Performance evaluation of three versions of a convolutional neural network for object detection and segmentation using a multiclass and reduced panoramic radiograph dataset

OBJECTIVES

To evaluate the diagnostic performance of three versions of a deep-learning convolutional neural network in terms of object detection and segmentation using a multiclass panoramic radiograph dataset.

METHODS

A total of 600 orthopantomographies were randomly selected for this study and manually annotated by a single operator using an image annotation tool (COCO Annotator v.11.0.1) to establish ground truth. The annotation classes included teeth, maxilla, mandible, inferior alveolar nerve, dento- and implant-supported crowns/pontics, endodontic treatment, resin-based restorations, metallic restorations, and implants. The dataset was then divided into training, validation, and testing subsets, which were used to train versions 5, 7, and 8 of You Only Look Once (YOLO) Neural Network. Results were stored, and a posterior performance analysis was carried out by calculating the precision (P), recall (R), F1 Score, Intersection over Union (IoU), and mean average precision (mAP) at 0.5 and 0.5-0.95 thresholds. The confusion matrix and recall precision graphs were also sketched.

RESULTS

YOLOv5s showed an improvement in object detection results with an average R = 0.634, P = 0.781, mAP0.5 = 0.631, and mAP0.5-0.95 = 0.392. YOLOv7m achieved the best object detection results with average R = 0.793, P = 0.779, mAP0.5 = 0.740, and mAP0.5-0.95 = 0,481. For object segmentation, YOLOv8m obtained the best average results (R = 0.589, P = 0.755, mAP0.5 = 0.591, and mAP0.5-0.95 = 0.272).

CONCLUSIONS

YOLOv7m was better suited for object detection, while YOLOv8m demonstrated superior performance in object segmentation. The most frequent error in object detection was related to background classification. Conversely, in object segmentation, there is a tendency to misclassify True Positives across different dental treatment categories.

CLINICAL SIGNIFICANCE

General diagnostic and treatment decisions based on panoramic radiographs can be enhanced using new artificial intelligence-based tools. Nevertheless, the reliability of these neural networks should be subjected to training and validation to ensure their generalizability.

Prognostic Significance of Positron Emission Tomography Delta Radiomics Following Bridging Therapy in Patients with Large B-Cell Lymphoma Undergoing CAR T-Cell Therapy

PURPOSE/OBJECTIVE(S)

CAR T-cell therapy is routinely used as a treatment option for relapsed/refractory large B-cell lymphoma (LBCL). Bridging therapy radiation therapy (bRT) is increasingly being utilized prior to chimeric antigen receptor (CAR) T-cell therapy for large B-cell lymphoma (LBCL). It is unknown how the extent of debulking as a result of bRT impacts outcomes following CAR T-cell infusion. We hypothesized that the extent of debulking is prognostic of overall response to therapy.

MATERIALS/METHODS

We reviewed patients with LBCL treated with bRT followed by commercially available CAR T-cell therapy between 2017 and 2022. Patients required a F-fluorodeoxyglucose (FDG) positron emission tomography (PET) scan prior to bRT and between completion of bRT and CAR T-cell infusion. On each scan, metabolic tumor volume (MTV), maximum standardized uptake value (SUVmax), SUVmean, and total lesion glycolysis (TLG) were determined. Delta-radiomics based on changes of these values between scans in patients overall and irradiated sites were then calculated. Optimal cut points were determined using maximally selected log-rank. The primary endpoints were progression-free survival (PFS) and local control (LC), measured from CAR T-cell infusion by Kaplan-Meier and Fine-Gray competing risk survival analyses, respectively.

RESULTS

Twenty-three patients with LBCL with 33 irradiated sites were reviewed. All metabolically active disease was treated in 10 patients. Median equivalent dose in 2 Gy fractions (EQD2) was 26 Gy (14-44). Median interval from bRT to PET was 9 days (2-30). Following bRT, 2 patients achieved complete responses, 16 had partial responses, and 5 had progressive disease. Five irradiated sites progressed through bRT. No local failures were observed when EQD2>32.5 Gy was given. LC was improved with EQD2>20 Gy (24 mo LC: 94.5% vs 68.6%; p = 0.075). Following BRT, median overall decreases in MTV, SUVmax, SUVmean, and TLG were 22.2 cc (63.1%), 8.9 (36.8%), 3.4 (31.1%), and 297.9 cc (75.8%), respectively. Median decreases in MTV, SUVmax, SUVmean, and TLG in irradiated sites were 15.6 cc (91.1%), 17.0 (74.6%), 6.8 (55.3%), and 157.0 cc (94.6%), respectively. PFS was significantly improved in patients with reductions of MTV of at least 36 cc (24 mo PFS: 69.2% vs 0%; p = 0.047) or SUVmax of at least 15 (24-mo PFS: 80.0% vs 28.1%; p < 0.001). LC was significantly improved in lesions with reductions of SUVmax of at least 14 (24-mo LC: 100% vs 67.3%; p < 0.001) or SUVmean of at least 7 (24-mo LC: 100% vs 74.4%; p < 0.001).

