Good physical function but reduced quality of life in children 3 years after ACL reconstruction.

PURPOSE: To assess children's physical function and subjective knee status 1 and 3 years after anterior cruciate ligament (ACL) reconstruction. It was hypothesised that there was no difference between the operated and normal legs in relation to physical strength and function, that there was <-2 mm side-to-side difference in knee laxity, and that the subjective knee function was better 3 years after ACL reconstruction compared to 1 year after. METHODS: Children (<16 years of age) who had an ACL reconstruction had follow-up with physical function tests (four hop tests and strength measurement in a power rig [PR]), anterior knee laxity (measured using a Rolimeter) and patient-reported outcome measures (Pedi-International Knee Documentation Committee [IKDC] and Knee injury and Osteoarthritis Outcome Score [KOOS]-Child) 1 and 3 years postoperatively. Changes from 1- to 3-year follow-up were evaluated with a paired t test. RESULTS: Out of 148 ACL reconstructed children, 60 had all measures. The four hop tests and the PR all yielded a Limb Symmetry Index >90% at both follow-ups. There was a significant improvement from 1- to 3-year follow-up in two-hop tests (6 m on time and crossover hop). Side-to-side knee laxity was >2 mm in four children at 1- and 3-year tests. Pedi-IKDC scores increased, and KOOS-Child improved significantly from 1 to 3 years in two of the five domains: 'Sport' and 'Quality of life', but scores were lower than in a cohort of normal children. CONCLUSION: The children had good objective physical function 1 and 3 years after ACL reconstruction. However, scores from the KOOS-Child sport-specific function and quality of life domains were lower than in normal children. LEVEL OF EVIDENCE: Level II.

Similar outcomes after anterior cruciate ligament reconstruction in paediatric and adult populations: a 1-year follow-up of 506 paediatric operations in Denmark.

PURPOSE: To present 1-year results after all paediatric anterior cruciate ligament (ACL) reconstructions in Denmark (5.9 M inhabitants) for the 10½ year period, 1 July 2011 to 31 December 2021. METHODS: All children who had an ACL reconstruction were enrolled. They were asked to complete Pedi-IKDC preoperatively and at 1-year follow-up. Independent observers performed pivot shift test and instrumented laxity assessment preoperatively and at 1-year follow-up. RESULTS: The median age of the 506 children (47.2% girls) was 14.3 years (9.3-15.9). The Pedi-IKDC score increased from preoperatively 61.6 ± 15.8 (mean ± SD) to 85.9 ± 13.0 at 1-year follow-up (p < 0.0001). There were concomitant injuries (to meniscus and/or cartilage) in 49.9%, but these children had preoperative and follow-up Pedi-IKDC scores similar to the scores for children with isolated injury to ACL (n. s.). Instrumented anterior laxity was 4.3 ± 1.4 (mean ± SD) mm preoperatively and 1.4 ± 1.4 mm at follow-up (p < 0.0001). Preoperatively, 3% had no pivot shift whilst this was the case for 68% postoperatively (p < 0.0001). Twenty-five children (5.6%) had 4 mm instrumented laxity or more relative to the unoperated knee at follow-up. Two patients (0.4%) had an operatively treated deep infection, three (0.5%) were operated on for reduced range of motion and two (0.4%) had a revision ACL reconstruction. CONCLUSION: ACL reconstruction resulted in a clinically meaningful increase in Pedi-IKDC, an improved instrumented stability, a reduction in the grade of pivot shift and the complication rate was low at 1-year follow-up. The risk of graft insufficiency at 1-year follow-up was the same as in an adult population. LEVEL OF EVIDENCE: II.

No correlation between performance tests, clinical measurements and data from patient-reported outcome measures (PROM) in children reconstructed for anterior cruciate ligament injury.

PURPOSE: To investigate if patient-reported outcome measures (PROMs), functional tests and clinical measures correlate well in children after reconstruction of the anterior cruciate ligament (ACL). It was hypothesized that these outcomes correlate, so it is sufficient to report only one of them. METHODS: A consecutive group of children (< 16 years old) who had an ACL reconstruction, were prospectively followed and assessed after 1-year with Pedi-IKDC and KOOS-Child, instrumented laxity measurement, range of motion, extension strength and four performance tests. Relations between the different outcomes were calculated by partial correlation coefficient analysis, controlling for gender, age, height, and weight. RESULTS: Outcomes were available for 141 of 163 children. There were only few positive and weak correlations between performance tests and PROM scores and between clinical measurements and PROM scores. There were weak to strong correlations between the scores from Pedi-IKDC and the scores from each of the five domains of KOOS-Child and a weak to moderate correlation between the different domains of KOOS-Child. Similar correlations were found between the different performance tests. CONCLUSION: For children who had their ACL reconstructed there was no clinically important correlation between scores obtained by PROMs, a battery of functional performance tests and instrumented laxity of the knee at 1-year follow-up. This is an argument for always to include and report all three types of outcomes. LEVEL OF EVIDENCE: Level II.

