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1.
Appl Microbiol Biotechnol ; 108(1): 349, 2024 May 29.
Article in English | MEDLINE | ID: mdl-38809317

ABSTRACT

Galacto-oligosaccharides (GOS) are prebiotic compounds that are mainly used in infant formula to mimic bifidogenic effects of mother's milk. They are synthesized by ß-galactosidase enzymes in a trans-glycosylation reaction with lactose. Many ß-galactosidase enzymes from different sources have been studied, resulting in varying GOS product compositions and yields. The in vivo role of these enzymes is in lactose hydrolysis. Therefore, the best GOS yields were achieved at high lactose concentrations up to 60%wt, which require a relatively high temperature to dissolve. Some thermostable ß-glucosidase enzymes from thermophilic bacteria are also capable of using lactose or para nitrophenyl-galactose as a substrate. Here, we describe the use of the ß-glucosidase BglA from Thermotoga maritima for synthesis of oligosaccharides derived from lactose and cellobiose and their detailed structural characterization. Also, the BglA enzyme kinetics and yields were determined, showing highest productivity at higher lactose and cellobiose concentrations. The BglA trans-glycosylation/hydrolysis ratio was higher with 57%wt lactose than with a nearly saturated cellobiose (20%wt) solution. The yield of GOS was very high, reaching 72.1%wt GOS from lactose. Structural elucidation of the products showed mainly ß(1 → 3) and ß(1 → 6) elongating activity, but also some ß(1 → 4) elongation was observed. The ß-glucosidase BglA from T. maritima was shown to be a very versatile enzyme, producing high yields of oligosaccharides, particularly GOS from lactose. KEY POINTS: • ß-Glucosidase of Thermotoga maritima synthesizes GOS from lactose at very high yield. • Thermotoga maritima ß-glucosidase has high activity and high thermostability. • Thermotoga maritima ß-glucosidase GOS contains mainly (ß1-3) and (ß1-6) linkages.


Subject(s)
Cellobiose , Lactose , Oligosaccharides , Thermotoga maritima , beta-Glucosidase , Thermotoga maritima/enzymology , Thermotoga maritima/genetics , Lactose/metabolism , Cellobiose/metabolism , beta-Glucosidase/metabolism , beta-Glucosidase/genetics , beta-Glucosidase/chemistry , Kinetics , Oligosaccharides/metabolism , Glycosylation , Hydrolysis , Temperature , Enzyme Stability
2.
Psychotherapy (Chic) ; 2024 May 30.
Article in English | MEDLINE | ID: mdl-38815118

ABSTRACT

The purpose of this study was to examine associations between clinicians' use of varying types of spiritual interventions in the first session of spiritually integrated psychotherapies (SIPs) and clients' likelihood of returning for a second session. In total, 154 practitioners of SIPs from 33 settings in a practice-research network reported on their implementation of different methods for addressing clients' religion/spirituality on an after-session summary checklist. Roughly 80% or more of the clinicians implemented at least one spiritual intervention in the first session; on average, clinicians used 3.26 (SD = 3.66) of the interventions on the checklist. Occurring with 20% or more of the 1,094 clients, the most commonly used spiritual interventions included listening to spiritual issues, discussing compassion and hope, affirming clients' divine worth and attempts to trust God. In total, nearly one in five clients did not return for a second session. Focusing on interventions that were empirically linked with clients' engagement in a second session in bivariate analyses, discussion of spiritual dimensions of clients' problems and solutions was associated with a 118% greater probability that clients engaged in SIPs; in contrast, discussion of hope was linked with a 40% decrease in treatment engagement. In conclusion, findings highlight the potential opportunities and risks for implementing interventions that attend to clients' spirituality and/or religious faith at the start of SIPs. Research is needed to understand factors associated with the effective use of spiritual interventions and methods of training clinicians accordingly. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