CONCLUSION

bRT led to significant reductions in MTV, SUVmax, SUVmean, and TLG. The extent of these decreases correlated with improved PFS and LC. There appears to be a dose-response relationship. Larger cohorts should validate the value of interim PET following bRT, and associated changes in disease burden as a means of prognosticating patients. Future work might evaluate whether escalation of BT in patients with suboptimal response, using either systemic therapy or higher radiation doses, has an impact on outcomes.

Long Term Evaluation of Cardiac Events and Outcomes Following Breast Cancer Irradiation

PURPOSE/OBJECTIVE(S)

Although whole heart dose has been associated with cardiac toxicity in patients receiving radiation therapy for breast cancer, data detailing the clinical significance of cardiac substructures, particularly the left anterior descending artery (LAD), are limited. We investigated whether dose to the LAD correlates with adverse cardiac events and death.

MATERIALS/METHODS

We identified 190 female patients treated from 2002 to 2019 who received breast or chest wall irradiation, with or without regional nodal irradiation. Ninety-three patients were treated on their right side, 95 on their left, and two were bilateral. Medical records were queried in healthcare software to identify cardiac events after radiation therapy. Mean and maximum LAD and heart doses, as well as V15LAD, were calculated. Univariate and multivariate Cox regression analyses were performed to determine their association with cardiac toxicity as well as death. Cumulative incidence curves for death and cardiac toxicity were also calculated for the patient population.

RESULTS

Median follow-up time was 68 months. Thirty patients experienced a cardiac event (15.7%), with three of these being grade 3 or higher. On univariate analyses, left side (hazard ratio 8, P<0.001), increased Mean LAD Dose per cGy (1.001, P = 0.01), Mean Heart Dose (1.16, P = 0.01), and anatomic stage (3.5, P = 0.003) were statistically significant predictors of death but not of adverse cardiac events. Statistically significant predictors of adverse cardiac events were the receipt of chemotherapy (2.68, p = 0.046) which remained significant even after adjusting for radiation parameters. There was no association with hormonal therapy use. Cumulative incidence curves predicted a 14.11% probability of a cardiac event 5 years after treatment and a 25.7% probability at 10 years after treatment. They also predicted a 9.43% probability of death at both 5- and 10-years post-treatment.

CONCLUSION

On this long-term analysis, doses to the heart seemed to negatively impact survival, but did not have a clear association between cardiac events. In contrast, utilizing cytotoxic systemic therapy seemed have an association, even when adjusted for on multivariable models for cardiac events.

P-481 Characterization of the gene expression profile of breast cancer tumours in patients undergoing ovarian stimulation for fertility preservation purposes

Study question

Could controlled ovarian stimulation (COS) protocols with letrozole supplementation induce changes in the molecular footprints of estrogen receptor-positive (ER+) breast cancer (BC) women?

Summary answer

Ovarian stimulation with letrozole and gonadotropins does not change the gene expression profile of estrogen receptor-positive (ER+) breast malignant tumours as compared to non-stimulated patients.

What is known already

Fertility preservation (FP) strategies in ER+ BC patients involve modifications of the classical COS protocols to minimise the impact of estrogen levels during ovarian stimulation. The most common approaches are using the aromatase inhibitor letrozole to block the conversion of testosterone into estradiol in the granulosa cells or the use of tamoxifen to block the ER in the breast tissue. Although retrospective studies suggest that these strategies will have no impact on patient’s survival and disease progression, little is known regarding the effect of the ovarian stimulation on the genomic fingerprints of the exposed cancerous tissue.

Study design, size, duration

Retrospective, non-randomized, comparative study. Gene expression profiles were compared in biopsies at diagnosis and during excision surgery in two groups of ER+ BC patients: Patients undergoing COS for FP before surgery (COS group, n = 10) and patients not undergoing any type of COS (Control group, n = 11). The former received letrozole (5mg/day) supplements during COS. The latter included 7 patients not doing FP and 4 undergoing ovarian cortex cryopreservation. Patients were recruited between 2009 and 2021.

Participants/materials, setting, methods

Single 5-µm sections of formalin-fixed, paraffin-embedded (FFPE) needle core biopsy (NCB) and breast surgery (BS) tumour samples were obtained prior to starting gonadotoxic therapies. Differential gene expression and gene set analysis (GSA) was performed in tumour samples before (NCB-sample) and after COS (BS-sample). Simultaneous, quantitative detection of 2549 genes associated with tumour biology was performed with the HTG EdgeSeq Oncology Biomarker Panel. Tumour cell proliferation was also assessed by Ki67 staining.

Main results and the role of chance

Patients were younger in the COS group (COS: 30.2±3.4 vs Control: 34.5±2.3; p = 0.004). None of the patients experienced any relapse during the observation period. The length of COS was 11.5±3.5 days and 10.6±6.8 MII oocytes were vitrified. The exploratory analysis using principal component analysis revealed no relationships between the two BC biopsy samples and gene expression levels in the experimental groups. The differential expression analysis just revealed 6 genes significantly over-expressed after ovarian stimulation (DUSP1, FOS, EGFR1, NR4A1, JUN and CYR61). From these, DUSP1, FOS, and NR4A1 were also significantly upregulated in the unstimulated group. The GSA showed the cytochrome P450 pathway was significantly enriched after COS. No pathways related to cell proliferation were differentially expressed between groups. However, in unstimulated patients, 6 KEGG pathways were upregulated, with the cytokine-cytokine receptor interaction and the Jak-STAT signalling pathway being the most enriched. Ki67 immunostaining showed no differences in cell proliferation after COS (22.8±7.2 vs 24.0±6.9, p = 0.723). The rate of cell proliferation also remained constant in unstimulated patients (22.9±8.4 vs 25.1±8.1, p = 0.560).

