Socioeconomic Status Affects Postoperative Time to Union in Pediatric Patients with a Surgically Treated Fracture.

Fractures account for 10% to 25% of all pediatric injuries, and surgical treatment is common. In such cases, postoperative healing can be affected by a number of factors, including those related to socioeconomic status (SES). The purpose of this study was to investigate the relationship between time to fracture union and SES, which was measured with use of the median household income (MHI) and Child Opportunity Index (COI). Methods: A retrospective review was conducted of pediatric patients with a long-bone fracture that had been surgically treated at a Level-I pediatric trauma center between January 2010 and June 2020. Demographic and relevant medical data were collected. Patients were sorted into union and nonunion groups. The ZIP code of each patient was collected and the MHI and COI of that ZIP code were identified. Income brackets were created in increments of $10,000 ranging from $20,000 to $100,000, with an additional category of >$100,000, and patients were sorted into these groups according to MHI. Comparisons among the income groups and among the union status groups were conducted for each of the collected variables. A multiple regression analysis was utilized to determine the independent effect of each variable on time to union. Results: A total of 395 patients were included in the final sample, of whom 51% identified as Hispanic. Patients in the union group had a higher mean COI and MHI. Nonunion occurred in only 8 patients. Patients who achieved fracture union in ≤4 months had a significantly higher mean COI and MHI. When controlling for other demographic variables, the time to union increased by a mean of 9.6 days for every $10,000 decrease in MHI and increased by a mean of 6.8 days for every 10-unit decrease in the COI. Conclusions: The present study is the first, to our knowledge, to investigate the relationship between SES and time to fracture union in pediatric patients. When controlling for other demographic factors, we found a significant relationship between SES and time to union in pediatric patients with a surgically treated fracture. Further investigations of the relationship between SES and time to union in pediatric patients are needed to determine potential mechanisms for this relationship. Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

14th century Yersinia pestis genomes support emergence of pestis secunda within Europe.

Pestis secunda (1356-1366 CE) is the first of a series of plague outbreaks in Europe that followed the Black Death (1346-1353 CE). Collectively this period is called the Second Pandemic. From a genomic perspective, the majority of post-Black Death strains of Yersinia pestis thus far identified in Europe display diversity accumulated over a period of centuries that form a terminal sub-branch of the Y. pestis phylogeny. It has been debated if these strains arose from local evolution of Y. pestis or if the disease was repeatedly reintroduced from an external source. Plague lineages descended from the pestis secunda, however, are thought to have persisted in non-human reservoirs outside Europe, where they eventually gave rise to the Third Pandemic (19th and 20th centuries). Resolution of competing hypotheses on the origins of the many post-Black Death outbreaks has been hindered in part by the low representation of Y. pestis genomes in archaeological specimens, especially for the pestis secunda. Here we report on five individuals from Germany that were infected with lineages of plague associated with the pestis secunda. For the two genomes of high coverage, one groups within the known diversity of genotypes associated with the pestis secunda, while the second carries an ancestral genotype that places it earlier. Through consideration of historical sources that explore first documentation of the pandemic in today's Central Germany, we argue that these data provide robust evidence to support a post-Black Death evolution of the pathogen within Europe rather than a re-introduction from outside. Additionally, we demonstrate retrievability of Y. pestis DNA in post-cranial remains and highlight the importance of hypothesis-free pathogen screening approaches in evaluations of archaeological samples.

From Esthetic Medicine to Optimizing Reconstructive Outcome: A Feasibility Trial on Secondary Refinement of Fasciocutaneous Anterolateral Thigh Flaps with Cryolipolysis.

