bluuebunny/crossref_metadata_2025 huggingface dataset:
Multi-degree-of-freedom vibration reduction strategy of the solar array drive system
Authors: Shi-Yao Zhu , Dong-Xu Li , Yong-Jun Lei
Published: May 2021

The operation disturbance induced by the solar array drive system (SADS) and the residual vibration of solar array following the attitude adjustment of the spacecraft obviously affect the dynamics environment, quick stabilization, and attitude stability of the high-precision spacecraft. However, these two kinds of vibration disturbance are characterized by distinct vibration categories, direction of vibration, and modal shapes. A multi-degree-of-freedom vibration reduction strategy (VRS) was presented to improve the dynamic characteristics of SADS and then to weaken these disturbances synthetically in this paper. SADS applying this VRS was modeled based on the virtual work principle, and the influence of the stiffness and damping parameters of this VRS on the SADS dynamic characteristics was analyzed. Then a prototype of vibration reduction device (VRD) was designed and verified by disturbance characteristic and modal experiments. The results indicate that the equivalent stiffness of VRD is critical to the natural frequency of SADS and thus should be carefully deliberated to avoid resonance. The equivalent damping of VRD always has positive correlation with modal damping. A good performance up to 40% in terms of operation disturbance suppression and a greater than 56% decrease of the damping time for 99% residual vibration have been obtained.
Experimental study on the dynamic behaviour of drones designed for racing competitions
Authors: Castiblanco Jose M , Garcia-Nieto S , Simarro R , Salcedo JV
Published: May 2021

Drones designed for racing usually feature powerful miniaturised electronics embedded in fairly light and strong geometric composite structures. The main objective of this article is to analyse the behaviour of various models of racing drones and their geometrical structures (airframes). Two approaches have been made: (i) an analysis of the information collected by a set of speed and time sensors located on an indoor race track and using a statistical technique (box and whiskers diagram) and (ii) an analysis of the know-how (flight sensations) of a group of racing pilots using a series of technical interviews on the behaviour of their drones. By contrasting these approaches, it has been possible to validate numerically the effects of varying the arm angles, as well as lengths, on a test race track and relate the geometry of these structures to racing behaviour.
Modeling of a controlled flow cup for improved transitional drinking development in children
Authors: Bailey-Van Kuren Michael M , Scarborough Donna
Published: May 2021

Introduction

Clinical observations of children with swallowing disorders using a traditional “sippy” or transitional drinking cup identified a need for a novel cup. Children with swallowing disorders are often unable to initiate the forces required to activate the cup and/or maintain suction pressure. Furthermore, fast flow rates can result in choking.

Methods

A new cup design tool is proposed using fluid-cup interactions to capture the changing geometry of the fluid during drinking. A Petri net formulation is integrated with standard fluid flow principles. A new parametric cup simulation provides visualization and direct implementation for microcontroller prototypes. A vent-based controller is developed and modeled for a novel transitional drinking cup design. A simulated pouring study is performed for water and a baseline liquid volume of 200 ml in the cup. The study varies rotation rates, initial volume, system control and desired flow rates.

Results

Volumetric flow rate curves over time are generated and compared in relation to a target flow rate. The simulation results show expected behavior for variations in cup parameters.

Conclusion

The new simulation model facilitates future dysphagia research through rapid prototyping by tuning cup geometry, liquid parameters and control signals to meet the varying needs of the users.
Expert Technique: Pediatric Tracheal Surgery
Authors: Stephens Elizabeth H. , Wiedermann Joshua P. , Dearani Joseph A. , Backer Carl L.
Published: May 2021

Substantial improvements in techniques of tracheal surgery for children have occurred in the past 20 years. Precise preoperative imaging with computed tomography clearly defines the anatomy for surgical planning and is assisted by on-the-table needle localization. The use of cardiopulmonary bypass greatly facilitates creation of an airtight, widely patent trachea. The use of Ciprodex as a postoperative nebulizer has significantly decreased granulation tissue along the suture line. Most important has been the adoption of slide tracheoplasty as the procedure of choice.
Transplantation for Congenital Heart Disease: Focus on the Impact of Functionally Univentricular Versus Biventricular Circulation
Authors: Riggs Kyle W. , Broderick John T. , Price Nina , Chin Clifford , Zafar Farhan , Morales David L. S.
Published: May 2021

Background:

Varying single center data exist regarding the posttransplant outcomes of patients with single ventricle circulation, particularly following the Fontan operation. We sought to better elucidate these results in patients with congenital heart disease (CHD) through combining two national databases.

Methods:

The United Network for Organ Sharing (UNOS) transplantation database was merged with the Pediatric Health Information System (PHIS), an administrative database with 71% of UNOS patients matched. Patients undergoing transplantation at a PHIS hospital from 2006 to 2017 were categorized as single ventricle or biventricular strategy based on their diagnoses and procedures in 90% of patients. When known, single ventricle patients were further analyzed by their palliative stage post-Glenn or post-Fontan (known in 31%).