3.
J Couns Psychol ; 71(4): 291-303, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38358673

ABSTRACT

The aims of this practice-based evidence study were to (a) examine clients' trajectories of psychological and spiritual distress over the course of spiritually integrated psychotherapies (SIPs) and (b) explore the role of varying types of spiritual interventions in these outcomes. In total, 164 practitioners of SIPs from 37 settings in a practice-research network administered the Clinically Adaptive Multidimensional Outcome Survey (Sanders et al., 2018) at each session with 1,227 clients and reported their use of theoretical orientations and spiritual interventions on an after-session summary checklist. Focusing on sessions over an initial 12-week period, latent growth curve modeling analyses revealed that clients, on average, experienced significant reduction of psychological distress during their engagement in SIPs with improvements occurring most sharply in the first month. Further, other findings revealed a salient reciprocal interplay with spiritual distress throughout treatment, such that clients who were struggling with their religious faith and/or spirituality were more psychologically distressed and displayed a more attenuated and gradual pattern of symptom reduction. In such cases, clinicians frequently utilized spiritual interventions involving basic skills (e.g., spiritual assessment), virtues (e.g., discuss self-control), and religious attachment (e.g., encourage acceptance of divine love) that were uniquely associated with clients' rate and duration of decline in psychological and spiritual distress. The present findings affirm the routine effectiveness of SIPs along with highlighting the potential value of certain spiritual interventions in supporting holistic recovery among clients who want clinicians to be culturally responsive to their spiritual and/or religious identities. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Subject(s)
Psychological Distress , Psychotherapy , Spirituality , Humans , Female , Male , Adult , Psychotherapy/methods , Middle Aged , Evidence-Based Practice , Spiritual Therapies/methods
4.
Ann Otol Rhinol Laryngol ; 131(6): 579-586, 2022 Jun.
Article in English | MEDLINE | ID: mdl-34282649

ABSTRACT

OBJECTIVE: This study examined whether speech-language pathologist auditory-perceptual voice assessments can predict the medical urgency of voice disorders. METHODS: Twenty speech-language pathologists (SLPs) evaluated 25 voice samples recorded during initial voice evaluations. Voice samples represented a range of dysphonia severity (mild-severe) balanced across patient diagnoses. Diagnoses included: benign lesions, laryngeal cancer, non-organic voice disorders, laryngeal edema (associated with LPR), and laryngeal paralysis or paresis. Laryngeal cancer and severe unilateral laryngeal paralysis were considered urgent disorders. While blinded to patient information, SLPs rated severity of voice quality, predicted patient diagnosis, and determined whether the patient should be seen urgently by a laryngologist. SLPs were then given basic medical history information and rated medical urgency of voice disorder a second time. RESULTS: On average, SLPs correctly identified 65% of urgent voices and 87% of nonurgent voices when blinded to patient information. Accuracy improved significantly to 86% for urgent voices with medical history information (P < .001) and decreased to 77% for nonurgent voices. Accuracy was better when severity of voice quality was severe for urgent voices and mild for nonurgent voices (P < .001). SLPs indicated that patient smoking history and severity of dysphonia were most influential in their decision making. Diagnostic accuracy of auditory-perceptual assessments was poor. CONCLUSIONS: SLPs identified 86% of medically urgent voice disorders when auditory perceptual assessments were combined with medical history information. Further work is needed to determine what medical history information is most crucial to rating accuracy and what speech tasks might best separate urgent and nonurgent patients.


Subject(s)
Dysphonia , Laryngeal Neoplasms , Vocal Cord Paralysis , Voice Disorders , Dysphonia/diagnosis , Humans , Pathologists , Reproducibility of Results , Severity of Illness Index , Speech , Speech Acoustics , Speech Production Measurement , Voice Disorders/diagnosis
5.
J Voice ; 2021 Aug 31.
Article in English | MEDLINE | ID: mdl-34479778