BACKGROUND: Free adipocutaneous anterolateral thigh (ALT) flaps have evolved as workhorse flaps to reconstruct complex, multicompound defects. While coverage is safely achieved, flaps may remain bulky. As a standard of care, flaps are refined with liposuction, partial excision, or combination of both. Cryolipolysis is widely used for fat reduction in esthetic medicine. This pilot comparative study analyses whether cryolipolysis may serve as a safe alternative method to effectively reduce volume in fasciocutaneous flaps. Moreover, patients' satisfaction with the procedure is evaluated. METHODS: In this single-center, retrospective, interventional comparative cohort study, 10 patients with free subfascial ALT flaps for distal extremity reconstruction underwent cryolipolysis (60 minutes, -9°C). Circumference of the extremities and subcutaneous fat thickness were determined before (T1) and 12 weeks (T2) after cryolipolysis. Patient satisfaction was evaluated with a questionnaire of Likert's scale questions. Duration of hospital stay, intervention time, costs, and possible complications were analyzed and compared with surgical flap contouring (n = 12). RESULTS: All patients undergoing cryolipolysis were male, with a median age of 52 years without arterial disease-like state or deep vein thrombosis (DVT). At T2, a significant reduction of circumference of 1.8 ± 0.9 cm (p < 0.001) and subcutaneous fat layer of 7.7 ± 3.0 mm (p < 0.0001) was recorded. Overall, 90% of the patients were satisfied with the result. Cryolipolysis was well tolerated. One patient developed a second-degree frostbite which healed without further intervention. Cryolipolysis proofed to be as safe as surgical flap contouring. Hospital stay was significantly shorter (p < 0.01) and personal resources were spared when flap contouring was performed with cryolipolysis. CONCLUSION: This is a novel application of evolving body-contouring cryolipolysis from esthetic medicine into optimizing outcomes in reconstructive surgery. Cryolipolysis has been shown to be relatively safe and effective to reduce ALT's volume with high patients' satisfaction. This successful pilot study encourages further investigation with a prospective randomized control trial.

Genetic insights into the social organization of Neanderthals.

Genomic analyses of Neanderthals have previously provided insights into their population history and relationship to modern humans1-8, but the social organization of Neanderthal communities remains poorly understood. Here we present genetic data for 13 Neanderthals from two Middle Palaeolithic sites in the Altai Mountains of southern Siberia: 11 from Chagyrskaya Cave9,10 and 2 from Okladnikov Cave11-making this one of the largest genetic studies of a Neanderthal population to date. We used hybridization capture to obtain genome-wide nuclear data, as well as mitochondrial and Y-chromosome sequences. Some Chagyrskaya individuals were closely related, including a father-daughter pair and a pair of second-degree relatives, indicating that at least some of the individuals lived at the same time. Up to one-third of these individuals' genomes had long segments of homozygosity, suggesting that the Chagyrskaya Neanderthals were part of a small community. In addition, the Y-chromosome diversity is an order of magnitude lower than the mitochondrial diversity, a pattern that we found is best explained by female migration between communities. Thus, the genetic data presented here provide a detailed documentation of the social organization of an isolated Neanderthal community at the easternmost extent of their known range.

The 8-item Modified Frailty Index Is an Effective Risk Assessment Tool in Anterior Cervical Decompression and Fusion.

STUDY DESIGN: Case-control study; Level of evidence, 3. OBJECTIVE: Anterior cervical discectomy and fusion (ACDF) is one of the most common procedures for cervical diseases often with reliable outcomes. However, morbidity rates can be as high as 19.3% so appropriate patient selection and risk stratification is imperative. Our modified frailty index (MFI) predicts postoperative complications after other orthopaedic procedures. We hypothesized that this index would predict complications in a large cohort of ACDF patients. METHODS: We reviewed the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database, including patients who underwent ACDF from 2015-2020. An 8-item MFI score was calculated for each patient. We recorded 30-days postoperative complications, readmission, and reoperation rates, adjusting for baseline features using standard multivariate regression. This project was approved of by the University of Texas Health Science Center Institutional Review Board and an IRB exception was granted. RESULTS: We identified 17 662 ACDF cases. Patients with MFI of 5 or greater had a 37.53 times increased odds of incurring postoperative complications compared to patients with MFI of 0 (P < .001) even when age, sex, race, and ethnicity were controlled for. Specifically, life-threatening Clavien-Dindo IV complications, as well as wound, cardiac, renal, and pulmonary complications were significantly increased in patients with an MFI of 5 or greater. Also, as MFI increased from 1-2 to 3-4 to 5 or greater, the odds of readmission increased from 1.36 to 2.31 to 5.42 times (P < .001) and odds of reoperation from 1.19 (P = .185) to 2.3 to 6.54 times (P < .001). Frailty was still associated with increased complications, readmission, and reoperation after controlling for demographic data, including age, as well as operative time and length of stay. CONCLUSION: Frailty is highly predictive of postoperative complications, readmission, and reoperation following ACDF. Employing a simple frailty evaluation can guide surgical decision-making and patient counseling for cervical disease.