Limitations, reasons for caution

The main limitations of the present study are the retrospective design and the associated risk of bias, although the population is very homogeneous when it comes to clinical characteristics; and the fact that molecular footprints are only interim markers of survival/response to the treatment.

Wider implications of the findings

The present study provides molecular evidence supporting the safety of COS using letrozole for oocyte vitrification in young BC patients undergoing ovarian stimulation. This information is crucial to support patient guidance during discussions about fertility preservation.

Trial registration number

Not applicable

[IGG4-related disease. Report of 52 patients]

BACKGROUND

IgG4-related disease (IgG4 RD) is an immune-mediated fibro-inflammatory disorder, with tissue infiltration of IgG4+ plasma cells. It causes pseudotumors, tumors, and a wide spectrum of clinical manifestations.

AIM

To report the clinical, laboratory, histopathological and treatment characteristics of a group of Chilean patients with IgG4 RD.

MATERIAL AND METHODS

Review of medical records of 52 patients aged 18 to 76 years with IgG4 RD seen at six medical centers.

RESULTS

Elevated IgG4 serum levels (> 135 mg/dl) were found in 18 of 44 (41%) patients. There was histological confirmation of the disease in 46 patients. The most common sites of involvement were lungs, eyes and kidneys. Eighteen (35%) patients had only one organ involved, 34 (65%) patients had two organs and 13 (25%) patients had three or more organs. The involvement of two organs was significantly more common in men (p < 0.05). In patients with only one organ involvement, the most frequent location was orbital and meningeal. All patients with kidney or lung disease had multiorgan involvement. All patients received corticosteroid therapy, 67% synthetic immunosuppressants, and 16% rituximab.

CONCLUSIONS

ER-IgG4 can affect any tissue. Multiorgan involvement was more common in this series, with preference for lungs, eyes and kidneys. An excellent response to steroids is characteristic of the disease, but with a high relapse rate that requires additional immunosuppression.

Condylar morphometry in adults with sagittal intermaxillary relationship class I, II and III using Cone Beam Computed Tomography in a Colombian population

OBJECTIVE

This study established the morphometry of the mandibular condyle in individuals with complete craniofacial growth and sagittal intermaxillary relationships class I, II and III using cone beam computed tomography (CBCT).

MATERIALS AND METHODS

Cone beam computed tomography was obtained for orthodontics diagnostic purposes. The sample was divided taking into account the ANB angle in sagittal classes I, II and III (age ranged from 18 to 40 years old). Linear measurements and shapes of 144 mandibular condyles were analyzed.

RESULTS

Statistically significant differences were found in measurements of the mediolateral diameter when compared with gender (P 0.000) being larger for males. Statistically significant differences between the mediolateral diameter and the coronal shape for the right as well as the left sides with P values of 0.000 and 0.47 respectively were found.

CONCLUSION

In this sample, it was not possible to conclusively determine the relationship between the skeletal class and the mediolateral diameter. However, more studies are required.

Are the unreamed nails indicated in diaphyseal fractures of the lower extremity? A biomechanical study

INTRODUCTION

Intramedullary nailing is generally accepted as the first choice for the treatment of diaphyseal fractures of femur and tibia, with a gradual incease in the use of unreamed nails. Different studies during last years show controversial outcomes. Some authors strongly favor unreamed nailing, but most of the authors conclude that reamed nailing have proved to be more successful.

MATERIAL AND METHODS

This study simulates unreamed intramedullary nailing of four femoral and three tibial fracture types by means of Finite Element (FE) models, at early postoperative stages with a fraction of physiological loads, in order to determine whether sufficient stability is achieved, and if the extent of movements and strains at the fracture site may preclude proper consolidation.

RESULTS

The behavior observed in the different fracture models is very diverse. In the new biomechanical situation, loads are only transmitted through the intramedullary nail. Mean relative displacement values of fractures in the femoral bone range from 0.30 mm to 0.82 mm, depending on the fracture type. Mean relative displacement values of the tibial fractures lie between 0.18 and 0.62 mm, depending on the type of fracture. Concerning mean strains, for femoral fractures the maximum strains ranged between 12.7% and 42.3%. For tibial fractures the maximum strains ranged between 10.9% and 40.8%.

CONCLUSIONS

The results showed that unreamed nailing provides a very limited mechanical stability, taking into account that analyzed fracture patterns correspond to simple fracture without comminution. Therefore, unreamed nailing is not a correct indication in femoral fractures and should be an exceptional indication in open tibial fractures produced by high-energy mechanism.

