bluuebunny/crossref_metadata_2025 huggingface dataset:
Lung-protective ventilation increases cerebral metabolism and non-inflammatory brain injury in porcine experimental sepsis
Authors: Nyberg Axel , Gremo Erik , Blixt Jonas , Sperber Jesper , Larsson Anders , Lipcsey Miklós , Pikwer Andreas , Castegren Markus
Published: April 2021

Background

Protective ventilation with lower tidal volumes reduces systemic and organ-specific inflammation. In sepsis-induced encephalopathy or acute brain injury the use of protective ventilation has not been widely investigated (experimentally or clinically). We hypothesized that protective ventilation would attenuate cerebral inflammation in a porcine endotoxemic sepsis model. The aim of the study was to study the effect of tidal volume on cerebral inflammatory response, cerebral metabolism and brain injury. Nine animals received protective mechanical ventilation with a tidal volume of 6 mL × kg−1 and nine animals were ventilated with a tidal volume of 10 mL × kg−1. During a 6-h experiment, the pigs received an endotoxin intravenous infusion of 0.25 µg × kg−1 × h−1. Systemic, superior sagittal sinus and jugular vein blood samples were analysed for inflammatory cytokines and S100B. Intracranial pressure, brain tissue oxygenation and brain microdialysis were sampled every hour.

Results

No differences in systemic or sagittal sinus levels of TNF-α or IL-6 were seen between the groups. The low tidal volume group had increased cerebral blood flow (p < 0.001) and cerebral oxygen delivery (p < 0.001), lower cerebral vascular resistance (p < 0.05), higher cerebral metabolic rate (p < 0.05) along with higher cerebral glucose consumption (p < 0.05) and lactate production (p < 0.05). Moreover, low tidal volume ventilation increased the levels of glutamate (p < 0.01), glycerol (p < 0.05) and showed a trend towards higher lactate to pyruvate ratio (p = 0.08) in cerebral microdialysate as well as higher levels of S-100B (p < 0.05) in jugular venous plasma compared with medium–high tidal volume ventilation.

Conclusions

Contrary to the hypothesis, protective ventilation did not affect inflammatory cytokines. The low tidal volume group had increased cerebral blood flow, cerebral oxygen delivery and cerebral metabolism together with increased levels of markers of brain injury compared with medium–high tidal volume ventilation.
The Selvester QRS score as an estimative of myocardial injury in acute chagasic patients from the Brazilian Amazon
Authors: do Nascimento Couceiro Katia , Ortiz Jessica Vanina , do Nascimento Correia Michael , da Silva e Silva Mônica Regina Hosannah , Brandão Alba Regina , da Silva Paula Rita Leite , Doria Susan Smith , Bestetti Reinaldo Bulgarelli , de Sousa Débora Raysa Teixeira , da Silva Junior Rubens Celso Andrade , das Graças Vale Barbosa Guerra Maria , Ferreira João Marcos Bemfica Barbosa , de Oliveira Guerra Jorge Augusto
Published: April 2021

Background

In the Brazilian Amazon, a new epidemiological profile of Chagas disease transmission, the oral route, has been detected and cited as being responsible for the increase in acute cases in Brazil. The clinical evaluation of acute Chagas disease (ACD) has been a challenge since it can progress to a chronic phase with cardiac alterations, and the follow-up by modern diagnostic methods is very difficult due to the socio-geographical characteristics of the Brazilian Amazon. Thus, alternatives should be sought to alleviate this problem. We conducted a study to evaluate subjects with ACD using the 12-lead ECG QRS score (Selvester score) as an estimative of myocardial injury progression before and after ACD treatment.

Methods

The study included indigenous subjects from the Amazon region with ACD in clinical follow-up at the Fundação de Medicina Tropical Dr. Heitor Vieira Dourado (FMT-HVD) Chagas Disease outpatient clinic in the state of Amazonas, Brazil. The control group consisted of 31 healthy volunteers with no history of heart disease and no reactive serology for Chagas disease. Baseline ECG was performed in all subjects. The Selvester scoring method was performed according to the standardized guide (< 3 points: no myocardial injury,> 3: points × 3% = % of the predicted LV infarction).

Results

A total of 62 subjects were included, 31 as cases and 31 as controls. The mean follow-up of the case group was 17 months. The control group presented normal ECG. The case group presented 13 alterations before treatment and 11 after. Nineteen individuals presented scores > 3 points, 6 before and 13 after. In 19.36% of subjects, myocardial injury was found before treatment and in 41.94% after treatment.

Conclusion

This is the first study that uses the Selvester score (SS) to predict myocardial injury in subjects with ACD. The results of this study suggest the significant presence of myocardial injury from the beginning of treatment to the period post treatment of ACD, which demonstrates that the SS can be applied for stratification and follow-up of Chagas disease in the Amazon region.
Age-based targeting of biannual azithromycin distribution for child survival in Niger: an adaptive cluster-randomized trial protocol (AVENIR)
Authors:   the AVENIR Study Group, O’Brien Kieran S. , Arzika Ahmed M. , Amza Abdou , Maliki Ramatou , Ousmane Sani , Kadri Boubacar , Nassirou Beido , Mankara Alio Karamba , Harouna Abdoul Naser , Colby Emily , Lebas Elodie , Liu Zijun , Le Victoria , Nguyen William , Keenan Jeremy D. , Oldenburg Catherine E. , Porco Travis C. , Doan Thuy , Arnold Benjamin F. , Lietman Thomas M.
Published: April 2021

Background

Biannual distribution of azithromycin to children 1–59 months old reduced mortality by 14% in a cluster-randomized trial. The World Health Organization has proposed targeting this intervention to the subgroup of children 1–11 months old to reduce selection for antimicrobial resistance. Here, we describe a trial designed to determine the impact of age-based targeting of biannual azithromycin on mortality and antimicrobial resistance.

