↗
A prospective comparison of brain contrast characteristics and lesion detection using single-shot fast spin-echo and fast spin-echo.
MRI is limited by movement artefact, even with current imagers, when examining a restless or claustrophobic patient. We prospectively analysed the images of 92 patients produced by a single-shot fast spin-echo (SSFSE) pulse sequence and compared them with conventional (FSE) and reduced-time fast spin-echo (RT-FSE) techniques, with regard to lesion detection and movement artefact in brain imaging. Images obtained in each case were independently reviewed and scored for overall diagnosis, number of lesions detected, and movement artefact. FSE showed 1217 lesions, RT-FSE 1137, and SSFSE 1044. This discrepancy arose mainly in patients with multiple sclerosis or small-vessel disease, since with SSFSE we were less able to separate small, adjacent low-contrast lesions than with FSE. Arbitrary movement scores were 36, 25 and zero respectively. There were, however, no clinically significant differences in overall diagnosis between the three techniques. SSFSE thus proved a reliable, fast, accurate method for obtaining T2-weighted images, and may be of particular use in the restless, claustrophobic or obtunded patient.
Algorithms↗