Ketamine specifically reduces cognitive symptoms in depressed patients: An investigation of associated neural activation patterns

Major depressive disorder (MDD) is characterized by heterogeneous cognitive, affective and somatic symptoms. Hence, the investigation of differential treatment effects on these symptoms as well as the identification of symptom specific biomarkers might crucially contribute to the development of individualized treatment strategies. We here aimed to examine symptom specific responses to treatment with ketamine, which repeatedly demonstrated rapid antidepressant effects in severe MDD. Additionally, we investigated working memory (WM) related brain activity associated with changes in distinct symptoms in order to identify specific response predictors. In a sample of 47 MDD patients receiving a single sub-anesthetic dose of ketamine, we applied a three-factor solution of the Beck Depression Inventory (BDI) to detect symptom specific changes 24 h post-infusion. A subsample of 16 patients underwent additional fMRI scanning during an emotional working memory task prior to ketamine treatment. Since functional aberrations in the default mode network (DMN) as well as in the dorsolateral prefrontal cortex (DLPFC) have been associated with impaired cognitive and emotional processing in MDD, we investigated neural activity in these regions. Our results showed that ketamine differentially affects MDD symptoms, with the largest symptom reduction in the cognitive domain. WM related neuroimaging results indicated that a more pronounced effect of ketamine on cognitive symptoms is predicted by lower DMN deactivation and higher DLPFC activation. Findings thereby not only indicate that ketamine's antidepressant efficacy is driven by a pro-cognitive mechanism, but also suggest that this might be mediated by increased potential for adaptive adjustment in the circumscribed brain regions.

New benzimidazolequinones as trypanosomicidal agents

Herein, the design and synthesis of new 2-phenyl(pyridinyl)benzimidazolequinones and their 5-phenoxy derivatives as potential anti-Trypanosoma cruzi agents are described. The compounds were evaluated in vitro against the epimastigotes and trypomastigote forms of Trypanosoma cruzi. The replacing of a benzene moiety in the naphthoquinone system by an imidazole enhanced the trypanosomicidal activity against Trypanosoma cruzi. Three of the tested compounds (11a-c) showed potent trypanosomicidal activity and compound 11a, with IC₅₀ of 0.65 μM on the trypomastigote form of T. cruzi, proved to be 15 times more active than nifurtimox. Additionally, molecular docking studies indicate that the quinone derivatives 11a-c could have a multitarget profile interacting preferentially with trypanothione reductase and Old Yellow Enzyme.

Cervical Cancer Screening with Human Papillomavirus Self-Sampling Among Transgender Men in El Salvador

Purpose: Sexual and gender minority persons in low-income countries have very limited access to routine health services. This study evaluated the feasibility of using a self-sampled human papillomavirus (HPV) test to increase access to screening for cervical cancer among transgender men in El Salvador. Methods: We partnered with a local advocacy organization for recruitment. A total of 24 transgender men (men assigned female at birth) ages 19-55 were enrolled and provided consent. Questionnaires assessed sociodemographics, health and sexual histories, and knowledge about HPV and cervical cancer. Screening was performed with a self-sampled HPV test. Participants with a positive test were offered colposcopy and cryotherapy treatment, if appropriate. Those with a negative test were advised to return in 5 years for rescreening. Results: Out of 24 consenting participants, 23 (95.83%) agreed to conduct HPV self-sampling, and 22/23 (95.65%) expressed willingness to self-sample in the future. Among self-sampled individuals, 3/23 (13%) tested positive and accepted colposcopy and biopsy. Analyses of biopsied tissue revealed one case of cervical intraepithelial neoplasia grade 1. Conclusion: HPV self-sampling and subsequent procedures were accepted by the majority of participants. This screening method may be a viable alternative to cytology among transgender men in El Salvador.

First evaluation of neustonic microplastics in the Macaronesian region, NE Atlantic

Marine microplastic pollution is an issue of great concern nowadays since high concentrations have been detected in the ocean, mainly in the subtropical gyres that accumulate this type of debris. The long-term effects of this pollution on ecosystems and marine biota are still unknown. The aim of this study is to quantify and characterise microplastics and neustonic zooplankton in sub-surface waters of the Macaronesian region, an area that has been little studied to date. Our results show a great variability in the concentration of microplastics with values between 15,283 items/km² in Los Gigantes (Tenerife, Canary Islands) and 1,007,872 items/km² in Las Canteras (Gran Canaria, Canary Islands). The main types of debris found were plastic fragments and fibres. The abundances of neustonic zooplankton were also very variable between the different sampling areas, being the main components copepods and eggs. Regarding the microplastics-zooplankton ratio, values were obtained between 0.002 and 0.22. In Las Canteras, the highest accumulation zone, was found twice as much microplastics as zooplankton for the 1-5 mm fraction in dry weight. These values highlight the potential hazard of microplastics - and its associated chemical contaminants - for marine biota, especially for large filter feeders.