Use of Clindamycin for Necrotizing Soft Tissue Infection Decreases Amputation Rate.

OBJECTIVE: To identify the impact of clindamycin use on mortality and amputation rates in patients with necrotizing fasciitis. DESIGN: Retrospective review. SETTING: Level 1 trauma center, single-center study. PATIENTS/PARTICIPANTS: All patients from 2008 to 2019 with a diagnosis of necrotizing fasciitis. One hundred ninety patients were included in statistical analysis. INTERVENTION: Use of clindamycin in the initial antibiotic regimen in the treatment of necrotizing soft tissue infection. MAIN OUTCOME MEASUREMENTS: Amputation and mortality rates. RESULTS: Patients who received clindamycin had 2.92 times reduced odds of having an amputation when compared with their counterparts, even when American Society of Anesthesiologist scores, comorbidities, smoking, drug use, alcohol consumption, race, ethnicity, sex, and age were controlled for and regardless of other antibiotics started (P = 0.015). There was no significant difference in mortality rate between those patients who did and did not receive clindamycin as part of their initial antibiotic regimen (8.3% vs. 11.6%, respectively; P = 0.453). CONCLUSION: The use of clindamycin in the initial antibiotic regimen for treatment of NSTI was shown to significantly decrease rates of amputation but not mortality. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

[Postoperative monitoring of free muscle flaps using perforator-based adipocutaneous skin paddles: economy, quality of care and aesthetics]. / Postoperatives Monitoring freier Muskellappenplastiken mittels perforatorbasierten adipokutanen Monitorinseln: Ökonomie, Versorgungsqualität und Ästhetik.

INTRODUCTION: Besides fasciocutaneous workhorse flaps, free muscle flaps for the reconstruction of large soft tissue defects are well-established standard microsurgical procedures. Random-pattern adipocutaneous skin paddles are often included for postoperative perfusion monitoring of the muscle flap. At our institution, both conventional broad-based and perforator-based adipocutaneous skin paddles are used. While conventional skin paddles have to be removed during a second operation, perforator-based skin paddles can be removed at the bedside by ligature. The present study aims to compare economic aspects, quality of care and aesthetic results of perforator-based versus conventional adipocutaneous skin paddles after free muscle flap transfer. METHODS: 102 patients treated between August 2014 and July 2016 were identified and included in a retrospective data analysis. Patients with perforator-based skin paddles (group A) were compared with a population of patients with conventional skin paddles (group B). Patient characteristics, procedural characteristics, economic data and aesthetic results were compared between both groups. RESULTS: Perforator-based skin paddles were raised in 72 patients (group A, 71 %), and conventional skin paddles were raised in the remaining 30 patients (group B, 29 %). Patient, defect, and flap characteristics were comparable in both groups. Operating times tended to be shorter in group B. Skin paddle removal was performed significantly earlier in group A (p < 0.01). Both overall and post-reconstructive length of hospital stay were significantly shorter in group A (p = 0.03; p < 0.01). Also, personnel and material resources were saved and more satisfactory aesthetic results were achieved in group A. CONCLUSION: Perforator-based monitor islands can help avoid secondary operations that would otherwise be necessary to remove monitoring skin paddles. Thus, the inpatient length of stay can be reduced while sparing material and human resources.

Microstratigraphic preservation of ancient faunal and hominin DNA in Pleistocene cave sediments.

Ancient DNA recovered from Pleistocene sediments represents a rich resource for the study of past hominin and environmental diversity. However, little is known about how DNA is preserved in sediments and the extent to which it may be translocated between archaeological strata. Here, we investigate DNA preservation in 47 blocks of resin-impregnated archaeological sediment collected over the last four decades for micromorphological analyses at 13 prehistoric sites in Europe, Asia, Africa, and North America and show that such blocks can preserve DNA of hominins and other mammals. Extensive microsampling of sediment blocks from Denisova Cave in the Altai Mountains reveals that the taxonomic composition of mammalian DNA differs drastically at the millimeter-scale and that DNA is concentrated in small particles, especially in fragments of bone and feces (coprolites), suggesting that these are substantial sources of DNA in sediments. Three microsamples taken in close proximity in one of the blocks yielded Neanderthal DNA from at least two male individuals closely related to Denisova 5, a Neanderthal toe bone previously recovered from the same layer. Our work indicates that DNA can remain stably localized in sediments over time and provides a means of linking genetic information to the archaeological and ecological records on a microstratigraphic scale.

