Surveillance and detection of Haemaphysalis longicornis (Acari: Ixodidae) in protected areas from Georgia, USA.

The invasion of the Asian longhorned tick, Haemaphysalis longicornis Neumann, into the United States poses a significant ecological, veterinarian, and public health threat. We conducted a comprehensive tick survey using standard tick flagging protocol for collection over 3 field seasons, March-August, and 56 surveyed sites to identify the presence of H. longicornis in the native ecosystem and prove its establishment according to USDA criteria. Of the total 56 state parks and wildlife management areas (WMA) surveyed, only one was found to be invaded by H. longicornis; detection of H. longicornis occurred at Buck Shoals Wildlife Management area in White County, GA. This site is maintained by the state of Georgia, has no agricultural animals present, and hosts a large white-tailed deer population. After the initial detection of H. longicornis in 2022, an additional field season occurred in 2023, where H. longicornis was confirmed as established based on USDA criteria. The increase in H. longicornis populations from 2021 to 2023 at Buck Shoals WMA points to the rapid spread of this tick within the environment. Our findings provide evidence of the rapid establishment of H. longicornis in the southern edge of suitability for this tick and within the native ecosystem beyond farmlands and private land.

Sequence similarity network analysis of drug- and dye-modifying azoreductase enzymes found in the human gut microbiome.

Drug metabolism by human gut microbes is often exemplified by azo bond reduction in the anticolitic prodrug sulfasalazine. Azoreductase activity is often found in incubations with cell cultures or ex vivo gut microbiome samples and contributes to the xenobiotic metabolism of drugs and food additives. Applying metagenomic studies to personalized medicine requires knowledge of the genes responsible for sulfasalazine and other drug metabolism, and candidate genes and proteins for drug modifications are understudied. A representative gut-abundant azoreductase from Anaerotignum lactatifermentan DSM 14214 efficiently reduces sulfasalazine and another drug, phenazopyridine, but could not reduce all azo-bonded drugs in this class. We used enzyme kinetics to characterize this enzyme for its NADH-dependent reduction of these drugs and food additives and performed computational docking to provide the groundwork for understanding substrate specificity in this family. We performed an analysis of the Flavodoxin-like fold InterPro family (IPR003680) by computing a sequence similarity network to classify distinct subgroups of the family and then performed chemically-guided functional profiling to identify proteins that are abundant in the NIH Human Microbiome Project dataset. This strategy aims to reduce the number of unique azoreductases needed to characterize one protein family in the diverse set of potential drug- and dye-modifying activities found in the human gut microbiome.

Mapping the distribution of Amblyomma americanum in Georgia, USA.

BACKGROUND: Amblyomma americanum, the lone star tick, is an aggressive questing species that harbors several pathogens dangerous to humans in the United States. The Southeast in particular has large numbers of this tick due to the combined suitable climate and habitats throughout the region. No studies have estimated the underlying distribution of the lone star tick across the state of Georgia, a state where it is the dominant species encountered. METHODS: Ticks were collected by flagging 198 transects of 750 m2 at 43 state parks and wildlife management areas across the state from March to July of 2022. A suite of climate, landscape, and wildlife variables were assembled, and a logistic regression model was used to assess the association between these environmental factors and the presence of lone star ticks and to predict the distribution of these ticks across the state. RESULTS: A total of 59/198 (30%) transects sampled contained adult or nymph A. americanum, with the majority of transects containing these ticks (54/59, 91.5%) in forested habitats. The presence of A. americanum was associated with elevation, normalized difference vegetation index (NDVI) on January 1, isothermality, temperature seasonality, and precipitation in the wettest quarter. Vast regions of central, eastern, and southern coastal Georgia (57% of the state) were categorized as suitable habitat for the lone star tick. CONCLUSIONS: This study describes the distribution of the lone star tick across the state of Georgia at a finer scale than the current county-level information available. It identifies specific variables associated with tick presence and provides a map that can be used to target areas for tick prevention messaging and awareness.

Comparison of Nanotrap® Microbiome A Particles, membrane filtration, and skim milk workflows for SARS-CoV-2 concentration in wastewater.

