Distribution and abundance of tetraether lipid cyclization genes in terrestrial hot springs reflect pH.

Many Archaea produce membrane-spanning lipids that enable life in extreme environments. These isoprenoid glycerol dibiphytanyl glycerol tetraethers (GDGTs) may contain up to eight cyclopentyl and one cyclohexyl ring, where higher degrees of cyclization are associated with more acidic, hotter or energy-limited conditions. Recently, the genes encoding GDGT ring synthases, grsAB, were identified in two Sulfolobaceae; however, the distribution and abundance of grs homologs across environments inhabited by these and related organisms remain a mystery. To address this, we examined the distribution of grs homologs in relation to environmental temperature and pH, from thermal springs across Earth, where sequences derive from metagenomes, metatranscriptomes, single-cell and cultivar genomes. The abundance of grs homologs shows a strong negative correlation to pH, but a weak positive correlation to temperature. Archaeal genomes and metagenome-assembled genomes (MAGs) that carry two or more grs copies are more abundant in low pH springs. We also find grs in 12 archaeal classes, with the most representatives in Thermoproteia, followed by MAGs of the uncultured Korarchaeia, Bathyarchaeia and Hadarchaeia, while several Nitrososphaeria encodes >3 copies. Our findings highlight the key role of grs-catalysed lipid cyclization in archaeal diversification across hot and acidic environments.

Vertical shear pelvic injury: evaluation, management, and fixation strategies.

Vertical shear pelvic ring fractures are rare and account for less than 1% of all fractures. Unlike severely displaced antero-posterior compression and lateral compression pelvic fractures, patients' mortality is lower. Nevertheless, patients must be managed acutely using well-defined ATLS protocols and institution-specific protocols for haemodynamically unstable pelvic ring fractures. The definitive treatment of vertical shear pelvic fractures is however more controversial with a paucity of literature to recommend the ideal reduction and fixation strategy. While the majority of injuries can be reduced and fixed in a closed manner, orthopaedic traumatologists should be familiar with the contraindications to those techniques as well as options such as tension band plating and lumbo pelvic fixation. Our paper reviews the acute management, associated injuries and definitive reduction and fixation strategies of vertical shear pelvic fractures. In addition, we propose a treatment algorithm for the selection of the most appropriate fixation technique.

Atypical femur fractures in patients receiving bisphosphonate therapy: etiology and management.

Osteoporosis is a growing problem that is projected to affect more than 50% of American adults by 2020. Bisphosphonate therapy is currently the primary mode of treating osteoporosis in this population. While bisphosphonate therapy has been successful in increasing bone mineral density, data has shown an increased risk of atypical femur fractures with prolonged therapy. Atypical femur fractures are characterized by low-energy or atraumatic injuries that occur in the subtrochanteric region. They originate on the medial cortex, travel transversely, and typically have little or no comminution. Conservative therapy is indicated for patients with incomplete fractures without prodromal symptoms. Patients with incomplete fractures and significant prodromal symptoms or visible fracture line on radiographs, those who have failed conservative management, and those with complete fractures should be treated with intramedullary nail fixation. Evaluation should involve imaging of the contralateral femur. Teriparatide therapy may be considered for patients without contraindications. While the incidence of these fractures is low, it is likely that these rates will increase with the aging population and increased prevalence of patients being treated with bisphosphonate therapy.

Incidence of Hansen's Disease--United States, 1994-2011.

