Cadence Detection in Road Cycling Using Saddle Tube Motion and Machine Learning.

Most commercial cadence-measurement systems in road cycling are strictly limited in their function to the measurement of cadence. Other relevant signals, such as roll angle, inclination or a round kick evaluation, cannot be measured with them. This work proposes an alternative cadence-measurement system with less of the mentioned restrictions, without the need for distinct cadence-measurement apparatus attached to the pedal and shaft of the road bicycle. The proposed design applies an inertial measurement unit (IMU) to the seating pole of the bike. In an experiment, the motion data were gathered. A total of four different road cyclists participated in this study to collect different datasets for neural network training and evaluation. In total, over 10 h of road cycling data were recorded and used to train the neural network. The network's aim was to detect each revolution of the crank within the data. The evaluation of the data has shown that using pure accelerometer data from all three axes led to the best result in combination with the proposed network architecture. A working proof of concept was achieved with an accuracy of approximately 95% on test data. As the proof of concept can also be seen as a new method for measuring cadence, the method was compared with the ground truth. Comparing the ground truth and the predicted cadence, it can be stated that for the relevant range of 50 rpm and above, the prediction over-predicts the cadence with approximately 0.9 rpm with a standard deviation of 2.05 rpm. The results indicate that the proposed design is fully functioning and can be seen as an alternative method to detect the cadence of a road cyclist.

Enzymatic synthesis and formation kinetics of mono- and di-hydroxylated chlorinated paraffins with the bacterial dehalogenase LinB from Sphingobium indicum.

Transformation studies of chlorinated paraffins (CPs) and the effects of CP transformation products on humans, biota and environment are rare. The focus here is on hydroxylation reactions. As for polyhalogenated persistent organic pollutants (POPs) in general, hydroxylation reactions convert lipophilic material to more polar compounds with increased mobility. We investigated the in-vitro transformation of single-chain CP-mixtures to hydroxylated products with the dehalogenase LinB from Sphingobium indicum. C11-, C12- and C13-single-chain CP-homologues were exposed to LinB and mono-hydroxylated (CP-ols) and di-hydroxylated (CP-diols) transformation products were formed. Liquid-chromatography coupled to mass-spectrometry (LC-MS) was used to detect hydroxylated products and to separate them from the starting material. The presented data can be used to identify these CP-ol and CP-diol homologues in other samples. Hydroxylated products had lower chlorination degrees (nCl) than respective CP-starting-materials. Reactive and persistent CP-material was found in each homologue group. Reactive material is converted within hours by LinB, while more persistent CPs are transformed within days. Homologue-specific kinetic models were established to simulate the stepwise hydroxylation of persistent CPs to mono- and di-hydroxylated products. First-order rate constants for the formation of CP-ols (k1) and CP-diols (k2) were deduced for different homologues. Lower-chlorinated CP-ols did not accumulate to large extent and were transformed quickly to CP-diols, while higher-chlorinated CP-ols and -diols both accumulated. By enzymatic transformation of single-chain CPs with LinB, we synthesized unique sets of mono- and di-hydroxylated materials, which can be used as analytical standards and as starting materials for metabolic, toxicity and environmental fate studies.

Transformation of ε-HBCD with the Sphingobium Indicum enzymes LinA1, LinA2 and LinATM, a triple mutant of LinA2.

Hexabromocyclododecanes (HBCDs) were used as flame-retardants until their ban in 2013. Among the 16 stereoisomers known, ε-HBCD has the highest symmetry. This makes ε-HBCD an interesting substrate to study the selectivity of biotransformations. We expressed three LinA dehydrohalogenase enzymes in E. coli bacteria, two wild-type, originating from Sphingobium indicum B90A bacteria and LinATM, a triple mutant of LinA2, with mutations of L96C, F113Y and T133 M. These enzymes are involved in the hexachlorocyclohexane (HCH) metabolism, specifically of the insecticide γ-HCH (Lindane). We studied the reactivity of those eight HBCD stereoisomers found in technical HBCD. Furthermore, we compared kinetics and selectivity of these LinA variants with respect to ε-HBCD. LC-MS data indicate that all enzymes converted ε-HBCD to pentabromocyclododecenes (PBCDens). Transformations followed Michaelis-Menten kinetics. Rate constants kcat and enzyme specificities kcat/KM indicate that ε-HBCD conversion was fastest and most specific with LinA2. Only one PBCDen stereoisomer was formed by LinA2, while LinA1 and LinATM produced mixtures of two PBCDE enantiomers at three times lower rates than LinA2. In analogy to the biotransformation of (-)ß-HBCD, with selective conversion of dibromides in R-S-configuration, we assume that 1E,5S,6R,9S,10R-PBCDen is the ε-HBCD transformation product from LinA2. Implementing three amino acids of the LinA1 substrate-binding site into LinA2 resulted in a triple mutant with similar kinetics and product specificity like LinA1. Thus, point-directed mutagenesis is an interesting tool to modify the substrate- and product-specificity of LinA enzymes and enlarge their scope to metabolize other halogenated persistent organic pollutants regulated under the Stockholm Convention.