Methods

AVENIR is a cluster-randomized, placebo-controlled, double-masked, response-adaptive large simple trial in Niger. During the 2.5-year study period, 3350 communities are targeted for enrollment. In the first year, communities in the Dosso region will be randomized 1:1:1 to 1) azithromycin 1–11: biannual azithromycin to children 1–11 months old with placebo to children 12–59 months old, 2) azithromycin 1–59: biannual azithromycin to children 1–59 months old, or 3) placebo: biannual placebo to children 1–59 months old. Regions enrolled after the first year will be randomized with an updated allocation based on the probability of mortality in children 1–59 months in each arm during the preceding study period. A biannual door-to-door census will be conducted to enumerate the population, distribute azithromycin and placebo, and monitor vital status. Primary mortality outcomes are defined as all-cause mortality rate (deaths per 1000 person-years) after 2.5 years from the first enrollment in 1) children 1–59 months old comparing the azithromycin 1–59 and placebo arms, 2) children 1–11 months old comparing the azithromycin 1–11 and placebo arm, and 3) children 12–59 months in the azithromycin 1–11 and azithromycin 1–59 arms. In the Dosso region, 50 communities from each arm will be followed to monitor antimicrobial resistance. Primary resistance outcomes will be assessed after 2 years of distributions and include 1) prevalence of genetic determinants of macrolide resistance in nasopharyngeal samples from children 1–59 months old, and 2) load of genetic determinants of macrolide resistance in rectal samples from children 1–59 months old.

Discussion

As high-mortality settings consider this intervention, the results of this trial will provide evidence to support programmatic and policy decision-making on age-based strategies for azithromycin distribution to promote child survival.

Trial registration

This trial was registered on January 13, 2020 (clinicaltrials.gov:NCT04224987).
Combination therapies with thiazolidinediones are associated with a lower risk of acute exacerbations in new-onset COPD patients with advanced diabetic mellitus: a cohort-based case–control study
Authors: Chen Kuan-Yuan , Wu Sheng-Ming , Tseng Chien-Hua , Lee Kang-Yun , Lin Yu-Huei , Liu Hung-Yi , Chien Li-Nien
Published: April 2021

Background

The effects of oral antihyperglycaemic drugs (OADs) for type 2 diabetes mellitus (T2DM) on the outcomes of co-existing chronic obstructive pulmonary disease (COPD) patients are not well studied. We examined the association of combinational OADs and the risk of acute exacerbations of COPD (AECOPD) in T2DM patients with co-existing COPD.

Methods

A cohort-based case–control study was conducted using data from the National Health Insurance Research Database of Taiwan. Among new-onset COPD-T2DM patients, 65,370 were prescribed metformin and 2nd-line OADs before the date of COPD onset. Each AECOPD case was matched to 4 randomly selected controls according to the propensity score estimated by the patient’s baseline characteristics. Conditional logistic regression analysis was performed to estimate the association between AECOPD risk and OAD use.

Results

Among COPD-T2DM patients, 3355 AECOPD cases and 13,420 matched controls were selected. Of the patients treated with a double combination of oral OADs (n = 12,916), those treated with sulfonylurea (SU) and thiazolidinediones (TZD) had a lower AECOPD risk than the patients who received metformin (MET) and SU, with an adjusted odds ratio (OR) of 0.69 (95% confidence interval [CI] 0.51–0.94,P = 0.02). Of the patients with a triple combination of oral OADs (n = 3859), we found that those treated with MET, SU and TZD had a lower risk of AECOPD (adjusted OR 0.81 (0.68–0.96,P = 0.01) than a combination of MET, SU and α-glucosidase inhibitors (AGIs) regardless of the level of COPD complexity.

Conclusion

Combination therapies with TZD were associated with a reduced risk of AECOPD in advanced T2DM patients with co-existing COPD.
Esophageal leiomyoma and simultaneous overlying squamous cell carcinoma: a case report and review of the literature
Authors: Mehrabi Saadat , Yavari Barhaghtalab Mohammad Javad , Hejazinia Safoora , Saedi Hossein
Published: April 2021

Background

Squamous cell carcinoma is the most common epithelial tumor of the esophagus. Upper endoscopy with multiple minimally invasive biopsies should be performed to confirm the diagnosis. Leiomyoma of esophagus is rare, but it’s the most common benign submucosal mesenchymal tumor of the esophagus. The simultaneous occurrence of an overlying epithelial lesion and a mesenchymal lesion is very rare. This study aims to show a case operated due to squamous cell carcinoma of esophagus that was postoperatively diagnosed with coexistent esophageal leiomyoma and give a clear overview of the existing literature on it.

Case presentation

The patient was a 41-year-old woman who underwent three field esophagectomy (McKeown). Pathological evaluation was done, and the patient had poorly differentiated squamous cell carcinoma and multiple leiomyomas. A leiomyoma was found with an invading overlying squamous cell carcinoma.

Conclusion

It is concluded that esophageal carcinomas may coexist with leiomyomas; preexisting benign tumors may have played an important role in the development of the carcinoma by inducing constant stimulation of the overlying mucosa; endoscopic ultrasonography is recommended to avoid overestimating the extent of tumor invasion and the resultant aggressive radical surgery. As the developing countries had limited equipment, esophageal resection could be the modality of choice in the treatment.
Association of hypertension and incident diabetes in Chinese adults: a retrospective cohort study using propensity-score matching
Authors: Wu Yang , Hu Haofei , Cai Jinlin , Chen Runtian , Zuo Xin , Cheng Heng , Yan Dewen
Published: April 2021

Background

Reliable quantification of the relationship between hypertension and diabetes risk is limited, especially among Chinese people. We aimed to investigate the association between hypertension and the risk of diabetes in a large cohort of the Chinese population.

