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1.
J Dent Res ; 101(11): 1398-1407, 2022 10.
Article in English | MEDLINE | ID: mdl-35774010

ABSTRACT

Craniofacial structures change dynamically in morphology during development through the coordinated regulation of various cellular molecules. However, it remains unclear how these complex mechanisms are regulated in a spatiotemporal manner. Here we applied natural cubic splines to model gene and microRNA (miRNA) expression from embryonic day (E) 10.5 to E14.5 in the proximal and distal regions of the maxillary processes to identify spatiotemporal patterns of gene and miRNA expression, followed by constructing corresponding regulatory networks. Three major groups of differentially expressed genes (DEGs) were identified, including 3,927 temporal, 314 spatial, and 494 spatiotemporal DEGs. Unsupervised clustering further resolved these spatiotemporal DEGs into 8 clusters with distinct expression patterns. Interestingly, we found 2 clusters of differentially expressed miRNAs: 1 had 80 miRNAs monotonically decreasing and the other had 97 increasing across developmental stages. To evaluate the phenotypic relevance of these DEGs during craniofacial development, we integrated data from the CleftGeneDB database and constructed the regulatory networks of genes related to orofacial clefts. Our analysis revealed 2 hub miRNAs, mmu-miR-325-3p and mmu-miR-384-5p, that repressed cleft-related genes Adamts3, Runx2, Fgfr2, Acvr1, and Edn2, while their expression increased over time. On the contrary, 2 hub miRNAs, mmu-miR-218-5p and mmu-miR-338-5p, repressed cleft-related genes Pbx2, Ermp1, Snai1, Tbx2, and Bmi1, while their expression decreased over time. Our experiments indicated that these miRNA mimics significantly inhibited cell proliferation in mouse embryonic palatal mesenchymal (MEPM) cells and O9-1 cells through the regulation of genes associated with cleft palate and validated the role of our regulatory networks in orofacial clefts. To facilitate interactive exploration of these data, we developed a user-friendly web tool to visualize the gene and miRNA expression patterns across developmental stages, as well as the regulatory networks (https://fyan.shinyapps.io/facebase_shiny/). Taken together, our results provide a valuable resource that serves as a reference map for future research in craniofacial development.


Subject(s)
Cleft Lip , Cleft Palate , MicroRNAs , Animals , Cleft Lip/genetics , Cleft Palate/genetics , Core Binding Factor Alpha 1 Subunit , Gene Expression , Gene Expression Profiling , Gene Regulatory Networks/genetics , Mice , MicroRNAs/genetics , MicroRNAs/metabolism
2.
J Thromb Haemost ; 16(12): 2501-2514, 2018 12.
Article in English | MEDLINE | ID: mdl-30347494

ABSTRACT

Essentials The rs773902 SNP results in differences in platelet protease-activated receptor (PAR4) function. The functional consequences of rs773902 were analyzed in human platelets and stroke patients. rs773902 affects thrombin-induced platelet function, PAR4 desensitization, stroke association. Enhanced PAR4 Thr120 effects on platelet function are blocked by ticagrelor. SUMMARY: Background F2RL3 encodes protease-activated receptor (PAR) 4 and harbors an A/G single-nucleotide polymorphism (SNP) (rs773902) with racially dimorphic allelic frequencies. This SNP mediates an alanine to threonine substitution at residue 120 that alters platelet PAR4 activation by the artificial PAR4-activation peptide (PAR4-AP) AYPGKF. Objectives To determine the functional effects of rs773902 on stimulation by a physiological agonist, thrombin, and on antiplatelet antagonist activity. Methods Healthy human donors were screened and genotyped for rs773902. Platelet function in response to thrombin was assessed without and with antiplatelet antagonists. The association of rs773902 alleles with stroke was assessed in the Stroke Genetics Network study. Results As compared with rs773902 GG donors, platelets from rs773902 AA donors had increased aggregation in response to subnanomolar concentrations of thrombin, increased granule secretion, and decreased sensitivity to PAR4 desensitization. In the presence of PAR1 blockade, this genotype effect was abolished by higher concentrations of or longer exposure to thrombin. We were unable to detect a genotype effect on thrombin-induced PAR4 cleavage, dimerization, and lipid raft localization; however, rs773902 AA platelets required a three-fold higher level of PAR4-AP for receptor desensitization. Ticagrelor, but not vorapaxar, abolished the PAR4 variant effect on thrombin-induced platelet aggregation. A significant association of modest effect was detected between the rs773902 A allele and stroke. Conclusion The F2RL3 rs773902 SNP alters platelet reactivity to thrombin; the allelic effect requires P2Y12 , and is not affected by gender. Ticagrelor blocks the enhanced reactivity of rs773902 A platelets. PAR4 encoded by the rs773902 A allele is relatively resistant to desensitization and may contribute to stroke risk.