Introduction: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) RNA monitoring in wastewater has become an important tool for Coronavirus Disease 2019 (COVID-19) surveillance. Grab (quantitative) and passive samples (qualitative) are two distinct wastewater sampling methods. Although many viral concentration methods such as the usage of membrane filtration and skim milk are reported, these methods generally require large volumes of wastewater, expensive lab equipment, and laborious processes. Methods: The objectives of this study were to compare two workflows (Nanotrap® Microbiome A Particles coupled with MagMax kit and membrane filtration workflows coupled with RNeasy kit) for SARS-CoV-2 recovery in grab samples and two workflows (Nanotrap® Microbiome A Particles and skim milk workflows coupled with MagMax kit) for SARS-CoV-2 recovery in Moore swab samples. The Nanotrap particle workflow was initially evaluated with and without the addition of the enhancement reagent 1 (ER1) in 10 mL wastewater. RT-qPCR targeting the nucleocapsid protein was used for detecting SARS-CoV-2 RNA. Results: Adding ER1 to wastewater prior to viral concentration significantly improved viral concentration results (P < 0.0001) in 10 mL grab and swab samples processed by automated or manual Nanotrap workflows. SARS-CoV-2 concentrations in 10 mL grab and Moore swab samples with ER1 processed by the automated workflow as a whole showed significantly higher (P < 0.001) results than 150 mL grab samples using the membrane filtration workflow and 250 mL swab samples using the skim milk workflow, respectively. Spiking known genome copies (GC) of inactivated SARS-CoV-2 into 10 mL wastewater indicated that the limit of detection of the automated Nanotrap workflow was ~11.5 GC/mL using the RT-qPCR and 115 GC/mL using the digital PCR methods. Discussion: These results suggest that Nanotrap workflows could substitute the traditional membrane filtration and skim milk workflows for viral concentration without compromising the assay sensitivity. The manual workflow can be used in resource-limited areas, and the automated workflow is appropriate for large-scale COVID-19 wastewater-based surveillance.

Exercise treatment effect modifiers in persistent low back pain: an individual participant data meta-analysis of 3514 participants from 27 randomised controlled trials.

BACKGROUND: Low back pain is one of the leading causes of disability worldwide. Exercise therapy is widely recommended to treat persistent non-specific low back pain. While evidence suggests exercise is, on average, moderately effective, there remains uncertainty about which individuals might benefit the most from exercise. METHODS: In parallel with a Cochrane review update, we requested individual participant data (IPD) from high-quality randomised clinical trials of adults with our two primary outcomes of interest, pain and functional limitations, and calculated global recovery. We compiled a master data set including baseline participant characteristics, exercise and comparison characteristics, and outcomes at short-term, moderate-term and long-term follow-up. We conducted descriptive analyses and one-stage IPD meta-analysis using multilevel mixed-effects regression of the overall treatment effect and prespecified potential treatment effect modifiers. RESULTS: We received IPD for 27 trials (3514 participants). For studies included in this analysis, compared with no treatment/usual care, exercise therapy on average reduced pain (mean effect/100 (95% CI) -10.7 (-14.1 to -7.4)), a result compatible with a clinically important 20% smallest worthwhile effect. Exercise therapy reduced functional limitations with a clinically important 23% improvement (mean effect/100 (95% CI) -10.2 (-13.2 to -7.3)) at short-term follow-up. Not having heavy physical demands at work and medication use for low back pain were potential treatment effect modifiers-these were associated with superior exercise outcomes relative to non-exercise comparisons. Lower body mass index was also associated with better outcomes in exercise compared with no treatment/usual care. This study was limited by inconsistent availability and measurement of participant characteristics. CONCLUSIONS: This study provides potentially useful information to help treat patients and design future studies of exercise interventions that are better matched to specific subgroups. PROTOCOL PUBLICATION: https://doi.org/10.1186/2046-4053-1-64.

Anterior abdominal wall defects managed at a tertiary maternal-fetal medicine service in New Zealand: What counselling advice can we offer parents?

