The developmental mechanics of divergent buckling patterns in the chick gut.

Tissue buckling is an increasingly appreciated mode of morphogenesis in the embryo, but it is often unclear how geometric and material parameters are molecularly determined in native developmental contexts to generate diverse functional patterns. Here, we study the link between differential mechanical properties and the morphogenesis of distinct anteroposterior compartments in the intestinal tract-the esophagus, small intestine, and large intestine. These regions originate from a simple, common tube but adopt unique forms. Using measured data from the developing chick gut coupled with a minimal theory and simulations of differential growth, we investigate divergent lumen morphologies along the entire early gut and demonstrate that spatiotemporal geometries, moduli, and growth rates control the segment-specific patterns of mucosal buckling. Primary buckling into wrinkles, folds, and creases along the gut, as well as secondary buckling phenomena, including period-doubling in the foregut and multiscale creasing-wrinkling in the hindgut, are captured and well explained by mechanical models. This study advances our existing knowledge of how identity leads to form in these regions, laying the foundation for future work uncovering the relationship between molecules and mechanics in gut morphological regionalization.

Editorial Commentary: Socioeconomic Disparities in Health Outcomes: The Patient Behind the Procedure.

Equitable delivery of health care, regardless of sex, race, ethnicity, or socioeconomic status (SES), is shown to be generally unsuccessful. The benefits of standardized treatment protocols to increase clinical consistency and efficiency are clear, but risk inferior outcomes if not adapted to account for socioeconomically disadvantaged patients. Underinsured patients face challenges accessing continuous and comprehensive care, even during the post-operative period. However, implementation of individualized patient education in combination of standardized protocols significantly reduces disparities in outcomes. A patient-centered care philosophy is critical. Implementing health literacy, fostering close therapeutic relationships including with physical therapists for post-surgical patients, and ensuring access to follow-up care reduce complications and readmissions.

Parachute Technique for Dermal Allograft Augmentation in Open Gluteal Abductor Repair.

Retracted full-thickness tears of the gluteus medius tendon are a well-recognized cause of disabling weakness and pain that significantly impact patients' quality of life. We present an efficient knotless parachute technique for dermal allograft augmentation in open gluteal abductor tendon repairs. Our technique reinforces the suture-tendon interface by incorporating a robust biological scaffold into a knotless double-row fixation. This approach capitalizes on the increased pressure and contact area achieved between the greater trochanter and the dermal allograft/gluteus medius tendon construct without the prominence of knotted sutures.

Association Between Utilization of Services and Perioperative Outcomes for Lung Cancer Resection.

INTRODUCTION: Lung cancer resection has largely focused on perioperative outcomes (eg, mortality) to benchmark performance. While variations in perioperative outcomes and in utilization of services (eg, ambulatory procedures, hospitalization) have been independently demonstrated, there has been limited evaluation of associations between these outcomes. We evaluated the association between perioperative outcomes and utilization of services to evaluate provider performance across a broader context of care. PATIENTS AND METHODS: This was a retrospective cohort study of patients undergoing lung cancer resection in 2017 to 2019. We utilized hierarchical logistic regression models to determine risk- and reliability-adjusted mortality and risk-adjusted utilization of services, at the hospital-level. We then evaluated utilization of services across quartiles of perioperative mortality. RESULTS: A total of 15,168 patients across 297 hospitals underwent lung cancer resection. Mean risk- and reliability-adjusted 90-day mortality varied between 1.58% (95% CI, 1.54%-1.62%) and 2.74% (95% CI, 2.59%-2.90%) across quartiles. Risk-adjusted utilization of all ambulatory procedures was highest in the best performing (lowest mortality) quartile at 37.7% (95% CI, 33.6%-41.8%). Additionally, risk-adjusted inpatient utilization prior to and after surgery was lowest in the best performing quartile at 15% (95% CI, 13.7%-16.3%) and 19.3% (95% CI, 17.5%-21.0%), respectively. CONCLUSIONS: Hospitals with the lowest perioperative mortality demonstrated trends towards using more outpatient resources prior to surgery, but fewer inpatient services surrounding lung cancer resection. This correlation highlights the importance of incorporating utilization of services in addition to other metrics to profile the efficiency and effectiveness of centers performing lung cancer resection across a broader spectrum of care.