ABSTRACT

BACKGROUND/OBJECTIVES: Growing reliance on telemedicine has created new triaging challenges. This study investigated how effectively otolaryngology resident auditory-perceptual voice assessments performed via telemedicine determined the need for urgent in-person clinic visits. METHODS: Twelve otolaryngology resident physicians (PGY1-PGY5) performed auditory-perceptual assessments on 25 voice samples recorded during initial voice evaluations. Voice samples were balanced in severity and taken in equal numbers from patients with the following diagnoses: benign laryngeal lesions, laryngeal cancer, functional voice disorders, laryngeal edema (associated with LPR), and laryngeal paralysis/paresis. Urgent diagnoses were defined as laryngeal cancer and severe unilateral laryngeal paralysis. For each voice sample, residents were initially blinded to patient medical history. Residents rated severity of voice disorder, predicted patient diagnosis, and determined the urgency of seeing the patient in clinic. Residents then reviewed information from the patient's medical history and again rated urgency of voice disorder. RESULTS: On average, residents identified urgent voice disorders in 56% of cases. After reviewing medical history, this number significantly increased to 77% (P = 0.001). Voice severity, smoking history, time since onset, and course of symptoms were considered most influential when determining medical urgency of voice patients. Year in residency program had no effect on rating accuracy. As expected, diagnostic accuracy of auditory-perceptual assessments was low, ranging from 40% for laryngeal paralysis/paresis to 5% for laryngeal edema. CONCLUSION: Auditory-perceptual voice assessment, combined with medical history, predicted most medically urgent voice disorders. Further work should investigate if task-specific training might improve these results and which medical history items are most critical. Until accuracy of auditory-perceptual assessment of medical urgency is improved, these data underscore the importance of laryngeal examination in identifying medical urgency and etiology of dysphonia.

6.
J AOAC Int ; 104(3): 732-756, 2021 Jun 12.
Article in English | MEDLINE | ID: mdl-34059909

ABSTRACT

BACKGROUND: In this international Multi-Laboratory Trial (MLT) the precision data and the accuracy of the ISO/CD 22184 IDF/WD 244 analytical method for the quantification of 6 different mono- and disaccharides (galactose, glucose, fructose, sucrose, lactose, and maltose) in milk and milk products with high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD) are established. OBJECTIVE: Thirteen different laboratories participated (located in New Zealand, the United States, and Europe). The study was divided into two parts. First, the learning/familiarization part in which the participants got experienced with the method. After successfully completing this part, the participants were allowed to continue with the second part of this trial: the analyses of the seven blind MLT duplicate samples. METHOD: The selected seven MLT samples comprise five MUVA reference dairy samples, one NIST-certified infant formula and one industrial sample. In the Tables S-1 to S-6 the results of this MLT study have been summarized per sugar. There is a very good agreement between the MUVA and NIST-certified sugar contents in the MLT samples and in the MLT established sugar contents in those MUVA and NIST samples. RESULTS: This demonstrates that the accuracy of the newly developed HPAEC-PAD method is very good. CONCLUSIONS: Certificates of analysis were available for both the MUVA samples and the NIST sample. There is a very good agreement between the by MUVA- and NIS-certified sugar contents in the MLT samples and the corresponding in the MLT established sugar contents. This demonstrates that the accuracy of the HPAEC-PAD method is very good. In the IDF/ISO Analytical Week in June 2019 in Prague the report on the MLT study were discussed and adopted.


Subject(s)
Laboratories , Milk , Animals , Anions , Chromatography, High Pressure Liquid , Chromatography, Ion Exchange , Europe , Humans , New Zealand , Sugars
7.
Bioinformatics ; 37(22): 4056-4063, 2021 11 18.
Article in English | MEDLINE | ID: mdl-34037680

ABSTRACT

MOTIVATION: Phylogenetic trees are now routinely inferred on large scale high performance computing systems with thousands of cores as the parallel scalability of phylogenetic inference tools has improved over the past years to cope with the molecular data avalanche. Thus, the parallel fault tolerance of phylogenetic inference tools has become a relevant challenge. To this end, we explore parallel fault tolerance mechanisms and algorithms, the software modifications required and the performance penalties induced via enabling parallel fault tolerance by example of RAxML-NG, the successor of the widely used RAxML tool for maximum likelihood-based phylogenetic tree inference. RESULTS: We find that the slowdown induced by the necessary additional recovery mechanisms in RAxML-NG is on average 1.00 ± 0.04. The overall slowdown by using these recovery mechanisms in conjunction with a fault-tolerant Message Passing Interface implementation amounts to on average 1.7 ± 0.6 for large empirical datasets. Via failure simulations, we show that RAxML-NG can successfully recover from multiple simultaneous failures, subsequent failures, failures during recovery and failures during checkpointing. Recoveries are automatic and transparent to the user. AVAILABILITY AND IMPLEMENTATION: The modified fault-tolerant RAxML-NG code is available under GNU GPL at https://github.com/lukashuebner/ft-raxml-ng. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Subject(s)
Phylogeny , User-Computer Interface , Algorithms , Software
8.
J AOAC Int ; 103(5): 1301-1317, 2020 Sep 01.
Article in English | MEDLINE | ID: mdl-33241403