Subject(s)
Blood Platelets/drug effects , Pharmacogenomic Variants , Platelet Aggregation Inhibitors/pharmacology , Polymorphism, Single Nucleotide , Purinergic P2Y Receptor Antagonists/pharmacology , Receptors, Purinergic P2Y12/drug effects , Receptors, Thrombin/agonists , Receptors, Thrombin/genetics , Thrombin/pharmacology , Ticagrelor/pharmacology , Adult , Animals , Blood Platelets/metabolism , COS Cells , Chlorocebus aethiops , Drug Interactions , Female , HEK293 Cells , Humans , Male , Middle Aged , Platelet Aggregation/drug effects , Receptors, Purinergic P2Y12/metabolism , Receptors, Thrombin/metabolism , Risk Factors , Stroke/blood , Stroke/genetics , Young Adult
3.
Gigascience ; 7(6)2018 06 01.
Article in English | MEDLINE | ID: mdl-29901703

ABSTRACT

Background: With the advent of the age of big data in bioinformatics, large volumes of data and high-performance computing power enable researchers to perform re-analyses of publicly available datasets at an unprecedented scale. Ever more studies imply the microbiome in both normal human physiology and a wide range of diseases. RNA sequencing technology (RNA-seq) is commonly used to infer global eukaryotic gene expression patterns under defined conditions, including human disease-related contexts; however, its generic nature also enables the detection of microbial and viral transcripts. Findings: We developed a bioinformatic pipeline to screen existing human RNA-seq datasets for the presence of microbial and viral reads by re-inspecting the non-human-mapping read fraction. We validated this approach by recapitulating outcomes from six independent, controlled infection experiments of cell line models and compared them with an alternative metatranscriptomic mapping strategy. We then applied the pipeline to close to 150 terabytes of publicly available raw RNA-seq data from more than 17,000 samples from more than 400 studies relevant to human disease using state-of-the-art high-performance computing systems. The resulting data from this large-scale re-analysis are made available in the presented MetaMap resource. Conclusions: Our results demonstrate that common human RNA-seq data, including those archived in public repositories, might contain valuable information to correlate microbial and viral detection patterns with diverse diseases. The presented MetaMap database thus provides a rich resource for hypothesis generation toward the role of the microbiome in human disease. Additionally, codes to process new datasets and perform statistical analyses are made available.


Subject(s)
Disease/genetics , Metagenomics , Sequence Analysis, RNA , Software , Transcriptome/genetics , Humans , Lymphocytes/metabolism
4.
Pathology ; 46(5): 375-82, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24992243