Methods

This was a retrospective propensity score-matched cohort study among 211,809 Chinese adults without diabetes at baseline between 2010 and 2016. The target independent and dependent variable were hypertension at baseline and incident diabetes during follow-up respectively. The propensity score matching using a non-parsimonious multivariable logistic regression was conducted to balance the confounders between 28,711 hypertensive patients and 28,711 non-hypertensive participants. The doubly robust estimation method was used to investigate the association between hypertension and diabetes.

Results

In the propensity-score matching cohort, diabetes risk increased by 11.0% among hypertensive patients (HR = 1.110, 95% confidence interval (CI): 1.031–1.195, P = 0.00539). And diabetes risk dropped to 8.3% among hypertensive subjects after adjusting for the propensity score (HR = 1.083, 95%CI: 1.006–1.166, P = 0.03367). Compared to non-hypertensive participants with low propensity score, the risk of incident diabetes increased by 2.646 times among hypertensive patients with high propensity score (HR = 3.646, 95%CI: 2.635–5.045, P < 0.0001).

Conclusion

Hypertension was associated with an 11.0% increase in the risk of developing diabetes in Chinese adults. And the figure dropped to 8.3% after adjusting the propensity score. Additionally, compared to non-hypertensive participants with low propensity scores, the risk of incident diabetes increased by 2.646 times among hypertensive patients with high propensity scores.
Effects of Green cardamom (Elettaria cardamomum Maton) and its combination with cyclophosphamide on Ehrlich solid tumors
Authors: Almeer Rafa S. , Alnasser Meshael , Aljarba Nada , AlBasher Gadah I.
Published: April 2021

Background

Cardamom (Elettaria cardamomum) is a spice and exhibits potent antioxidant and biological activities through distinct molecular mechanisms. However, the anticancer effect of cardamom was not explored yet in Ehrlich solid tumor (EST)-bearing mice.

Objectives

This investigation was aimed to evaluate the anti-cancer effects of green cardamom (GCar) alone or combined with the anti-cancer drug cyclophosphamide in an in vivo model to explore its mechanistic role in tumor cell death in EST-bearing mice.

Methods

Ehrlich ascites tumor cells were injected in the mice and 5 days later the animals treated with GCar and/or cyclophosphamide for 10 days. Twenty-four hours from the last treatment, animals were sacrificed for the different measurements.

Results

Data recorded for tumor size, percentage of tumor growth inhibition, tumor growth delay and mean survival time of EST-bearing mice demonstrated the effective role of GCar alone or combined with CPO as a promising anti-cancer agent because it reduced tumor size. GCar elevated the mean survival time of EST-bearing mice compared to that of untreated EST and EST + CPO groups. Analysis of qPCR mRNA gene and protein expression revealed that GCar alone or combined with CPO were promising anticancer agents. After the treatment of EST with GCar, the apoptotic-related genes and proteins were significantly modulated. GCar induced markedly significant decreases in oxidative stress biomarkers and a significant increment in glutathione levels and that of antioxidant enzymes. With a marked diminish in liver and kidney function biomarkers.

Conclusion

The results revealed that GCar could serve as an apoptotic stimulator agent, presenting a novel and potentially curative approach for cancer treatment, inducing fewer side effects than those of the commercially used anti-cancer drugs, such as CPO.
Ethical and procedural issues for applying researcher-driven multi-national paediatric clinical trials in and outside the European Union: the challenging experience of the DEEP project
Authors: Giannuzzi Viviana , Felisi Mariagrazia , Bonifazi Donato , Devlieger Hugo , Papanikolaou George , Ragab Lamis , Fattoum Slaheddine , Tempesta Bianca , Reggiardo Giorgio , Ceci Adriana
Published: April 2021

Background

We describe our experience from a multi-national application of a European Union-funded research-driven paediatric trial (DEEP-2, EudraCT 2012-000353-31; NCT01825512). This paper aims to evaluate the impact of the local and national rules on the trial authorisation process in European and non-European countries. National/local provisions and procedures, number of Ethics Committees and Competent Authorities to be addressed, documentation required, special provisions for the paediatric population, timelines for completing the authorisation process and queries received were collected; compliance with the European provisions were evaluated. Descriptive analysis, Wilcoxon Rank-Sum test and General Linear Model analysis were used to determine factors potentially influencing the timelines. The Cluster Analysis procedure was used to identify homogenous groups of cases.

Result

The authorisation process was completed in 7.7 to 53.8 months in European countries and in 17.1 to 27.1 months in non-European countries. The main factors influencing these timelines were the requests for changes/clarifications in European countries and the different national legislations in non-European countries.

Conclusion

This work confirms that the procedures and requirements for the clinical trial application of a paediatric trial are different. In the European Union, the timeframes for submission were generally harmonised but longer. In non-European countries, delays were caused by national dispositions but the entire authorisation process resulted faster with less requests from ECs/CAs. The upcoming application of Regulation (EU) 536/2014 is expected to harmonise practices in Europe and possibly outside. Networks on paediatric research acting at international level will be crucial in this effort.
“From experts to locals hands” healthcare service planning in sub-Saharan Africa: an insight from the integrated community case management of Ghana
Authors: Annobil Isaac , Dakyaga Francis , Sillim Mavis Lepiinlia
Published: April 2021

Background

Although community participation remains an essential component globally in healthcare service planning, evidence of how rural communities participate in the planning of rural-based healthcare programs has less been explored in Sub-Saharan Africa.