German critical incident reporting system database of prehospital emergency medicine: Analysis of reported communication and medication errors between 2005-2015.

BACKGROUND: Communication failure in prehospital emergency medicine can affect patient safety as it does in other areas of medicine as well. We analyzed the database of the critical incident reporting system for prehospital emergency medicine in Germany retrospectively regarding communication errors. METHODS: Experts of prehospital emergency medicine and risk management screened the database for verbal communication failure, non-verbal communication failure and missing communication at all. RESULTS: Between 2005 and 2015, 845 reports were analyzed, of which 247 reports were considered to be related to communication failure. An arbitrary classification resulted in six different kinds: 1) no acknowledgement of a suggestion; 2) medication error; 3) miscommunication with dispatcher; 4) utterance heard/understood improperly; 5) missing information transfer between two persons; and 6) other communication failure. CONCLUSION: Communication deficits can lead to critical incidents in prehospital emergency medicine and are a very important aspect in patient safety.

[Emergency Department Interfaces]. / Schnittstelle Zentrale Notaufnahme.

Emergency Departments ED may be an exceptionally good example of an interface within a hospital. EDs have no patients of their own but pass them over to other institutions, either to specialist departments within the hospital or to primary care providers. Moreover, many doctors, nurses, attendants and institutions take part in the care of emergency department patients, and thus the number of its interfaces is very high. The characteristics of working in an ED, for example shortage of time, high work load, taking care of several patients at the same time and frequently crowding, may compromise the transfer of information via interfaces, sometimes including even vital data. The best way to secure handoff of information may be the formalization and standardization of this process, assuring patient safety and quality of care. Further study is required.

German critical incident reporting system database of prehospital emergency medicine: Analysis of reported communication and medication errors between 2005–2015 / 世界急诊医学杂志（英文）

@#BACKGROUND: Communication failure in prehospital emergency medicine can affect patient safety as it does in other areas of medicine as well. We analyzed the database of the critical incident reporting system for prehospital emergency medicine in Germany retrospectively regarding communication errors. METHODS: Experts of prehospital emergency medicine and risk management screened the database for verbal communication failure, non-verbal communication failure and missing communication at all. RESULTS: Between 2005 and 2015, 845 reports were analyzed, of which 247 reports were considered to be related to communication failure. An arbitrary classification resulted in six different kinds: 1) no acknowledgement of a suggestion; 2) medication error; 3) miscommunication with dispatcher; 4) utterance heard/understood improperly; 5) missing information transfer between two persons; and 6) other communication failure. CONCLUSION: Communication deficits can lead to critical incidents in prehospital emergency medicine and are a very important aspect in patient safety.

Stereochemistry of enzymatic transformations of (+)ß- and (-)ß-HBCD with LinA2--a HCH-degrading bacterial enzyme of Sphingobium indicum B90A.

LinA2, a bacterial enzyme expressed in various Sphingomonadaceae, catalyzes the elimination of HCl from hexachlorocyclohexanes (HCHs) and, as discussed here, the release of HBr from certain hexabromocyclododecanes (HBCDs). Both classes of compounds are persistent organic pollutants now regulated under the Stockholm Convention. LinA2 selectively catalyzes the transformation of ß-HBCDs; other stereoisomers like α-, γ-, and δ-HBCDs are not converted. The transformation of (-)ß-HBCD is considerably faster than that of its enantiomer. Here, we present the XRD crystal structure of 1E,5S,6S,9R,10S-pentabromocyclododecene (PBCDE) and demonstrate that its enantiomer with the 1E,5R,6R,9S,10R-configuration is the only metabolite formed during LinA2-catalyzed dehydrobromination of (-)ß-HBCD. Formation of this product can be rationalized by HBr elimination at C5 and C6. A reasonable enzyme-substrate complex with the catalytic dyad His-73 and Asp-25 approaching the hydrogen at C6 and a cationic pocket of Lys-20, Try-42 and Arg-129 binding the leaving bromine at C5 was found from in silico docking experiments. A second PBCDE of yet unknown configuration was obtained from (+)ß-HBCD. We predicted its stereochemistry to be 1E,5S,6S,9S,10R-PBCDE from docking experiments. The enzyme-substrate complex obtained from LinA2 and an activated conformation of (+)ß-HBCD allows the HBr elimination at C9 and C10 leading to the predicted product. Both modeled enzyme-substrate complexes are in line with 1,2-diaxial HBr eliminations. In conclusion, LinA2, a bacterial enzyme of the HCH-degrading strain Sphingobium indicum B90A was able to stereoselectively convert ß-HBCDs. Configurations of both PBCDE metabolites were predicted by molecular docking experiments and confirmed in one case by XRD data.