Novel Unspecific Peroxygenase from Truncatella angustata Catalyzes the Synthesis of Bioactive Lipid Mediators.

Lipid mediators, such as epoxidized or hydroxylated eicosanoids (EETs, HETEs) of arachidonic acid (AA), are important signaling molecules and play diverse roles at different physiological and pathophysiological levels. The EETs and HETEs formed by the cytochrome P450 enzymes are still not fully explored, but show interesting anti-inflammatory properties, which make them attractive as potential therapeutic target or even as therapeutic agents. Conventional methods of chemical synthesis require several steps and complex separation techniques and lead only to low yields. Using the newly discovered unspecific peroxygenase TanUPO from the ascomycetous fungus Truncatella angustata, 90% regioselective conversion of AA to 14,15-EET could be achieved. Selective conversion of AA to 18-HETE, 19-HETE as well as to 11,12-EET and 14,15-EET was also demonstrated with known peroxygenases, i.e., AaeUPO, CraUPO, MroUPO, MweUPO and CglUPO. The metabolites were confirmed by HPLC-ELSD, MS1 and MS2 spectrometry as well as by comparing their analytical data with authentic standards. Protein structure simulations of TanUPO provided insights into its substrate access channel and give an explanation for the selective oxyfunctionalization of AA. The present study expands the scope of UPOs as they can now be used for selective syntheses of AA metabolites that serve as reference material for diagnostics, for structure-function elucidation as well as for therapeutic and pharmacological purposes.

Broadening the Biocatalytic Toolbox-Screening and Expression of New Unspecific Peroxygenases.

Unspecific peroxygenases (UPOs) catalyze the selective transfer of single oxygen atoms from peroxides to a broad range of substrates such as un-activated hydrocarbons. Since specific oxyfunctionalizations are among the most-desired reactions in synthetic chemistry, UPOs are of high industrial interest. To broaden the number of available enzymes, computational and experimental methods were combined in this study. After a comparative alignment and homology modelling, the enzymes were expressed directly in P. pastoris. Out of ten initially selected sequences, three enzymes (one from Aspergillus niger and two from Candolleomyces aberdarensis) were actively expressed. Cultivation of respective expression clones in a bioreactor led to production titers of up to 300 mg L-1. Enzymes were purified to near homogeneity and characterized regarding their specific activities and pH-optima for typical UPO substrates. This work demonstrated that directed evolution is not necessarily required to produce UPOs in P. pastoris at respective titers. The heterologous producibility of these three UPOs will expand the toolbox of available enzymes and help to advance their synthetic application.

Peroxide-Mediated Oxygenation of Organic Compounds by Fungal Peroxygenases.

Unspecific peroxygenases (UPOs), whose sequences can be found in the genomes of thousands of filamentous fungi, many yeasts and certain fungus-like protists, are fascinating biocatalysts that transfer peroxide-borne oxygen (from H2O2 or R-OOH) with high efficiency to a wide range of organic substrates, including less or unactivated carbons and heteroatoms. A twice-proline-flanked cysteine (PCP motif) typically ligates the heme that forms the heart of the active site of UPOs and enables various types of relevant oxygenation reactions (hydroxylation, epoxidation, subsequent dealkylations, deacylation, or aromatization) together with less specific one-electron oxidations (e.g., phenoxy radical formation). In consequence, the substrate portfolio of a UPO enzyme always combines prototypical monooxygenase and peroxidase activities. Here, we briefly review nearly 20 years of peroxygenase research, considering basic mechanistic, molecular, phylogenetic, and biotechnological aspects.

First Dye-Decolorizing Peroxidase from an Ascomycetous Fungus Secreted by Xylaria grammica.