Objective

We explored communities’ participation in health care planning in hard-to-reach communities, within the context of Integrated Community Case Management (iCCM), a community-based health program implemented in Ghana.

Methods

Qualitative data were collected from eleven (11) hard-to-reach communities through Focus Group Discussions (FGDs), Key Informant Interviews (KIIs) as well as district-level studies (Nadowli-Kaleo, and WA East districts of Ghana). The Rifkin’s spider-gram, framework, for measuring and evaluating community participation in healthcare planning was adapted for the study.

The results

The study found that community participation was superficially conducted by the CHOs. A holistic community needs assessment to create awareness, foster a common understanding of health situations, collaboration, acceptance and ownership of the program were indiscernible. Rather, it took the form of an event, expert-led-definition, devoid of coherence to build locals understanding to gain their support as beneficiaries of the program. Consequently, some of the key requirements of the program, such as resource mobilization by rural residents, Community-based monitoring of the program and the act of leadership towards sustainability of the program were not explicitly found in the beneficiaries’ communities.

Conclusion and recommendation

The study concludes that there is a need to expand the concept of community involvement in iCCM to facilitate communities’ contribution to their healthcare. Also, a transdisciplinary approach is required for engineering and scaling up community-based health programs, empowering VHCs, CBHVs and CHAs to realize success.
Upper eyelid blepharoplasty following hyaluronic acid injection with improved facial aesthetics and eye symptoms: a case report
Authors: Maione Luca , Vinci Valeriano , Costanzo Domenico , Battistini Andrea , Lisa Andrea , Di Maria Alessandra
Published: April 2021

Background

Dermatochalasis of the upper eyelids (blepharochalasis) is a typical age-related change in the upper third of the face and a major concern for facial aesthetics. Nowadays both surgical and nonsurgical interventions are available for patients complaining of upper eyelid dermatochalasis. Although nonsurgical treatments are often easier to perform, if they are not performed correctly, complications may ensue and worsen the condition.

Case presentation

We describe the case of a Caucasian patient presenting with bilateral upper eyelid dermatochalasis, previously treated with multiple injections of hyaluronic acid filler. Following these procedures, the patient reported nonspecific eye symptoms (such as a sense of heaviness and asthenopia) and cosmetic concerns. We decided to perform an upper eyelid blepharoplasty. During the procedure we found a ribbon of hard, fibrous material, which was carefully removed. The patient reported resolution of functional eye symptoms owing to the reduction of upper lid heaviness, which also resulted in subjective improvement of the visual field. Patient satisfaction was assessed preoperatively and 3 months postoperatively using the Blepharoplasty Outcomes Evaluation (BOE), which showed an overall satisfaction rate of 95.8 %.

Conclusions

Blepharoplasty not only treated the patient’s blepharochalasis but also allowed us to correct the previous nonsurgical intervention by removing the excessive amount of injected hyaluronic acid. Both aesthetic and functional results were successfully achieved.
Doctors' identity and barriers to seeking care when unwell
Authors: Gerada Clare
Published: April 2021

Doctors have a deep-rooted sense of professional identity ‘the medical self’. This allows them to do the jobs society expects from them, but also acts as a barrier when seeking care when unwell. This article discusses how the medical self is formed drawing on psychoanalytic, anthropological and psychiatric literature.
Local NF-κB Activation Promotes Parathyroid Hormone Synthesis and Secretion in Uremic Patients
Authors: Mao Jianping , Wang Mengjing , Ni Li , Gong Wen , Jiang Xinxin , Zhang Qian , Zhang Minmin , Wen Donghai , Chen Jing
Published: April 2021

Secondary hyperparathyroidism (SHPT) in uremic patients is characterized by parathyroid gland (PTG) hyperplasia and parathyroid hormone (PTH) elevation. Previously, we demonstrated that NF-κB activation contributed to parathyroid cell proliferation in rats with chronic kidney disease. Although vitamin D inhibits inflammation and ameliorates SHPT, the contribution of vitamin D deficiency to SHPT via local NF-κB activation remains to be clarified. PTGs collected from 10 uremic patients with advanced SHPT were used to test the expressions of vitamin D receptor (VDR), NF-κB, and proliferating cell nuclear antigen (PCNA). Freshly excised PTG tissues were incubated for 24 hours in vitro with VDR activator (VDRA) calcitriol or NF-κB inhibitor pyrrolidine thiocarbamate (PDTC). Chromatin immunoprecipitation (ChIP) and luciferase reporter assays were performed to investigate the regulation of PTH transcription by NF-κB. We found higher levels of activated NF-κB and lower expression of VDR in nodular hyperplastic PTGs than in diffuse hyperplasia. In cultured PTG tissues, treatment with VDRA or PDTC inhibited NF-κB activation and PCNA expression, and downregulated preproPTH mRNA and intact PTH levels. ChIP assays demonstrated the presence of NF-κB binding sites in PTH promoter. Furthermore, in luciferase reporter assays, addition of exogenous p65 significantly increased PTH luciferase activity by 2.4-fold (P < 0.01), while mutation of NF-κB binding site at position −908 of the PTH promoter suppressed p65-induced PTH reporter activity (P < 0.01). In summary, local NF-κB activation contributes to SHPT and mediates the transcriptional activation of PTH directly in uremic patients. Vitamin D deficiency may be involved in SHPT via the activation of NF-κB pathway.
The Black Aquatic
Authors: Walcott Rinaldo
Published: April 2021