Results:

A total of 1,517 CHD transplantations were identified, 67% with single ventricle strategy (1,016). Single ventricle, biventricular, and indeterminate patients had similar survival (log-rank P > .1). Risk factors for mortality in patients with CHD were extracorporeal membrane oxygenation (ECMO) support at transplant (hazard: 2.27), ABO blood type incompatibility (hazard: 1.61), African American recipient (hazard 1.42), and liver dysfunction (hazard 1.29). A total of 130 confirmed Fontan and 185 confirmed bidirectional Glenn patients underwent transplantation, each with survival equivalent to biventricular patients (log-rank P > .500). For Fontan patients, renal dysfunction (hazard: 5.40) and transplant <1 year after Fontan (hazard 2.82) were found to be associated with mortality.

Conclusions:

Single ventricle patients, as a group, experience similar outcomes as biventricular patients with CHD undergoing transplantation, and this extends to Fontan patients. Risk factors for mortality correlate with end-organ dysfunction as well as race and ABO blood type incompatibility in the CHD population.
Factors Affecting Health-Related Quality of Life After the Arterial Switch Operation
Authors: Cleuziou Julie , Huber Anna-Katharina , Strbad Martina , Ono Masamichi , Hager Alfred , Hörer Jürgen , Lange Rüdiger
Published: May 2021

Background:

Long-term morbidity and mortality outcomes of the arterial switch operation (ASO) in patients with transposition of the great arteries and Taussig-Bing anomaly are excellent. With an increasing number of patients reaching adolescence and adulthood, more attention is directed toward quality of life. Our study aimed to determine the health-related quality of life (hrQoL) outcomes in patients after the ASO and identify factors influencing their hrQoL.

Methods:

In this cross-sectional study, hrQoL of patients after ASO was assessed with the German version of the Short Form-36 (SF-36) and the potential association of specified clinical factors was analyzed. Patients of at least 14 years of age who underwent ASO in our institution from 1983 were considered eligible.

Results:

Of the 355 questionnaires sent to eligible patients, 261 (73%) were available for analysis. Compared to the reference population, patients who had undergone ASO had a significantly higher score in all subscales of the SF-36 except for vitality ( P < .01). Patients with an implanted pacemaker ( P = .002), patients who required at least one reoperation ( P < .001), and patients currently taking cardiac medication ( P < .004) or oral anticoagulation ( P = .036) had lower physical component scores compared to patients without these factors.

Conclusions:

Patients’ self-assessed and self-reported hrQoL after ASO (using German version of the Short Form 36) is very good. In this population, hrQoL is influenced by reoperation, the need for a pacemaker, and current cardiac medication or anticoagulant use. The development of strategies designed to mitigate or minimize the requirements for, and/or impact of these factors may lead to better hrQoL in this patient population.
Teachers’ Perception of Their Code-Switching Practices in English as a Foreign Language Classes: The Results of Stimulated Recall Interview and Conversation Analysis
Authors: Zainil Yetti , Arsyad Safnil
Published: May 2021

Teachers often code-switch in the EFL classroom, but the question of whether or not they are aware of their code-switching has not been satisfactorily answered. This article presents the study on teachers’ understandings and beliefs about their code-switching practices in EFL classrooms as well as effective language teaching and learning. The participants of this study came from four junior high schools in Padang, West Sumatra, Indonesia: five teachers with their respective classes. This research used the conversation analysis and stimulated recall interviews to analyze the data which came from the video recording of classroom observations and the audio recording of stimulated recall interviews with teachers. The results revealed the pedagogical functions and affective functions of teacher’s code-switching. The data also showed that the use of stimulated recall interviews helped teachers to be consciously aware of their code-switching as well as of their other pedagogical practices in the language classroom. Therefore, stimulated recall interviews can be a useful tool for teacher self-reflection that they were not aware of their code switch. This awareness could be incorporated into language teacher professional development and in-service teacher professional learning.
Assessment of Young People’s Motivation for Pursuit of Higher Degree in the Field of Education: Implications for Educational Philosophy and Teacher Policy in Nigeria
Authors: Ugwuozor Felix Okechukwu , Ngwoke Dominic U.
Published: May 2021

This study assesses students’ motivation for the pursuit of higher degree in the field of Education. Due to their current low-income status (mean value of less than $2 day) and their desired income (mean value of $500 per day) 10 years after acquiring the degree, it is instructive and tractable to examine the income effect of their motivation. Their current low-income status suggests that they are on the average, meeting basic needs such as food and clothing. In addition, their desired income suggests that they desire to possibly move up the zenith of the hierarchies of need. Thus, current income, desired income, choice to work in the educational sector, intended career destination, and (revealed) altruistic motive for teaching in primary and secondary schools after moving up in the ladder of needs were measures of motivation and dependent variables. Ordinary least squares (OLS) and discrete choice models were estimated to identify the determinants of these measures. Results show that very few students had wanted to study Education at undergraduate level. Motivation for their enrolment in postgraduate education, however, is apparently pecuniary and essentially market driven. Most of the students preferred high-paying professions within the education sector—lectureship positions in the tertiary institutions, influencing policies as politicians and political appointees, and running educational businesses. Although, a few students intended to teach in future at the basic level, primary and secondary levels, most of them possess altruistic motives to teach, that is, to mentor students.
Revision Arthroscopic Bankart Repair Versus Arthroscopic Latarjet for Failed Primary Arthroscopic Stabilization With Subcritical Bone Loss
Authors: Calvo Emilio , Luengo Gonzalo , Morcillo Diana , Foruria Antonio M. , Valencia María
Published: May 2021

Background:

Limited evidence is available regarding the recommended technique of revision surgery for recurrent shoulder instability. Only 1 previous study has compared the results of soft tissue repair and the Latarjet technique in patients with persistent shoulder instability after primary surgical stabilization.