BACKGROUND: Fungal DyP-type peroxidases have so far been described exclusively for basidiomycetes. Moreover, peroxidases from ascomycetes that oxidize Mn2+ ions are yet not known. METHODS: We describe here the physicochemical, biocatalytic, and molecular characterization of a DyP-type peroxidase (DyP, EC 1.11.1.19) from an ascomycetous fungus. RESULTS: The enzyme oxidizes classic peroxidase substrates such as 2,6-DMP but also veratryl alcohol and notably Mn2+ to Mn3+ ions, suggesting a physiological function of this DyP in lignin modification. The KM value (49 µM) indicates that Mn2+ ions bind with high affinity to the XgrDyP protein but their subsequent oxidation into reactive Mn3+ proceeds with moderate efficiency compared to MnPs and VPs. Mn2+ oxidation was most effective at an acidic pH (between 4.0 and 5.0) and a hypothetical surface exposed an Mn2+ binding site comprising three acidic amino acids (two aspartates and one glutamate) could be localized within the hypothetical XgrDyP structure. The oxidation of Mn2+ ions is seemingly supported by four aromatic amino acids that mediate an electron transfer from the surface to the heme center. CONCLUSIONS: Our findings shed new light on the possible involvement of DyP-type peroxidases in lignocellulose degradation, especially by fungi that lack prototypical ligninolytic class II peroxidases.

Reference data for hop tests used in pediatric ACL injury rehabilitation: A cross-sectional study of healthy children.

In rehabilitation, four single-leg hop tests are frequently used for evaluation of ACL-injured children. However, reference values on single-leg hop performance and the corresponding limb symmetry indexes (LSIs) of healthy children younger than 15 years of age are lacking. Thus, the purpose was to describe hop performance and LSIs in healthy Danish children, and to quantify the proportion of participants passing LSI values of ≥85% as well as ≥90%. Healthy children aged 9-15 years were invited to participate in the study. Hop performance (single hop, 6-m timed hop, triple hop, and cross-over hop) was assessed for each leg for each hop test and expressed as absolute, normalized (to body height), and LSI values. Descriptive statistics were applied to calculate mean ±SD for all outcomes within age and gender groups. Further, the 95% reference interval was calculated for each age and gender group. A total of 531 healthy children (52% girls) were included in the study, representing seven age groups (9-15 years). The LSI group means across all participants for the four hop tests ranged between 84 and 95%. Between 70 and 83% of the children had an LSI of ≥85%, while 50 to 65% of the children had an LSI of ≥90%. The present reference material can be used in clinical practice when evaluating hop performance in pediatric ACL patients.

Transcriptome of different fruiting stages in the cultivated mushroom Cyclocybe aegerita suggests a complex regulation of fruiting and reveals enzymes putatively involved in fungal oxylipin biosynthesis.

BACKGROUND: Cyclocybe aegerita (syn. Agrocybe aegerita) is a commercially cultivated mushroom. Its archetypal agaric morphology and its ability to undergo its whole life cycle under laboratory conditions makes this fungus a well-suited model for studying fruiting body (basidiome, basidiocarp) development. To elucidate the so far barely understood biosynthesis of fungal volatiles, alterations in the transcriptome during different developmental stages of C. aegerita were analyzed and combined with changes in the volatile profile during its different fruiting stages. RESULTS: A transcriptomic study at seven points in time during fruiting body development of C. aegerita with seven mycelial and five fruiting body stages was conducted. Differential gene expression was observed for genes involved in fungal fruiting body formation showing interesting transcriptional patterns and correlations of these fruiting-related genes with the developmental stages. Combining transcriptome and volatilome data, enzymes putatively involved in the biosynthesis of C8 oxylipins in C. aegerita including lipoxygenases (LOXs), dioxygenases (DOXs), hydroperoxide lyases (HPLs), alcohol dehydrogenases (ADHs) and ene-reductases could be identified. Furthermore, we were able to localize the mycelium as the main source for sesquiterpenes predominant during sporulation in the headspace of C. aegerita cultures. In contrast, changes in the C8 profile detected in late stages of development are probably due to the activity of enzymes located in the fruiting bodies. CONCLUSIONS: In this study, the combination of volatilome and transcriptome data of C. aegerita revealed interesting candidates both for functional genetics-based analysis of fruiting-related genes and for prospective enzyme characterization studies to further elucidate the so far barely understood biosynthesis of fungal C8 oxylipins.

Poji: a Fiji-based tool for analysis of podosomes and associated proteins.