This essay argues that thinking through black diasporic life as birthed through a unique and ongoing relationship with bodies of water (sea, oceans, rivers, creeks) can and does aid in analyses of contemporary art and its engagement with black subjectivity. I am concerned with how bodies of water are foundationally formative of blackness. And secondarily I pursue how this foundational aspect of blackness is both an act of representation worth engaging contemporary art and also a limit on what some representations of contemporary art can do to undo the brutal history of the aquatic birth of blackness and its perpetuation.
Special report of the RSNA COVID-19 task force: systematic review of outcomes associated with COVID-19 neuroimaging findings in hospitalized patients
Authors: Mogensen Monique A. , Wangaryattawanich Pattana , Hartman Jason , Filippi Christopher G. , Hippe Daniel S. , Cross Nathan M. ,   RSNA COVID-19 task force
Published: April 2021

Objective:

We reviewed the literature to describe outcomes associated with abnormal neuroimaging findings among adult COVID-19 patients.

Methods:

We performed a systematic literature review using PubMed and Embase databases. We included all studies reporting abnormal neuroimaging findings among hospitalized patients with confirmed COVID-19 and outcomes. Data elements including patient demographics, neuroimaging findings, acuity of neurological symptoms and/or imaging findings relative to COVID-19 onset (acute, subacute, chronic), and patient outcomes were recorded and summarized.

Results:

After review of 775 unique articles, a total of 39 studies comprising 884 COVID-19 patients ≥ 18 years of age with abnormal neuroimaging findings and reported outcomes were included in our analysis. Ischemic stroke was the most common neuroimaging finding reported (49.3%, 436/884) among patients with mortality outcomes data. Patients with intracranial hemorrhage (ICH) had the highest all-cause mortality (49.7%, 71/143), followed by patients with imaging features consistent with leukoencephalopathy (38.5%, 5/13), and ischemic stroke (30%, 131/436). There was no mortality reported among COVID-19 patients with acute disseminated encephalomyelitis without necrosis (0%, 0/8) and leptomeningeal enhancement alone (0%, 0/12). Stroke was a common acute or subacute neuroimaging finding, while leukoencephalopathy was a common chronic finding.

Conclusion:

Among hospitalized COVID-19 patients with abnormal neuroimaging findings, those with ICH had the highest all-cause mortality; however, high mortality rates were also seen among COVID-19 patients with ischemic stroke in the acute/subacute period and leukoencephalopathy in the chronic period.

Advances in knowledge:

Specific abnormal neuroimaging findings may portend differential mortality outcomes, providing a potential prognostic marker for hospitalized COVID-19 patients.
Metal artefact reduction in the oral cavity using deep learning reconstruction algorithm in ultra-high-resolution computed tomography: a phantom study
Authors: Sakai Yuki , Kitamoto Erina , Okamura Kazutoshi , Tatsumi Masato , Shirasaka Takashi , Mikayama Ryoji , Kondo Masatoshi , Hamasaki Hiroshi , Kato Toyoyuki , Yoshiura Kazunori
Published: April 2021

Objectives:

This study aimed to improve the impact of the metal artefact reduction (MAR) algorithm for the oral cavity by assessing the effect of acquisition and reconstruction parameters on an ultra-high-resolution CT (UHRCT) scanner.

Methods:

The mandible tooth phantom with and without the lesion was scanned using super-high-resolution, high-resolution (HR), and normal-resolution (NR) modes. Images were reconstructed with deep learning-based reconstruction (DLR) and hybrid iterative reconstruction (HIR) using the MAR algorithm. Two dental radiologists independently graded the degree of metal artefact (1, very severe; 5, minimum) and lesion shape reproducibility (1, slight; 5, almost perfect). The signal-to-artefact ratio (SAR), accuracy of the CT number of the lesion, and image noise were calculated quantitatively. The Tukey-Kramer method with a p-value of less than 0.05 was used to determine statistical significance.

Results:

The HRDLR visual score was better than the NRHIR score in terms of degree of metal artefact (4.6 ± 0.5 and 2.6 ± 0.5, p < 0.0001) and lesion shape reproducibility (4.5 ± 0.5 and 2.9 ± 1.1, p = 0.0005). The SAR of HRDLR was significantly better than that of NRHIR (4.9 ± 0.4 and 2.1 ± 0.2, p < 0.0001), and the absolute percentage error of the CT number in HRDLR was lower than that in NRHIR (0.8% in HRDLR and 23.8% in NRIR). The image noise of HRDLR was lower than that of NRHIR (15.7 ± 1.4 and 51.6 ± 15.3, p < 0.0001).

Conclusions:

Our study demonstrated that the combination of HR mode and DLR in UHRCT scanner improved the impact of the MAR algorithm in the oral cavity.
El huerto en tiempos de confinamiento. Análisis de una experiencia en formación de profesorado.
Authors:   ,, ,, Ceballos Aranda Marta , Pérez-Bueno Beatriz , Reina Marta , Vílchez José Eduardo
Published: April 2021