Biomechanical analysis of the stability of anterograde reamed intramedullary nails in femoral spiral fractures

Femoral shaft fractures present high morbidity and important complications and consequences, being spiral fractures the most complicated from a biomechanical point of view, being unstable and without possibility of getting a good contact between nail and femoral endosteum. Femoral diaphyseal fractures are treated, usually, by means of intramedullary nailing. So, it is necessary to know the osteosynthesis stability and which locking screws combination is optimal. This work studies the use of reamed locked intramedullary nails in spiral femoral fractures located along zones 2 and 4 of wiss, depending on the spire length, corresponding to 32-A spiral type in AO/OTA classification, which represent a percentage of 23% within the total of diaphyseal fractures. A three-dimensional finite element model of the femur was developed, modeling a spiral fracture with different spiral lengths and gaps. A femoral nail was used, considering two transversal screws both at the proximal and the distal parts. The study was focused on the immediately post-operative stage, verifying the appropriate stability of the osteosynthesis. Reamed intramedullary blocked nails provide appropriate stability of femoral spiral fractures, considering global mobility of femoral head with respect to femoral condyles, relative displacements between fragments at fracture site, stresses at nail and locking screws, and stresses at cortical bone. The obtained results show that the use of blocked reamed nails in spiral femoral fractures can be considered as an appropriate surgical technique, providing sufficient stability in order to obtain an adequate fracture healing.

Risk factors for major adverse cardiovascular events after osteoporotic hip fracture repair surgery

Osteoporotic hip fracture (OHF) is an increasingly frequent age-related pathology, which results in high rates of functional loss and mortality within the first year after surgery. This study assessed whether preoperative levels of brain natriuretic peptide (NT-proBNP) and troponin I were related to early occurrence (30d) of major adverse cardio-vascular events (MACE) after OHF repair surgery. During a 6-month period, perioperative clinical and analytical data from consecutive patients, without known history of cardiovascular disease and undergoing surgery for OHF repair at a single centre, were prospectively collected. MACE was defined as acute myocardial ischaemia or infarction, acute heart failure or cardiovascular death. amongst the 140 patients included, 23 (16.4%) developed postoperative MACE (MACE group) and 117 did not (Control group). Compared to those from control group, patients from MACE group were older, had poorer physical status (ASA III-IV), received preoperative red blood cell transfusion (RBCT) more frequently, presented with lower haemoglobin concentrations and higher NT-proBNP, creatinine and troponin I concentrations. Overall, RBCT requirements and 30d mortality rate were also higher in MACE group. However, in multivariate analysis, only preoperative RBCT, creatinine >1 mg/dL and NT-proBNP >450 pg/mL remained as independent preoperative risks factors for postoperative MACE, while 95% confidence intervals of odds ratios were wide. Though our findings require confirmation in a larger multicentre cohort, identifying risk factors for early postoperative MACE after OHF repair surgery, might facilitate assessing patients' risk prior to and following surgery, and targeting them the appropriate preventive and/or therapeutic interventions.

Microplastic ingestion by Atlantic chub mackerel (Scomber colias) in the Canary Islands coast

In recent years, due to the increasing concerns about their negative impact on wildlife and possible toxicity to living organisms (including humans), microplastics have become the subject of intense investigations. In the ocean, microplastics can be easily ingested by numerous marine organisms because of their small size (<5 mm). The Northwest African upwelling system is an important fishery area, and the present study is the first one in the region to reveal the presence of microplastic particles in the digestive tract of Atlantic chub mackerel (Scomber colias). From the 120 examined fish gastrointestinal tracts, 78.3% contained some type of microplastics, 74.2% contained fibres, 17.5% plastic fragments, and 16.7% paint. More studies are needed on fish, but S. colias is a candidate for being a good indicator of microplastic contamination in the region.

The impact of hip fracture on health-related quality of life and activities of daily living: the SPARE-HIP prospective cohort study

PURPOSE

The medical morbidity and mortality associated with neck of femur fractures is well-documented, whereas there is limited data for patient-reported outcomes. The aim of this study was to characterize the impact of neck of femur fractures on activities of daily living and patient-reported health-related quality of life.

METHODS

Design and participants: Multicentric prospective cohort study. Consecutive sample patients with fragility hip fracture over 50 years old admitted in 48 hospitals in Spain.

OUTCOMES

daily living activity function (Barthel Index) and health-related quality of life (EQ-5D) pre-fracture, admission to hospital and at 1- and 4-month follow-up post-fracture.

STATISTICS

Barthel and EQ-5D over time are described as mean (SD) and median (interquartile range).

RESULTS

A total of 997 patients were recruited at baseline with 4-month outcomes available for, and 856 patients (89.5%). Barthel Index fell from 78.77 (23.75) at baseline to 43.62 (19.86) on admission to hospital with the fracture. Scores partially recovered to 54.89 (25.40) and 64.09 (21.35) at 1- and 4-month post-fracture, respectively. EQ-5D fell from a median of 0.75 (0.47-0.91) to - 0.01 (- 0.03 to 0.51) on admission. Partial recovery was observed again to (0.51 (- 0.06 to 0.67)) and (0.60 (0.10 to 0.80)) at 1- and 4-month post-fracture, respectively.

CONCLUSIONS

Hip fracture results in a large decline in the ability to perform activities of daily living and patient-reported health-related quality of life with only partial recovery amongst survivors 4-month post-fracture.