Podosomes are actin-based adhesion and invasion structures in a variety of cell types, with podosome-forming cells displaying up to several hundreds of these structures. Podosome number, distribution and composition can be affected by experimental treatments or during regular turnover, necessitating a tool that is able to detect even subtle differences in podosomal properties. Here, we present a Fiji-based macro code termed 'Poji' ('podosome analysis by Fiji'), which serves as an easy-to-use tool to characterize a variety of cellular and podosomal parameters, including area, fluorescence intensity, relative enrichment of associated proteins and radial podosome intensity profiles. This tool should be useful to gain more detailed insight into the regulation, architecture and functions of podosomes. Moreover, we show that Poji is easily adaptable for the analysis of invadopodia and associated extracellular matrix degradation, and likely also of other micron-size punctate structures. This article describes the workflow of the Poji macro, presents several examples of its applications, and also points out limitations, as well as respective solutions, and adaptable features to streamline the analysis.This article has an associated First Person interview with the first author of the paper.

Endoscopic fasciotomy for plantar fasciitis provides superior results when compared to a controlled non-operative treatment protocol: a randomized controlled trial.

PURPOSE: Plantar fasciitis is a frequent and painful condition with a lifetime incidence of 10%. Good results have been reported for operative treatment of plantar fasciitis refractory to non-surgical interventions in uncontrolled studies. The aim of this study was to compare the results of operative treatment (endoscopic debridement, removal of the heel spur and partial resection of the plantar fascia) with those of a controlled and supervised non-operative rehabilitation program. METHODS: Thirty consecutive patients with plantar fasciitis during more than 3 months were randomized to either (1) non-operative treatment with corticosteroid injections and a controlled strength training program or (2) an endoscopic 2-incision operation with partial fasciotomy and heel spur removal followed by the same strength training program. Patients were evaluated at entry and 3, 6, 12 and 24 months post-operatively with the foot function index (FFI) and pain score during activity on a 100 mm VAS scale (VAS activity). FFI at 6 and 12 months was defined a priori as primary endpoint. RESULTS: Both groups improved significantly over time. The FFI score was significantly better in the operated group compared to the non-surgically treated group 12 months post-operatively (p = 0.033), at 24 months this was, however, not significant (p = 0.06). VAS activity at 24 months was significantly (p = 0.001) in favor of the operative group. More patients returned to running and jumping in the operative group (p = 0.04). CONCLUSION: This randomized controlled trial found significant and clinically relevant superior results for the operative treatment of plantar fasciitis as measured by Foot Function Index at 1 year and by VAS activity at 2-year follow-up when compared to the results of a supervised rehabilitation program. LEVEL OF EVIDENCE: I.

Heterologous Production and Functional Characterization of Ageritin, a Novel Type of Ribotoxin Highly Expressed during Fruiting of the Edible Mushroom Agrocybe aegerita.

Fungi produce various defense proteins against antagonists, including ribotoxins. These toxins cleave a single phosphodiester bond within the universally conserved sarcin-ricin loop of ribosomes and inhibit protein biosynthesis. Here, we report on the structure and function of ageritin, a previously reported ribotoxin from the edible mushroom Agrocybe aegerita The amino acid sequence of ageritin was derived from cDNA isolated from the dikaryon A. aegerita AAE-3 and lacks, according to in silico prediction, a signal peptide for classical secretion, predicting a cytoplasmic localization of the protein. The calculated molecular weight of the protein is slightly higher than the one reported for native ageritin. The A. aegerita ageritin-encoding gene, AaeAGT1, is highly induced during fruiting, and toxicity assays with AaeAGT1 heterologously expressed in Escherichia coli showed a strong toxicity against Aedes aegypti larvae yet not against nematodes. The activity of recombinant A. aegerita ageritin toward rabbit ribosomes was confirmed in vitro Mutagenesis studies revealed a correlation between in vivo and in vitro activities, indicating that entomotoxicity is mediated by ribonucleolytic cleavage. The strong larvicidal activity of ageritin makes this protein a promising candidate for novel biopesticide development.IMPORTANCE Our results suggest a pronounced organismal specificity of a protein toxin with a very conserved intracellular molecular target. The molecular details of the toxin-target interaction will provide important insight into the mechanism of action of protein toxins and the ribosome. This insight might be exploited to develop novel bioinsecticides.