ABSTRACT

BACKGROUND: Fructans are added to infant formula and adult nutritionals for their prebiotic effect. A method (AOAC 2016.14) was developed for their analysis which has already demonstrated excellent performance during single laboratory validation. OBJECTIVE: To determine repeatability and reproducibility of the method through a collaborative study. METHODS: Fourteen laboratories from 11 different countries enrolled for the study. Participants analyzed a practice sample, then 8 formula or adult nutritionals in blind duplicate. Results and any method modifications were reported to the study director. RESULTS: Twelve laboratories provided results on time for reporting. Precision results for five samples met the requirements of the Standard Method Performance Requirements (SMPR 2014.002), with RSDr ranging from 3.60 to 4.25% and RSDR ranging from 5.90 to 11.7%. The practice sample also met the requirements of SMPR 2014.002, with RSDr and RSDR of 2.53% and 6.70% respectively. Precision results for three test samples did not fully meet the SMPR, with RSDr ranging from 2.27 to 7.65% and RSDR ranging from 12.8 to 15.1%. After review, the AOAC Stakeholder Panel for Infant Formula and Adult Nutritional Expert Review Panel (SPIFAN ERP) concluded that the data presented mostly met the SMPR and hence recommended that the method to be advanced for adoption as an AOAC Final Action method. CONCLUSIONS: The method described in AOAC 2016.14 is suitable for the determination of fructans in infant formula and adult nutritionals.


Subject(s)
Fructans , Infant Formula , Adult , Anions , Child , Chromatography , Food, Formulated/analysis , Humans , Infant , Infant Formula/analysis , Reproducibility of Results
9.
J AOAC Int ; 2020 Jul 21.
Article in English | MEDLINE | ID: mdl-34585725

ABSTRACT

BACKGROUND: In this international Multi Laboratory Trial (MLT) the precision data and the accuracy of the ISO/CD 22184 IDF/WD 244 analytical method for the quantification of 6 different mono- and disaccharides (galactose, glucose, fructose, sucrose, lactose and maltose) in milk and milk products with high performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD) are established. OBJECTIVE: Thirteen different laboratories participated (located in New Zealand, United States, Europe). The study was divided into two parts. Firstly, the learning/familiarization part in which the participants got experienced with the method. After successfully completing this part, the participants were allowed to continue with the second part of this trial: the analyses of the seven blind MLT duplicate samples. METHOD: The selected seven MLT samples comprise five MUVA reference dairy samples, one NIST certified infant formula and one industrial sample. In the Tables S-1 to S-6 the results of this MLT study have been summarized per sugar. There is a very good agreement between the MUVA and NIST certified sugar contents in the MLT samples and the in the MLT established sugar contents in those MUVA and NIST samples. RESULTS: This demonstrates that the accuracy of the newly developed HPAEC-PAD method is very good. CONCLUSIONS: Certificates of analysis were available for both the MUVA samples and the NIST sample. There is a very good agreement between the by MUVA and NIS certified sugar contents in the MLT samples and the corresponding in the MLT established sugar contents. This demonstrates that the accuracy of the HPAEC-PAD method is very good.In the IDF/ISO Analytical Week in June 2019 in Prague the report on the MLT study were discussed and adopted.