Hansen's disease (HD), or leprosy, is caused by the bacterium Mycobacterium leprae and is reportable in many states. It is a chronic disease affecting the skin and nerves, commonly presenting as pale or reddish skin patches with diminished sensation. Without treatment, it can progress to a severely debilitating disease with nerve damage, tissue destruction, and functional loss. An important factor in limiting HD morbidity is early diagnosis and prompt initiation of therapy. Because HD is rare, clinicians in the United States are often unfamiliar with it; however, HD continues to cause morbidity in the United States. To better characterize at-risk U.S. populations, HD trends during 1994-2011 were evaluated by reviewing records from the National Hansen's Disease Program (NHDP). When the periods 1994-1996 and 2009-2011 were compared, a decline in the rate for new diagnoses from 0.52 to 0.43 per million was observed. The rate among foreign-born persons decreased from 3.66 to 2.29, whereas the rate among U.S.-born persons was 0.16 in both 1994-1996 and 2009-2011. Delayed diagnosis was more common among foreign-born persons. Clinicians throughout the United States should familiarize themselves with the signs and symptoms of HD and understand that HD can occur in the United States.

Dual RNA-seq in filarial nematodes and Wolbachia endosymbionts using RNase H based ribosomal RNA depletion.

Lymphatic filariasis is caused by parasitic nematodes and is a leading cause of disability worldwide. Many filarial worms contain the bacterium Wolbachia as an obligate endosymbiont. RNA sequencing is a common technique used to study their molecular relationships and to identify potential drug targets against the nematode and bacteria. Ribosomal RNA (rRNA) is the most abundant RNA species, accounting for 80-90% of the RNA in a sample. To reduce sequencing costs, it is necessary to remove ribosomal reads through poly-A enrichment or ribosomal depletion. Bacterial RNA does not contain a poly-A tail, making it difficult to sequence both the nematode and Wolbachia from the same library preparation using standard poly-A selection. Ribosomal depletion can utilize species-specific oligonucleotide probes to remove rRNA through pull-down or degradation methods. While species-specific probes are commercially available for many commonly studied model organisms, there are currently limited depletion options for filarial parasites. Here, we performed total RNA sequencing from Brugia malayi containing the Wolbachia symbiont (wBm) and designed ssDNA depletion probes against their rRNA sequences. We compared the total RNA library to poly-A enriched, Terminator 5'-Phosphate-Dependent Exonuclease treated, NEBNext Human/Bacteria rRNA depleted and our custom nematode probe depleted libraries. The custom nematode depletion library had the lowest percentage of ribosomal reads across all methods, with a 300-fold decrease in rRNA when compared to the total RNA library. The nematode depletion libraries also contained the highest percentage of Wolbachia mRNA reads, resulting in a 16-1,000-fold increase in bacterial reads compared to the other enrichment and depletion methods. Finally, we found that the Brugia malayi depletion probes can remove rRNA from the filarial worm Dirofilaria immitis and the majority of rRNA from the more distantly related free living nematode Caenorhabditis elegans. These custom filarial probes will allow for future dual RNA-seq experiments between nematodes and their bacterial symbionts from a single sequencing library.

Selective and Cascade Reporting of Antimicrobial Susceptibility Testing Results and Its Impact on Antimicrobial Resistance Surveillance-National Healthcare Safety Network, April 2020 to March 2021.

Selective or cascade reporting (SR/CR) of antimicrobial susceptibility testing (AST) results is a strategy for antimicrobial stewardship. SR/CR is often achieved by suppressing AST results of secondary drugs in electronic laboratory reports. We assessed the extent of SR/CR and its impact on cumulative antibiograms (CAs) in a large cohort of U.S. hospitals submitting AST data to the CDC's National Healthcare Safety Network (NHSN) through electronic data exchange. The NHSN calls for hospitals to extract AST data from their electronic systems. We analyzed the AST reported for Escherichia coli (blood and urine) and Staphylococcus aureus (blood and lower respiratory tract [LRT]) isolates from April 2020 to March 2021, used AST reporting patterns to assign SR/CR reporting status for hospitals, and compared their CAs. Sensitivity analyses were done to account for those potentially extracted complete data. At least 35% and 41% of the hospitals had AST data that were suppressed in more than 20% blood isolates for E. coli and S. aureus isolates, respectively. At least 63% (blood) and 50% (urine) routinely reported ciprofloxacin or levofloxacin for E. coli isolates; and 60% (blood) and 59% (LRT) routinely reported vancomycin for S. aureus isolates. The distribution of CAs for many agents differed between high SR/CR and low- or non-SR/CR hospitals. Hospitals struggled to obtain complete AST data through electronic data exchange because of data suppression. Use of SR/CR can bias CAs if incomplete data are used. Technical solutions are needed for extracting complete AST results for public health surveillance. IMPORTANCE This study is the first to assess the extent of using selective and/or cascade antimicrobial susceptibility reporting for antimicrobial stewardship among U.S. hospitals and its impact on cumulative antibiograms in the context of electronic data exchange for national antimicrobial resistance surveillance.