Plantar fasciitis treated with endoscopic partial plantar fasciotomy-One-year clinical and ultrasonographic follow-up.

BACKGROUND: Endoscopic operations for plantar fasciitis generally have good clinical outcome. The aim of this study was to record the effect of endoscopic partial fasciotomy and heel spur removal and evaluate by ultrasonography whether the fascia regenerates and the heel spur reforms. METHODS: Eleven consecutive patients were evaluated before and 3, 6 and 12 months after surgery. Operations were performed endoscopically using a deep fascial approach with a medial and a lateral portal. Bony spurs were removed and the medial half of the plantar fascia was transected. All patients followed a standardized rehabilitation program. RESULTS: Median Foot Function Index values decreased from 119 pre-surgery to 69 and 12 (p=0.004), at 3 months and 1year post-operatively respectively. Median VAS-score for first step pain was likewise reduced from median 71mm to 29mm and 7mm (p=0.004), respectively. Median fascial thickness at the medial insertion was 6.0mm (range 4.6-6.8mm) pre-operatively. A heel spur was present in 9 cases. One year postoperatively a well-defined fascia in the area of resection was demonstrated in 8 cases. In the rest of the cases scar tissue made it impossible to clearly outline the fascia. Nine of the feet showed good medial fascial tensioning. There was no evidence of recurrence of the bony spur. CONCLUSIONS: Endoscopic partial plantar fascia resection reduced pain symptoms and increased function significantly 3 months after operation, with additional effect achieved 12 months after surgery. Based on ultrasonography the resected fascia regenerated/healed, and a calcaneal spur did not recur.

Exploring molecular tools for transformation and gene expression in the cultivated edible mushroom Agrocybe aegerita.

Agrocybe aegerita is a cultivated edible mushroom in numerous countries, which also serves as a model basidiomycete to study fruiting body formation. Aiming to create an easily expandable customised molecular toolset for transformation and constitutive gene of interest expression, we first created a homologous dominant marker for transformant selection. Progeny monokaryons of the genome-sequenced dikaryon A. aegerita AAE-3 used here were identified as sensitive to the systemic fungicide carboxin. We cloned the wild-type gene encoding the iron-sulphur protein subunit of succinate dehydrogenase AaeSdi1 including its up- and downstream regions, and introduced a single-point mutation (His237 to Leu) to make it confer carboxin resistance. PEG-mediated transformation of protoplasts derived from either oidia or vegetative monokaryotic mycelium with the resulting carboxin resistance marker (CbxR) plasmid pSDI1E3 yielded carboxin-resistant transformants in both cases. Plasmid DNA linearised within the selection marker resulted in transformants with ectopic multiple insertions of plasmid DNA in a head-to-tail repeat-like fashion. When circular plasmid was used, ectopic single integration into the fungal genome was favoured, but also gene conversion at the homologous locus was seen in 1 out of 11 analysed transformants. Employing CbxR as selection marker, two versions of a reporter gene construct were assembled via Golden Gate cloning which allows easy recombination of its modules. These consisted of an eGFP expression cassette controlled by the native promoter PAaeGPDII and the heterologous terminator Tnos, once with and once without an intron in front of the eGFP start codon. After protoplast transformation with either construct as circular plasmid DNA, GFP fluorescence was detected with either transformants, indicating that expression of eGFP is intron-independent in A. aegerita. This paves the way for functional genetics approaches to A. aegerita, e.g., via constitutive expression of fruiting-related genes.

Corticosteroid injection is the best treatment in plantar fasciitis if combined with controlled training.