ABSTRACT

Inherited metabolic diseases (IMDs) are a large group of rare genetic diseases. The spectrum and incidences of IMDs differ among populations, which has been well characterised in Caucasians but much less so in Chinese. In a setting of a University Hospital Metabolic Clinic in Hong Kong, over 100 patients with IMDs have been seen during a period of 13 years (from 1997 to 2010). The data were used to define the spectrum of diseases in the Southern Chinese population. Comparison with other populations revealed a unique spectrum of common IMDs. Furthermore, the incidence of the common IMDs was estimated by using population carrier frequencies of known recurrent mutations. Locally common diseases (their estimated incidence) include (1) glutaric aciduria type 1 (∼1/60,000), (2) multiple carboxylase deficiency (∼1/60,000), (3) primary carnitine deficiency (∼1/60,000), (4) carnitine-acylcarnitine translocase deficiency (∼1/60,000), (5) glutaric aciduria type 2 (∼1/22,500), (6) citrin deficiency (∼1/17,000), (7) tetrahydrobiopterin-deficient hyperphenylalaninaemia due to 6-pyruvoyl-tetrahydropterin synthase deficiency (∼1/60,000), (8) glycogen storage disease type 1 (∼1/150,000). In addition, ornithine carbamoyltransferase deficiency and X-linked adrenoleukodystrophy are common X-linked diseases. Findings of the disease spectrum and treatment outcome are summarised here which may be useful for clinical practice. In addition, data will also be useful for policy makers in planning of newborn screening programs and resource allocation.


Subject(s)
Asian People/genetics , Metabolism, Inborn Errors/epidemiology , Metabolism, Inborn Errors/genetics , China/epidemiology , Humans , Incidence , Mutation
5.
Hum Mutat ; 34(9): 1289-97, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23757194

ABSTRACT

A CA-repeat microsatellite in insulin-like growth factor 1 (IGF1) promoter was associated with interindividual variation of circulating IGF1 level. Previously, we reported that such association was due to variation of haplotype unit in a linkage disequilibrium block composed of microsatellite and single-nucleotide polymorphisms (SNPs), suggesting the presence of an interaction between them. In this study, reporter assays were performed to investigate the regulatory effect and interaction of genetic variants on gene expression. We used an in vitro system to compare the transcriptional activities of haplotypes (rs35767:T>C, the CA-repeat microsatellite, rs5742612:T>C, and rs2288377:T>A) in evolutionarily conserved region of IGF1 promoter. In haplotype C-T-T, a longer microsatellite had a lower transcriptional activity (17.6 ± 2.4-fold for 17 repeats and 8.3 ± 1.1-fold for 21 repeats), whereas in haplotype T-C-A, such trend could not be observed, as the microsatellite with 21 repeats had the highest transcriptional activity (17.5 ± 2.3-fold). Because the microsatellite and SNPs affected the transcriptional activity of each other, there may be an interaction between them in the regulation of IGF1 expression. For the first time, we demonstrated that a noncoding microsatellite polymorphism could act as a functional unit and interact with SNPs in the regulation of transcription in human genome.


Subject(s)
Insulin-Like Growth Factor I/genetics , Insulin-Like Growth Factor I/metabolism , Microsatellite Repeats , Polymorphism, Single Nucleotide , Base Sequence , Gene Expression Regulation , Genetic Variation , Genome, Human , Haplotypes , Humans , Linkage Disequilibrium , Molecular Sequence Data , Promoter Regions, Genetic
6.
Clin Chim Acta ; 404(2): 95-9, 2009 Jun 27.
Article in English | MEDLINE | ID: mdl-19265687

ABSTRACT

BACKGROUND: Multiple acyl-CoA dehydrogenase deficiency (MADD, OMIM 231680) or glutaric aciduria type II (GAII) is an inherited autosomal recessive disease affecting fatty acid, amino acid and choline metabolism, due to mutations in one of three genes namely, electron transfer flavoprotein alpha-subunit, ETFA (OMIM 608053), electron transfer flavoprotein beta-subunit, ETFB (OMIM 130410) and electron transfer flavoprotein dehydrogenase, ETFDH (OMIM 231675). Some MADD patients are responsive to riboflavin treatment with an excellent prognosis. Recently, mutations in ETFDH were found to be responsible for all riboflavin-responsive MADD patients. In this study, we present the clinical features and molecular studies of 2 Chinese families with riboflavin-responsive MADD. METHODS: Genomic DNA was extracted from peripheral blood samples or skin fibroblast cultures from the patients and normal controls. The thirteen exons of ETFDH were amplified by PCR. PCR products were sequenced in both forward and reverse directions. To rule out mutations in other genes, phenotype segregation was studied in the families by microsatellite markers in the proximity of the 3 genes, ETFA, ETFB and ETFDH. RESULTS: Four novel mutations in ETFDH were detected in the 2 families. In family 1, a frame shift mutation, c.1355delG which introduced a premature-termination codon (PTC), I454X in exon 11 of ETFDH was found. Another mutation was a c.250G>A transition in exon 3 of ETFDH, A84T. In family 2, two novel missense mutations were identified, P137S, in exon 4 and G467R in exon 11. No carrier of these four mutations was identified from about 150 alleles of healthy Chinese control subjects. CONCLUSIONS: Four novel mutations (3 missenses and 1 deletion) in ETFDH were found in Chinese families that presented with riboflavin-responsive MADD, which further expands the list of mutations found in patients with riboflavin-responsive MADD. Furthermore, we illustrated the utility of phenotype-genotype segregation in MADD families to prioritize genes for sequencing or to rule out the presence of disease causing mutation in other genes in MADD and other diseases caused by multiple genes.


