Genetic basis of Arabidopsis thaliana responses to infection by naïve and adapted isolates of turnip mosaic virus.

Plant viruses account for enormous agricultural losses worldwide, and the most effective way to combat them is to identify genetic material conferring plant resistance to these pathogens. Aiming to identify genetic associations with responses to infection, we screened a large panel of Arabidopsis thaliana natural inbred lines for four disease-related traits caused by infection by A. thaliana-naïve and -adapted isolates of the natural pathogen turnip mosaic virus (TuMV). We detected a strong, replicable association in a 1.5 Mb region on chromosome 2 with a 10-fold increase in relative risk of systemic necrosis. The region contains several plausible causal genes as well as abundant structural variation, including an insertion of a Copia transposon into a Toll/interleukin receptor (TIR-NBS-LRR) coding for a gene involved in defense, that could be either a driver or a consequence of the disease-resistance locus. When inoculated with TuMV, loss-of-function mutant plants of this gene exhibited different symptoms than wild-type plants. The direction and severity of symptom differences depended on the adaptation history of the virus. This increase in symptom severity was specific for infections with the adapted isolate. Necrosis-associated alleles are found worldwide, and their distribution is consistent with a trade-off between resistance during viral outbreaks and a cost of resistance otherwise, leading to negative frequency-dependent selection.

A large-effect fitness trade-off across environments is explained by a single mutation affecting cold acclimation.

Identifying the genetic basis of local adaptation and fitness trade-offs across environments is a central goal of evolutionary biology. Cold acclimation is an adaptive plastic response for surviving seasonal freezing, and costs of acclimation may be a general mechanism for fitness trade-offs across environments in temperate zone species. Starting with locally adapted ecotypes of Arabidopsis thaliana from Italy and Sweden, we examined the fitness consequences of a naturally occurring functional polymorphism in CBF2. This gene encodes a transcription factor that is a major regulator of cold-acclimated freezing tolerance and resides within a locus responsible for a genetic trade-off for long-term mean fitness. We estimated the consequences of alternate genotypes of CBF2 on 5-y mean fitness and fitness components at the native field sites by comparing near-isogenic lines with alternate genotypes of CBF2 to their genetic background ecotypes. The effects of CBF2 were validated at the nucleotide level using gene-edited lines in the native genetic backgrounds grown in simulated parental environments. The foreign CBF2 genotype in the local genetic background reduced long-term mean fitness in Sweden by more than 10%, primarily via effects on survival. In Italy, fitness was reduced by more than 20%, primarily via effects on fecundity. At both sites, the effects were temporally variable and much stronger in some years. The gene-edited lines confirmed that CBF2 encodes the causal variant underlying this genetic trade-off. Additionally, we demonstrated a substantial fitness cost of cold acclimation, which has broad implications for potential maladaptive responses to climate change.

Quantitative detection of RAS and KKS peptides in COVID-19 patient serum by stable isotope dimethyl labeling LC-MS.

Angiotensin and kinin metabolic pathways are reported to be altered by many diseases, including COVID-19. Monitoring levels of these peptide metabolites is important for understanding mechanisms of disease processes. In this paper, we report dimethyl labeling of amines in peptides by addition of formaldehyde to samples and deutero-formaldehyde to internal standards to generate nearly identical isotopic standards with 4 m/z units larger per amine group than the corresponding analyte. We apply this approach to rapid, multiplexed, absolute LC-MS/MS quantitation of renin angiotensin system (RAS) and kallikrein-kinin system (KKS) peptides in human blood serum. Limits of detection (LODs) were obtained in the low pg mL-1 range with 3 orders of magnitude dynamic ranges, appropriate for determinations of normal and elevated levels of the target peptides in blood serum and plasma. Accuracy is within ±15% at concentrations above the limit of quantitation, as validated by spike-recovery in serum samples. Applicability was demonstrated by measuring RAS and KKS peptides in serum from COVID-19 patients, but is extendable to any class of peptides or other small molecules bearing reactive -NH2 groups.

Comparison of the PROMIS and iHOT-12 in Determining Satisfaction Levels After Hip Arthroscopy for FAIS.