10.
Psychother Res ; 28(6): 925-939, 2018 11.
Article in English | MEDLINE | ID: mdl-28100133

ABSTRACT

OBJECTIVE: Routine outcome monitoring (ROM) has been strongly endorsed by psychotherapy researchers, but has yet to achieve widespread implementation in clinical settings. This article describes the development of the Clinically Adaptive Multidimensional Outcome Survey (CAMOS), an innovative ROM system that allows for local adaptation while providing high quality data. METHOD: Three-hundred and four clients at a university counseling center and 211 female patients at an eating disorder treatment facility were administered the CAMOS at intake, and 118 took the CAMOS at both intake and discharge. Two models were developed and compared. Both models were developed using exploratory and confirmatory factor analysis. RESULTS: A five-factor model was found to have the best model fit, internal consistency, convergent validity, and discriminant validity. CONCLUSIONS: The CAMOS has evidence to support its reliability and validity as a measure of various dimensions of distress. Distinctive tailoring features of the CAMOS compared to other ROM measures are described.


Subject(s)
Mental Disorders/therapy , Models, Statistical , Outcome Assessment, Health Care/methods , Psychometrics/methods , Psychotherapy , Adult , Evidence-Based Practice , Factor Analysis, Statistical , Feeding and Eating Disorders/therapy , Female , Humans , Male , Middle Aged , Outcome Assessment, Health Care/standards , Psychometrics/instrumentation , Psychometrics/standards , Psychotherapy/statistics & numerical data , Reproducibility of Results , Young Adult
12.
J AOAC Int ; 100(5): 1577-1581, 2017 Sep 01.
Article in English | MEDLINE | ID: mdl-28492132

ABSTRACT

A method using high-performance anion-exchange chromatography (HPAEC) with a pulsed amperometric detector (PAD) for the determination of mono- and disaccharides is described. The method was accepted by the International Dairy Federation and the Internal Organization for Standardization as a new work item for the determination of sugars in dairy matrixes, and the Milk and Milk Products technical committee of ISO/TC 34/SC 5 accepted the topic "Milk and milk products - Determination of the sugar contents - High-performance anion-exchange chromatographic method (HPAEC-PAD)" as a new work item. The proposed method consists of an aqueous ethanol extraction of the sugars in the dairy sample, followed by clarification with Carrez I and II reagents. The clarified filtrate is diluted and then directly introduced in the HPAEC-PAD system for quantification of the sugars. A single-laboratory validation of the proposed method has been scheduled for spring 2017.


Subject(s)
Carbohydrates/analysis , Chromatography, High Pressure Liquid/standards , Chromatography, Ion Exchange/standards , Dairy Products/analysis , Milk/chemistry , Animals
13.
J AOAC Int ; 100(3): 753-767, 2017 May 01.
Article in English | MEDLINE | ID: mdl-28271820

ABSTRACT

Until recently, only two AOAC Official MethodsSM have been available for the analysis of fructans: Method 997.08 and Method 999.03. Both are based on the analysis of the fructan component monosaccharides (glucose and fructose) after hydrolysis. The two methods have some limitations due to the strategies used for removing background interferences (such as from sucrose, α-glucooligosaccharides, and free sugars). The method described in this paper has been developed to overcome those limitations. The method is largely based on Method 999.03 and uses combined enzymatic and SPE steps to remove the interfering components without impacting the final analytical result. The method has been validated in two laboratories on infant formula and adult nutritionals. Recoveries were in the range of 86-119%, with most being in the range of 91-104%. RSDr values were in the range of 0.7-2.6%, with one exception when the fructan concentration was close to the LOQ, resulting in an RSDr of 8.9%. The performance is generally within the requirements outlined in the AOAC Standard Method Performance Requirements (SMPR® 2014.002), which specifies recoveries in the range of 90-110% and RSDr values below 6%.


Subject(s)
Food, Formulated/analysis , Fructans/analysis , Infant Formula/analysis , Hydrolysis , Laboratories
14.
J Clin Neurosci ; 25: 157-9, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26547294

ABSTRACT

This report describes a 64-year-old woman with a strong family history of motor neuron disease, whose diagnosis of behavioural variant frontotemporal dementia was delayed due to her initial presentation with atypical manifestations, including restriction of oral intake resulting in low weight, disordered eating and anxiety. Upon investigation, she was found to be a carrier of the C9orf72 hexanucleotide repeat expansion. Our case supports previous publications asserting that C9orf72 mutation carriers manifest with diverse clinical syndromes, and expands the phenotype to include anorexia and food refusal as potential features of the condition.