Subject(s)
Electron-Transferring Flavoproteins/genetics , Iron-Sulfur Proteins/genetics , Multiple Acyl Coenzyme A Dehydrogenase Deficiency/drug therapy , Multiple Acyl Coenzyme A Dehydrogenase Deficiency/genetics , Oxidoreductases Acting on CH-NH Group Donors/genetics , Child, Preschool , China , DNA Mutational Analysis , Electron-Transferring Flavoproteins/drug effects , Exons/genetics , Female , Frameshift Mutation/genetics , Humans , Infant , Iron-Sulfur Proteins/drug effects , Microsatellite Repeats/genetics , Mutation, Missense/genetics , Oxidoreductases Acting on CH-NH Group Donors/drug effects , Riboflavin/therapeutic use , Young Adult
7.
Biochem Biophys Res Commun ; 317(2): 610-3, 2004 Apr 30.
Article in English | MEDLINE | ID: mdl-15063801

ABSTRACT

The effects of polyethylene glycol (PEG) of different molecular weights (400, 2000, 6000, 12,000, 20,000, and 35,000) on the conformational stability and catalytic activity of alpha-chymotrypsin in 60% ethanol were studied. The inactivation caused by the organic solvent was not influenced by PEG 400. However, the PEGs with higher molecular weights up to 35,000 increased the stability of the enzyme, but this alpha-chymotrypsin stabilizing effect was molecular weight-independent. With increase of the molecular weight of PEG, a more stable tertiary structure of the enzyme was observed.


Subject(s)
Chymotrypsin/chemistry , Ethanol/chemistry , Polyethylene Glycols/chemistry , Solvents/chemistry , Water/chemistry , Enzyme Activation , Enzyme Stability , Hydrogen-Ion Concentration , Molecular Weight , Protein Structure, Tertiary
8.
Biochem Biophys Res Commun ; 304(1): 18-21, 2003 Apr 25.
Article in English | MEDLINE | ID: mdl-12705877

ABSTRACT

The effects of calcium ions on the conformation and catalytic activity of trypsin and alpha-chymotrypsin were studied in aqueous ethanol. The activity of alpha-chymotrypsin was practically lost within 10 min in the presence of 60% ethanol while trypsin preserved about 40% of its original activity even in 85% ethanol at pH 3. The catalytic activity of alpha-chymotrypsin did not decrease in the presence of 1.2M CaCl2 and 0.6M CaCl2 with trypsin in ethanolic solvent. In the latter case an activation of enzyme was observed. The stabilizing effects of calcium ions were accompanied by an increase in the helical content in both enzymes, as followed by circular dichroism measurements.