Background: The Patient-Reported Outcomes Measurement Information System (PROMIS) has not been fully evaluated for outcomes assessment after hip arthroscopy to correct femoroacetabular impingement syndrome (FAIS). Purpose/Hypothesis: The purpose of this study was to compare the accuracy of the PROMIS Physical Function (PF) and Pain Interference (PI) subscales with the 12-Item International Hip Outcome Tool (iHOT-12) to define patients with 3 unique substantial clinical benefit (SCB) scores-patients who reported ≥80%, ≥90%, and 100% satisfaction at 1 year after hip arthroscopy for FAIS. We hypothesized that the iHOT-12 would be more accurate than the PROMIS-PF and PROMIS-PI subscales in identifying these 3 patient groups. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: We reviewed the records of patients who underwent hip arthroscopy for symptomatic FAIS at 3 centers from January 2019 through June 2021 and had 1-year clinical and radiographic follow-up data. Patients completed the iHOT-12, PROMIS-PF, and PROMIS-PI on initial assessment and at 1 year (±30 days) postoperatively. Postoperative satisfaction was reported on an 11-category scale with anchors defined as "0% satisfied" and "100% satisfied." Receiver operator characteristic analysis was performed to determine the absolute SCB values for the iHOT-12 and PROMIS subscales that would most accurately identify those patients who reported ≥80%, ≥90%, and 100% satisfaction. Area under the curve (AUC) values and 95% CIs for the 3 instruments were compared. Results: Included were 163 patients (111 [68%] women and 52 [32%] men), with a mean age of 26.1 years. Corresponding absolute SCB scores for patients who reported ≥80%, ≥90%, and 100% satisfaction were as follows: iHOT-12, 68.4, 72.1, 74.7; PROMIS-PF, 45, 47.7, 49.9; and PROMIS-PI, 55.9, 52.4, 51.9. The AUC ranged between 0.67 and 0.82, with overlapping 95% CIs indicating a minimal difference in accuracy between the 3 instruments. Sensitivity and specificity values ranged between 0.61 and 0.82. Conclusion: The PROMIS-PF and PROMIS-PI subscales were as accurate as the iHOT-12 in defining absolute SCB scores for patients reporting ≥80%, ≥90%, and 100% satisfaction at 1-year follow-up after hip arthroscopy for FAIS.

Addition of Pericapsular Nerve Group and Transversus Abdominis Plane Blocks Significantly Reduces Opioid Use in Patients Undergoing Concomitant Hip Arthroscopy and Periacetabular Osteotomy.

INTRODUCTION: Previous studies have evaluated the effect of the pericapsular nerve group block for hip arthroscopy and the transverse abdominis plane block for periacetabular osteotomy and have shown decreased narcotic consumption in both groups. No published study has evaluated the effectiveness of combining the blocks when performing hip arthroscopy and periacetabular osteotomy under the same general anesthesia. It was hypothesized that patients treated for hip dysplasia with hip arthroscopy and concomitant periacetabular osteotomy using a pericapsular nerve group block, transverse abdominis plane block, and general anesthesia would have decreased postoperative pain and require less narcotic consumption than those undergoing the procedure with general anesthetic alone.  Methods: A single surgeon performed a retrospective analysis of consecutive patients undergoing concomitant hip arthroscopy and periacetabular osteotomy between 11/2020 and 6/2021. Fifteen consecutive patients undergoing the procedure with a general anesthetic alone (no-block group) were compared to 15 patients undergoing the same procedure with a combined pericapsular nerve group block, transverse abdominis plane block, and general anesthetic (block group). Hip arthroscopy was performed utilizing a post-free technique, and a rectus sparing approach was used for the periacetabular osteotomy. The nerve blocks were performed by multiple anesthesiologists using previously published methods. Operating room time, length of stay, visual analog scale pain scores, and total narcotic consumption in morphine milliequivalents were analyzed. Groups were compared using the chi-squared test for non-continuous demographic variables and a two-tailed t-test for continuous variables utilizing Microsoft Excel (Microsoft, Redmond, WA, USA), p-value set at 0.05 for significance.  Results: The no-block group consisted of 14 females and one male, while the block group was all females. No significant differences were observed between age, sex, BMI, surgery time, length of stay, or procedures performed, p>0.05. The maximal visual analog scale score in the post-anesthesia care unit was 8 ± 1.3 vs. 7 ± 1.9 in the no-block vs. block groups, respectively, p=0.15. The average hospital floor visual analog scale score was 5.7 ± 1.3 vs. 4.8 ± 1.3 in the no-block vs. block groups, respectively, p=0.07. Total pain medications required were 217.6 ± 54.6 vs. 154 ± 41.9 morphine milliequivalents in the no-block vs. block groups, respectively, p=0.001. No complications were reported in either group, and no patient in the block group demonstrated motor nerve palsy or postoperative fall. CONCLUSION:  This study demonstrated that patients undergoing combined hip arthroscopy and periacetabular osteotomy for symptomatic acetabular dysplasia who had pericapsular nerve group, transverse abdominal plane block, and general anesthesia required fewer narcotics in the first 24 hours after surgery compared to those who had general anesthesia alone.