A Retrospective Comparative Functional and Aesthetic Outcome Study of Muscle versus Cutaneous Free Flaps for Distal Upper Extremity Reconstruction.

BACKGROUND: Function and cosmesis are crucial in upper extremity reconstruction. Yet, there persists a lack of outcome evaluations, particularly regarding differences between free flap types. METHODS: In a single-center retrospective analysis, outcomes were compared between patients with cutaneous or muscle free flaps for distal upper extremity reconstruction between 2008 and 2018. The Disabilities of Arm, Shoulder and Hand -Score, Michigan-Hand (MHQ), and Short Form 36 Health Survey (SF-36) Questionnaires were assessed, motor function was quantified, and self-reported measures of cosmesis were compared, including the Vancouver Scar-Scale (VSS), MHQ aesthetics-subscale (MAS), and Moscona's cosmetic validation-score (CVS). RESULTS: One-hundred forty-one cases were identified, with a shift toward cutaneous flaps over the study period. Muscle flaps were used for larger defects (251 vs. 142 cm2, p = 0.008). Losses, thromboses, and donor-site complications were equally distributed. Partial necroses were more frequent in muscle flaps (11 vs. 1%, p = 0.015). Seventy patients with 53 cutaneous versus 17 muscle flaps were reexamined. There was no difference in the timing of flap coverage (after 16 vs. 15 days, p = 0.79), number of preceding (2 vs. 1.7, p = 0.95), or subsequent operations (19/53 vs. 5/17, p = 0.77). Patients with cutaneous flaps showed higher grip strength (25 vs. 17 kg, p = 0.046) and reported better hand function (MHQ: 58 vs. 47, p = 0.044) and general health (SF-36: 70 vs. 61, p = 0.040), as well as more favorable appearance (MAS: 71 vs. 57, p = 0.044, CVS: 77 vs. 72, p = 0.048), and scar burden (VSS: 0 vs. 3, p < 0.001). CONCLUSION: Cutaneous flaps yielded better motor function, self-perceived cosmesis, patient satisfaction, and quality of life in our cohort of distal upper extremity reconstructions.

A single-center retrospective comparison of Duplex ultrasonography versus audible Doppler regarding anterolateral thigh perforator flap harvest and operative times.

INTRODUCTION: We reported on the superiority of preoperative Duplex mapping ("Duplex") over audible Dopplers ("Doppler") in anterolateral thigh perforator (ALT) free flaps for upper extremity reconstruction. To corroborate our findings on a larger cohort, we conducted this present study focusing on surgical efficiency and patient safety. METHODS: 150 consecutive ALT free flaps were divided into 65 cases of preoperative Duplex versus 85 Doppler controls. We first compared patient demographics, operative details, and defect and flap characteristics. We then assessed group differences in the number and course of perforators pursued intraoperatively, flap harvest and operative times, and donor-site complications. Additionally, the impact of the training level of the primary microsurgeon was evaluated. RESULTS: Cases and controls were comparable regarding age (p = .48), sex (p = .81), ASA class (p = .48), and BMI (p = .90). Duplex was associated with an increased likelihood of raising flaps on one single dominant perforator of purely septal course and significant reductions of flap harvest (68 ± 10 min, p < .0001) and operative times (74 ± 16 min, p < .0001), regardless of the experience of the primary microsurgeon. There were strong negative linear correlations between preoperative Duplex and both the flap harvest and operative times (p < .0001). Additionally, while there was no effect on the emergency take-back rate (OR = 1.3, p = .60), revisions were significantly less likely among duplexed patients (OR = 0.15, p = .04). CONCLUSIONS: Preoperative Duplex is associated with a significant reduction in ALT free flap harvest and overall operative times, as well as donor-site revisions as opposed to Doppler planning, regardless of the training level of the primary microsurgeon.