Radiation Exposure Among Orthopaedic Trauma Surgeons: Deconstructing Commonly Held Myths and Misperceptions.

OBJECTIVES: To review and evaluate the validity of common perceptions and practices regarding radiation safety in orthopaedic trauma. DESIGN: Retrospective study. SETTING: Level 1 trauma center. SUBJECTS: N/A. INTERVENTION: The intervention involved personal protective equipment. MAIN OUTCOME MEASUREMENTS: The main outcome measurements included radiation dose estimates. RESULTS: Surgeon radiation exposure estimates performed at the level of the thyroid, chest, and pelvis demonstrate an estimated total annual exposure of 1521 mR, 2452 mR, and 1129 mR, respectively. In all cases, wearing lead provides a significant reduction (90% or better) in the amount of radiation exposure (in both radiation risk and levels of radiation reaching the body) received by the surgeon. Surgeons are inadequately protected from radiation exposure with noncircumferential lead. The commonly accepted notion that there is negligible exposure when standing greater than 6 feet from the radiation source is misleading, particularly when cumulative exposure is considered. Finally, we demonstrated that trauma surgeons specializing in pelvis and acetabular fracture care are at an increased risk of exposure to potentially dangerous levels of radiation, given the amount of radiation required for their caseload. CONCLUSION: Common myths and misperceptions regarding radiation in orthopaedic trauma are unfounded. Proper use of circumferential personal protective equipment is critical in preventing excess radiation exposure.

Comparison of reamed long and short intramedullary nail constructs in unstable intertrochanteric femur fractures: A biomechanical study.

OBJECTIVES: There is no definitive evidence to guide clinicians in their decision-making for implant choice regarding long or short intramedullary nails for unstable fracture patterns. Historically short nails were associated with higher rates of perisprothetic fractures which seem to have improved with newer designs. Long intramedullary nails have higher blood loss and time under anesthesia. The purpose of this study was to assess stability of long and short intramedullary nail constructs in unstable intertrochanteric fracture patterns to better elucidate if unstable intertrochanteric fractures are amenable to treatment with short intramedullary nails. METHODS: This study utilized composite model femurs which were assigned to either a comminuted or reverse obliquity fracture pattern, then subsequently assigned to implantation with either a long or short intramedullary nail. All the samples were reamed to the level of the distal femur and instrumented with the appropriate nail. Axial and torsional stiffness as well as axial load to failure values were determined using a servohydraulic loading system. RESULTS: Short nail constructs exhibited significantly greater axial stiffness in A1 fractures and torsional stiffness in A3 fractures when compared with long nails. There was no significant difference between axial load to failure between long nails and short nails. DISCUSSION: We found no significant difference in axial load to failure values between long and short intramedullary nail fixation in 2 unstable intertrochanteric fracture patterns in a composite femur model. Short nails exhibited greater stiffness in axial loads in the A1 pattern and torsional stiffness in the A3 pattern. This suggests short or long intramedullary nails could be appropriately employed for fixation of unstable intertrochanteric hip fracture patterns.

Percutaneous Fixation of Calcaneal Tuberosity Avulsion Fracture.