Females with hip-related pain display altered lower limb mechanics compared to their healthy counterparts in a drop jump task.

BACKGROUND: Hip-related pain describes femoroacetabular impingement syndrome, acetabular dysplasia, and other hip pain conditions without clear morphological features. Movement strategies in this population, notably sex-related patterns, are poorly understood and may provide insights into why females report more pain and worse function. This study examined the sex-related differences during a drop vertical jump task between those with hip-related pain and healthy controls. METHODS: Patients with hip-related pain and healthy controls completed five repetitions of a drop jump while their kinematics and kinetics were recorded using a motion capture system and force plates. Hip, knee, and ankle joint angles and external joint moments during landing were used in general estimating equations for comparison of group by sex by limb interactions. Time series data were further investigated using statistical parametric mapping. FINDINGS: Females with hip-related pain had 9.1° less hip flexion (P = .041) and 9.2° less knee flexion (P = .024) than healthy females, and 8.3° less knee flexion than male counterparts with hip-related pain (P = .039). Males demonstrated 1.4° less hip flexion on the affected side compared to their uninvolved side (P = .004). Statistical parametric mapping results showed significant differences in knee flexion angle for females with hip-related pain compared to healthy females (P = .042). There were no significant differences in hip, knee, or ankle moments. INTERPRETATION: Females with hip-related pain showed kinematic patterns distinct from healthy controls. Sex may be an important variable of interest in characterizing movement impairments in this population and movement impairments may be an appropriate target for intervention for these patients.

Preoperative Pericapsular Nerve Group Block Results in Less Pain, Decreased Narcotic Use, and Quicker Discharge Time Than No Block in Patients Who Were Surgically Treated for Femoroacetabular Impingement Syndrome.

Purpose: To determine the effectiveness of pericapsular nerve group (PENG) block for patients surgically treated for femoroacetabular impingement syndrome (FAIS). Methods: Consecutive patients who underwent surgical treatment of FAIS either with or without preoperative PENG block by a single surgeon were retrospectively identified. Twenty-five patients who received PENG block were matched 1:1 by age, sex, body mass index, and procedure to 25 patients who received no block (NB). A retrospective review of the medical records of consecutive patients undergoing the PENG block was performed. Outcome measures of postanesthesia care unit visual analog scale initial (PACU VAS-initial), maximum (PACU VAS-max), discharge (PACU VAS-discharge), intraoperative fentanyl, pain medications in morphine equivalents (ME), and PACU to discharge times were recorded. Results: Twenty-five patients undergoing a PENG block and 25 patients who did not undergo a block (NB) were identified. No significant differences observed between age, sex, body mass index, surgery time, or procedures performed between the PENG and NB groups, P > .05. Significantly less VAS-initial was observed in the PENG group 3.7 ± 3.2, versus 5.5 ± 2.9 in the NB group, P = .04. Fentanyl usage intraoperatively was 137.3 ± 53.3 µg versus 108.5 ± 39.6 µg in NB versus PENG group respectively, P = .04. Narcotic use was 50.29 ± 11.2 ME versus 34.3 ± 12.1 ME in NB versus PENG group respectively, P = .001. PACU to discharge time was 95.8 ± 31 minutes versus 81.5 ± 19 minutes in NB versus PENG group, respectively, P = .05. No patient in the PENG group demonstrated a motor nerve palsy. Conclusions: For patients undergoing hip arthroscopy for FAIS, the addition of a preoperative PENG block showed a significant decrease in initial PACU pain, PACU narcotic consumption, intraoperative fentanyl usage, and quicker time to discharge without complications when compared to a no block, post-free control group. Level of Evidence: III, retrospective cohort study.