Subject(s)
Calcium/pharmacology , Chymotrypsin/chemistry , Chymotrypsin/metabolism , Trypsin/chemistry , Trypsin/metabolism , Catalysis/drug effects , Circular Dichroism , Enzyme Stability/drug effects , Ethanol/chemistry , Protein Conformation/drug effects , Solvents/chemistry , Water/chemistry
9.
Clin Biochem ; 36(2): 145-9, 2003 Mar.
Article in English | MEDLINE | ID: mdl-12633764

ABSTRACT

OBJECTIVE: Multiple carboxylase deficiency (MCD, MIM:253270) is a common organic aciduria and caused by deficiency of either biotinidase or holocarboxylase synthetase (HLCS; EC 6.3.4.10). Patients commonly present during early infancy with acute metabolic derangements and severe metabolic acidosis. Recently, a late onset form of HLCS deficiency was also described. The different phenotypes (early and late presenting) may be related to a spectrum of mutations in HLCS gene. Applications of mutation analysis in HLCS had been limited previously by the requirement of cDNA from living tissue for study. We described here a genomic approach for molecular diagnosis of HLCS deficiency which we have used to detect mutations in Chinese patients who had the late-onset form of HLCS deficiency. In addition, a fibroblast cell line with MCD from Coriell Cell repositories was also studied. DESIGN AND METHODS: Three Chinese patients with late onset HLCS deficiency were studied. The genomic sequence of HLCS was retrieved and newly designed primers were used to cover all coding sequences of the gene. PCR products were analyzed by direct sequencing. Population allelic frequencies of mutations detected were determined by genotyping of control samples by restriction fragment length polymorphism. RESULTS: We found a recurrent mutation, R508W, in the three unrelated Chinese patients. Two were homozygous for this mutation. The other patient was a compound heterozygote of R508W and a novel mutation, D634N. The results suggest that R508W may be an important and relatively prevalent disease-causing mutation in Chinese MCD patients. A fibroblast cell-line from an African patient revealed an additional novel mutation, R565X and a known mutation, V550M. CONCLUSION: R508W is a recurrent mutation in Chinese MCD patients which is associated with the late onset phenotype. This new genomic approach for mutation analysis of HLCS gene provides new opportunities in studies of MCD.


Subject(s)
Carbon-Nitrogen Ligases/genetics , DNA Mutational Analysis/methods , Holocarboxylase Synthetase Deficiency/genetics , Asian People , Base Sequence , Cell Line, Transformed , Child, Preschool , DNA Primers/genetics , Exons , Female , Fibroblasts/cytology , Heterozygote , Homozygote , Humans , Infant , Male , Phenotype , Point Mutation , Polymorphism, Restriction Fragment Length
10.
Biochem Biophys Res Commun ; 293(1): 416-20, 2002 Apr 26.
Article in English | MEDLINE | ID: mdl-12054616

ABSTRACT

The effects of glycerol, polyethylene glycol, fructose, glucose, sorbitol, and saccharose on the conformation and catalytic activity of alpha-chymotrypsin were studied in 0.1 M sodium phosphate buffer and buffered aqueous 60% ethanol (pH 8.0). The enzyme activity was practically completely lost within 10 min in 60% ethanol, but in the presence of stabilizers the activity was retained. With the exception of polyethylene glycol, the stabilizing effect decreased with increase of the incubation time. The preservation of the catalytic activity was accompanied by changes in the secondary and tertiary structures of alpha-chymotrypsin.


Subject(s)
Chymotrypsin/chemistry , Chymotrypsin/metabolism , Animals , Cattle , Circular Dichroism , Fructose/pharmacology , Glucose/pharmacology , Glycerol/pharmacology , Kinetics , Polyethylene Glycols/pharmacology , Protein Conformation/drug effects , Sorbitol/pharmacology , Spectrophotometry, Ultraviolet , Sucrose/pharmacology
11.
Biochem Biophys Res Commun ; 280(5): 1367-71, 2001 Feb 09.
Article in English | MEDLINE | ID: mdl-11162681

ABSTRACT

The effects of different concentrations (20-95%) of organic solvents (ethanol, 1,4-dioxane and acetonitrile) were studied on alpha-chymotrypsin and trypsin from bovine pancreas. The changes in secondary structure were followed by CD measurements, and the apparent Michaelis constants (KMapp) and the stabilities of the enzymes were determined. Significant alterations in the CD spectra were found for both enzymes at the different organic solvent concentrations. The apparent KM values of trypsin and alpha-chymotrypsin decreased as the low solvent concentrations were elevated, but then increased in the presence of higher organic solvent concentrations. The stabilities of the enzymes changed on increase of the organic solvent concentration; trypsin exhibited a higher stability than that of alpha-chymotrypsin in all organic solvents. These results show that at an organic solvent content of 95% the manifestation of an enzyme activity similar to that measured in water can be attributed to the similar compositions of the secondary structural elements.