BACKGROUND: Anterior abdominal wall defects, including gastroschisis and omphalocoele, are common fetal anomalies. The management remains complicated, and their diagnosis may lead to significant parental distress. Effective parental counselling may impact on parental perceptions of the defect and help guide pregnancy management. AIMS: Using contemporary data, we aimed to describe clinical outcomes of patients with gastroschisis or omphalocoele in order to provide information for clinicians to assist in parental counselling. MATERIALS AND METHODS: We followed a case-series of patients with anterior abdominal wall defects referred to our regional Maternal Fetal Medicine services from 2011 to 2016. Outcomes of interest antenatally included details of diagnosis, associated anomalies and outcomes of pregnancy and postnatally included the nature of surgical repair, hospital stay and secondary complications until initial discharge. RESULTS: Eighty babies with gastroschisis were referred antenatally, and 72 were liveborn. Forty-nine babies with omphalocoele were referred antenatally, and 24 were liveborn. One further neonate with omphalocoele was postnatally diagnosed. Seventy-one neonates with gastroschisis progressed to operation, 30 developed complications post-surgery, and 68 survived until initial discharge. Twenty-two neonates with omphalocoele progressed to surgery, only two developed complications, and 21 survived until initial discharge. Eight of the surviving neonates with omphalocoele had associated structural abnormalities. The median hospital stay was 27 and eight days for gastroschisis and omphalocoele, respectively. CONCLUSION: Neonates with gastroschisis can have complex postnatal periods. Omphalocoele is associated with high antenatal mortality, especially in the presence of associated abnormalities; however, surviving neonates may have uneventful postnatal periods.

Sternal Route More Effective than Tibial Route for Intraosseous Amiodarone Administration in a Swine Model of Ventricular Fibrillation.

OBJECTIVE: The pharmacokinetics of IO administered lipid soluble amiodarone during ventricular fibrillation (VF) with ongoing CPR are unknown. This study measured mean plasma concentration over 5 minutes, maximum plasma concentration (Cmax), and time to maximum concentration (Tmax) of amiodarone administered by the sternal IO (SIO), tibial IO (TIO), and IV routes in a swine model of VF with ongoing CPR. METHODS: Twenty-one Yorkshire-cross swine were randomly assigned to three groups: SIO, TIO, and IV. Ventricular fibrillation was induced under general anesthesia. After 4 minutes in VF, 300 mg amiodarone was administered as indicated by group assignment. Serial blood specimens collected at 30, 60, 90, 120, 150, 180, 240, and 300 seconds were analyzed using high performance liquid chromatography with tandem mass spectrometry. RESULTS: The mean plasma concentration of IV amiodarone over 5 minutes was significantly higher than the TIO group at 60 seconds (P = 0.02) and 90 seconds (P = 0.017) post-injection. No significant differences in Cmax between the groups were found (P <0.05). The Tmax of amiodarone was significantly shorter in the SIO (99 secs) and IV (86 secs) groups compared to the TIO group (215 secs); P = 0.002 and P = 0.002, respectively. CONCLUSIONS: The SIO and IV routes of amiodarone administration were comparable. The TIO group took nearly three times longer to reach Tmax than the SIO and IV groups, likely indicating depot of lipid-soluble amiodarone in adipose-rich tibial yellow bone marrow. The SIO route was more effective than the TIO route for amiodarone delivery in a swine model of VF with ongoing CPR. Further investigations are necessary to determine if the kinetic differences found between the SIO and TIO routes in this study affect survival of VF in humans.

Personality and gender differences in global perspective.

Men's and women's personalities appear to differ in several respects. Social role theories of development assume gender differences result primarily from perceived gender roles, gender socialization and sociostructural power differentials. As a consequence, social role theorists expect gender differences in personality to be smaller in cultures with more gender egalitarianism. Several large cross-cultural studies have generated sufficient data for evaluating these global personality predictions. Empirically, evidence suggests gender differences in most aspects of personality-Big Five traits, Dark Triad traits, self-esteem, subjective well-being, depression and values-are conspicuously larger in cultures with more egalitarian gender roles, gender socialization and sociopolitical gender equity. Similar patterns are evident when examining objectively measured attributes such as tested cognitive abilities and physical traits such as height and blood pressure. Social role theory appears inadequate for explaining some of the observed cultural variations in men's and women's personalities. Evolutionary theories regarding ecologically-evoked gender differences are described that may prove more useful in explaining global variation in human personality.

Consensus on Exercise Reporting Template (CERT): Modified Delphi Study.