Climate drives rhizosphere microbiome variation and divergent selection between geographically distant Arabidopsis populations.

Disentangling the contribution of climatic and edaphic factors to microbiome variation and local adaptation in plants requires an experimental approach to uncouple their effects and test for causality. We used microbial inocula, soil matrices and plant genotypes derived from two natural Arabidopsis thaliana populations in northern and southern Europe in an experiment conducted in climatic chambers mimicking seasonal changes in temperature, day length and light intensity of the home sites of the two genotypes. The southern A. thaliana genotype outperformed the northern genotype in the southern climate chamber, whereas the opposite was true in the northern climate chamber. Recipient soil matrix, but not microbial composition, affected plant fitness, and effects did not differ between genotypes. Differences between chambers significantly affected rhizosphere microbiome assembly, although these effects were small in comparison with the shifts induced by physicochemical differences between soil matrices. The results suggest that differences in seasonal changes in temperature, day length and light intensity between northern and southern Europe have strongly influenced adaptive differentiation between the two A. thaliana populations, whereas effects of differences in soil factors have been weak. By contrast, below-ground differences in soil characteristics were more important than differences in climate for rhizosphere microbiome differentiation.

A comparison of 6-month outcomes between periacetabular osteotomy with concomitant hip arthroscopy to isolated hip arthroscopy for femoroacetabular impingement.

PURPOSE: To compare early outcomes of periacetabular osteotomy (PAO) with concomitant hip arthroscopy to isolated hip arthroscopy for femoroacetabular impingement (FAI) and chondrolabral pathology using patient-reported outcomes measurement information system (PROMIS). MATERIALS AND METHODS: Consecutive patients scheduled for PAO with concomitant hip arthroscopy (PAO + HA) or isolated hip arthroscopy (HA) between the ages of 15 and 30 years old were prospectively included in the study. Based on power analysis, subjects were recruited until there were 22 subjects in the PAO + HA group. These subjects were then gender matched to the HA group. The PROMIS, with six subscales and two global health measures, were completed during preoperative and 6-month follow-up visits. One-way ANOVA was performed to compare intake information of age, symptom duration, body mass index, and Beighton scores as well as preoperative and 6-month postoperative PROMIS scores between the PAO + HA and HA. RESULTS: 22 consecutive subjects undergoing PAO + HA were all females (average age 20.0 years) and matched to 22 consecutive females (average age 22.6) in the HA group. ANOVA did not find a significant difference between the two groups when comparing intact information, with exception of age (p = 0.04). A significant difference was also not identified (p ≥ 0.05) between the two groups on preoperative or 6-month postoperative PROMIS scores. The largest difference in 6-month postoperative scores between the two groups was 4.4 points on physical function subscale. CONCLUSION: Outcomes at 6 months were not significantly different when comparing PAO + HA to HA for FAI and chondrolabral pathology in females under 30 years of age. The more extensive surgery with a prolonged protective period associated with PAO do not seem to negatively impact outcomes at 6 months when compared to HA. These finding support the use of PAO + HA, particularly if the patient and/or surgeon were concerned about prolonged disability, metal health issues, and/or higher pain levels that might be associated with the PAO procedure.

Post-Related Complications in Hip Arthroscopy Are Reported Significantly Greater in Prospective Versus Retrospective Literature: A Systematic Review.