La situación de confinamiento motivada por la pandemia por COVID-19 en la primavera de 2020 representó un reto para el desarrollo de la actividad de huerto escolar en la formación inicial de maestros. El objetivo del presente estudio es analizar las diferencias que existen entre el aprendizaje desarrollado mediante un proyecto de huerto por un grupo de 24 estudiantes de Grado de Educación Primaria en situación de confinamiento y otro correspondiente a cursos anteriores, en la situación habitual de no confinamiento. Se utilizaron los cuadernos de huerto como instrumento de recogida de información sobre la experiencia y reflexiones de los estudiantes. Dicha información se registró en una escala de cuatro valores de respuesta (nada-bajo-medio-alto) para su posterior análisis cuantitativo (frecuencias). Además, se solicitó una valoración explícita del uso del huerto con cuatro opciones, comparando igualmente con años anteriores. De los resultados se destaca el aumento de búsqueda activa de información, la implicación espontánea a las familias y una expresión más intensa de emociones. Siguen valorando positivamente el potencial del huerto en educación ambiental y transmisión de valores, pero aumenta su consideración para transmitir contenidos biológicos y disminuye su valoración como recurso para estrategias relacionadas con indagación. Como conclusión, se constata una vez más el potencial didáctico del huerto incluso en las condiciones más adversas.
Latin American and Caribbean teachers’ transition to online teaching during the pandemic: Challenges, Changes and Lessons Learned
Authors: Hordatt Gentles Carol , Haynes-Brown Tashane
Published: April 2021

The forced transition to online teaching during the Covid-19 pandemic has fast-tracked the integration of ICT use by teachers across Latin America and the Caribbean (LAC) . Given the slow adoption of ICT by LAC teachers before the pandemic it is useful to investigate how, why and in what ways, LAC teachers overcame their prior reluctance and resistance to learn and practice digital literacy. Using qualitative interview data from a global report on teachers’ experiences during Covid-19, this paper analyses how the pandemic changed the ways in which 53 teachers from 15 LAC countries think about and use ICT. It suggests their concern for student loss of learning due to school closures empowered them to overcome barriers that normally impede ICT use by teachers. At the same time, initial acceptance of ICT use has wavered due to ongoing widespread challenges with internet connectivity and access. This has implications for what we know about supporting professional development in the use of ICT after Covid-19 and beyond.
Validation testing to determine the sensitivity of lateral flow testing for asymptomatic SARS-CoV-2 detection in low prevalence settings: Testing frequency and public health messaging is key
Authors: Ferguson Jack , Dunn Steven , Best Angus , Mirza Jeremy , Percival Benita , Mayhew Megan , Megram Oliver , Ashford Fiona , White Thomas , Moles-Garcia Emma , Crawford Liam , Plant Tim , Bosworth Andrew , Kidd Michael , Richter Alex , Deeks Jonathan , McNally Alan
Published: April 2021

Lateral flow devices (LFDs) are quickly being implemented for use in large-scale population surveillance programs for SARS-CoV-2 infection in the United Kingdom. These programs have been piloted in city-wide screening in the city of Liverpool and are now being rolled out to support care home visits and the return home of University students for the Christmas break. Here, we present data on the performance of LFDs to test almost 8,000 students at the University of Birmingham between December 2 and December 9, 2020. The performance is validated against almost 800 samples using PCR performed in the University Pillar 2 testing lab and theoretically validated on thousands of Pillar 2 PCR testing results performed on low-prevalence care home testing samples. Our data show that LFDs do not detect infections presenting with PCR Ct values over 29 to 30 as determined using the Thermo Fisher TaqPath asssay. This may be of particular importance in detecting individuals that are either at the early, or late stages of infection, and reinforces the need for frequent, recurrent testing.
Interactions between all pairs of neighboring trees in 16 forests worldwide reveal details of unique ecological processes in each forest, and provide windows into their evolutionary histories
Authors: Wills Christopher , Wang Bin , Fang Shuai , Wang Yunquan , Jin Yi , Lutz James , Thompson Jill , Harms Kyle E. , Pulla Sandeep , Pasion Bonifacio , Germain Sara , Liu Heming , Smokey Joseph , Su Sheng-Hsin , Butt Nathalie , Chu Chengjin , Chuyong George , Chang-Yang Chia-Hao , Dattaraja H. S. , Davies Stuart , Ediriweera Sisira , Esufali Shameema , Fletcher Christine Dawn , Gunatilleke Nimal , Gunatilleke Savi , Hsieh Chang-Fu , He Fangliang , Hubbell Stephen , Hao Zhanqing , Itoh Akira , Kenfack David , Li Buhang , Li Xiankun , Ma Keping , Morecroft Michael , Mi Xiangcheng , Malhi Yadvinder , Ong Perry , Rodriguez Lillian Jennifer , Suresh H. S. , Sun I Fang , Sukumar Raman , Tan Sylvester , Thomas Duncan , Uriarte Maria , Wang Xihua , Wang Xugao , Yao T. L. , Zimmermann Jess
Published: April 2021

When Darwin visited the Galapagos archipelago, he observed that, in spite of the islands’ physical similarity, members of species that had dispersed to them recently were beginning to diverge from each other. He postulated that these divergences must have resulted primarily from interactions with sets of other species that had also diverged across these otherwise similar islands. By extrapolation, if Darwin is correct, such complex interactions must be driving species divergences across all ecosystems. However, many current general ecological theories that predict observed distributions of species in ecosystems do not take the details of between-species interactions into account. Here we quantify, in sixteen forest diversity plots (FDPs) worldwide, highly significant negative density-dependent (NDD) components of both conspecific and heterospecific between-tree interactions that affect the trees’ distributions, growth, recruitment, and mortality. These interactions decline smoothly in significance with increasing physical distance between trees. They also tend to decline in significance with increasing phylogenetic distance between the trees, but each FDP exhibits its own unique pattern of exceptions to this overall decline. Unique patterns of between-species interactions in ecosystems, of the general type that Darwin postulated, are likely to have contributed to the exceptions. We test the power of our null-model method by using a deliberately modified data set, and show that the method easily identifies the modifications. We examine how some of the exceptions, at the Wind River (USA) FDP, reveal new details of a known allelopathic effect of one of the Wind River gymnosperm species. Finally, we explore how similar analyses can be used to investigate details of many types of interactions in these complex ecosystems, and can provide clues to the evolution of these interactions.
Comparative transcriptome analysis reveals key genes potentially related to organic acid and sugar accumulation in loquat
Authors: Yang Jun , Zhang Jing , Niu Xian-Qian , Zheng Xue-Lian , Chen Xu , Zheng Guo-Hua , Wu Jin-Cheng
Published: April 2021