An efficient low cost means of biophysical gene transfection in primary cells.

Efficient, facile gene modification of cells has become an indispensable part of modern molecular biology. For the majority of cell lines and several primary populations, such modifications can be readily performed through a variety of methods. However, many primary cell lines such as stem cells frequently suffer from poor transfection efficiency. Though several physical approaches have been introduced to circumvent these issues, they often require expensive/specialized equipment and/or consumables, utilize substantial cell numbers and often still suffer from poor efficiency. Viral methods are capable of transducing difficult cellular populations, however such methods can be time consuming for large arrays of gene targets, present biohazard concerns, and result in expression of viral proteins; issues of concern for certain experimental approaches. We report here a widely applicable, low-cost (< $100 CAD) method of electroporation, applicable to small (1-10 µl) cell volumes and composed of equipment readily available to the average investigator. Using this system we observe a sixfold increase in transfection efficiency in embryonic stem cell lines compared to commercial devices. Due to efficiency gains and reductions in volume and applied voltage, this process improves the survival of sensitive stem cell populations while reducing reagent requirements for protocols such as Cas9/gRNAs transfections.

Grazing herbivores reduce herbaceous biomass and fire activity across African savannas.

Fire and herbivory interact to alter ecosystems and carbon cycling. In savannas, herbivores can reduce fire activity by removing grass biomass, but the size of these effects and what regulates them remain uncertain. To examine grazing effects on fuels and fire regimes across African savannas, we combined data from herbivore exclosure experiments with remotely sensed data on fire activity and herbivore density. We show that, broadly across African savannas, grazing herbivores substantially reduce both herbaceous biomass and fire activity. The size of these effects was strongly associated with grazing herbivore densities, and surprisingly, was mostly consistent across different environments. A one-zebra increase in herbivore biomass density (~100 kg/km2 of metabolic biomass) resulted in a ~53 kg/ha reduction in standing herbaceous biomass and a ~0.43 percentage point reduction in burned area. Our results indicate that fire models can be improved by incorporating grazing effects on grass biomass.

Traceable Calibration of Atmospheric Oxidized Mercury Measurements.

Most previous measurements of oxidized mercury were collected using a method now known to be biased low. In this study, a dual-channel system with an oxidized mercury detection limit of 6-12 pg m-3 was deployed alongside a permeation tube-based automated calibrator at a mountain top site in Steamboat Springs Colorado, USA, in 2021 and 2022. Permeation tubes containing elemental mercury and mercury halides were characterized via an International System of Units (SI)-traceable gravimetric method and gas chromatography/mass spectrometry before deployment in the calibrator. The dual-channel system recovered 97 ± 4 and 100 ± 8% (±standard deviation) of injected elemental mercury and HgBr2, respectively. Total Hg permeation rates and Hg speciation from the gravimetric method, the chromatography system, the dual-channel system, and an independent SI-traceable measurement method performed at the Jozef Stefan Institute laboratory were all comparable within the respective uncertainties of each method. These are the first measurements of oxidized mercury at low environmental concentrations that have been verified against an SI-traceable calibration system in field conditions while sampling ambient air, and they show that accurate, routinely calibrated oxidized mercury measurements are achievable.

Patterning and folding of intestinal villi by active mesenchymal dewetting.

Tissue folds are structural motifs critical to organ function. In the intestine, bending of a flat epithelium into a periodic pattern of folds gives rise to villi, finger-like protrusions that enable nutrient absorption. However, the molecular and mechanical processes driving villus morphogenesis remain unclear. Here, we identify an active mechanical mechanism that simultaneously patterns and folds the intestinal epithelium to initiate villus formation. At the cellular level, we find that PDGFRA+ subepithelial mesenchymal cells generate myosin II-dependent forces sufficient to produce patterned curvature in neighboring tissue interfaces. This symmetry-breaking process requires altered cell and extracellular matrix interactions that are enabled by matrix metalloproteinase-mediated tissue fluidization. Computational models, together with in vitro and in vivo experiments, revealed that these cellular features manifest at the tissue level as differences in interfacial tensions that promote mesenchymal aggregation and interface bending through a process analogous to the active dewetting of a thin liquid film.

The cranial and postcranial morphology of Hutchemys rememdium and its impact on the phylogenetic relationships of Plastomenidae (Testudinata, Trionychidae).