Subject(s)
Amyotrophic Lateral Sclerosis/genetics , Feeding and Eating Disorders/etiology , Frontotemporal Dementia/genetics , Proteins/genetics , Amyotrophic Lateral Sclerosis/complications , C9orf72 Protein , DNA Repeat Expansion , Female , Frontotemporal Dementia/complications , Humans , Middle Aged , Phenotype
15.
J Agric Food Chem ; 63(25): 5976-84, 2015 Jul 01.
Article in English | MEDLINE | ID: mdl-26044147

ABSTRACT

Decoration of prebiotic galacto-oligosaccharides (GOS) with sialic acid yields mixtures of GOS and sialylated GOS (Sia-GOS), novel products that are expected to have both prebiotic and antiadhesive functionalities. The recombinantly produced trans-sialidase enzyme from Trypanosoma cruzi (TcTS), an enzyme with the ability to transfer (α2-3)-linked sialic acid from sialogalactoglycans to asialogalactoglycans, was employed to catalyze this sialylation. As sialic acid acceptor substrates, Vivinal GOS and derived fractions of specific degree of polymerization were taken. As sialic acid donor substrates, bovine κ-casein-derived glycomacropeptide [>99% N-acetylneuraminic acid (Neu5Ac); <1% N-glycolylneuraminic acid (Neu5Gc)] and bovine blood plasma glycoprotein mixture (45% Neu5Ac; 55% Neu5Gc) were selected, yielding potential food and feed products, respectively. High-pH anion-exchange chromatography, matrix-assisted laser-desorption ionization time-of-flight mass spectrometry, and nuclear magnetic resonance spectroscopy were used for product analysis.


Subject(s)
Caseins/chemistry , Glycoconjugates/chemistry , Glycopeptides/chemistry , Glycoproteins/chemistry , N-Acetylneuraminic Acid/chemistry , Neuraminidase/chemistry , Oligosaccharides/chemistry , Prebiotics/analysis , Protozoan Proteins/chemistry , Animals , Cattle , Color , Glycoproteins/genetics , Glycoproteins/metabolism , Molecular Structure , Neuraminidase/genetics , Neuraminidase/metabolism , Protozoan Proteins/genetics , Protozoan Proteins/metabolism , Trypanosoma cruzi/enzymology
16.
J Relig Health ; 54(3): 871-87, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25854319

ABSTRACT

We investigated the relationships between religiousness and spirituality and various indicators of mental health and positive psychosocial functioning in three separate samples of college students. A total of 898 students at Brigham Young University participated in the three studies. The students ranged in age from 17 to 26 years old, with the average age of 20.9 across all three samples. Our results indicate that intrinsic religiousness, spiritual maturity, and self-transcendence were significantly predictive of better mental health and positive functioning, including lower levels of depression, anxiety, and obsessive-compulsiveness, and higher levels of global self-esteem, identity integration, moral self-approval, and meaning in life. Intrinsic religiousness was not predictive of shame, perfectionism, and eating disorder symptoms. These findings are consistent with many prior studies that have found religiousness and spirituality to be positively associated with better mental health and positive psychosocial functioning in adolescents and young adults.


Subject(s)
Church of Jesus Christ of Latter-day Saints/psychology , Mental Health , Religion and Psychology , Adolescent , Adult , Female , Humans , Male , Self Concept , Spirituality , Students/psychology , Students/statistics & numerical data , Young Adult
17.
Carbohydr Res ; 407: 73-8, 2015 Apr 30.
Article in English | MEDLINE | ID: mdl-25723623