There are little data published regarding percutaneous fixation of calcaneal tuberosity avulsion fractures, but tongue-type calcaneal fracture literature can be extrapolated to these injuries because they can be considered the extra-articular form of a tongue-type calcaneus fracture. Both injuries involve similar considerations regarding skin compromise and need for urgent management with similar percutaneous techniques to minimize further soft-tissue injury. Percutaneous fixation of tongue-type calcaneus fractures was first reported by Weshues and Gissane in their description of the Essex Lopresti maneuver as an alternative to open approaches to minimize the risk of soft-tissue complications and flap necrosis and provide a means of improving reductions in smokers and diabetics who may not otherwise be good operative candidates.

Irrigation and Debridement of an Open Ankle Fracture With Open Reduction and Internal Fixation and Syndesmotic Fixation Using a Suture Button Device.

Ankle fractures are among the most common surgically treated fractures. The incidence of syndesmotic injury in ankle fractures is 13%-20%. The goal of syndesmotic fixation is a stable, symmetric ankle joint. Missing or poorly reducing a syndesmotic injury can result in diminished function and tibiotalar arthritis. Recently, a suture button-type device has been used instead of the traditional trans-syndesmotic screw-type fixation. This case-based video demonstrates a technique for using suture button-type devices to repair syndesmotic ankle injuries and presents the data regarding the outcomes of this novel technique.

Preoperative Planning for Percutaneous Transsacral, Transiliac Screws.

Percutaneous transsacral, transiliac screw placement is a well-described, well-established management option for unstable posterior pelvic ring injuries. Safe and effective placement of these screws relies on extensive preoperative planning and scrutiny of the preoperative images. Malpositioning of the implants risks injury to the surrounding neurovascular structures. We present our methods for preoperative templating for safe placement of transsacral, transiliac screws.

Distal Clavicle Fractures: Open Reduction and Internal Fixation With a Hook Plate.

Displaced distal clavicle fractures pose unique challenges because of their propensity for instability. In particular, type II fracture patterns are associated with high rates of nonunion with nonoperative management; therefore, surgical fixation is often recommended. Hook plate fixation has demonstrated reliably high rates of osseous union with good functional outcomes. We present our surgical technique and rationale for using a hook plate in the setting of an unstable distal clavicle fracture.

Spatial distribution of leprosy in India: an ecological study.

BACKGROUND: As leprosy elimination becomes an increasingly realistic goal, it is essential to determine the factors that contribute to its persistence. We evaluate social and economic factors as predictors of leprosy annual new case detection rates within India, where the majority of leprosy cases occur. METHODS: We used correlation and linear mixed effect regressions to assess whether poverty, illiteracy, nighttime satellite radiance (an index of development), and other covariates can explain district-wise annual new case detection rate and Grade 2 disability diagnoses. RESULTS: We find only weak evidence of an association between poverty and annual new case detection rates at the district level, though illiteracy and satellite radiance are statistically significant predictors of leprosy at the district level. We find no evidence of rapid decline over the period 2008-2015 in either new case detection or new Grade 2 disability. CONCLUSIONS: Our findings suggest a somewhat higher rate of leprosy detection, on average, in poorer districts; the overall effect is weak. The divide between leprosy case detection and true incidence of clinical leprosy complicates these results, particularly given that the detection rate is likely disproportionately lower in impoverished settings. Additional information is needed to distinguish the determinants of leprosy case detection and transmission during the elimination epoch.

ORIF Patella Fracture With a Tension Band Construct.

Patellar fractures can occur as a result of direct or indirect injuries. Indirect injury is more common and occurs when the patella fails in tension when the force exerted by the extensor mechanism exceeds that of the bone. Common mechanism of indirect injury is rapid knee flexion with fully contracted quadriceps muscle. Treatment with a tension band construct is indicated for transverse patella fractures without significant comminution. This can be performed with 18-gauge wire and either 2 parallel, longitudinally oriented cannulated screws or 2 Kirschner wires. Biomechanical studies have shown higher load to failure when performed with cannulated screws. We presented our technique for management of a transverse patella fracture with disrupted extensor mechanism using tension banding technique with cannulated screws.