Development of methods for the bioanalysis of RRx-001 and metabolites.

BACKGROUND: Bioanalytical methods were required to study the novel anticancer drug, RRx-001 preclinically and for clinical pharmacokinetic analysis; however, RRx-001 quickly and completely disappeared on intravenous administration in preclinical species. RESULTS: Quantification of RRx-001 directly or by derivatization was unsuccessful. On exposure to whole blood, RRx-001 formed the glutathione (GSH) adduct very rapidly, suggesting this metabolite as the bioanalyte. However, rapid enzymatic degradation in the blood matrix of RRx-001-GSH posed significant technical problems. Herein, we describe a novel and broadly applicable solution to stabilize GSH conjugates in blood samples by inhibiting the degrading enzyme. Liquid chromatography-tandem mass spectrometry methods for analysis of RRx-001-GSH in rat, dog and human plasma were developed and successfully validated to good laboratory practice standards. CONCLUSION: Extensive breakdown of RRx-001-GSH was effectively stopped by addition of the enzyme inhibitor, acivicin. The developed liquid chromatography-tandem mass spectrometry assay for RRx-001-GSH was validated for use in preclinical toxicology studies and the Phase I first-in-human clinical trial.

LinA2, a HCH-converting bacterial enzyme that dehydrohalogenates HBCDs.

Hexabromocyclododecanes (HBCDs) and hexachlorocyclohexanes (HCHs) are lipophilic, polyhalogenated hydrocarbons with comparable stereochemistry. Bacterial evolution in HCH-contaminated soils resulted in the development of several Spingomonadaceae which express a series of HCH-converting enzymes. We showed that LinB, a haloalkane dehalogenase from Sphingobium indicum B90A, also transforms various HBCDs besides HCHs. Here we present evidence that LinA2, another dehalogenase from S. indicum also converts certain HBCDs to pentabromocyclododecenes (PBCDEs). Racemic mixtures of α-, ß-, γ-HBCDs, a mixture of them, and δ-HBCD, a meso form, were exposed to LinA2. Substantial conversion of (-)ß-HBCD was observed, but all other stereoisomers were not transformed significantly. The enantiomeric excess (EE) of ß-HBCDs increased up to 60% in 32 h, whereas EE values of α- and γ-HBCDs were not affected. Substrate conversion and product formation were described with second-order kinetic models. One major (P1ß) and possibly two minor (P2ß, P3ß) metabolites were detected. Respective mass spectra showed the characteristic isotope pattern of PBCDEs, the HBr elimination products of HBCDs. Michaelis-Menten parameters KM=0.47 ± 0.07 µM and vmax=0.17 ± 0.01 µmoll(-1)h(-1) were deduced from exposure data with varying enzyme/substrate ratios. LinA2 is more substrate specific than LinB, the latter converted all tested HBCDs, LinA2 only one. The widespread HCH pollution favored the selection and evolution of bacteria converting these compounds. We found that LinA2 and LinB, two of these HCH-converting enzymes expressed in S. indicum B90A, also dehalogenate HBCDs to lower brominated compounds, indicating that structural similarities of both classes of compounds are recognized at the level of substrate-protein interactions.

Critical incident reporting in emergency medicine: results of the prehospital reports.