The impact of closed incisional negative pressure therapy on anterior lateral thigh flap donor site healing and scarring: A retrospective case-control study.

BACKGROUND: The objective of this study was to investigate whether closed incisional negative pressure therapy (cINPT) is suitable to improve anterior lateral thigh (ALT) flap donor site healing and scarring. METHODS: We identified 271 ALT free flaps of widths between 7 and 9 cm and primary donor site closure performed between January 2012 to December 2019. Patients were divided into cases of cINPT versus controls without cINPT as part of this retrospective case-control review. We compared the incidences of postoperative donor site complications (wound dehiscence, infection, seroma, hematoma) and the degree of scarring severity using the Vancouver Scar Scale (VSS) and the Patient and Observer Scar Assessment Scales (POSAS). RESULTS: A total of 106 ALT donor sites received cINPT (39%), whereas the remaining 165 donor sites received conventional dressings (61%). The distribution of gender, age, body mass index, comorbidities, and mean flap sizes were comparable between both groups. The occurrence of surgical wound dehiscence was significantly lower in the cINPT group (2.8%), when compared to controls (9.0%) (p = 0.04). Furthermore, the mean length of postoperative hospital stay was significantly shorter in the cINPT group (19 ± 8 days versus 21 ± 11 days; p = 0.03). CINPT was associated with a more favorable donor site scar quality when assessed by VSS (p = 0.03) and POSAS (p = 0.002). CONCLUSION: The use of cINPT was associated with significantly less ALT donor site complications and superior scar quality accelerating patients' postoperative recovery.

Pleistocene sediment DNA reveals hominin and faunal turnovers at Denisova Cave.

Denisova Cave in southern Siberia is the type locality of the Denisovans, an archaic hominin group who were related to Neanderthals1-4. The dozen hominin remains recovered from the deposits also include Neanderthals5,6 and the child of a Neanderthal and a Denisovan7, which suggests that Denisova Cave was a contact zone between these archaic hominins. However, uncertainties persist about the order in which these groups appeared at the site, the timing and environmental context of hominin occupation, and the association of particular hominin groups with archaeological assemblages5,8-11. Here we report the analysis of DNA from 728 sediment samples that were collected in a grid-like manner from layers dating to the Pleistocene epoch. We retrieved ancient faunal and hominin mitochondrial (mt)DNA from 685 and 175 samples, respectively. The earliest evidence for hominin mtDNA is of Denisovans, and is associated with early Middle Palaeolithic stone tools that were deposited approximately 250,000 to 170,000 years ago; Neanderthal mtDNA first appears towards the end of this period. We detect a turnover in the mtDNA of Denisovans that coincides with changes in the composition of faunal mtDNA, and evidence that Denisovans and Neanderthals occupied the site repeatedly-possibly until, or after, the onset of the Initial Upper Palaeolithic at least 45,000 years ago, when modern human mtDNA is first recorded in the sediments.

[Evaluation of secondary refinement procedures following free microvascular tissue reconstruction of the upper extremity]. / Evaluation von Sekundäreingriffen nach mikrochirurgischer Lappentransplantation zur Rekonstruktion der oberen Extremität.

BACKGROUND: The primary cosmetic and functional outcome following successful upper limb salvage using free tissue transfer can often be unfavourable, which may motivate patients to undergo secondary procedures. In this study, we sought to identify predictors for secondary procedures and to analyse the type and number of these procedures. PATIENTS AND METHODS: Patients who underwent free tissue transfer to the upper extremity between 2010 and 2017 were included in a retrospective cohort study: patients with secondary procedures to optimise the functional and aesthetic flap design (S cohort) vs. control cohort (C cohort). A multivariate regression analysis was used to identify predictors for secondary procedures. RESULTS: One hundred and twenty-eight patients were included in the study (S cohort 36, C cohort 92). All in all, 56 secondary refinement procedures were performed in a mean of eight months after the initial free flap reconstruction. Most of the defects in the S cohort were localised at the hand (53 %), and upper limb salvage was mostly accomplished by fasciocutaneous and adipocutaneous free flaps (S cohort 89 %). The most frequently performed secondary refinement procedures were direct partial flap excision (61 %), followed by liposuction (16 %) and the combination of both (17 %). Furthermore, 64 % of the secondary refinement procedures from the S cohort were combined with further surgical interventions to improve hand function, e. g. tenolysis and arthrolysis. Patients with defects of the hand received secondary procedures 2.4 times more frequently (p = 0.05). Also, patients with a good general health condition (ASA 1 and 2) were six times more likely to undergo a secondary procedure (p = 0.03). CONCLUSION: Secondary procedures are safe and frequently requested by patients following successful free flap upper limb salvage. In particular, this applies to patients who are in a good health condition and with free flaps to the hand. Therefore, we recommend the implementation of secondary refinement procedures in the reconstructive plan to increase patient compliance and satisfaction.