BACKGROUND: Exercise interventions are often incompletely described in reports of clinical trials, hampering evaluation of results and replication and implementation into practice. OBJECTIVE: The aim of this study was to develop a standardized method for reporting exercise programs in clinical trials: the Consensus on Exercise Reporting Template (CERT). DESIGN AND METHODS: Using the EQUATOR Network's methodological framework, 137 exercise experts were invited to participate in a Delphi consensus study. A list of 41 items was identified from a meta-epidemiologic study of 73 systematic reviews of exercise. For each item, participants indicated agreement on an 11-point rating scale. Consensus for item inclusion was defined a priori as greater than 70% agreement of respondents rating an item 7 or above. Three sequential rounds of anonymous online questionnaires and a Delphi workshop were used. RESULTS: There were 57 (response rate=42%), 54 (response rate=95%), and 49 (response rate=91%) respondents to rounds 1 through 3, respectively, from 11 countries and a range of disciplines. In round 1, 2 items were excluded; 24 items reached consensus for inclusion (8 items accepted in original format), and 16 items were revised in response to participant suggestions. Of 14 items in round 2, 3 were excluded, 11 reached consensus for inclusion (4 items accepted in original format), and 7 were reworded. Sixteen items were included in round 3, and all items reached greater than 70% consensus for inclusion. LIMITATIONS: The views of included Delphi panelists may differ from those of experts who declined participation and may not fully represent the views of all exercise experts. CONCLUSIONS: The CERT, a 16-item checklist developed by an international panel of exercise experts, is designed to improve the reporting of exercise programs in all evaluative study designs and contains 7 categories: materials, provider, delivery, location, dosage, tailoring, and compliance. The CERT will encourage transparency, improve trial interpretation and replication, and facilitate implementation of effective exercise interventions into practice.

Comparison of the effects of sternal and tibial intraosseous administered resuscitative drugs on return of spontaneous circulation in a swine model of cardiac arrest.

OBJECTIVE: Compare vasopressin, amiodarone, and epinephrine administration by sternal intraosseous (SIO), tibial intraosseous (TIO), and intravenous (IV) routes in a swine model of cardiac arrest. DESIGN: Prospective, randomized, between subjects, experimental design. SETTING: Laboratory. SUBJECTS: Male Yorkshire-cross swine (N = 35), seven per group. INTERVENTION: Swine were randomized to SIO, TIO, IV, cardiopulmonary resuscitation (CPR) with defibrillation, or CPR-only groups. Ventricular fibrillation (VF) was induced under general anesthesia. Mechanical CPR began 2 minutes postarrest. Vasopressin (40 U) was administered to the SIO, TIO, and IV groups 4 minutes postarrest. Defibrillation was performed and amiodarone (300 mg) was administered 6 minutes postarrest. Defibrillation was repeated, and epinephrine (1 mg) was administered 10 minutes postarrest. Defibrillation was repeated every 2 minutes and epinephrine repeated every 4 minutes until return of spontaneous circulation (ROSC) or 26 postarrest minutes elapsed. MAIN OUTCOME MEASURES: Rate of ROSC, time to ROSC, and odds of ROSC. RESULTS: There were no significant differences in rate of ROSC between the SIO and TIO (p = 0.22) or IV groups (p = 1.0). Time to ROSC was five times less in the SIO group than the TIO group (p = 0.003) but not compared to IV (p = 0.125). Time to ROSC in the IV group was significantly less than the TIO group (p = 0.04). Odds of ROSC for the SIO group were five times higher compared to the TIO group but same as IV. Odds of ROSC in the IV group were higher than the TIO group. CONCLUSION: There was a statistically significant delay in the time to ROSC and a clinically significant difference in odds of ROSC when resuscitative drugs, including lipophilic amiodarone, were administered by the TIO route compared to the SIO and IV routes in a swine model of sudden cardiac arrest. Further investigations are warranted to isolate the mechanism behind these findings.

Influence of directional preference on two clinical dichotomies: acute versus chronic pain and axial low back pain versus sciatica.

OBJECTIVE: To determine whether outcomes from treatment determined by subjects' directional preference (ie, reduction in back and/or leg pain, by performing a single direction of repeated end-range lumbar movement) would vary based on pain duration, location, or neurologic status. DESIGN: A secondary analysis of data from a multicenter randomized clinical trial. SETTING: Eleven physical therapy departments or clinics in 5 countries, with referrals for both acute and chronic low back pain. SUBJECTS: Seventy-one of 80 subjects with acute to chronic low back pain, and with and without radicular leg pain, and with or without mild neurologic deficit, were found at baseline to have a directional preference and were then treated with directional exercises that matched their directional preference. METHODS: All of the subjects were treated for 2 weeks with directional exercises and compatible posture modifications. Independent variables were pain duration, pain location, and neurologic status. MAIN OUTCOME MEASUREMENTS: Primary measures were back and leg pain intensity and function (Roland Morris Disability Questionnare). Secondary measures were activity interference, medication use, depression (Beck Depression Inventory), and a self-report of improvement. RESULTS: The subjects significantly improved their back and leg pain intensity, disability, and all secondary outcome measures, but pain duration, location, and neurologic status classification did not predict treatment responsiveness. Across all pain duration categories, 91%-100% either improved or resolved completely. There also was significant improvement across all pain location and neurologic status categories, with no significant differences across the outcome variables. CONCLUSIONS: In subjects found to have a directional preference who then treated themselves with matching directional exercises, neither pain duration nor pain location and neurologic status predicted their uniformly good-to-excellent outcomes.