Subject(s)
Chymotrypsin/chemistry , Organic Chemicals/chemistry , Trypsin/chemistry , Acetonitriles/chemistry , Acetonitriles/pharmacology , Animals , Cattle , Chymotrypsin/drug effects , Chymotrypsin/metabolism , Circular Dichroism , Dioxanes/chemistry , Dioxanes/pharmacology , Dose-Response Relationship, Drug , Enzyme Stability/drug effects , Ethanol/chemistry , Ethanol/pharmacology , Hydrogen-Ion Concentration , Organic Chemicals/pharmacology , Protein Structure, Secondary/drug effects , Solvents/chemistry , Solvents/pharmacology , Structure-Activity Relationship , Trypsin/drug effects , Trypsin/metabolism
13.
Behav Sci Law ; 18(2-3): 275-308, 2000.
Article in English | MEDLINE | ID: mdl-10874290

ABSTRACT

Sex offenders have been singled out for differential treatment by the legal and mental health systems. This article attempts to inform law reform efforts and criminal justice mental health policy by examining the assumptions underlying differential legal and mental health treatment of sex offenders. These assumptions include the theories that sex offenders are mentally disordered and in need of treatment, specialists in sex crimes, and more dangerous than other criminal offenders. Empirical findings demonstrate that sex offenders are not specialists in sex crimes and are not mentally disordered. Examination of past research suggests that sex offenders are not at more risk than other criminal offenders to commit future sex crimes. Implications of research findings for selective prosecution of sex crime cases, mental health policy, sex offender legislation, and predictions of future dangerousness are discussed. Proposals for future research needs and law reform are presented.


Subject(s)
Dangerous Behavior , Mental Disorders/diagnosis , Sex Offenses/legislation & jurisprudence , Adult , Child , Commitment of Mentally Ill/legislation & jurisprudence , Expert Testimony/legislation & jurisprudence , Female , Health Policy/legislation & jurisprudence , Humans , Male , Mental Disorders/psychology , Recurrence , Sex Offenses/psychology , United States
14.
J Environ Sci Health B ; 34(5): 819-28, 1999 Sep.
Article in English | MEDLINE | ID: mdl-10466103

ABSTRACT

The effects of pyrethroid pesticides (deltamethrin, permethrin and cypermethrin) and an organophosphate ester (methidation) on the activities of carp trypsin, alpha-chymotrypsin, carboxypeptidase A and lipase were studied. The enzymes were isolated from the gastrointestinal tract and the effects of the pesticides were investigated during incubation for 5 min. The activity of trypsin was influenced only slightly by the presence of deltamethrin and methidation, whereas permethrin and cypermethrin caused significant inhibition. The pyrethroid pesticides at lower concentrations resulted in a slight activation of alpha-chymotrypsin. Methidation inhibited the alpha-chymotrypsin activity by about 20%. These pesticides modified the lipase activity to a lesser extent; the highest inhibition was measured with cypermethrin. The carboxypeptidase A activity was inhibited by both pyrethroid pesticides and methidation. The results suggest that these pesticides might interact with the active conformation of the studied hydrolytic enzymes, resulting in changes in their activities.


Subject(s)
Carboxypeptidases/metabolism , Carps/metabolism , Chymotrypsin/metabolism , Industrial Waste/adverse effects , Insecticides/toxicity , Lipase/metabolism , Trypsin/metabolism , Water Pollution, Chemical/adverse effects , Animals , Carboxypeptidases A , Digestion/drug effects , Nitriles , Organothiophosphorus Compounds/toxicity , Permethrin , Pyrethrins/toxicity
15.
J Biotechnol ; 66(1): 75-82, 1998 Nov 18.
Article in English | MEDLINE | ID: mdl-9866861

ABSTRACT

The carboxypeptidase A-catalyzed syntheses of dipeptides from L-amino acids (Phe, Tyr, Trp, Leu and Ile) were studied in various water-miscible (acetone, acetonitrile, ethanol, methanol and 1,4-dioxane) organic solvents. The highest yield (43%) was achieved in acetonitrile with L-Phe as substrate, after a 24-h incubation. The optimal conditions of Phe-Phe synthesis in acetonitrile were determined. For maximal conversion 1.2 mM L-Phe, 1.4 mg ml-1 enzyme and about 10% water are needed in buffered aqueous acetonitrile (pH 5.5) at 30 degrees C.