Unearthing Neanderthal population history using nuclear and mitochondrial DNA from cave sediments.

Bones and teeth are important sources of Pleistocene hominin DNA, but are rarely recovered at archaeological sites. Mitochondrial DNA (mtDNA) has been retrieved from cave sediments but provides limited value for studying population relationships. We therefore developed methods for the enrichment and analysis of nuclear DNA from sediments and applied them to cave deposits in western Europe and southern Siberia dated to between 200,000 and 50,000 years ago. We detected a population replacement in northern Spain about 100,000 years ago, which was accompanied by a turnover of mtDNA. We also identified two radiation events in Neanderthal history during the early part of the Late Pleistocene. Our work lays the ground for studying the population history of ancient hominins from trace amounts of nuclear DNA in sediments.

Initial Upper Palaeolithic humans in Europe had recent Neanderthal ancestry.

Modern humans appeared in Europe by at least 45,000 years ago1-5, but the extent of their interactions with Neanderthals, who disappeared by about 40,000 years ago6, and their relationship to the broader expansion of modern humans outside Africa are poorly understood. Here we present genome-wide data from three individuals dated to between 45,930 and 42,580 years ago from Bacho Kiro Cave, Bulgaria1,2. They are the earliest Late Pleistocene modern humans known to have been recovered in Europe so far, and were found in association with an Initial Upper Palaeolithic artefact assemblage. Unlike two previously studied individuals of similar ages from Romania7 and Siberia8 who did not contribute detectably to later populations, these individuals are more closely related to present-day and ancient populations in East Asia and the Americas than to later west Eurasian populations. This indicates that they belonged to a modern human migration into Europe that was not previously known from the genetic record, and provides evidence that there was at least some continuity between the earliest modern humans in Europe and later people in Eurasia. Moreover, we find that all three individuals had Neanderthal ancestors a few generations back in their family history, confirming that the first European modern humans mixed with Neanderthals and suggesting that such mixing could have been common.

Comparison of pedicled versus free flaps for reconstruction of extensive deep sternal wound defects following cardiac surgery: A retrospective study.

BACKGROUND: Myocutaneous pedicled flaps are the method of choice for sternal reconstruction after deep sternal wound infection (DSWI) following cardiac surgery. We set out to investigate whether free flaps provide a superior alternative for particularly extended sternal defects. METHODS: Between October 2008 and February 2020, 86 patients with DSWI underwent sternal reconstruction with myocutaneous flaps at our institution. Patients were retrospectively grouped into pedicled (A; n = 42) and free flaps (B, n = 44). The objective was to compare operative details, outcome variables, surgical as well as medical complication rates between both groups, retrospectively. Binary logistic regression analysis was applied to determine the effect of increasing defect size on flap necrosis. RESULTS: Rates of partial flap necrosis (>5% of the skin island) were significant higher in pedicled flaps (n = 14), when compared to free flaps (n = 4) (OR: 5.0; 33 vs. 9%; p = .008). Increasing defect size was a significant risk factor for the incidence of partial flap necrosis of pedicled flaps (p = .012), resulting in a significant higher rate of additional surgeries (p = .036). Binary regression model revealed that the relative likelihood of pedicled flap necrosis increased by 2.7% with every extra square-centimeter of defect size. CONCLUSION: To avoid an increased risk of partial flap necrosis, free flaps expand the limits of extensive sternal defect reconstruction with encouragingly low complication rates and proved to be a superior alternative to pedicled flaps in selected patients.

Denisovan ancestry and population history of early East Asians.