Purpose/Hypothesis:

To evaluate the results of revision surgery in patients with previous surgical stabilization failure and subcritical glenoid bone defects, comparing repeated Bankart repair versus arthroscopic Latarjet technique. The hypothesis was that Latarjet would be superior to soft tissue procedures in terms of objective and subjective functional scores, recurrence rates, and range of movement.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

Included were 45 patients (mean age, 29.1 ± 8.9 years) with subcritical bone loss (<15% of articular surface) who had undergone revision anterior shoulder instability repair after failed Bankart repair. Of these, 17 patients had arthroscopic Bankart repair and 28 had arthroscopic Latarjet surgery. Patients were evaluated at a minimum of 2 years postoperatively with the Rowe score, Western Ontario Shoulder Instability Index, and Subjective Shoulder Value. Subluxation or dislocation episodes were considered failures.

Results:

No statistically significant differences were found between groups in age, sex, sporting activity, preoperative Rowe score, or the presence of hyperlaxity or bony lesions. At revision arthroscopy, 20 shoulders showed a persistent Bankart lesion, 13 a medially healed labrum, and 6 a bony Bankart. In 6 patients, no abnormalities were present that could explain postoperative recurrence. In the Bankart repair group, 7 patients underwent isolated Bankart procedures; in the remaining 10 cases, a capsular shift was added. No significant differences were found between the Bankart and Latarjet groups in outcome scores, recurrence rate (11.8% vs 17.9%, respectively), or postoperative athletic activity level. The mean loss of passive external rotation at 0° and 90° of abduction was similar between groups.

Conclusion:

Arthroscopic Latarjet did not lead to superior results compared with repeated Bankart repair in patients with subcritical glenoid bone loss and recurrent anterior shoulder instability after Bankart repair.
The Phenotypic Spectrum of Tuberous Sclerosis Complex: A Canadian Cohort
Authors: Alsowat Daad , Whitney Robyn , Hewson Stacy , Jain Puneet , Chan Valerie , Kabir Nadia , Amburgey Kimberly , Noone Damien , Lemaire Mathieu , McCoy Blathnaid , Zak Maria
Published: May 2021

Objective:

We aimed to further elucidate the phenotypic spectrum of Tuberous Sclerosis Complex (TSC) depending on genotype.

Methods:

A retrospective review of patients seen in the TSC clinic at the Hospital for Sick Children was conducted and the frequency of TSC manifestations was compared based on genotype.

Results:

Nineteen-patients had TSC1 mutations, 36 had TSC2 mutations and 11 had no mutation identified (NMI). Patients with TSC2 mutations had a higher frequency of early-onset epilepsy and more frequent systemic manifestations. The NMI group had milder neurologic and systemic manifestations. Our data did not demonstrate that intellectual disability and infantile spasms were more common in TSC2 mutations.

Conclusions:

This is the first Canadian pediatric cohort exploring the genotype-phenotype relationship in TSC. We report that some manifestations are more frequent and severe in TSC2 mutations and that NMI may have a milder phenotype. Disease surveillance and counseling should continue regardless of genotype until this is better elucidated.
Bridging the Telemedicine Gap Among Seniors During the COVID-19 Pandemic
Authors: Utley Lynn M , Manchala Grace S , Phillips Mark J , Doshi Chirag P , Szatalowicz Victoria L , Boozer Jennifer R
Published: May 2021

At the onset of the COVID-19 pandemic, many senior patients in the USC-Keck Family Medicine clinics were limited or lacking in telemedicine participation. Three factors contributed: lack of video-enabled devices, technological literacy, and/or absence of Wi-Fi connectivity. We addressed the first 2 of these factors. Via phone contact, 9 patients agreed to receive donated Android or Apple devices and to trial instruction manuals for use. Donated equipment and instructions were prepared and delivered in accordance with pandemic guidelines. Follow-up calls indicated that 4 participants were able to set up their devices and 3 of whom had connected with their providers. The remaining 5 participants had not set up their devices by the end of the follow-up period, had difficulty with device setup, accessing applications necessary for telemedicine, or had limited access to Wi-Fi. This project highlights some telemedicine barriers that senior patients may overcome with the additional support of care providers.
Vasculature in the Margin of the Psoriatic Lesion
Authors: Hanssen Sabina C. A. , Seyger Marieke M. B. , van Erp Piet E. J. , der Vleuten Catharina J. M. van , de Kerkhof Peter C. M. van
Published: May 2021

Background:

Factors initiating capillary conversion in the immunopathogenesis of psoriasis are not well established and quantification of vascular changes in- and outside visible psoriatic plaque has not been studied extensively.

Objectives:

To assess the pathological involvement of capillaries in the context of well-established features of psoriasis in different phases: symptomless psoriatic skin distant from a lesion (SDL), adjacent to a lesion (SAL), the margin zone of the lesion (ML) and the center of the psoriatic lesion (CL).

Methods:

In 10 patients with chronic plaque psoriasis, and 10 healthy matched controls, vascular parameters (vascular tonicity (VD), vascular surface area (VAR), microvascular density (MVD), angiogenesis (pEC)) and hypoxia in the context of well-established features (keratinocyte proliferation, neutrophils and T-cells) were analyzed within the psoriatic lesion and symptomless psoriatic skin, using immunohistochemical markers (Ki67/CD31 double-staining and HIF-1α-, Elastase- and T-Bet-staining).