Hutchemys rememdium is a poorly understood softshell turtle (Trionychidae) from the mid Paleocene of the Williston Basin of North America previously known only from postcranial remains. A particularly rich collection of previously undescribed material from the Tiffanian 4 North American Land Mammal Age (NALMA) of North Dakota is here presented consisting of numerous shells that document new variation, some non-shell postcrania, and cranial remains, which are described based on 3D models extracted from micro-CT data. Although the observed shell variation weakens previously noted differences with the younger species Hutchemys arctochelys from the Clarkforkian NALMA, the two taxa are still recognized as distinct. Parsimony and Bayesian phylogenetic analyses reaffirm the previously challenged placement of Hutchemys rememdium within the clade Plastomenidae, mostly based on novel observations of cranial characters made possible by the new material and the micro-CT data. The new topology supports the notion that the well-ossified plastron of plastomenids originated twice in parallel near the Cretaceous/Paleogene boundary, once in the Hutchemys lineage and once in the Gilmoremys/Plastomenus lineage. Hutchemys rememdium is notable for being the only documented species of trionychid in the mid Paleocene of the Williston Basin. The presence of multiple individuals in a carbonaceous claystone indicates this taxon lived in swamps and lakes and its expanded triturating surface suggests it had a durophagous diet. Supplementary Information: The online version contains supplementary material available at 10.1186/s13358-024-00315-8.

Synthesis of Borylated (Aminomethyl)cyclopropanes Using C1-Bisnucleophiles.

Lithiated 1,1-diborylalkanes have been used as nucleophilic coupling partners with a range of oxygen-based electrophiles, including esters, carbonyls, and epoxides. However, their reactivity with nitrogen-based electrophiles, such as aziridines, has remained relatively understudied. Herein, we show that lithiated 1,1-diborylalkanes react with α-halo and α-tosyl aziridines to yield borylated (aminomethyl)cyclopropanes-a privileged scaffold within medicinal chemistry. The reaction displays high levels of diastereoselectivity, enabling careful control of up to three stereocenters within a single transformation. DFT studies provide insight into the reaction mechanism, which diverges from that observed with analogous epihalohydrin starting materials. Derivatization studies were also performed on the products to demonstrate the utility of the boron and amine handles.

Factors Associated With Margin Positivity After Lung Resection Surgery.

INTRODUCTION: The purpose of this study is to utilize a representative national sample to investigate the factors associated with margin positivity after attempted surgical resection. Given the changes in surgical approaches to lung cancer for the last 10 years, margin positivity and outcomes between robotic, video assisted thoracoscopic surgery (VATS) and open surgical resections may vary. METHODS: This retrospective cohort study utilized the National Cancer Database. Patients with non-small-cell lung cancer, 18 or older and who had a surgical lung resection between 2010 and 2019 were included. Demographic data, along with patient-level clinical variables were extracted. Patient-level outcome variables including 30-day, 90-day mortality and readmission rates were analyzed. Univariable and multivariable logistic regression was utilized to assess factors associated with margin positivity. RESULTS: A total of 226,884 patients were identified. Of the total cohort, 9229 had positive margins (4.2%). Patients with positive margins had statistically significant increased 30-day, 90-day mortality, as well as increased readmission rate. Older age, male sex, patients undergoing an open resection, patients who underwent a wedge resection, higher clinical stage, larger tumor size, squamous and adenosquamous histologies, and higher Charlson-Deyo Comorbidity Index were all associated with having a positive margin after resection. CONCLUSION: In conclusion, there was no difference in margin positivity when comparing robotic and VATS resection, however, open resection had increased rates of margin positivity. Increasing tumor size, clinical stage, squamous and adenosquamous histologies, male sex, and patients undergoing a wedge resection were all associated with increased rates of margin positivity.

Relationship Between Hip Capsular Thickness and Instability After Previous Hip Arthroscopic Surgery: A Matched-Cohort Analysis.