ABSTRACT

The abundant polymer chitin can be degraded by chitinases (EC 3.2.1.14) and ß-N-acetyl-hexosaminidases (EC 3.2.1.52) to oligosaccharides and N-acetyl-glucosamine (GlcNAc) monomers. Kinetic characterization of these enzymes requires product quantification by an assay method with a low detection limit, preferably compatible with the use of native, non-labeled substrates. Here we report a quantitative HPAEC-PAD method that allows fast separation of chitin oligosaccharides (COS) ranging from (GlcNac)1-6 at detection limits of 1-3 pmol and a linear range of 5-250 pmol. Quantification under intra- and interday precision conditions was performed with 2.1-5.4% relative standard deviation (RSD) and 1.2-10.3% RSD, respectively. This method was successfully used for the determination of the kinetic parameters of the Aspergillus niger chitinase CfcI with native COS. CfcI was recently shown to release GlcNAc from the reducing end of COS, a new activity for fungal chitinases. A Carbohydrate Binding Module of family 18 (CBM18) is inserted in the CfcI catalytic domain. Site directed mutagenesis was used to assess the functionality of this CfcI-CBM18: four of its key amino acids were replaced by glycine residues, yielding CfcISYNF. Comparison of the kinetic parameters of CfcI and CfcISYNF confirmed that this CBM18 is functionally involved in catalysis.


Subject(s)
Aspergillus niger/enzymology , Chitinases/chemistry , Chitinases/metabolism , Acetylglucosamine/metabolism , Aspergillus niger/chemistry , Aspergillus niger/genetics , Catalytic Domain , Chitin/chemistry , Chitin/isolation & purification , Chitinases/genetics , Chromatography, Ion Exchange/methods , Fungal Proteins/metabolism , Kinetics , Mutagenesis, Site-Directed , Oligosaccharides/chemistry , Oligosaccharides/isolation & purification
18.
Food Chem ; 166: 42-49, 2015 Jan 01.
Article in English | MEDLINE | ID: mdl-25053026

ABSTRACT

A strategy for the unambiguous identification and selective quantification of xanthan gum and locust bean gum (LBG) in gelled food concentrates is presented. DNA detection by polymerase chain reaction (PCR) showed to be a fast, sensitive, and selective method that can be used as a first screening tool in intact gelled food concentrates. An efficient isolation procedure is described removing components that may interfere with subsequent analyses. NMR spectroscopy enabled the direct identification of xanthan gum and the discrimination between different galactomannans in the isolated polysaccharide fraction. An enzymatic fingerprinting method using endo-ß-mannanase, in addition to being used to differentiate between galactomannans, was developed into a selective, quantitative method for LBG, whereas monosaccharide analysis was used to quantify xanthan gum. Recoveries for xanthan gum and LBG were 87% and 70%, respectively, with in-between day relative standard deviations below 20% for xanthan gum and below 10% for LBG.


Subject(s)
Galactans/chemistry , Magnetic Resonance Spectroscopy/methods , Mannans/chemistry , Plant Gums/chemistry , Polysaccharides, Bacterial/chemistry , Polysaccharides/chemistry , Polymerase Chain Reaction
19.
Appl Environ Microbiol ; 80(19): 5984-91, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25063655

ABSTRACT

trans-Sialidase (TS) enzymes catalyze the transfer of sialyl (Sia) residues from Sia(α2-3)Gal(ß1-x)-glycans (sialo-glycans) to Gal(ß1-x)-glycans (asialo-glycans). Aiming to apply this concept for the sialylation of linear and branched (Gal)nGlc oligosaccharide mixtures (GOS) using bovine κ-casein-derived glycomacropeptide (GMP) as the sialic acid donor, a kinetic study has been carried out with three components of GOS, i.e., 3'-galactosyl-lactose (ß3'-GL), 4'-galactosyl-lactose (ß4'-GL), and 6'-galactosyl-lactose (ß6'-GL). This prebiotic GOS is prepared from lactose by incubation with suitable ß-galactosidases, whereas GMP is a side-stream product of the dairy industry. The trans-sialidase from Trypanosoma cruzi (TcTS) was expressed in Escherichia coli and purified. Its temperature and pH optima were determined to be 25°C and pH 5.0, respectively. GMP [sialic acid content, 3.6% (wt/wt); N-acetylneuraminic acid (Neu5Ac), >99%; (α2-3)-linked Neu5Ac, 59%] was found to be an efficient sialyl donor, and up to 95% of the (α2-3)-linked Neu5Ac could be transferred to lactose when a 10-fold excess of this acceptor substrate was used. The products of the TcTS-catalyzed sialylation of ß3'-GL, ß4'-GL, and ß6'-GL, using GMP as the sialic acid donor, were purified, and their structures were elucidated by nuclear magnetic resonance spectroscopy. Monosialylated ß3'-GL and ß4'-GL contained Neu5Ac connected to the terminal Gal residue; however, in the case of ß6'-GL, TcTS was shown to sialylate the 3 position of both the internal and terminal Gal moieties, yielding two different monosialylated products and a disialylated structure. Kinetic analyses showed that TcTS had higher affinity for the GL substrates than lactose, while the Vmax and kcat values were higher in the case of lactose.