Results:

VD and neutrophils were significantly increased in all sites, compared to healthy controls. The VAR, MVD, Ki67+ nuclei, HIF-1α and T-Bet start to augment in the SAL. Within the overt psoriatic plaque angiogenesis increases. Biopsies closer to the center of a plaque, exhibited increased values of the MVD, VAR, VD, Ki67+ nuclei, T-Bet+ Th1 cells and neutrophils.

Conclusion:

In SDL, vasodilatation and activation of the innate immune system (increased neutrophils) was detected. This could indicate that psoriasis is not restricted to lesional skin, but rather is a systemic disease. Closer to the psoriatic plaque, vascular and epithelial proliferation was observed, along with hypoxic cells and activation of the acquired immunity (augmented T-Bet cells).
SLAP Tears
Authors: Cohen Steven B. , Matthews John R.
Published: May 2021

Background:

Superior labral tears are frequently encountered during shoulder arthroscopy. Outcomes following superior labral anterior-posterior (SLAP) repairs in young athletes have been well documented. Superior labral repairs in older patient population continue to remain controversial due to concerns of postoperative complications including persistent preoperative symptoms, pain, stiffness, and higher rates of revision surgery.

Indications:

We present a case of a highly active 38-year-old woman who failed 1½ years of nonoperative management of a type IIB SLAP tear with extension to the posterior labrum. Her symptoms continued to limit her hobbies and work.

Technique:

A knotless single-anchor SLAP repair was performed along with debridement of the posterior frayed labrum. No biceps tenotomy or tenodesis was performed after full evaluation of the tendon failed to demonstrate evidence of synovitis, tendinopathy, or tear. The patient also did not have any concomitant shoulder pathology, including a rotator cuff tear or chondral lesion.

Results:

At 6 months, the patient had regained full range of motion similar to the contralateral side. She had returned to her normal activities and sports, including tennis.

Discussion/Conclusion:

Successful outcomes following SLAP repairs in patients over 35 years can be achieved, but treatment should be individualized with particular attention to concomitant pathology involving the rotator cuff, chondral surface, or biceps tendon which may require tenodesis or tenotomy.
Water immersion tolerance by larval instars of stable fly, Stomoxys calcitrans, L1758 (Diptera: Muscidae) impairs the fitness performance of their subsequent stages
Authors: Baleba Steve B. S.
Published: May 2021

Background

In holometabolous insects, environmental factors experienced in pre-imaginal life stages affect the life-history traits within that stage and can also influence subsequent life stages. Here, I assessed tolerance to water immersion by the larval instars of the stable fly, Stomoxys calcitrans L. (Diptera: Muscidae) and its impact on the life-history traits of their subsequent life stages.

Results

After submerging the three larval instars of S. calcitrans in distilled water, I found that the first instar larvae remained active for longer as compared to the second and third instar larvae. Also, the first instar larvae took a longer period to recover from the stress-induced immobility when removed from the water and returned to ambient temperature. When I followed the development of individuals of each larval instar that survived from water immersion, I found that their developmental time, weight, pupation percentage, adult emergence percentage and adult weight were negatively affected by this stressor. However, the weight of S. calcitrans adults developed from immersed first larval instar individuals was not affected by water immersion whereas their counterparts developed from immersed second and third larval instars had lower body weight. This suggests that in S. calcitrans, water immersion stress at the earlier stage is less detrimental than that experienced at late stages.

Conclusion

This study provides a comparative overview of the fitness consequences associated with water immersion stress during S. calcitrans larval ontogeny. The results prove that the fitness shift induced by water immersion in S. calcitrans is stage-specific. My results illustrate the importance of considering each larval instar when assessing the impact of environmental factors on holometabolous insect performance as these may be decoupled by metamorphosis.
Salivary testing of COVID-19: evaluation of serological testing following positive salivary results
Authors: Caulley Lisa , Shaw Julie , Corsten Martin , Hua Nadia , Angel Jonathan B. , Poliquin Guillaume , Whelan Jonathan , Antonation Kym , Johnson-Obaseki Stephanie
Published: May 2021

Background

Salivary detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been proposed as an alternative to nasopharyngeal or oropharyngeal swab testing. Our group previously published a study demonstrating that both testing methods identified SARS-CoV-2 using polymerase chain reaction (PCR)-based detection methodology. We therefore conducted a follow-up study using antibody testing to evaluate the accuracy of saliva versus swabs for COVID-19 detection and the durability of antibody response.

Methods

Venous blood samples were collected from consenting participants and the presence of serum antibodies for SARS-CoV-2 was evaluated on a large, automated immunoassay platform by the Roche anti-SARS-CoV-2 qualitative assay (Roche Diagnostics, Laval Quebec). Individuals with a serum antibody cut-off index (COI) ≥ 1.0 were considered positive.

Results

In asymptomatic and mildly symptomatic patients with a previously positive standard swab and/or saliva SARS-CoV-2 PCR-test, 42 demonstrated antibodies with 13 patients positive by swab alone, and 8 patients positive by saliva alone.