PURPOSE: To determine whether there are differences in (1) the incidence of post-related complications following hip arthroscopy between prospective and retrospective publications; and (2) between post-assisted and postless techniques. METHODS: A systematic review was performed using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines to characterize post-related complications following hip arthroscopy for central or peripheral compartment hip pathology, including femoroacetabular impingement syndrome and chondrolabral injury. Inclusion criteria were prospective and retrospective Level I-IV evidence investigations that reported results of hip arthroscopy performed in the supine position. Exclusion criteria included open or extra-articular endoscopic hip surgery. Post-related complications included pudendal nerve injury (sexual dysfunction, dyspareunia, perineal pain or numbness) or perineum/external genitalia soft-tissue injury. RESULTS: Ninety-four studies (12,212 hips; 49% male, 51% female; 52% Level IV evidence) were analyzed. Prospective studies (3,032 hips) report a greater incidence of post-related complications compared with retrospective (8,116 hips) studies (7.1% vs 1.4%, P < .001). Three studies (1,064 hips) used a postless technique and all reported a 0% incidence of pudendal neurapraxia or perineal soft tissue injury. Most pudendal nerve complications were transient, resolving by 3 months, but permanent nerve injury was reported in 4 cases. Only 19%, 22%, 7%, and 4% of studies reported a total surgery time, traction time, traction force, and bed Trendelenburg angle for their study samples, respectively. CONCLUSIONS: The incidence of post-related complications is 5 times greater in prospective (versus retrospective) hip arthroscopy literature. Postless distraction resulted in a 0% incidence of post-related injuries. LEVEL OF EVIDENCE: IV, systematic review of Level I-IV evidence.

Use of continuous passive motion device after arthroscopic hip surgery decreases post-operative pain: A randomized controlled trial.

BACKGROUND: We sought to determine whether continuous passive motion (CPM) usage improves outcomes following arthroscopic hip surgery involving acetabular labral repair. Our hypothesis is that CPM usage reduces pain and pain medication use and improves quality of life in individuals who undergo hip arthroscopy. METHODS: We created a randomized controlled trial consisting of 54 patients who underwent arthroscopic acetabular labral repair. Patients were randomized to two groups, one with CPM use post-operatively and one without. Primary outcomes measured were pain level, patient satisfaction, and quality of life. Parameters used to measure these outcomes were self-reported pain scores on Likert scale, frequency of analgesic medication use, and self-reported scores on Hip Outcome Score Activity of Daily Living (HOS ADL). These parameters were compared between the two randomized groups using t-test for statistical analysis. RESULTS: There was no statistical difference between the treatment and control groups in terms of patient characteristics. There was no statistical difference between the two groups in terms of HOS ADL scores, although the patients in the control group demonstrated a trend toward higher HOS ADL scores. The patients in the CPM group had a statistically significant decrease in pain levels after surgery compared to patients in the control group. The total morphine equivalent dose consumed in the first two post-operative weeks was higher in the control group compared to the CPM group, although this difference was not statistically significant. CONCLUSIONS: Use of CPM resulted in lower pain level scores in patients after hip arthroscopy. Although there is no statistical difference in quality of life or quantity of analgesics consumed post-operatively, patients who used CPM tended to have lower HOS ADL scores (which is desirable) and less consumption of pain medication. A study with a larger sample of patients might elucidate more differences between the two groups. LEVEL OF EVIDENCE: II, therapeutic.

The Key Parts of Hip Arthroscopy for Femoroacetabular Impingement Syndrome: Implications for the Learning Curve.

BACKGROUND: Hip arthroscopy is a rapidly growing surgical approach to treat femoroacetabular impingement (FAI) syndrome with a significant learning curve pertaining to complication risk, reoperation rate, and total hip arthroplasty conversion. Hip arthroscopy is more frequently being taught in residency and fellowship training. The key, or critical, parts of the technique have not yet been defined. PURPOSE: To identify the key components required to perform arthroscopic treatment of FAI syndrome. STUDY DESIGN: Consensus statement. METHODS: A 3-question survey comprising questions on hip arthroscopy for FAI was sent to a convenience sample of 101 high-volume arthroscopic hip surgeons in the United States. Surgeon career length (years) and maintenance volume (cases per year) were queried. Hip arthroscopy was divided into 10 steps using a Delphi technique to achieve a convergence of expert opinion. A step was considered "key" if it could (1) avoid complications, (2) reduce risk of revision arthroscopy, (3) reduce risk of total hip arthroplasty conversion, or (4) optimize patient-reported outcomes. Based on previous literature, steps with >90% of participants were defined as key. Descriptive and correlation statistics were calculated. RESULTS: A total of 64 surgeons (63% response rate) reported 5.6 ± 2.1 steps as key (median, 6; range, 1-9). Most surgeons (56.3%) had been performing hip arthroscopy for >5 years. Most surgeons (71.9%) had performed >100 hip arthroscopy procedures per year. Labral treatment (97% agreement) and cam correction (91% agreement) were the 2 key steps of hip arthroscopy for FAI. Pincer/subspine correction (86% agreement), dynamic examination before capsular closure (63% agreement), and capsular management/closure (63% agreement) were selected by a majority of respondents but did not meet the study definition of key. There was no significant correlation between surgeon experience and designation of certain steps as key. CONCLUSION: Based on a Delphi technique and expert opinion survey of high-volume surgeons, labral treatment and cam correction are the 2 key parts of hip arthroscopy for FAI syndrome.