A biomaterial with a channel-like pore architecture induces endochondral healing of bone defects

Biomaterials developed to treat bone defects have classically focused on bone healing via direct, intramembranous ossification. In contrast, most bones in our body develop from a cartilage template via a second pathway called endochondral ossification. The unsolved clinical challenge to regenerate large bone defects has brought endochondral ossification into discussion as an alternative approach for bone healing. However, a biomaterial strategy for the regeneration of large bone defects via endochondral ossification is missing. Here we report on a biomaterial with a channel-like pore architecture to control cell recruitment and tissue patterning in the early phase of healing. In consequence of extracellular matrix alignment, CD146+ progenitor cell accumulation and restrained vascularization, a highly organized endochondral ossification process is induced in rats. Our findings demonstrate that a pure biomaterial approach has the potential to recapitulate a developmental bone growth process for bone healing. This might motivate future strategies for biomaterial-based tissue regeneration.

The impact of advanced practice providers on the surgical resident experience: Agree to disagree?

BACKGROUND

We examined and compared APP versus surgical resident perceptions of the role of APPs in surgical subspecialty teams.

METHODS

Residents/first year surgical critical care fellows and inpatient service-specific APPs responded to a survey that examined perceptions about the APP-resident/fellow relationship. Statistical analysis compared responses using a Pearson chi-square test.

RESULTS

Thirty-two resident/fellows (48%) and 10 APPs (42%) responded. There was consensus that having an APP on service decreases workload, contributes to continuity of care and enhances resident-patient coordination education and agreement that there was clear communication and adequate collaboration. Both groups differed with respect to APPs contribution to resident/fellow clinical education, role definition and chain of command. The majority of trainees felt that APPs function at a PGY2 level (51.7%) compared to APPs, who felt that they functioned at a PGY4/5 (22%) or Fellow (44%) level.

CONCLUSION

APPs and resident/fellows agree that APPs impact resident workload, continuity of care and patient-coordination education.

Microplastic and tar pollution on three Canary Islands beaches: An annual study

Marine debris accumulation was analyzed from three exposed beaches of the Canary Islands (Lambra, Famara and Las Canteras). Large microplastics (1-5mm), mesoplastics (5-25mm) and tar pollution were assessed twice a month for a year. There was great spatial and temporal variability in the Canary Island coastal pollution. Seasonal patterns differed at each location, marine debris concentration depended mainly of local-scale wind and wave conditions. The most polluted beach was Lambra, a remote beach infrequently visited. The types of debris found were mainly preproduction resin pellets, plastic fragments and tar, evidencing that pollution was not of local origin, but it cames from the open sea. The levels of pollution were similar to those of highly industrialized and contaminated regions. This study corroborates that the Canary Islands are an area of accumulation of microplastics and tar rafted from the North Atlantic Ocean by the southward flowing Canary Current.

Cervical Cancer Screening in Transgender Men in El Salvador: A Pilot Study

Abstract 27

Purpose

Transgender persons are particularly vulnerable to a lack of adequate health care, particularly with regard to sexual and reproductive health. In El Salvador, where cervical cancer is a leading cause of cancer death, transgender men are at high risk of developing this disease. Whereas the Papanicolaou test is the most widely used screening method for cervical cancer, there are reports of high numbers of unsatisfactory results among transgender men compared with nontransgender persons. Human papillomavirus (HPV) testing may be a more viable screening option in this population. In this pilot study, we assessed the feasibility of cervical cancer screening among transgender men using a self-sampling HPV test as an alternative to the Papanicolaou test.

Methods

Participants were transgender men of the Organización Generación Hombres Trans El Salvador (Trans Men Generation Organization of El Salvador) between age 19 and 55 years. After obtaining informed consent, a questionnaire was administered to 24 participants to collect sociodemographic, lifestyle, and sexual behavior data, and to assess knowledge about cervical cancer prevention. Participants then performed a vaginal, self-sampling HPV test. Participants who received a positive HPV result were offered a colposcopy evaluation.

Results

Almost all participants—23 of 24—agreed to conduct vaginal self-sampling. Of these, three (13%) of 23 participants tested positive, with the remainder obtaining a negative result. Colposcopies and biopsies were accepted by all three participants who tested positive. One participant was diagnosed with CIN3, whereas two2 were diagnosed with CIN1.

Conclusion

There is limited information on cervical cancer prevention among transgender men, particularly in low and middle-income countries. Use of HPV self-sampling tests is a viable method that can significantly improve participation in and acceptance of screening in this vulnerable population. HPV testing may reduce the number of unsatisfactory results generated when using Papanicolaou tests as a screening method.

AUTHORS' DISCLOSURES OF POTENTIAL CONFLICTS OF INTEREST

No COIs from the authors.

Mechanosensation across borders: fibroblasts inside a macroporous scaffold sense and respond to the mechanical environment beyond the scaffold walls

In tissue defects, cells face distinct mechanical boundary conditions, but how this influences early stages of tissue regeneration remains largely unknown. Biomaterials are used to fill defects but also to provide specific mechanical or geometrical signals. However, they might at the same time shield mechanical information from surrounding tissues that is relevant for tissue functionalisation. This study investigated how fibroblasts in a soft macroporous biomaterial scaffold respond to distinct mechanical environments while they form microtissues. Different boundary stiffnesses counteracting scaffold contraction were provided via a newly developed in vitro setup. Online monitoring over 14 days revealed 3.0 times lower microtissue contraction but 1.6 times higher contraction force for high vs. low stiffness. This difference was significant already after 48 h, a very early stage of microtissue growth. The microtissue's mechanical and geometrical adaptation indicated a collective cellular behaviour and mechanical communication across scaffold pore walls. Surprisingly, the stiffness of the environment influenced cell behaviour even inside macroporous scaffolds where direct cell-cell contacts are hindered. Mechanical communication between cells via traction forces is essential for tissue adaptation to the environment and should not be blocked by rigid biomaterials. Copyright © 2017 John Wiley & Sons, Ltd.