Subject(s)
Biochemistry/methods , Carboxypeptidases/chemistry , Carboxypeptidases/metabolism , Dipeptides/chemical synthesis , Acetonitriles , Carboxypeptidases A , Dipeptides/metabolism , Phenylalanine/chemistry , Solvents
16.
Am J Sports Med ; 24(1): 88-93, 1996.
Article in English | MEDLINE | ID: mdl-8638760

ABSTRACT

A descriptive study was conducted to investigate injuries sustained at a major off-road bicycling race at Mammoth Mountain, California, July 6 to 10, 1994. A total of 4027 individual starts in five events during the race were reported. Overall, the total number of competitors in the 5 events was 3624, with some cyclists participating in multiple events. Injuries were considered significant if they occurred during competition and prevented the rider from completing the event. Sixteen cyclists had injuries that met these criteria for an overall injury rate of 0.40%. These 16 cyclists had 44 injuries. Abrasions were the most common injury, followed by contusions, lacerations, fractures, and concussions. The mean injury severity score was 3.0 (range, 1 to 5) with 81.2% of the injuries resulting from cyclists going downhill. Injuries were more severe when the riders were thrown from the bicycles (P = 0.03). We observed different mechanisms of injury in various events, suggesting that the risk factors for sustaining a traumatic injury may vary according to the type of competition involved.


Subject(s)
Bicycling/injuries , Adolescent , Adult , Arm Injuries/epidemiology , Athletic Injuries/epidemiology , Brain Concussion/epidemiology , California/epidemiology , Child , Contusions/epidemiology , Female , Fractures, Bone/epidemiology , Humans , Injury Severity Score , Leg Injuries/epidemiology , Male , Middle Aged , Protective Devices , Risk Factors , Skin/injuries
17.
Enzyme Microb Technol ; 16(11): 974-8, 1994 Nov.
Article in English | MEDLINE | ID: mdl-7765412

ABSTRACT

Glucose-6-phosphate dehydrogenase (D-glucose-6-phosphate: NADP+ 1-oxidoreductase, EC 1.1.1.49) from Bakers' yeast was immobilized with the highest activity on polyacrylamide beads possessing carboxylic functional groups activated by a water-soluble carbodiimide. The optimal pH values for the catalytic activity of the soluble and the immobilized glucose-6-phosphate dehydrogenase were practically identical, lying between pH 9.0 and 9.2. The optimal temperature for both the soluble and the immobilized enzyme was about 50 degrees C. The apparent Km values of the immobilized enzyme were slightly higher than those of the soluble enzyme. The immobilization improved the stability of the enzyme in the pH range 6.0-9.0 at 45 degrees C. The operational stability of the immobilized glucose-6-phosphate dehydrogenase proved favorable in a column experiment during 37 days of operation.


Subject(s)
Glucosephosphate Dehydrogenase/isolation & purification , Saccharomyces cerevisiae/enzymology , CME-Carbodiimide/chemistry , Enzyme Stability , Enzymes, Immobilized/isolation & purification , Enzymes, Immobilized/metabolism , Glucosephosphate Dehydrogenase/metabolism , Hydrogen-Ion Concentration , NADP/metabolism , Temperature
18.
Acta Biochim Biophys Hung ; 25(1-2): 1-7, 1990.
Article in English | MEDLINE | ID: mdl-2151836

ABSTRACT

Yeast alcohol dehydrogenase (alcohol: NAD+ oxidoreductase, EC 1.1.1.1) was adsorbed onto polyethylene terephthalate, a synthetic polymer. The effects of the polymer on the properties of the enzyme were studied. The specific activity of the bound enzyme on protein basis was only 1.2 per cent of the specific activity of the soluble enzyme. The optimum pH for the catalytic activity was strongly shifted toward acidic direction. The apparent temperature optimum of the bound enzyme was identical with that of the soluble form. The apparent Michaelis constants of the bound enzyme were higher for both ethanol and NAD+. The conformational stability of the enzyme against heat treatment and urea was decreased as a consequence of adsorption.