BACKGROUND: Medical errors frequently contribute to morbidity and mortality. Prehospital emergency medicine is prone to incidents that can lead to immediate deadly consequences. Critical incident reporting can identify typical problems and be the basis for structured risk management in order to reduce and mitigate these incidents. METHODS: We set up a free access internet website for German-speaking countries, with an anonymous reporting system for emergency medical services personnel. After a 7-year study period, an expert team analysed and classified the incidents into staff related, equipment related, organisation and tactics, or other. RESULTS: 845 reports were entered in the study period. Physicians reported 44% of incidents, paramedics 42%. Most patients were in a life-threatening or potentially life-threatening situation (82%), and only 53% of all incidents had no influence on the outcome of the patient. Staff-related problems were responsible for 56% of the incidents, when it came to harm, 78% of these incidents were staff related. CONCLUSIONS: Incident reporting in prehospital emergency medicine can identify system weaknesses. Most of the incidents were reported during care of patients in life-threatening conditions with a high impact on patient outcome. Staff-related problems contributed to the most frequent and most severe incidents.

Metabolomics of hexachlorocyclohexane (HCH) transformation: ratio of LinA to LinB determines metabolic fate of HCH isomers.

Although the production and use of technical hexachlorocyclohexane (HCH) and lindane (the purified insecticidal isomer γ-HCH) are prohibited in most countries, residual concentrations still constitute an immense environmental burden. Many studies describe the mineralization of γ-HCH by bacterial strains under aerobic conditions. However, the metabolic fate of the other HCH isomers is not well known. In this study, we investigated the transformation of α-, ß-, γ-, δ-, ε-HCH, and a heptachlorocyclohexane isomer in the presence of varying ratios of the two enzymes that initiate γ-HCH degradation, a dehydrochlorinase (LinA) and a haloalkane dehalogenase (LinB). Each substrate yielded a unique metabolic profile that was strongly dependent on the enzyme ratio. Comparison of these results to those of in vivo experiments with different bacterial isolates showed that HCH transformation in the tested strains was highly optimized towards productive metabolism of γ-HCH and that under these conditions other HCH-isomers were metabolized to mixtures of dehydrochlorinated and hydroxylated side-products. In view of these results, bioremediation efforts need very careful planning and toxicities of accumulating metabolites need to be evaluated.

Lack of the endosomal SNAREs vti1a and vti1b led to significant impairments in neuronal development.

Fusion between membranes is mediated by specific SNARE complexes. Here we report that fibroblasts survive the absence of the trans-Golgi network/early endosomal SNARE vti1a and the late endosomal SNARE vti1b with intact organelle morphology and minor trafficking defects. Because vti1a and vti1b are the only members of their SNARE subclass and the yeast homolog Vti1p is essential for cell survival, these data suggest that more distantly related SNAREs acquired the ability to function in endosomal traffic during evolution. However, absence of vti1a and vti1b resulted in perinatal lethality. Major axon tracts were missing, reduced in size, or misrouted in Vti1a(-/-) Vti1b(-/-) embryos. Progressive neurodegeneration was observed in most Vti1a(-/-) Vti1b(-/-) peripheral ganglia. Neurons were reduced by more than 95% in Vti1a(-/-) Vti1b(-/-) dorsal root and geniculate ganglia at embryonic day 18.5. These data suggest that special demands for endosomal membrane traffic could not be met in Vti1a(-/-) Vti1b(-/-) neurons. Vti1a(-/-) and Vti1b(-/-) single deficient mice were viable without these neuronal defects, indicating that they can substitute for each other in these processes.

Critical incidents during prehospital cardiopulmonary resuscitation: what are the problems nobody wants to talk about?

We wanted to identify incidents that led or could have led to patient harm during prehospital cardiopulmonary resuscitation. A nationwide anonymous and Internet-based critical incident reporting system gave the data. During a 4-year period we received 548 reports of which 74 occurred during cardiopulmonary resuscitation. Human error was responsible for 85% of the incidents, whereas equipment failure contributed to 15% of the reports. Equipment failure was considered to be preventable in 61% of all the cases, whereas incidents because of human error could have been prevented in almost all the cases. In most cases, prevention can be accomplished by simple strategies with the Poka-Yoke technique. Insufficient training of emergency medical service physicians in Germany requires special attention. The critical incident reports raise concerns regarding the level of expertize provided by emergency medical service doctors.

The missing link in linear alkylbenzenesulfonate surfactant degradation: 4-sulfoacetophenone as a transient intermediate in the degradation of 3-(4-sulfophenyl)butyrate by Comamonas testosteroni KF-1.