EULAR/EFORT recommendations for management of patients older than 50 years with a fragility fracture and prevention of subsequent fractures

The European League Against Rheumatism (EULAR) and the European Federation of National Associations of Orthopaedics and Traumatology (EFORT) have recognised the importance of optimal acute care for the patients aged 50 years and over with a recent fragility fracture and the prevention of subsequent fractures in high-risk patients, which can be facilitated by close collaboration between orthopaedic surgeons and rheumatologists or other metabolic bone experts. Therefore, the aim was to establish for the first time collaborative recommendations for these patients. According to the EULAR standard operating procedures for the elaboration and implementation of evidence-based recommendations, 7 rheumatologists, a geriatrician and 10 orthopaedic surgeons met twice under the leadership of 2 convenors, a senior advisor, a clinical epidemiologist and 3 research fellows. After defining the content and procedures of the task force, 10 research questions were formulated, a comprehensive and systematic literature search was performed and the results were presented to the entire committee. 10 recommendations were formulated based on evidence from the literature and after discussion and consensus building in the group. The recommendations included appropriate medical and surgical perioperative care, which requires, especially in the elderly, a multidisciplinary approach including orthogeriatric care. A coordinator should setup a process for the systematic investigations for future fracture risk in all elderly patients with a recent fracture. High-risk patients should have appropriate non-pharmacological and pharmacological treatment to decrease the risk of subsequent fracture.

Note. Pollen Analysis and Antibacterial Activity of Spanish Honeys

Antibacterial activity of twenty-five samples of honey from different botanical origin was evaluated. Staphylococcus aureus ATCC 25923 was used as the resistant microorganism. Pollen analysis revealed different botanical origins: Labiatae, rosemary, eucalyptus, heather and multifloral. The pH and acidity values were in the normal range, except for four samples that showed acidity values over 40 meq/kg, but none exhibited a state of fermentation. We have not found correlation between antibacterial activity and free acidity in the samples. Labiatae and rosemary honeys have exhibited the largest inhibition against Staphylococcus aureus ATCC, conversely to heather honeys, which showed lowest inhibition ability against this microorganism. Our results may indicate the presence of antimicrobial agents in Labiatae and rosemary honeys that have inhibited the growth of Staphylococcus aureus ATCC. Likewise, the free acids of heather honeys have not shown inhibitory activity over this microorganism.

A predictive mechanical model for evaluating vertebral fracture probability in lumbar spine under different osteoporotic drug therapies

Osteoporotic vertebral fractures represent a major cause of disability, loss of quality of life and even mortality among the elderly population. Decisions on drug therapy are based on the assessment of risk factors for fracture from bone mineral density (BMD) measurements. A previously developed model, based on the Damage and Fracture Mechanics, was applied for the evaluation of the mechanical magnitudes involved in the fracture process from clinical BMD measurements. BMD evolution in untreated patients and in patients with seven different treatments was analyzed from clinical studies in order to compare the variation in the risk of fracture. The predictive model was applied in a finite element simulation of the whole lumbar spine, obtaining detailed maps of damage and fracture probability, identifying high-risk local zones at vertebral body. For every vertebra, strontium ranelate exhibits the highest decrease, whereas minimum decrease is achieved with oral ibandronate. All the treatments manifest similar trends for every vertebra. Conversely, for the natural BMD evolution, as bone stiffness decreases, the mechanical damage and fracture probability show a significant increase (as it occurs in the natural history of BMD). Vertebral walls and external areas of vertebral end plates are the zones at greatest risk, in coincidence with the typical locations of osteoporotic fractures, characterized by a vertebral crushing due to the collapse of vertebral walls. This methodology could be applied for an individual patient, in order to obtain the trends corresponding to different treatments, in identifying at-risk individuals in early stages of osteoporosis and might be helpful for treatment decisions.

Behavior in vitro of the dentin-enamel junction in human premolars submitted to high temperatures: prediction of the maximum temperature based on logistic regression analysis

OBJECTIVE

The aim of the study was to provide scientific evidence that would permit DEJ separation to be used as a parameter to estimate the temperature to which burnt, carbonized or incinerated cadavers or human remains had been subjected.

MATERIALS AND METHODS

A descriptive pseudo-experimental study was carried out in vitro using cone beam tomography to determine the physical behavior of the dentine-enamel junction in 60 human premolars submitted to high temperatures (200°C, 400°C, 600°C, 800°C and 1000°C).

RESULTS

Spearman's concordance and correlation index was used to determine the relationship between longitudinal separation of the dentine-enamel junction (mm) and temperature (°C) and a simple linear regression model developed to show that once micro- and macrostructural changes are initiated in the enamel and dentine.