Conclusions

Despite their status as ‘current standard’ for COVID-19 testing, these findings highlight limitations of PCR-based tests.
Laboratory analysis and ray visualization of diffractive optics with enhanced intermediate vision
Authors: Son Hyeck-Soo , Łabuz Grzegorz , Khoramnia Ramin , Yildirim Timur M. , Auffarth Gerd U.
Published: May 2021

Background

To assess the optical behavior of a new diffractive intraocular lens (IOL) and compare its performance to that of an established extended-depth-of-focus (EDOF) IOL.

Methods

This study assessed the Proming EDOF Multifocal AM2UX [Eyebright Medical Technology (Beijing) Co., Ltd., China] and the AT LARA 829MP [Carl Zeiss Meditec, Germany]. An experimental set-up with 0.01% fluorescein solution and monochromatic light (532 nm) was used to visualize the IOLs’ ray propagation. In addition, the optical quality of the IOLs was assessed by measuring the modulation transfer function (MTF) values at 50lp/mm and 3.0 and 4.5 mm apertures on the optical bench OptiSpheric® IOL PRO II [Trioptics GmbH, Germany].

Results

The ray propagation of the two IOLs showed two distinct foci. Light intensity assessment revealed that both IOLs allocate more energy to primary than secondary focus. At 3.0 mm pupil, the MTF values at 50lp/mm for the primary focus were 0.39 and 0.37, and for the secondary focus, 0.29 and 0.26 for the AT LARA and Proming IOLs, respectively. At 4.5 mm pupil, the single-frequency MTF for the primary focus was 0.51 and 0.24 and for the secondary focus 0.21 and 0.15 for the AT LARA and Proming IOLs, respectively.

Conclusions

When tested with an aberration-free model cornea under monochromatic conditions, the Proming behaved as a low-add bifocal lens; however, its properties did not differ much from the well-established AT LARA EDOF IOL. The AT LARA outperformed the Proming at low defocus (up to 2D), while the latter demonstrated better image quality in the 2-3D range.
Fidelity to an evidence-based model for crisis resolution teams: a cross-sectional multicentre study in Norway
Authors: Hasselberg N. , Holgersen K. H. , Uverud G. M. , Siqveland J. , Lloyd-Evans B. , Johnson S. , Ruud T.
Published: May 2021

Background

Crisis resolution teams (CRTs) are specialized multidisciplinary teams intended to provide assessment and short-term outpatient or home treatment as an alternative to hospital admission for people experiencing a mental health crisis. In Norway, CRTs have been established within mental health services throughout the country, but their fidelity to an evidence-based model for CRTs has been unknown.

Methods

We assessed fidelity to the evidence-based CRT model for 28 CRTs, using the CORE Crisis Resolution Team Fidelity Scale Version 2, a tool developed and first applied in the UK to measure adherence to a model of optimal CRT practice. The assessments were completed by evaluation teams based on written information, interviews, and review of patient records during a one-day visit with each CRT.

Results

The fidelity scale was applicable for assessing fidelity of Norwegian CRTs to the CRT model. On a scale 1 to 5, the mean fidelity score was low (2.75) and with a moderate variation of fidelity across the teams. The CRTs had highest scores on the content and delivery of care subscale, and lowest on the location and timing of care subscale. Scores were high on items measuring comprehensive assessment, psychological interventions, visit length, service users’ choice of location, and of type of support. However, scores were low on opening hours, gatekeeping acute psychiatric beds, facilitating early hospital discharge, intensity of contact, providing medication, and providing practical support.

Conclusions

The CORE CRT Fidelity Scale was applicable and relevant to assessment of Norwegian CRTs and may be used to guide further development in clinical practice and research. Lower fidelity and differences in fidelity patterns compared to the UK teams may indicate that Norwegian teams are more focused on early interventions to a broader patient group and less on avoiding acute inpatient admissions for patients with severe mental illness.
Stable osteosynthesis of cage in cage technique for surgical treatment of proximal humeral fractures
Authors: Li Jiantao , Gao Yuan , Yin Caixia , Zhang Hao , Nie Shaobo , Guo Hui , Quan Chenliang , Chen Hua , Zhang Wei
Published: May 2021

Background

The treatment of a displaced proximal humeral fracture is still a matter of controversy. The purpose of this study was to report outcomes at a long-term follow-up after fixation augmentation using peek (polyether-ether-ketone) cage and locking compression plate (LCP).

Methods

A total of 27 patients (average age 53.8 years, range 19–86 years) were treated with peek cage and LCP. All of them had a minimum radiographic and clinical follow-up of 1 years. Outcomes were assessed using the Constant-Murley score (CMS), disability of the arm, shoulder and hand (DASH) score. Complications were also recorded during follow-up.

Results

The average follow-up was 28 months (range 12–48 months). The mean functional outcomes were as follows: CMS, 73.3 (range 61–86); DASH, 45.9 (range 27–68). A total of 4 patients had complications: osteonecrosis developed in one patient, loss of reduction was observed in 1 patient and stiffness was occurred in two patients.