We present analyses of the genome of a ~34,000-year-old hominin skull cap discovered in the Salkhit Valley in northeastern Mongolia. We show that this individual was a female member of a modern human population that, following the split between East and West Eurasians, experienced substantial gene flow from West Eurasians. Both she and a 40,000-year-old individual from Tianyuan outside Beijing carried genomic segments of Denisovan ancestry. These segments derive from the same Denisovan admixture event(s) that contributed to present-day mainland Asians but are distinct from the Denisovan DNA segments in present-day Papuans and Aboriginal Australians.

A systematic investigation of human DNA preservation in medieval skeletons.

Ancient DNA (aDNA) analyses necessitate the destructive sampling of archaeological material. Currently, the cochlea, part of the osseous inner ear located inside the petrous pyramid, is the most sought after skeletal element for molecular analyses of ancient humans as it has been shown to yield high amounts of endogenous DNA. However, destructive sampling of the petrous pyramid may not always be possible, particularly in cases where preservation of skeletal morphology is of top priority. To investigate alternatives, we present a survey of human aDNA preservation for each of ten skeletal elements in a skeletal collection from Medieval Germany. Through comparison of human DNA content and quality we confirm best performance of the petrous pyramid and identify seven additional sampling locations across four skeletal elements that yield adequate aDNA for most applications in human palaeogenetics. Our study provides a better perspective on DNA preservation across the human skeleton and takes a further step toward the more responsible use of ancient materials in human aDNA studies.

Manual and automated preparation of single-stranded DNA libraries for the sequencing of DNA from ancient biological remains and other sources of highly degraded DNA.

It has been shown that highly fragmented DNA is most efficiently converted into DNA libraries for sequencing if both strands of the DNA fragments are processed independently. We present an updated protocol for library preparation from single-stranded DNA, which is based on the splinted ligation of an adapter oligonucleotide to the 3' ends of single DNA strands, the synthesis of a complementary strand using a DNA polymerase and the addition of a 5' adapter via blunt-end ligation. The efficiency of library preparation is determined individually for each sample using a spike-in oligonucleotide. The whole workflow, including library preparation, quantification and amplification, requires two work days for up to 16 libraries. Alternatively, we provide documentation and electronic protocols enabling automated library preparation of 96 samples in parallel on a Bravo NGS Workstation (Agilent Technologies). After library preparation, molecules with uninformative short inserts (shorter than ~30-35 base pairs) can be removed by polyacrylamide gel electrophoresis if desired.

A comparative study of preoperative color-coded Duplex ultrasonography versus handheld audible Dopplers in ALT flap planning.

INTRODUCTION: The anterior lateral thigh (ALT) flap's vascular variability can lead to complications. Thus, the accuracy of numerous planning modalities has been studied. The clinical relevance of competing mapping methods, however, remains unknown. Therefore, we compared the impact of color-coded Duplex ultrasonography and handheld audible Dopplers on surgical efficacy and flap safety. PATIENTS AND METHODS: Forty-four ALT flaps were included in this comparative retrospective monocentric study. Twelve patients received Duplex scans and 32 flaps were designed using Dopplers only. Patient, defect, and flap characteristics of both groups were analyzed. The effect of either planning method on the primary outcome variables - flap harvest and operative times (HT, OT), course of perforator dissection, incidence of flap loss, emergent re-explorations, and donor-site revisions - was then assessed. RESULTS: Patient, defect, and flap characteristics were comparable between both groups, including flap size (Doppler: 134 ± 73 cm2 , Duplex: 131 ± 65 cm2 , p = .90). There was no flap loss. Emergent re-explorations (Doppler: 4/32, Duplex: 1/12, p = .70) and donor-site revisions (Doppler: 2/32, Duplex: 1/12, p = .81) were equally distributed. Duplex rendered septal perforator dissection 10 times more likely (Chi-Square = 8.9, p = .003, OR = 9.7), reaching 50% (n = 6/12), as opposed to only 9% in the Doppler cohort (n = 3/32). This allowed for highly significant HT and OT reductions of 89 minutes, respectively (p < .01): from 255 and 383 min (Doppler) to 166 and 294 min (Duplex). CONCLUSIONS: Preoperative Duplex significantly reduces harvest and operative times of ALT flaps.