CONCLUSIONS

The dentine-enamel junction begins to separate from the cervical towards the occlusal as temperature increases.

Is personality relevant in the choice of bleaching?

OBJECTIVES

The purpose was to administer the NEO-FFI personality test to patients who did and did not want to have their teeth bleached and before and after bleaching to the participants who accepted the treatment. The research question is to correlate styles and personality factors with bleaching.

MATERIALS AND METHODS

There were 128 patients eligible for bleaching; 58 accepted (AB) while 70 refused (RB). The test was administered to both groups (AB-RB). The group AB was administered before and 1 week after the end of the bleaching. For each personality domain comparison, the Mann-Whitney test was used. For the group AB, the results for each domain before and after bleaching were compared using the Wilcoxon test.

RESULTS

There was a significant difference between the groups (AB-RB) in the extraversion factor (p = 0.01). There was no significant difference between any of the personality items before and after bleaching (p > 0.1). The comparison between groups by sex revealed significant differences in extraversion and neuroticism factors. Males who AB scored higher in extraversion than males who RB (p < 0.05). Females scored higher in neuroticism than males who AB (p < 0.05).

CONCLUSIONS

There were personality differences between people who decided to bleach compared with those who did not want the bleaching, which was mainly in the extroversion factor. This stereotypes the patients, who could be described as more sociable, extroverted, and concerned about esthetics and cleanliness. The bleaching protocol, however, cannot modify any of the personality factors.

CLINICAL SIGNIFICANCE

It is important to understand a patient's behavior to meet their needs and to determine the type of patients who would like to have their teeth bleached.

The emerging role of Snail1 in the tumor stroma

The transcription factor Snail1 leads to the epithelial-mesenchymal transition by repressing the adherent and tight junctions in epithelial cells. This process is related to an increase of cell migratory and mesenchymal properties during both embryonic development and tumor progression. Although Snail1 expression is very limited in adult animals, emerging evidence has placed Snail at the forefront of medical science. As a transcriptional repressor, Snail1 confers cancer stem cell-like traits on tumor cells and promotes drug resistance, tumor recurrence and metastasis. In this review, we summarize recent reports that suggest the pro-tumorigenic roles of Snail1 expression in tumor stroma. The crosstalk between tumor and stromal cells mediated by Snail1 regulates paracrine communication, pro-tumorigenic abilities of cancer cells, extracellular matrix characteristics and mesenchymal differentiation in cancer stem cells and cancer-associated fibroblasts. Therefore, understanding the regulation and functional roles of Snail1 in the tumor microenvironment will provide us with new therapies for treating metastatic disease.

[Rivaroxaban versus standard of care in venous thromboembolism prevention following hip or knee arthroplasty in daily clinical practice (Spanish data from the international study XAMOS)]

OBJECTIVE

To analyse the effectiveness and safety of rivaroxaban vs. standard treatment (ST) in the prevention of venous thromboembolism after hip or knee replacement in daily clinical practice in Spain.

MATERIAL AND METHOD

A sub-analysis of the Spanish data in the XAMOS international observational study that included patients>18 years who received 10mg o.d. rivaroxaban or ST.

FOLLOW-UP

up to 3 months after surgery.

PRIMARY OUTCOMES

incidence of symptomatic/asymptomatic thromboembolic events, bleeding, mortality, and other adverse events;

SECONDARY OUTCOMES

use of health resources and satisfaction after hospital discharge.

RESULTS

Of the total 801 patients included, 410 received rivaroxaban and 391 ST (64.7% heparin, 24.0% fondaparinux, 11% dabigatran). The incidence of symptomatic thromboembolic events and major bleeding was similar in both groups (0.2% vs. 0.8% wit ST and 0.7% vs. 1.3% with ST [EMA criteria]/0.0% vs. 0.3% with ST [RECORD criteria]). The adverse events incidence associated with the drug was significantly higher rivaroxaban (overall: 4.4% vs. 0.8% with ST, P=.001; serious: 1.5% vs. 0.0% with ST, P=.03). The rivaroxaban used less health resources after discharge, and the majority considered the tolerability as «very good« and the treatment as «very comfortable».

DISCUSSION

Rivaroxaban is at least as effective as ST in the prevention of venous thromboembolism prevention in daily clinical practice, with a similar incidence of haemorrhages. It provides greater satisfaction/comfort, and less health resources after discharge. These results should be interpreted taking into account the limitations inherent in observational studies.

Anxiolytic-Like Effects of 7H-Benzo[e]perimidin-7-One Derivatives through Elevated Plus-Maze Test in Mice

Anxiety is one of the behavior disorders that has been studied more together with depression in the world, and that has enormous interference in the mental health of the affected patients. The states of panic and phobia are a part of the psychological characteristics that some drugs have tried to control though with varied side effects that are proven to be difficult to control. The use of perimidinone derivatives against the effects of anxiety has generated that A5 is the most active and selective anxiolytic compound, differing with regard to diazepam (DZP) used as control reference in elevated plus-maze (EPM) test. This test allows to conclude that it is feasible to differentiate the use selective as anxiolytic or antidepressant of certain perimidinones, because A4 had been characterized by our research group as an important antidepressant respect to A5 studied in previous reports.