Conclusion

The use of peek cage and LCP has been a valuable option in the treatment of proximal humeral fractures. The complication rate was acceptable. Suitable void filler in the proximal humerus for reconstructing the medial column integrity attains mechanical stability in reducing the incidence of the complications.
Vincetoxicum arnottianum modulates motility features and metastatic marker expression in pediatric rhabdomyosarcoma by stabilizing the actin cytoskeleton
Authors: Adamus Anna , Ali Iftikhar , Vasileiadis Vasileios , Al-Hileh Luai , Lisec Jan , Frank Marcus , Seitz Guido , Engel Nadja
Published: May 2021

Background

Prevention of metastatic invasion is one of the main challenges in the treatment of alveolar rhabdomyosarcoma. Still the therapeutic options are limited. Therefore, an anti-tumor screening was initiated focusing on the anti-metastatic and anti-invasion properties of selected medicinal plant extracts and phytoestrogens, already known to be effective in the prevention and treatment of different cancer entities.

Methods

Treatment effects were first evaluated by cell viability, migration, invasion, and colony forming assays on the alveolar rhabdomyosarcoma cell line RH-30 in comparison with healthy primary cells.

Results

Initial anti-tumor screenings of all substances analyzed in this study, identified the plant extract of Vincetoxicum arnottianum (VSM) as the most promising candidate, harboring the highest anti-metastatic potential. Those significant anti-motility properties were proven by a reduced ability for migration (60%), invasion (99%) and colony formation (61%) under 48 h exposure to 25 μg/ml VSM. The restricted motility features were due to an induction of the stabilization of the cytoskeleton – actin fibers were 2.5-fold longer and were spanning the entire cell. Decreased proliferation (PCNA, AMT, GCSH) and altered metastasis (e. g. SGPL1, CXCR4, stathmin) marker expression on transcript and protein level confirmed the significant lowered tumorigenicity under VSM treatment. Finally, significant alterations in the cell metabolism were detected for 25 metabolites, with levels of uracil, N-acetyl serine and propanoyl phosphate harboring the greatest alterations. Compared to the conventional therapy with cisplatin, VSM treated cells demonstrated a similar metabolic shutdown of the primary cell metabolism. Primary control cells were not affected by the VSM treatment.

Conclusions

This study revealed the VSM root extract as a potential, new migrastatic drug candidate for the putative treatment of pediatric alveolar rhabdomyosarcoma with actin filament stabilizing properties and accompanied by a marginal effect on the vitality of primary cells.

Graphical abstract
“I’ll just deal with this on my own”: a qualitative exploration of experiences with self-managed abortion in the United States
Authors: Raifman Sarah , Ralph Lauren , Biggs M. Antonia , Grossman Daniel
Published: May 2021

Background

A growing body of evidence indicates that some people seek options to terminate a pregnancy without medical assistance, but experiences doing so have largely been documented only among people accessing a clinic-based abortion. We aim to describe self-managed abortion (SMA) experiences of people recruited outside of clinics, including their motivations for SMA, pregnancy confirmation and decision-making processes, method choices, and clinical outcomes.

Methods

In 2017, we conducted 14 in-depth interviews with self-identified females of reproductive age who recently reported in an online survey administered to Ipsos’KnowledgePanelthat, since 2000, they had attempted SMA while living in the United States. We asked participants about their reproductive histories, experiences seeking reproductive health care, and SMA experiences. We used an iterative process to develop codes and analyzed transcripts using thematic content analysis methods.

Results

Motivations and perceptions of effectiveness varied by whether participants had confirmed the pregnancy prior to SMA. Participants who confirmed their pregnancies chose SMA because it was convenient, accessible, and private. Those who did not test for pregnancy were motivated by a preference for autonomy and felt empowered by the ability to try something on their own before seeking facility-based care. Participants prioritized methods that were safe and available, though not always effective. Most used herbs or over-the-counter medications; none used self-sourced abortion medications, mifepristone and/or misoprostol. Five participants obtained facility-based abortions and one participant decided to continue the pregnancy after attempting SMA. The remaining eight reported being no longer pregnant after SMA. None of the participants sought care for  SMA complications; one participant saw a provider to confirm abortion completion.

Conclusions

There are many types of SMA experiences. In addition to those who pursue SMA as a last resort (after facing barriers to facility-based care) or as a first resort (because they prefer homeopathic remedies), our findings show that some individuals view SMA as a potential interim step worth trying after suspecting pregnancy and before accessing facility-based care. These people in particular would benefit from a medication abortion product available over the counter, online, or in the form of a missed-period pill.
Excellent option for mass testing during the SARS-CoV-2 pandemic: painless self-collection and direct RT-qPCR
Authors: Kriegova Eva , Fillerova Regina , Raska Milan , Manakova Jirina , Dihel Martin , Janca Ondrej , Sauer Pavel , Klimkova Martina , Strakova Petra , Kvapil Petr
Published: May 2021

The early identification of asymptomatic yet infectious cases is vital to curb the 2019 coronavirus (COVID-19) pandemic and to control the disease in the post-pandemic era. In this paper, we propose a fast, inexpensive and high-throughput approach using painless nasal-swab self-collection followed by direct RT-qPCR for the sensitive PCR detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This approach was validated in a large prospective cohort study of 1038 subjects, analysed simultaneously using (1) nasopharyngeal swabs obtained with the assistance of healthcare personnel and analysed by classic two-step RT-qPCR on RNA isolates and (2) nasal swabs obtained by self-collection and analysed with direct RT-qPCR. Of these subjects, 28.6% tested positive for SARS-CoV-2 using nasopharyngeal swab sampling. Our direct RT-qPCR approach for self-collected nasal swabs performed well with results similar to those of the two-step RT-qPCR on RNA isolates, achieving 0.99 positive and 0.98 negative predictive values (cycle threshold [Ct] < 37). Our research also reports on grey-zone viraemia, including samples with near-cut-off Ct values (Ct ≥ 37). In all investigated subjects (n = 20) with grey-zone viraemia, the ultra-small viral load disappeared within hours or days with no symptoms. Overall, this study underscores the importance of painless nasal-swab self-collection and direct RT-qPCR for mass testing during the SARS-CoV-2 pandemic and in the post-pandemic era.
Resilience and related factors as predictors of relapse risk in patients with substance use disorder: a cross-sectional study
Authors: Yamashita Ayako , Yoshioka Shin-ichi , Yajima Yuki
Published: May 2021