Life-history trade-offs and the genetic basis of fitness in Arabidopsis thaliana.

Resources allocated to survival cannot be used to increase fecundity, but the extent to which this trade-off constrains adaptation depends on overall resource status. Adaptation to local environmental conditions may therefore entail the evolution of traits that increase the amount of resources available to individuals (their resource status or 'condition'). We examined the relative contribution of trade-offs and increased condition to adaptive evolution in a recombinant inbred line population of Arabidopsis thaliana planted at the native sites of the parental ecotypes in Italy and Sweden in 2 years. We estimated genetic correlations among fitness components based on genotypic means and explored their causes with QTL mapping. The local ecotype produced more seeds per fruit than did the non-local ecotype, reflected in stronger adaptive differentiation than was previously shown based on survival and fruit number only. Genetic correlations between survival and overall fecundity, and between number of fruits and number of seeds per fruit, were positive, and there was little evidence of a trade-off between seed size and number. Quantitative trait loci for these traits tended to map to the same regions of the genome and showed positive pleiotropic effects. The results indicate that adaptive differentiation between the two focal populations largely reflects the evolution of increased ability to acquire resources in the local environment, rather than shifts in the relative allocation to different life-history traits. Differentiation both in phenology and in tolerance to cold is likely to contribute to the advantage of the local genotype at the two sites.

Worse Preoperative Pain and Higher Activity Levels Predict Patient Choice of Formal Physical Therapy After Primary Anterior Total Hip Arthroplasty.

BACKGROUND: The purpose of this randomized controlled trial is (1) to compare the efficacy of supervised formal physical therapy (PT) and self-directed home exercises and (2) to identify independent predictors of transitioning from self-directed home exercises to supervised formal PT following total hip arthroplasty (THA) via an anterior approach. METHODS: After Institutional Review Board approval, 147 patients undergoing primary unilateral THA through anterior approach were enrolled and randomized to receive either clinic or home-based PT. Surveys with Hip Disability Osteoarthritis Outcome Scores (HOOS) and Short Form-12 Health Survey scores for both groups were obtained before surgery and at 6, 14, and 24 weeks after surgery. Patients had the option to transition into the other study group at their 6-week follow-up visit. RESULTS: Of the 147 patients enrolled, final analysis included scores for 136 patients. Forty-two (63.6%) of the 66 patients randomized to the supervised formal PT group crossed over to self-directed home exercise group and 12 (17.1%) of the 70 patients randomized to the self-directed home exercise group crossed over to supervised formal PT group. There were no significant (P > .05) differences between groups at all time points for the overall HOOS and Short Form-12 Health Survey. Subjects with worse preoperative pain scores (P = .005) and higher HOOS preoperative activity of daily living scores (P = .015) were more likely to transition from the home exercise group to formal PT group. CONCLUSION: There were no significant outcome score differences between subjects undergoing supervised formal PT and self-directed home exercises. However, patients reporting worse preoperative pain and higher preoperative activity levels may prefer supervised formal PT compared to self-directed home exercises after undergoing primary anterior THA.

Allocation of Anchors During Labral Repair: A Multicenter Cohort Analysis of Labral Treatment in Hip Arthroscopy.