Biodegradation of the laundry surfactant linear alkylbenzenesulfonate (LAS) involves complex bacterial communities. The known heterotrophic community has two tiers. First, all LAS congeners are oxygenated and oxidized to about 50 sulfophenylcarboxylates (SPC). Second, the SPCs are mineralized. Comamonas testosteroni KF-1 mineralizes 3-(4-sulfophenyl)butyrate (3-C4-SPC). During growth of strain KF-1 with 3-C4-SPC, two transient intermediates were detected in the culture medium. One intermediate was identified as 4-sulfoacetophenone (SAP) (4-acetylbenzenesulfonate) by nuclear magnetic resonance (NMR). The other was 4-sulfophenol (SP). This information allowed us to postulate a degradation pathway that comprises the removal of an acetyl moiety from (derivatized) 3-C4-SPC, followed by a Baeyer-Villiger monooxygenation of SAP and subsequent ester cleavage to yield SP. Inducible NADPH-dependent SAP-oxygenase was detected in crude extracts of strain KF-1. The enzyme reaction involved transient formation of 4-sulfophenol acetate (SPAc), which was completely hydrolyzed to SP and acetate. SP was subject to NADH-dependent oxygenation in crude extract, and 4-sulfocatechol (SC) was subject to oxygenolytic ring cleavage. The first complete degradative pathway for an SPC can now be depicted with 3-C4-SPC: transport, ligation to a coenzyme A (CoA) ester, and manipulation to allow abstraction of acetyl-CoA to yield SAP, Baeyer-Villiger monooxygenation to SPAc, hydrolysis of the ester to acetate and SP, monooxygenation of SP to SC, the ortho ring-cleavage pathway with desulfonation, and sulfite oxidation.

Emergency medicine in modern Europe.

Emergency medicine in the highly advanced world is traditionally performed in two different ways. The first is the well-known Anglo-American system with skilled EDs, and a pre-hospital emergency medical service utilizing paramedics. The second is the so-called Franco-German system, with a highly developed pre-hospital emergency physician service, but only a basic organization of hospital-based emergency medicine. This gap is now closing fast because of the rapid advancement of hospital-based emergency medicine in Europe. Four criteria might be used to measure this: the recognition as a specialty, the specialist training programme, the professional organization of emergency physicians and the presence of academic centres in Europe. Eleven of the 27 European countries recognize hospital-based emergency medicine as a specialty already. These include Belgium, Czech Republic, Estonia, Hungary, Ireland, Italy, Malta, Poland, Romania, Slovenia and the United Kingdom. Other nations are striving to do so, for example Sweden, France, Germany and Greece. There is no doubt that emergency medicine is gaining momentum and other countries will follow. Training for the specialty of emergency medicine is advanced already. Several curricula presently exist in the respective European countries. A task force, governed by the European Society for Emergency Medicine has been working hard to create a model curriculum for all of Europe, which is expected to be published in 2007. This comprises a 5-year specialty training, with three of them spent in an ED. The curriculum follows a symptom-oriented approach to emergency medicine, and includes a skilled description of the key competencies of the future trained emergency physicians. Given the century-long history of the pre-hospital emergency physician service in some European countries, a number of professional bodies exist representing pre-hospital emergency doctors. Within the last few years, ED physicians followed suit forming organizations of their own. In some countries, the next step of amalgamation has occurred, with the merger of EMS and ED emergency physician organizations, although no country has abolished the pre-hospital emergency physician service. The last milestone, the development of academic emergency centres, has only just started. This process will take some time. The present paper describes the present and future of emergency medicine in some European countries using these criteria.

Description of Sphingosinicella xenopeptidilytica sp. nov., a beta-peptide-degrading species, and emended descriptions of the genus Sphingosinicella and the species Sphingosinicella microcystinivorans.