Background

Resilience, referring to the inherent ability to naturally recover in the face of adverse conditions, is an essential concept in discussions of substance use disorder (SUD) recovery. This study’s objective was to shed light on resilience and related factors that affect relapse risk in patients with SUDs.

Method

Fifty-two patients with SUDs were given a self-administrated questionnaire from February to April 2015 consisting of question items for sociodemographic characteristics, relapse risk (Stimulant Relapse Risk Scale), and resilience (Bidimensional Resilience Scale). Scale scores were tested for associations with subject attributes, after which resilience’s effects on relapse risk were analyzed using correlation and multiple regression (forced-entry) analyses.

Results

Stimulants were the most common substance related to SUD (n = 26, 21.7%; multiple answers). Bivariate correlation showed that higher acquired resilience was significantly associated with a lower relapse risk (r = − 0.314, P < 0.01). Reduced relapse risk was significantly associated with current employment (Std. β = − 0.446, P < 0.05).

Conclusion

Our findings demonstrate the necessity of recovery support to enhance acquired resistance in patients with SUDs to prevent relapses. Reinforcing employment support services and encouraging patients to continue treatment were suggested as potentially effective measures to enhance resilience in individuals with SUDs on their road to recovery.
Increasing lipid yield in Yarrowia lipolytica through phosphoketolase and phosphotransacetylase expression in a phosphofructokinase deletion strain
Authors: Kamineni Annapurna , Consiglio Andrew L. , MacEwen Kyle , Chen Shuyan , Chifamba Gamuchirai , Shaw A. Joe , Tsakraklides Vasiliki
Published: May 2021

Background

Lipids are important precursors in the biofuel and oleochemical industries. Yarrowia lipolytica is among the most extensively studied oleaginous microorganisms and has been a focus of metabolic engineering to improve lipid production. Yield improvement, through rewiring of the central carbon metabolism of Y. lipolytica from glucose to the lipid precursor acetyl-CoA, is a key strategy for achieving commercial success in this organism.

Results

Building on YB-392, a Y. lipolytica isolate known for stable non-hyphal growth and low citrate production with demonstrated potential for high lipid accumulation, we assembled a heterologous pathway that redirects carbon flux from glucose through the pentose phosphate pathway (PPP) to acetyl-CoA. We used phosphofructokinase (Pfk) deletion to block glycolysis and expressed two non-native enzymes, phosphoketolase (Xpk) and phosphotransacetylase (Pta), to convert PPP-produced xylulose-5-P to acetyl-CoA. Introduction of the pathway in a pfk deletion strain that is unable to grow and accumulate lipid from glucose in defined media ensured maximal redirection of carbon flux through Xpk/Pta. Expression of Xpk and Pta restored growth and lipid production from glucose. In 1-L bioreactors, the engineered strains recorded improved lipid yield and cell-specific productivity by up to 19 and 78%, respectively.

Conclusions

Yields and cell-specific productivities are important bioprocess parameters for large-scale lipid fermentations. Improving these parameters by engineering the Xpk/Pta pathway is an important step towards developing Y. lipolytica as an industrially preferred microbial biocatalyst for lipid production.
Complete remission of advanced low-grade endometrial stromal sarcoma after aromatase inhibitor therapy: a case report
Authors: Altal Omar F. , Al Sharie Ahmed H. , Halalsheh Omar M. , Tashtush Nour , Shaban Sarat , Alfaqih Mahmoud , Aleshawi Abdelwahab
Published: May 2021

Background

Low-grade endometrial stromal sarcoma is a rare neoplastic growth in the uterine cavity, representing less than 1% of uterine tumors. Such tumors usually affect premenopausal and perimenopausal women, with a mean age of 46 years. Treatment generally starts with surgical resection of the tumor, followed by chemotherapy, radiotherapy, or hormonal therapy.

Case presentation

In the current report, we again present a case of low-grade endometrial stromal sarcoma in a 51-year-old Mediterranean woman presenting with abdominopelvic pain. Computed tomography scan revealed a primary uterine tumor measuring 17 × 9 × 9 cm metastasizing to the lungs, bladder, and ureteral orifice, along with lymphovascular involvement. The patient underwent total abdominal hysterectomy, omentectomy, and lymph node dissection. Estrogen deprivation was accomplished by bilateral salpingo-oophorectomy. Lifelong hormonal therapy consisting of letrozole 2.5 mg per day was prescribed, which demonstrated remarkable efficacy, resulting in a partial remission of lung metastasis within 8 months after surgery. Full remission was observed after 18 months of hormonal therapy, with no recurrence. Another scan was performed after 2.5 years, revealing complete remission with no recurrence.