BACKGROUND: While previous studies have established several techniques for suture anchor repair of the acetabular labrum to bone during arthroscopic surgery, the current literature lacks evidence defining the appropriate number of suture anchors required to effectively restore the function of the labral tissue. PURPOSE/HYPOTHESIS: To define the location and size of labral tears identified during hip arthroscopy for acetabular labral treatment in a large multicenter cohort. The secondary purpose was to differentiate the number of anchors used during arthroscopic labral repair. The hypothesis was that the location and size of the labral tear as well as the number of anchors identified would provide a range of fixation density per acetabular region and fixation method to be used as a guide in performing arthroscopic repair. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: We used a multicenter registry of prospectively collected hip arthroscopy cases to find patients who underwent arthroscopic labral repair by 1 of 7 orthopaedic surgeons between January 2015 and January 2017. The tear location and number of anchors used during repair were described using the clockface method, where 3 o'clock denoted the anterior extent of the tear and 9 o'clock the posterior extent, regardless of sidedness (left or right). Tear size was denoted as the number of "hours" spanned per clockface arc. Chi-square and univariate analyses of variance were performed to evaluate the data for both the entire group and among surgical centers. RESULTS: A total of 1978 hips underwent arthroscopic treatment of the acetabular labrum; the most common tear size had a 3-hour span (n = 820; 41.5%). Of these hips, 1645 received labral repair, with most common repair location at the 12- to 3-o'clock position (n = 537; 32.6%). The surgeons varied in number of anchors per repair according to labral size (P < .001 for all), using 1 to 1.6 anchors for 1-hour tears, 1.7 to 2.4 anchors for 2-hour tears, 2.1 to 3.2 anchors for 3-hour tears, and 2.2 to 4.1 for 4-hour tears. CONCLUSION: Variation existed in the number of anchor implants per tear size. When labral repair involved a mean clockface arc >2 hours, at least 2 anchor points were fixated.

Synchrotron FTIR spectromicroscopy as a tool for studying populations and individual living cells of green algae.

Fourier transform infrared (FTIR) spectromicroscopy was used to study individual living cells of three closely-related species of the green algal genus Chlamydomonas. Three types of spectral variation were observed between individual cells within a single culture, as well as between different cultures: variation around a mean, individual outliers, and the presence of subpopulations. By understanding and controlling this variation, we were able to spectroscopically differentiate between the three closely-related species. Spectral differences were confirmed using principal component analysis, leading to an understanding of the biochemical differences between species. This work highlights the additional information obtained by studying individual cells, and has implications for more traditional bulk measurements.

Hip arthroscopy for lateral cam morphology: how important are the vessels?

The purpose of this narrative review is to identify the anatomy and relevant blood supply to the femoral head as it pertains to hip arthroscopy and lateral cam morphology. The primary blood supply to the femoral head is the lateral ascending superior retinacular vessels, which are terminal branches of the medial femoral circumflex artery. These vessels penetrate the femoral head at the posterolateral head-neck junction. Surgeons performing posterolateral femoral osteoplasty must respect this vasculature to avoid iatrogenic avascular necrosis (AVN). Avoidance of excessive traction, avoidance of distal posterolateral capsulotomy and avoidance of disruption of the superior retinacular vessels should keep the risk for AVN low. Hip extension, internal rotation and distraction are useful in hip arthroscopy to better visualize lateral/posterolateral cam morphology to facilitate an accurate comprehensive cam correction and avoid vascular disruption.

HPV-EM: an accurate HPV detection and genotyping EM algorithm.

Accurate HPV genotyping is crucial in facilitating epidemiology studies, vaccine trials, and HPV-related cancer research. Contemporary HPV genotyping assays only detect < 25% of all known HPV genotypes and are not accurate for low-risk or mixed HPV genotypes. Current genomic HPV genotyping algorithms use a simple read-alignment and filtering strategy that has difficulty handling repeats and homology sequences. Therefore, we have developed an optimized expectation-maximization algorithm, designated HPV-EM, to address the ambiguities caused by repetitive sequencing reads. HPV-EM achieved 97-100% accuracy when benchmarked using cell line data and TCGA cervical cancer data. We also validated HPV-EM using DNA tiling data on an institutional cervical cancer cohort (96.5% accuracy). Using HPV-EM, we demonstrated HPV genotypic differences in recurrence and patient outcomes in cervical and head and neck cancers.