Background: Thinner anterior hip capsules are associated with hip laxity, but there is little known about the impact of capsular thickness on the development of instability after primary hip arthroscopic surgery. Purpose: To investigate the relationship between hip capsular thickness as measured on preoperative magnetic resonance imaging (MRI) and the development of hip instability after hip arthroscopic surgery for femoroacetabular impingement. Study Design: Case-control study; Level of evidence, 3. Methods: We reviewed revision hip arthroscopic procedures performed between January 1, 2019, and May 1, 2021, at a single institution. Inclusion criteria were preoperative MRI/magnetic resonance arthrography, completion of the study traction protocol, and asymmetric distraction between the hips of ≥3 mm on examination under anesthesia. A comparison group of patients treated for femoroacetabular impingement with primary hip arthroscopic surgery who did not develop capsular instability were matched 1:1 to the patients with instability. Superolateral hip capsular thickness was measured on MRI before index surgery. Analysis was conducted using independent-samples t tests and multivariable linear regression. Results: A total of 44 patients were included, with 22 patients each in the instability and no-instability groups. The mean capsular thickness was lower in the patients with hip instability than in those without (1.9 ± 0.6 vs 3.4 ± 1.1 mm, respectively; P < .001). Decreased capsular thickness was significantly associated with hips with instability versus no-instability (ß = -1.468 [95% CI, -2.049 to -0.887]; P < .001). Conclusion: Thinner preoperative hip capsules in the region of the iliofemoral ligament were seen in patients who subsequently underwent revision arthroscopic surgery for hip instability compared to patients who underwent primary hip arthroscopic surgery without subsequent revision. Patients at a higher risk for the development of postoperative hip instability had a superolateral hip capsular thickness of <2 mm.

Compliant Intramedullary Stems for Joint Reconstruction.

The longevity of current joint replacements is limited by aseptic loosening, which is the primary cause of non-infectious failure for hip, knee, and ankle arthroplasty. Aseptic loosening is typically caused either by osteolysis from particulate wear, or by high shear stresses at the bone-implant interface from over-constraint. Our objective was to demonstrate feasibility of a compliant intramedullary stem that eliminates over-constraint without generating particulate wear. The compliant stem is built around a compliant mechanism that permits rotation about a single axis. We first established several models to understand the relationship between mechanism geometry and implant performance under a given angular displacement and compressive load. We then used a neural network to identify a design space of geometries that would support an expected 100-year fatigue life inside the body. We additively manufactured one representative mechanism for each of three anatomic locations, and evaluated these prototypes on a KR-210 robot. The neural network predicts maximum stress and torsional stiffness with 2.69% and 4.08% error respectively, relative to finite element analysis data. We identified feasible design spaces for all three of the anatomic locations. Simulated peak stresses for the three stem prototypes were below the fatigue limit. Benchtop performance of all three prototypes was within design specifications. Our results demonstrate the feasibility of designing patient- and joint-specific compliant stems that address the root causes of aseptic loosening. Guided by these results, we expect the use of compliant intramedullary stems in joint reconstruction technology to increase implant lifetime.

Cellular transfection using rapid decrease in hydrostatic pressure.

Of all methods exercised in modern molecular biology, modification of cellular properties through the introduction or removal of nucleic acids is one of the most fundamental. As such, several methods have arisen to promote this process; these include the condensation of nucleic acids with calcium, polyethylenimine or modified lipids, electroporation, viral production, biolistics, and microinjection. An ideal transfection method would be (1) low cost, (2) exhibit high levels of biological safety, (3) offer improved efficacy over existing methods, (4) lack requirements for ongoing consumables, (5) work efficiently at any scale, (6) work efficiently on cells that are difficult to transfect by other methods, and (7) be capable of utilizing the widest array of existing genetic resources to facilitate its utility in research, biotechnical and clinical settings. To address such issues, we describe here Pressure-jump-poration (PJP), a method using rapid depressurization to transfect even difficult to modify primary cell types such as embryonic stem cells. The results demonstrate that PJP can be used to introduce an array of genetic modifiers in a safe, sterile manner. Finally, PJP-induced transfection in primary versus transformed cells reveals a surprising dichotomy between these classes which may provide further insight into the process of cellular transformation.

Mutations of GEMIN5 are associated with coenzyme Q10 deficiency: long-term follow-up after treatment.