Conclusion

We again report a case of complete remission of low-grade endometrial stromal sarcoma after surgical removal of the tumor along with first-line hormonal therapy without the use of chemotherapy or radiotherapy, emphasizing the role of hormonal therapy in the treatment of such tumors.
Low-dose IL-34 has no effect on osteoclastogenesis but promotes osteogenesis of hBMSCs partly via activation of the PI3K/AKT and ERK signaling pathways
Authors: Xu Jianxiang , Fu Lifeng , Bai Jinwu , Zhong Huiming , Kuang Zhihui , Zhou Chengwei , Hu Bin , Ni Licheng , Ying Li , Chen Erman , Zhang Wei , Wu Jiaqi , Xue Deting , Li Weixu , Pan Zhijun
Published: May 2021

Background

Inflammatory microenvironment is significant to the differentiation and function of mesenchymal stem cells (MSCs). It evidentially influences the osteoblastogenesis of MSCs. IL-34, a newly discovered cytokine, playing a key role in metabolism. However, the research on its functional role in the osteogenesis of MSCs was rarely reported. Here, we described the regulatory effects of low-dose IL-34 on both osteoblastogenesis and osteoclastogenesis.

Methods

We performed the osteogenic effects of hBMSCs by exogenous and overexpressed IL-34 in vitro, so were the osteoclastogenesis effects of mBMMs by extracellular IL-34. CCK-8 was used to assess the effect of IL-34 on the viability of hBMSCs and mBMMs. ALP, ARS, and TRAP staining was used to evaluate ALP activity, mineral deposition, and osteoclastogenesis, respectively. qRT-PCR and Western blotting analysis were performed to detect the expression of target genes and proteins. ELISA was used to evaluate the concentrations of IL-34. In vivo, a rat tibial osteotomy model and an OVX model were established. Radiographic analysis and histological evaluation were performed to confirm the therapeutic effects of IL-34 in fracture healing and osteoporosis. Statistical differences were evaluated by two-tailed Student’s t test, one-way ANOVA with Bonferroni’s post hoc test, and two-way ANOVA with Bonferroni multiple comparisons post hoc test in the comparison of 2 groups, more than 2 groups, and different time points of treated groups, respectively.

Results

Promoted osteoblastogenesis of hBMSCs was observed after treated by exogenous or overexpressed IL-34 in vitro, confirmed by increased mineral deposits and ALP activity. Furthermore, exogenous or overexpressed IL-34 enhanced the expression of p-AKT and p-ERK. The specific AKT and ERK signaling pathway inhibitors suppressed the enhancement of osteoblastogenesis induced by IL-34. In a rat tibial osteotomy model, imaging and histological analyses testified the local injection of exogenous IL-34 improved bone healing. However, the additional IL-34 has no influence on both osteoclastogenesis of mBMMs in vitro and osteoporosis of OVX model of rat in vivo.

Conclusions

Collectively, our study demonstrate that low-dose IL-34 regulates osteogenesis of hBMSCs partly via the PIK/AKT and ERK signaling pathway and enhances fracture healing, with neither promoting nor preventing osteoclastogenesis in vitro and osteoporosis in vivo.
High-resolution spatiotemporal pHe and pO2 imaging in head and neck and oesophageal carcinoma cells
Authors: Blancke Soares Alexandra , Meier Robert , Liebsch Gregor , Schwenk-Zieger Sabina , Kirmaier Martin E. , Theurich Sebastian , Widmann Magdalena , Canis Martin , Gires Olivier , Haubner Frank
Published: May 2021

Background

pO2 and pH are physiological parameters relevant for different processes in health and disease, including wound healing and cancer progression. Head and neck squamous cell carcinomas (HNSCC) and oesophageal squamous cell carcinomas (ESCC) have a high rate of local recurrence that is partly related to treatment-resistant residual tumour cells. Hence, novel diagnostic tools are required to visualise potential residual tumour cells and thereby improve treatment outcome for HNSCC and ESCC patients. We developed a device to spatiotemporally measure oxygen consumption rates (OCR) and extracellular acidification rates (ECAR) to distinguish HNSCC and ESCC cells from healthy cells in vitro, exploiting general metabolic differences between cancer cells and healthy cells.

Methods

OCR and ECAR were measured via a newly developed device named STO2p-Q (SpatioTemporal O2 and pH Quantification) using the VisiSens technology based on ratiometric fluorescence imaging, facilitating spatiotemporal resolution. Results were confirmed using extracellular flux analyses (Seahorse technology).

Results

STO2p-Q is described and used to measure OCR and ECAR in HNSCC and ESCC cell lines and normal fibroblast and epithelial cells as components of the tumour microenvironment. OCR measurements showed differences amongst HNSCC and ESCC cell lines and between HNSCC/ESCC and normal cells, which on average had lower OCR than HNSCC/ESCC cells. Both OCR and ECAR measurements were independently verified using the Seahorse technology. Additionally, using STO2p-Q, HNSCC/ESCC, and normal cells could be spatially resolved with a resolution in the low millimetre range.

Conclusions

We developed a method to spatiotemporally measure OCR and ECAR of cells, which has many potential in vitro applications and lays the foundation for the development of novel diagnostic tools for the detection of cancerous tissue in HNSCC and ESCC patients in vivo.