Organic acids and sugars are the primary components that determine the quality and flavor of loquat fruits. In the present study, major organic acids, sugar content, enzyme activities, and the expression of related genes were analyzed during fruit development in two loquat cultivars, ’JieFangZhong’ (JFZ) and ’BaiLi’ (BL). Our results showed that the sugar content increased during fruit development in the two cultivars; however, the organic acid content dramatically decreased in the later stages of fruit development. The differences in organic acid and sugar content between the two cultivars primarily occured in the late stage of fruit development and the related enzymes showed dynamic changes in activies during development. Phosphoenolpyruvate carboxylase (PEPC) and mNAD malic dehydrogenase (mNAD-MDH) showed higher activities in JFZ at 95 days after flowering (DAF) than in BL. However, NADP-dependent malic enzyme (NADP-ME) activity was the lowest at 95 DAF in both JFZ and BL with BL showing higher activity compared with JFZ. At 125 DAF, the activity of fructokinase (FRK) was significantly higher in JFZ than in BL. The activity of sucrose synthase (SUSY) in the sucrose cleavage direction (SS-C) was low at early stages of fruit development and increased at 125 DAF. SS-C activity was higher in JFZ than in BL. vAI and sucrose phosphate synthase (SPS) activities were similar in the two both cultivars and increased with fruit development. RNA-sequencing was performed to determine the candidate genes for organic acid and sugar metabolism. Our results showed that the differentially expressed genes (DEGs) with the greated fold changes in the later stages of fruit development between the two cultivars were phosphoenolpyruvate carboxylase 2 (PEPC2), mNAD-malate dehydrogenase (mNAD-MDH), cytosolic NADP-ME (cyNADP-ME2), aluminum-activated malate transporter (ALMT9), subunit A of vacuolar H+-ATPase (VHA-A), vacuolar H+-PPase (VHP1), NAD-sorbitol dehydrogenase (NAD-SDH), fructokinase (FK), sucrose synthase in sucrose cleavage (SS-C), sucrose-phosphate synthase 1 (SPS1), neutral invertase (NI), and vacuolar acid invertase (vAI). The expression of 12 key DEGs was validated by quantitative reverese transcription PCR (RT-qPCR). Our findings will help understand the molecular mechanism of organic acid and sugar formation in loquat, which will aid in breeding high-quality loquat cultivars.
Effect of O-linked glycosylation on the antigenicity, cellular uptake and trafficking in dendritic cells of recombinant Ber e 1
Authors: Jambari Nuzul N. , Liddell Susan , Martinez-Pomares Luisa , Alcocer Marcos J. C.
Published: April 2021

Ber e 1, a major Brazil nut allergen, has been successfully produced in the yeastPichia pastorisexpression system as homogenous recombinant Ber e 1 (rBer e 1) with similar physicochemical properties and identical immunoreactivity to its native counterpart, nBer e 1. However,O-linked glycans was detected on theP.pastoris-derived rBer e 1, which is not naturally present in nBer e 1, and may contribute to the allergic sensitisation. In this study, we addressed the glycosylation differences betweenP.pastoris-derived recombinant Ber e 1 and its native counterparts. We also determined whether this fungal glycosylation could affect the antigenicity and immunogenicity of the rBer e 1 by using dendritic cells (DC) as an immune cell model due to their role in modulating the immune response. We identified that the glycosylation occurs at Ser96, Ser101 and Ser110 on the large chain and Ser19 on the small polypeptide chain of rBer e 1 only. The glycosylation on rBer e 1 was shown to elicit varying degree of antigenicity by binding to different combination of human leukocyte antigens (HLA) at different frequencies compared to nBer e 1 when tested using human DC-T cell assay. However, both forms of Ber e 1 are weak immunogens based from their low response indexes (RI). Glycans present on rBer e 1 were shown to increase the efficiency of the protein recognition and internalization by murine bone marrow-derived dendritic cells (bmDC) via C-type lectin receptors, particularly the mannose receptor (MR), compared to the non-glycosylated nBer e 1 and SFA8, a weak allergenic 2S albumin protein from sunflower seed. Binding of glycosylated rBer e 1 to MR alone was found to not induce the production of IL-10 that modulates bmDC to polarise Th2 cell response by suppressing IL-12 production and DC maturation. Our findings suggest that theO-linked glycosylation byP.pastorishas a small but measurable effect on thein vitroantigenicity of the rBer e 1 compared to its non-glycosylated counterpart, nBer e 1, and thus may influence its applications in diagnostics and immunotherapy.
Validity concerns with the Revised Study Process Questionnaire (R-SPQ-2F) in undergraduate anatomy & physiology students
Authors: Johnson Staci N. , Gallagher Eliza D. , Vagnozzi Anna Marie
Published: April 2021