Short-term leprosy forecasting from an expert opinion survey.

We conducted an expert survey of leprosy (Hansen's Disease) and neglected tropical disease experts in February 2016. Experts were asked to forecast the next year of reported cases for the world, for the top three countries, and for selected states and territories of India. A total of 103 respondents answered at least one forecasting question. We elicited lower and upper confidence bounds. Comparing these results to regression and exponential smoothing, we found no evidence that any forecasting method outperformed the others. We found evidence that experts who believed it was more likely to achieve global interruption of transmission goals and disability reduction goals had higher error scores for India and Indonesia, but lower for Brazil. Even for a disease whose epidemiology changes on a slow time scale, forecasting exercises such as we conducted are simple and practical. We believe they can be used on a routine basis in public health.

Correction: Short-term leprosy forecasting from an expert opinion survey.

[This corrects the article DOI: 10.1371/journal.pone.0182245.].

Variation in Optimal Sagittal Alignment of the Femoral Component in Total Knee Arthroplasty.

Accurate sagittal alignment of the femoral component in total knee arthroplasty is crucial for prosthesis longevity, improved function, and patient satisfaction. However, there is variation in the techniques used to attain optimal sagittal femoral component placement in total knee arthroplasty. Femoral component flexion in imageless navigation is based on the mechanical axis rather than the distal femoral anatomy, and there is significant variability in the anatomy of the distal femur. The purpose of this study was to accurately determine the mean distal femoral flexion angle of a representative population and whether variability of the distal femoral flexion angle correlates with race, femur length, or radius of curvature. The mean degree of distal femoral flexion was determined by assessing distal femoral anatomy on computed tomography scans of paired femurs of 1235 patients without evidence of previous fracture, deformity, or surgical implants. The mean±SD distal femoral flexion angle was 2.90°±1.52°, with 80.2% of knees within 3°±2°. Therefore, placing the component in 3° of flexion from the mechanical axis would attain a satisfactory position in most cases. However, further analysis of the patient data revealed 11.4% of Asians, 7.3% of African Americans, and 8.3% of whites had a distal femoral flexion angle greater than 5°. Additionally, the data revealed a moderately strong negative correlation between the distal femoral flexion and the overall radius of curvature of the femur. This preliminary study highlights the need for improved methods for selecting femoral component position in the sagittal plane when using navigation for total knee arthroplasty. [Orthopedics. 2017; 40(2):102-106.].

Proceedings from Heart Rhythm Society's emerging technologies forum, Boston, MA, May 12, 2015.

Physicians are in an excellent position to significantly contribute to medical device innovation, but the process of bringing an idea to the bedside is complex. To begin to address these perceived barriers, the Heart Rhythm Society convened a forum of stakeholders in medical device innovation in conjunction with the 2015 Heart Rhythm Society Annual Scientific Sessions. The forum facilitated open discussion on medical device innovation, including obstacles to physician involvement and possible solutions. This report is based on the themes that emerged. First, physician innovators must take an organized approach to identifying unmet clinical needs and potential solutions. Second, extensive funds, usually secured through solicitation for investment, are often required to achieve meaningful progress, developing an idea into a device. Third, planning for regulatory requirements of the US Food and Drug Administration and Centers for Medicare & Medicaid Services is essential. In addition to these issues, intellectual property and overall trends in health care, including international markets, are critically relevant considerations for the physician innovator. Importantly, there are a number of ways in which professional societies can assist physician innovators to navigate the complex medical device innovation landscape, bring clinically meaningful devices to market more quickly, and ultimately improve patient care. These efforts include facilitating interaction between potential collaborators through scientific meetings and other gatherings; collecting, evaluating, and disseminating state-of-the-art scientific information; and representing the interests of members in interactions with regulators and policymakers.