Subject(s)
Alcohol Dehydrogenase/metabolism , Enzymes, Immobilized , Polyethylene Terephthalates/pharmacology , Yeasts/enzymology , Adsorption , Alcohol Dehydrogenase/antagonists & inhibitors , Ethanol/metabolism , Hydrogen-Ion Concentration , Kinetics , NAD/metabolism , Temperature , Urea/pharmacology
19.
Surg Gynecol Obstet ; 167(2): 92-8, 1988 Aug.
Article in English | MEDLINE | ID: mdl-3041636

ABSTRACT

The physiopathologic similarity between adult respiratory distress syndrome (ARDS) secondary to sepsis and endotoxin-induced pulmonary abnormalities has provided extensive descriptive information confirming bacterial endotoxin as a factor initiating the heterogeneous pulmonary changes in ARDS. The present studies have used an established in vitro model for pulmonary cell injury to examine bacterial endotoxin 1, as a direct cytotoxic agent on the two major alveolar cell types, pulmonary endothelium and epithelium; 2, as a stimulant of neutrophil-mediated pulmonary cell injury, and 3, to examine effector mechanisms of cell-mediated damage by studying the potential effectiveness of antioxidants and antiproteolytic agents in the inhibition of this process. Endotoxin direct toxicity and stimulation of neutrophil-mediated pulmonary cell injury was observed in both pulmonary cell populations in systems free of activated serum complement. Endothelial cells were observed to be more susceptible to both the direct effect of endotoxin and to neutrophil-mediated injury when compared with epithelial cell derived monolayers. The addition of an antiprotease (soybean trypsin inhibitor [STI]) was superior to antioxidants (catalase, superoxide dismutase) in reducing the neutrophil-mediated endothelial toxicity (stimulated 51CR per cent release) observed. A 92 per cent degree of protection was observed with the highest dose of STI (5 milligrams per milliliter) used. Proteases released by activated neutrophils on endotoxin stimulation appear to be the predominant toxic species responsible for endothelial injury in this system.


Subject(s)
Endotoxins/toxicity , Lung/drug effects , Antioxidants/pharmacology , Cell Survival/drug effects , Cells, Cultured , Endothelium, Vascular/drug effects , Endothelium, Vascular/physiology , Epithelium/drug effects , Epithelium/physiology , Escherichia coli , Humans , Lung/physiology , Neutrophils/physiology , Respiratory Distress Syndrome/physiopathology , Trypsin Inhibitors/pharmacology
20.
Acta Biochim Biophys Hung ; 23(3-4): 247-54, 1988.
Article in English | MEDLINE | ID: mdl-3150193

ABSTRACT

Some glycolytic enzymes (lactate dehydrogenase, pyruvate kinase, enolase and phosphoglyceromutase) were immobilized on a polyacrylamide-type bead polymer containing carboxylic functional groups activated by water-soluble carbodiimide. The immobilized enzymes were used for the determination of pyruvic acid, phosphoenolpyruvic acid, 2-phosphoglyceric acid and 3-phosphoglyceric acid in a flow injection system. The immobilized lactate dehydrogenase column was repeatedly employed for the determination of pyruvic acid in clinical samples. The results of the flow injection method accorded well in accuracy, sensitivity and reproducibility with those of soluble enzyme analysis.


Subject(s)
Enzymes, Immobilized/metabolism , Glyceric Acids/analysis , Phosphoenolpyruvate/analysis , Enzyme Stability , Glycolysis , Humans , Microspheres , Pyruvates/analysis , Pyruvates/blood , Pyruvic Acid
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