The comparative prognostic value of directional preference and centralization: a useful tool for front-line clinicians?

A large number of prognostic factors have been associated with recovery from an episode of back pain, and much emphasis has been placed on psychosocial prognostic factors. The large number of prognostic factors and the lack of comparative analysis of different factors make use of these difficult in clinical practice. The aim of this study was to evaluate the comparative usefulness of a range of factors to predict outcome using data from a randomized controlled trial (RCT) in which 312 patients with sub-acute to chronic back pain received a mechanical evaluation and were sub-grouped based on the presence or absence of directional preference (DP). Patients were then randomized to treatment that was matched or unmatched to that DP. Patients with a minimal reduction of 30% in Roland-Morris Disability Questionnaire (RMDQ) score were defined as the good outcome group. Seventeen baseline variables were entered into a step-wise logistic regression analysis for the ability to predict a good outcome. Of the patients, 84 met the good outcome criteria and had a mean RMDQ decrease of 58.2% (9.8 points) in 4 visits. Leg pain, work status, depression, pain location, chronicity, and treatment assignment were significant predictors of outcome in univariate analysis. Only leg bothersomeness rating and treatment assignment survived multivariate analysis. Subjects with DP/centralization who received matched treatment had a 7.8 times greater likelihood of a good outcome. Matching patients to their DP is a stronger predictor of outcome than a range of other biopsychosocial factors.

Specific directional exercises for patients with low back pain: a case series.

PURPOSE: To determine whether outcomes could be changed after poor response to non-specific exercise therapy when the prescription was changed to specific, directional-preference exercises (McKenzie method). METHODS: Patients who participated in a randomized clinical trial (RCT) and the alternative care phase immediately following formed the cohort for this case series. In an earlier RCT, patients with directional preference were randomized to exercises/advice matched to their individual directional preference or to one of two unmatched protocols. The primary inclusion criterion for our case series was patient reports of being unchanged or worse following 2 weeks' treatment in the RCT. The secondary inclusion criterion was patient requests for "a change to one of the other stretching protocols to see if I can achieve better pain control." Patients meeting either of these criteria were offered matched exercises/advice if they had not previously received this intervention. Two-way repeated-measures ANOVA and McNemar tests compared outcomes during two consecutive time intervals: baseline to 2 weeks and 2 weeks to discharge. Dropouts were included in the intention-to-treat analysis. RESULTS: Four patients from the matched group met the primary inclusion criterion of "unchanged" (none reported being worse); 10 additional patients requested alternative treatment for better pain control (secondary criterion). Eighty-five patients from the two unmatched treatment groups met all the inclusion criteria, and an additional 22 patients met only the secondary criterion. These patients were offered matched treatment, and 96 consented. Those reporting improvement or resolution of symptoms were 22 % in the first two weeks of unmatched care (during the RCT) compared to 84 % with matched care. Statistically significant and clinically meaningful changes occurred in all outcomes (p < 0.001) after receiving matched care, compared to clinically unimportant changes with previous unmatched care during the RCT. CONCLUSIONS: Poor outcomes from non-specific/unmatched exercise protocols appeared to reverse when patients with directional preference were given sub-group-matched, direction-specific exercises. Because of the limitations of our study design, replication with a control group and longer-term follow-up are required to validate the findings.

Outcome of fetal cerebral posterior fossa anomalies.