PURPOSE: Plantar fasciitis is a very common (lifetime incidence ~ 10%) and long-lasting injury with major impact on daily function. Combining corticosteroid injection and physical training (strength training and stretching) was hypothesized to result in a superior effect compared to each treatment separately. METHODS: A single blinded randomized controlled superiority trial conducted in 2013-2014 with a 2-year follow-up (end Sept 2016). 123 consecutive patients (20-65 years) referred to two study centers in Denmark: Institute of Sports Medicine, Bispebjerg Hospital, University of Copenhagen and a private rheumatology clinic with symptoms of plantar fasciitis, and ultrasound measured thickness above 4.0 mm were invited. 25 did not fulfill the inclusion criteria (mainly ultrasound criteria) and 8 refused participation. 90 patients were randomized (pulling sealed envelopes) to 3 groups: (1) 3 months strength training and stretching (n = 30), (2) corticosteroid injections with monthly intervals until thickness < 4.0 mm (maximum 3 injections) (n = 31), (3) combination of the two treatments (n = 29). During the 3 months intervention period load reduction was recommended (cushioning shoes and insoles and abstaining from running and jumping). The main outcome was improvement in Pain at function on a 100-mm VAS score and in Foot Function Index (FFI, range 0-230) at 6 months (Clinicaltrials.gov Identifier: NCT01994759). RESULTS: All groups improved significantly over time, but the combination of corticosteroid injection and training (strength training and stretching) had a superior effect at all time points. The mean difference between the combined treatment and training was 40 points in FFI (95% confidence interval (CI) 63-17 points, p < 0.001) and 20 mm for VAS function pain (CI 35-5 mm, p < 0.01). The mean difference between the combined treatment and corticosteroid injections only was 29 points in FFI (CI 52-7 points, p < 0.01) and 17 mm for VAS function pain (CI 32-2 mm, p < 0.05). All differences were clinically relevant. CONCLUSION: The best treatment for plantar fasciitis is the combination of corticosteroid injections and training (strength training and stretching). This combined treatment is superior both in the short- and in the longterm. Corticosteroid injections combined with controlled training are recommended as first line treatment in patients with plantar fasciitis. LEVEL OF EVIDENCE: 1.

The genome sequence of the commercially cultivated mushroom Agrocybe aegerita reveals a conserved repertoire of fruiting-related genes and a versatile suite of biopolymer-degrading enzymes.

BACKGROUND: Agrocybe aegerita is an agaricomycete fungus with typical mushroom features, which is commercially cultivated for its culinary use. In nature, it is a saprotrophic or facultative pathogenic fungus causing a white-rot of hardwood in forests of warm and mild climate. The ease of cultivation and fructification on solidified media as well as its archetypal mushroom fruit body morphology render A. aegerita a well-suited model for investigating mushroom developmental biology. RESULTS: Here, the genome of the species is reported and analysed with respect to carbohydrate active genes and genes known to play a role during fruit body formation. In terms of fruit body development, our analyses revealed a conserved repertoire of fruiting-related genes, which corresponds well to the archetypal fruit body morphology of this mushroom. For some genes involved in fruit body formation, paralogisation was observed, but not all fruit body maturation-associated genes known from other agaricomycetes seem to be conserved in the genome sequence of A. aegerita. In terms of lytic enzymes, our analyses suggest a versatile arsenal of biopolymer-degrading enzymes that likely account for the flexible life style of this species. Regarding the amount of genes encoding CAZymes relevant for lignin degradation, A. aegerita shows more similarity to white-rot fungi than to litter decomposers, including 18 genes coding for unspecific peroxygenases and three dye-decolourising peroxidase genes expanding its lignocellulolytic machinery. CONCLUSIONS: The genome resource will be useful for developing strategies towards genetic manipulation of A. aegerita, which will subsequently allow functional genetics approaches to elucidate fundamentals of fruiting and vegetative growth including lignocellulolysis.

If these walls could talk: utilizing health data from the home to reduce unnecessary readmissions.

In the post-Affordable Care Act landscape (ACA), comprehensive care management has become an essential component in the universal goal to reduce hospital readmissions and their associated costs. Utilizing real-time home health monitoring technologies, hospitals can transform transitional care from hospital to home while significantly improving long-term home care outcomes. To achieve the Institute for Healthcare Improvement's Triple Aim, we need widespread commitment and investment in home healthcare IT that connects clinicians, providers, and payers to patients with speed and accuracy. Technology that generates real-time actionable health care data from the home is an essential key to progress in this endeavor.

Semantics-enabled service discovery framework in the SIMDAT pharma grid.

We present the design and implementation of a semantics-enabled service discovery framework in the data Grids for process and product development using numerical simulation and knowledge discovery (SIMDAT) Pharma Grid, an industry-oriented Grid environment for integrating thousands of Grid-enabled biological data services and analysis services. The framework consists of three major components: the Web ontology language (OWL)-description logic (DL)-based biological domain ontology, OWL Web service ontology (OWL-S)-based service annotation, and semantic matchmaker based on the ontology reasoning. Built upon the framework, workflow technologies are extensively exploited in the SIMDAT to assist biologists in (semi)automatically performing in silico experiments. We present a typical usage scenario through the case study of a biological workflow: IXodus.