GEMIN5 exerts key biological functions regulating pre-mRNAs intron removal to generate mature mRNAs. A series of patients were reported harboring mutations in GEMIN5. No treatments are currently available for this disease. We treated two of these patients with oral Coenzyme Q10 (CoQ10), which resulted in neurological improvements, although MRI abnormalities remained. Whole Exome Sequencing demonstrated compound heterozygosity at the GEMIN5 gene in both cases: Case one: p.Lys742* and p.Arg1016Cys; Case two: p.Arg1016Cys and p.Ser411Hisfs*6. Functional studies in fibroblasts revealed a decrease in CoQ10 biosynthesis compared to controls. Supplementation with exogenous CoQ10 restored it to control intracellular CoQ10 levels. Mitochondrial function was compromised, as indicated by the decrease in oxygen consumption, restored by CoQ10 supplementation. Transcriptomic analysis of GEMIN5 patients compared with controls showed general repression of genes involved in CoQ10 biosynthesis. In the rigor mortis defective flies, CoQ10 levels were decreased, and CoQ10 supplementation led to an improvement in the adult climbing assay performance, a reduction in the number of motionless flies, and partial restoration of survival. Overall, we report the association between GEMIN5 dysfunction and CoQ10 deficiency for the first time. This association opens the possibility of oral CoQ10 therapy, which is safe and has no observed side effects after long-term therapy.

Lipid profile of circulating placental extracellular vesicles during pregnancy identifies foetal growth restriction risk.

Small-for-gestational age (SGA) neonates exhibit increased perinatal morbidity and mortality, and a greater risk of developing chronic diseases in adulthood. Currently, no effective maternal blood-based screening methods for determining SGA risk are available. We used a high-resolution MS/MSALL shotgun lipidomic approach to explore the lipid profiles of small extracellular vesicles (sEV) released from the placenta into the circulation of pregnant individuals. Samples were acquired from 195 normal and 41 SGA pregnancies. Lipid profiles were determined serially across pregnancy. We identified specific lipid signatures of placental sEVs that define the trajectory of a normal pregnancy and their changes occurring in relation to maternal characteristics (parity and ethnicity) and birthweight centile. We constructed a multivariate model demonstrating that specific lipid features of circulating placental sEVs, particularly during early gestation, are highly predictive of SGA infants. Lipidomic-based biomarker development promises to improve the early detection of pregnancies at risk of developing SGA, an unmet clinical need in obstetrics.

Association between surgical quality and long-term survival in lung cancer.

OBJECTIVES: There are significant variations in both perioperative and long-term outcomes after lung cancer resection. While perioperative outcomes are often used as comparative measures of quality, they are unreliable, and their association with long-term outcomes remain unclear. In this context, we evaluated whether historical perioperative mortality after lung cancer resection is associated with 5-year survival. PATIENTS AND METHODS: The National Cancer Database (NCDB) was queried to identify patients diagnosed with non-small cell lung cancer (NSCLC) in 2010-2016 who underwent surgical resection (n = 234200). Hospital-level reliability-adjusted 90-day mortality rate quartiles for 2010-2013 was used as the independent variable to analyze 5-year survival for patients diagnosed in 2014-2016 (n = 85396). RESULTS: There were 85,396 patients in the 2014-2016 cohort across 1,086 hospitals. Overall observed 90-day mortality rate was 3.2% (SD 17.6%) with 2.6% (SD 16.0%) for the historically best performing quartile vs. 3.9% (SD 19.4%) for the worst performing quartile (p < 0.0001). Patients who underwent resection at hospitals with the best historical mortality rate had significantly better 5-year survival across all stages compared to those treated at hospitals in the worst performing quartile in multivariate Cox regression analysis (all stages - HR 1.21 [95% CI 1.15-1.26]; stage I - HR 1.19 [95% CI 1.12-1.25]; stage II - HR 1.20 [95% CI 1.09-1.32]; stage III - HR 1.36 [95% CI 1.20-1.54]) and Kaplan-Meier survival estimates (all stages - p < 0.0001, stage I - p < 0.0001; stage II - p = 0.0004; stage III - p < 0.0001). CONCLUSION: With expanded lung cancer screening criteria and likely increase in early-stage detection, profiling performance is paramount to ensuring mortality benefits. We found that episodes surrounding surgical resection may be used to profile long-term outcomes that likely reflect quality across a broader context of care. Evaluating lung cancer care quality using perioperative outcomes may be useful in profiling provider performance and guiding value-based payment policies.