INTRODUCTION: Limited data exist on the outcome of Dandy-Walker malformation (DWM), Dandy-Walker variant (DWV) and mega-cisterna magna (MCM). We report the first population-based study of posterior fossa anomalies from the northern region of England. METHODS: Cases were identified from the Northern Congenital Abnormality Survey (NorCAS) and regional Fetal Medicine Unit databases for the period 1986-2004 for DWM/V and 1995-2005 for MCM (defined as a cisterna magna > or =10 mm). Outcome data was obtained from pediatric records and/or general practitioner/health visitor questionnaires for all survivors. RESULTS: A prenatal diagnosis of a posterior fossa abnormality was made in 91 cases, with a further 12 cases of DWM/V diagnosed postnatally, giving incidences of DWM/V and MCM of 1/11574 and 1/8268 births respectively. In five cases where DWM/V was suspected prenatally, the diagnosis was not confirmed. Of the 47 with DWM/V, 41 (87%) had additional anomalies. There were three survivors, all with neurodevelopmental disability. Of the 39 cases of MCM, 24 (62%) had additional anomalies. There were 30 survivors; one child died at 3 months and the outcome was normal in 25 children including 12/13 (92%) with isolated MCM. SUMMARY: Posterior fossa anomalies are relatively common. The outcome is very poor in DWM/V owing to the high rate of associated anomalies. The outcome appears better with MCM, especially if this is an isolated finding.

Expression and interaction of the transcriptional coregulators, CBP/p300, in the human myometrium during pregnancy and labor.

OBJECTIVE: In humans, the factors that govern the switch from myometrial quiescence to coordinated contractions at the initiation of labor are not well defined. Recent studies have highlighted a role for the coactivator, CREB binding protein (CBP), in the human myometrium during pregnancy and labor through its ability to acetylate histones. In the present study, the expression of CBP and its related coactivator, p300, were examined. METHODS: Levels and interactions of CBP and its paralogue p300 were determined by Western blotting, immunohistochemistry, and coimmunoprecipitation experiments using myometrial biopsy samples from nonpregnant (NP), pregnant nonlaboring (P), and spontaneously laboring (SL) women. RESULTS: Levels of CBP were seen to increase in term P myometrial samples but were then greatly reduced in SL myometrium. In contrast, levels of p300 remained uniform between NP, P, and SL tissues. These observations were confirmed by immunhistochemical analyses. Immunoprecipitation experiments highlighted that CBP was able to interact with CREB, CREM, ATF-2, and p300 in P lower segment myometrium. CONCLUSION: Recent evidence suggests that competition for CBP plays an important role in regulating gene expression during cell growth. Consequently our data suggest that the increase in myometrial CBP levels during pregnancy may occur to meet this increase in CBP demand. Moreover, from coimmunoprecipitation experiments, this increase in CBP expression would be expected to facilitate the transactivation potential of the cyclic adenosine monophosphate (cAMP)-dependent transcription factors CREB, CREM, and ATF-2.

Does it matter which exercise? A randomized control trial of exercise for low back pain.

STUDY DESIGN: Multicentered randomized controlled trial. OBJECTIVES: To determine if previously validated low back pain (LBP) subgroups respond differently to contrasting exercise prescriptions. SUMMARY OF BACKGROUND DATA: The role of "patient-specific" exercises in managing LBP is controversial. METHODS: A total of 312 acute, subacute, and chronic patients, including LBP-only and sciatica, underwent a standardized mechanical assessment classifying them by their pain response, specifically eliciting either a "directional preference" (DP) (i.e., an immediate, lasting improvement in pain from performing either repeated lumbar flexion, extension, or sideglide/rotation tests), or no DP. Only DP subjects were randomized to: 1) directional exercises "matching" their preferred direction (DP), 2) exercises directionally "opposite" their DP, or 3) "nondirectional" exercises. Outcome measures included pain intensity, location, disability, medication use, degree of recovery, depression, and work interference. RESULTS: A DP was elicited in 74% (230) of subjects. One third of both the opposite and non-directionally treated subjects withdrew within 2 weeks because of no improvement or worsening (no matched subject withdrew). Significantly greater improvements occurred in matched subjects compared with both other treatment groups in every outcome (P values <0.001), including a threefold decrease in medication use. CONCLUSIONS: Consistent with prior evidence, a standardized mechanical assessment identified a large subgroup of LBP patients with a DP. Regardless of subjects' direction of preference, the response to contrasting exercise prescriptions was significantly different: exercises matching subjects' DP significantly and rapidly decreased pain and medication use and improved in all other outcomes. If repeatable, such subgroup validation has important implications for LBP management.