Subject(s)
Caseins/metabolism , Glycopeptides/metabolism , Glycoproteins/metabolism , Lactose/metabolism , Neuraminidase/metabolism , Sialic Acids/metabolism , Trypanosoma cruzi/enzymology , Animals , Biodiversity , Caseins/chemistry , Cattle , Glycopeptides/chemistry , Glycoproteins/genetics , Humans , Lactose/chemistry , Lactose/isolation & purification , Milk/chemistry , Milk/metabolism , N-Acetylneuraminic Acid/chemistry , N-Acetylneuraminic Acid/metabolism , Neuraminidase/genetics , Oligosaccharides/chemistry , Oligosaccharides/metabolism , Peptide Fragments/chemistry , Peptide Fragments/metabolism , Sialic Acids/analysis , Substrate Specificity , Trypanosoma cruzi/genetics , beta-Galactosidase/metabolism
20.
Spine (Phila Pa 1976) ; 38(4): E251-8, 2013 Feb 15.
Article in English | MEDLINE | ID: mdl-23197012

ABSTRACT

STUDY DESIGN: Retrospective study comparing cranial facet joint violation rates of open and percutaneous pedicle screws inserted using 3-dimensional image-guidance. OBJECTIVE: To determine the rate of cranial facet joint violation in intraoperative computed tomography (CT) image-guided lumbar pedicle screw instrumentation and compare facet joint violation rates between CT image-guided open and percutaneous techniques. SUMMARY OF BACKGROUND DATA: Facet joint violation by pedicle screws can potentially result in a higher rate of adjacent segment degeneration. Reported cranial facet joint violation rates range from 7% to 100%. Intraoperative image-guidance, which has enhanced pedicle screw placement accuracy, may aid in avoiding impingement of the cranial facet joints. METHODS: We reviewed 188 cases of 3-dimensional image-guided lumbar pedicle screw instrumentation from November 2006 to December 2011. The cranial screws of each construct were graded by 3 reviewers according to the Seo classification (0 = no impingement; 1 = screw head in contact/suspected to be in contact with joint; 2 = screw clearly invaded the joint) on intraoperative axial CT images. If there was a difference in evaluation, a consensus was reached to arrive at a single grade. The χ2 test was used to determine significance between the open and percutaneous group (α = 0.05). RESULTS: A total of 370 screws (245 open, 125 percutaneous) were graded. Overall facet joint violation rate was 18.9% (grade 1 = 16.2%, grade 2 = 2.7%). Open technique (grade 1 = 22.4%, grade 2 = 4.1%) had a significantly higher violation rate than percutaneous technique (grade 1 = 4%, grade 2 = 0%) (P < 0.0001). There is a trend of an increasing likelihood of facet joint violation from L1 to L5. CONCLUSION: The use of intraoperative CT image-guidance in lumbar pedicle screw placement resulted in a facet joint violation rate at the lower end of the reported range in literature. The percutaneous technique has a significantly lower facet violation rate than the open technique. LEVEL OF EVIDENCE: 4.


Subject(s)
Bone Screws , Imaging, Three-Dimensional , Lumbar Vertebrae/surgery , Radiographic Image Interpretation, Computer-Assisted , Radiography, Interventional , Spinal Fusion , Surgery, Computer-Assisted , Tomography, X-Ray Computed , Zygapophyseal Joint/surgery , Adolescent , Adult , Aged , Aged, 80 and over , Chi-Square Distribution , Child , Female , Humans , Lumbar Vertebrae/diagnostic imaging , Male , Middle Aged , Retrospective Studies , Spinal Fusion/adverse effects , Spinal Fusion/instrumentation , Spinal Fusion/methods , Surgery, Computer-Assisted/adverse effects , Treatment Outcome , Young Adult
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