The 20-question Revised Study Process Questionnaire (R-SPQ-2F), which is frequently used to categorize student learning approaches as either deep or surface, was administered to three sections of Anatomy & Physiology (A&P) courses at a highest research university in the southeastern United States as part of a larger research project. Two hundred thirty-one (231) respondents completed the full survey and 11 participants were recruited to a comparative case study. Initial review of interview transcripts raised concerns about the validity of the R-SPQ-2F results with the population of interest. Interview transcripts were coded using a priori codes corresponding to the R-SPQ-2F items, and qualitative and quantitative results were then triangulated. Additional survey responses were collected in a subsequent semester and a confirmatory factor analysis (CFA) was performed using the complete responses from 381 students. The CFA yielded similar or better measures of reliability and fit to the two-factor structure as those in previously reported work by other authors. Nonetheless, findings from triangulation suggest that the R-SPQ-2F was not able to group students by deep and surface approaches to learning in the context of an undergraduate A&P course. In addition, six interviews (3 deep, 3 surface) demonstrated a new theme of surface leading to deep with participants indicating that memorization was necessary for the purpose of gaining a full understanding of the course material. This mixed method analysis calls into question whether the results are valid for separating student approaches into the previously published descriptions of deep and surface approaches. The finding of the surface leading to deep orientation, which may align with previous descriptions of an achieving approach, has significant implications for both research and instruction, as memorizing and other “surface” strategies are often minimized and discouraged, yet are an important step in student learning.
Comércio Intra-Indústria
Authors: Afonso Óscar , Pinto Carlos , Vasconcelos Paulo Beleza
Published: April 2021

O modelo do Krugman mostra que o comércio internacional pode surgir e conduzir a ganhos mútuos para os países participantes, mesmo quando são semelhantes em tecnologia e dotações. O comércio intra‑indústria emergente entre países baseia‑se em economias de escala, no intercâmbio de variedades diferenciadas dos produtos produzidos sob a concorrência monopolista e nas preferências heterogéneas. Alargamos o modelo de base, considerando duas configurações dinâmicas, com especial enfoque no lado do produtor. A primeira extensão revela que os ganhos a longo prazo são concomitantes com perdas a curto prazo para os trabalhadores do país mais pequeno devido à diferença de competitividade. Até que o fosso de competitividade seja preenchido, é necessária uma diminuição dos salários nominais ou uma diminuição da taxa de câmbio para que o país mantenha a sua capacidade de produção e uma posição comercial internacional equilibrada. Depois, consideramos que a estrutura de custos de uma indústria também depende de fatores que não podem desvalorizar através da taxa de câmbio. Neste contexto, os trabalhadores de empresas que têm uma desvantagem competitiva, devido a um ponto de partida de baixa eficiência, podem sentir um impacto negativo durante um período de transição, perdendo o poder de compra. Enquanto o país como um todo ganha, alguns agentes dentro do país podem perder, pelo menos a curto prazo. Os resultados são ilustrados numericamente, utilizando o MATLAB, calibrado tendo por base o exemplo em Krugman e Obtsfeld (2006).
Padrões dos IPOs na Euronext Após a Crise Financeira Global de 2007‑2008
Authors: Silva Nuno , Sebastião Helder , Henriques Diogo
Published: April 2021

O presente artigo analisa os padrões de avaliação de 161 IPOs que ocorreram entre 2009 e 2017 nos mercados Euronext de Amesterdão, Bruxelas, Lisboa e Paris. Em média, para todos os IPOs, o primeiro dia do evento apresenta um retorno de 1,4% e um retorno ajustadoao setor de 1,2%. Após um ano, os retornos médios são ligeiramente maiores, cerca de4,5%, enquanto os retornos médios ajustados são negativos, cerca de ‑2,7%.Os retornos doprimeiro dia são menores enquanto os retornos de longo prazo são maiores do que aquelesapresentados noutros estudos, em particular naqueles que consideram um período que sesobrepõe, pelo menos em parte, àquele utilizado na presente análise. O setor dos Cuidadosde Saúde é aquele que apresenta uma maior subavaliação inicial, com um retorno ajustadoao setor de 2,3%, enquanto os IPOs no sector Tecnológico apresentam o pior desempenhoanual, com um retorno ajustado de ‑29,5%.Os resultados suportam as hipóteses de condiçõesde mercado e de sentimento do investidor, de acordo com as quais, quando as condiçõesde mercado são más (crises), os investidores não‑informadosnão são tão ativos e otimistasno mercado dos IPOs, o que resulta numa subavaliação inicial e num subdesempenho delongo prazo menores. Uma explicação possível para estes resultados é que a crise financeiraglobal reduziu persistentemente a atividade e o otimismo dos investidores não‑informadosno mercado de IPOs, mesmo quando o mercado acionista europeu e a economia em geraljá se encontravam numa fase subsequente de recuperação.
Between Theory and Reality: The challenge of distinguishing between trafficked children and independent child migrants
Authors: Dottridge Mike
Published: April 2021

The offence of child trafficking appears to have a clear definition in the UN Trafficking Protocol and in laws based on it. In practice, this is an illusion. This article reviews the experiences of three countries (Benin, the United Kingdom, and Vietnam), in two of which anti-trafficking laws and policies regard a broad swath of children who migrate to earn a living, without being subjected to coercion, as victims of trafficking. It questions whether the definitions in international law and in the laws of many countries of what constitutes the crime of trafficking committed against a child are appropriate to distinguish between adolescent migrants in general and those who are victims of crime (at the hands of a trafficker) in particular. It suggests that this is in part because there is no international understanding about the ages at which children habitually leave home to find work and what should be done to protect them when they do. It concludes that a possible result of considering a very broad range of children to be ‘trafficked’ is that measures to protect and assist those who suffer acute harm are inadequate.