A Gram-negative, rod-shaped bacterium, strain 3-2W4(T), was isolated from the aeration tank of a wastewater treatment plant in Zurich and was found to have the exceptional capacity to degrade synthetic beta-peptides. 16S rRNA gene sequence analysis showed that strain 3-2W4(T) is closely related to Sphingosinicella microcystinivorans Y2(T), but DNA-DNA hybridization experiments between these two strains revealed that they belong to two different species. The two strains displayed different fingerprints after PCR analysis using the repetitive primers BOX, ERIC and REP. Strain 3-2W4(T) did not degrade microcystin, which is a characteristic trait of Sphingosinicella microcystinivorans Y2(T). Like Sphingosinicella microcystinivorans Y2(T), strain 3-2W4(T) had the following characteristics: fatty acids comprising mainly C(18 : 1)omega7c, summed feature 3 (C(16 : 1)omega7c and/or iso-C(15 : 0) 2-OH) and C(16 : 0), the presence of ubiquinone Q-10 and sym-homospermidine as the predominant polyamine compound. The polar lipid profiles of the two strains were almost identical, consisting of phosphatidylethanolamine, phosphatidylmonomethylethanolamine, phosphatidylglycerol and sphingoglycolipid. Strain 3-2W4(T) and Sphingosinicella microcystinivorans Y2(T) utilized the beta-peptides H-betahVal-betahAla-betahLeu-OH and H-betahAla-betahLeu-OH as sole carbon and energy sources and shared beta-peptidyl aminopeptidase activity in common, which distinguishes them from Sphingomonas and Sphingopyxis type strains. On the basis of these results, strain 3-2W4(T) represents a novel species of the genus Sphingosinicella, for which the name Sphingosinicella xenopeptidilytica sp. nov. is proposed. The type strain is 3-2W4(T) (=DSM 17130(T)=CCUG 52537(T)). The descriptions of the genus Sphingosinicella and the species Sphingosinicella microcystinivorans are emended.

Purification and characterization of two enantioselective alpha-ketoglutarate-dependent dioxygenases, RdpA and SdpA, from Sphingomonas herbicidovorans MH.

Alpha-ketoglutarate-dependent (R)-dichlorprop dioxygenase (RdpA) and alpha-ketoglutarate-dependent (S)-dichlorprop dioxygenase (SdpA), which are involved in the degradation of phenoxyalkanoic acid herbicides in Sphingomonas herbicidovorans MH, were expressed and purified as His6-tagged fusion proteins from Escherichia coli BL21(DE3)(pLysS). RdpA and SdpA belong to subgroup II of the alpha-ketoglutarate-dependent dioxygenases and share the specific motif HXDX(24)TX(131)HX(10)R. Amino acids His-111, Asp-113, and His-270 and amino acids His-102, Asp-104, and His 257 comprise the 2-His-1-carboxylate facial triads and were predicted to be involved in iron binding in RdpA and SdpA, respectively. RdpA exclusively transformed the (R) enantiomers of mecoprop [2-(4-chloro-2-methylphenoxy)propanoic acid] and dichlorprop [2-(2,4-dichlorophenoxy)propanoic acid], whereas SdpA was specific for the (S) enantiomers. The apparent Km values were 99 microM for (R)-mecoprop, 164 microM for (R)-dichlorprop, and 3 microM for alpha-ketoglutarate for RdpA and 132 microM for (S)-mecoprop, 495 microM for (S)-dichlorprop, and 20 microM for alpha-ketoglutarate for SdpA. Both enzymes had high apparent Km values for oxygen; these values were 159 microM for SdpA and >230 microM for RdpA, whose activity was linearly dependent on oxygen at the concentration range measured. Both enzymes had narrow cosubstrate specificity; only 2-oxoadipate was able to replace alpha-ketoglutarate, and the rates were substantially diminished. Ferrous iron was necessary for activity of the enzymes, and other divalent cations could not replace it. Although the results of growth experiments suggest that strain MH harbors a specific 2,4-dichlorophenoxyacetic acid-converting enzyme, tfdA-, tfdAalpha-, or cadAB-like genes were not discovered in a screening analysis in which heterologous hybridization and PCR were used.

Anaerobic transformation of 2,4,6-TNT by bovine ruminal microbes.

Degradation of TNT by bovine rumen fluid, a novel source of anaerobic microbes, was investigated. Whole rumen fluid contents were spiked with TNT and incubated for a 24h time period. Supernatant samples taken at 0, 1, 2, 4, and 24h were analyzed by reverse-phase HPLC with diode array detection. Within 1h, TNT was not detectable and reduction products of TNT including 2-hydroxyl-amino-4,6-dinitrotoluene, 4-hydroxylamino-2,6-dinitrotoluene, and 4-amino-2,6-dinitrotoluene were present with smaller amounts of diamino-nitrotoluenes. Within 2h, only the diamino and dihydroxyamino-nitrotoluene products remained. After 4h, 2,4-diamino-6-nitrotoluene and 2,4-dihydroxyamino-6-nitrotoluene were the only known molecular species left. At 24h known UV absorbing metabolites were no longer detected, suggesting further transformation such as complete reduction to triaminotoluene or destruction of the aromatic ring of TNT may have occurred. TNT was not transformed at 24h in autoclaved and buffered controls. This study presents the first direct evidence of biodegradation of TNT by ruminal microbes.