bluuebunny/crossref_metadata_2025_split huggingface dataset:
Impact of COVID-19 on Pathology Presenting to a Foot and Ankle Clinic
Authors: Mehta Nabil , Hur Edward , Michalski Joseph , Fitch Ashlyn , Sayari Arash , Bohl Daniel D. , Holmes George B. 
Published: March 2021

Category: Other Introduction/Purpose: In our city, the COVID-19 pandemic led to a shelter-in-place ordinance, job loss, gym closures, and employees working from home. As a result, individuals adjusted their daily activities and exercise routines, potentially impacting the burden of foot and ankle disease. The purpose of the present study was to compare diagnoses made in an orthopaedic foot and ankle clinic during the months of the COVID-19 pandemic to diagnoses made during the same months of the previous year. Methods: A retrospective review of new patients presenting to our group of four fellowship-trained orthopaedic foot and ankle surgeons was performed. Patients in the COVID-19 group presented between March 22, 2020 (the beginning of our shelter-in- place ordinance) and July 1, 2020. Patients in the control group presented during the same period of the previous year. Final diagnosis was characterized. Chronicity was classified as acute (symptom duration <= 1 month) or chronic (symptom duration > 1 month). Diagnoses were classified as fractures (e.g. ankle fractures, foot fractures) or activity-related (e.g. plantar fasciitis, ankle sprain). Pearson Chi-squared tests were performed to assess for differences in patient presentations between the COVID-19 and control periods. Results: A total of 1,409 new patient visits were reviewed with 449 visits in the COVID-19 group and 960 visits in the control group. The COVID-19 group had a significantly higher proportion of ankle fractures (8.7% versus 5.4%; p=0.020) and stress fractures (4.2% versus 2.2%, p=0.031), but a smaller proportion of Achilles tendon ruptures (0.7% versus 2.5%; p=0.019). Similarly, the COVID-19 group had a higher proportion of acute injuries (35.4% versus 23.5%; p<0.001). No difference was seen between diagnoses classified as fractures or those classified as activity-related. Finally, the COVID-19 group had a higher proportion of acute activity-related injuries (16.0% versus 11.7%; p=0.023) and acute fractures (14.0% versus 8.4%; p=0.001), but a lower proportion of chronic activity-related injuries (22.5% versus 28.1%; p=0.025). Conclusion: The COVID-19 pandemic caused a marked shift in the pathology presenting to the orthopaedic foot and ankle clinic. There was an increase in ankle fractures, stress fractures, and acute injuries when compared to the previous year, and a decrease in Achilles tendon ruptures and chronic injuries. This shift may reflect both the adoption of different activities during the quarantine period and a reluctance to present to a medical environment for evaluation of non-urgent injuries.
Extensor Tendon Transfers for Treatment of Foot Drop in Charcot-Marie-Tooth Disease: A Biomechanical Evaluation
Authors: Michalski Max , An Tonya W. , Metzger Melodie F. , Nelson Trevor , Pfeffer Glenn B. 
Published: March 2021

Category: Midfoot/Forefoot; Ankle; Lesser Toes; Other Introduction/Purpose: Transfer of the Extensor hallucis longus (EHL) and extensor digitorum longus (EDL) tendons is an underutilized procedure for the treatment of drop foot in patients with Charcot-Marie-Tooth disease (CMT). Transfer of these tendons should be considered for augmentation of ankle dorsiflexion in the CMT population, regardless of the presence of clawed toes. The preferred site for tendon transfer, however, remains unknown. We hypothesized that EHL/EDL transfers will improve ankle dorsiflexion compared to the intact state but will produce similar motion at either the metatarsal necks or cuneiforms. Methods: Eight fresh-frozen cadaveric specimens transected at the mid-tibia were mounted into a specialized jig with the ankle held in 20 degrees of plantarflexion. The EHL and EDL tendons were isolated and connected to linear actuators with suture. Diodes secured on the 1st metatarsal, 5th metatarsal and tibia provided optical data for tibiopedal position in 3-dimensions. After preloading, the tendons were tested at 25%, 50%, 75% and 100% of maximal physiologic force for the EHL and EDL muscles, individually and combined. Results: Transfers to metatarsal and cuneiform locations significantly improved ankle dorsiflexion compared to the intact state. No difference was observed between these transfer sites. Following transfer, only 25% of maximal force by combined EHL and EDL was required to achieve a neutral foot position. Conclusion: Transfer of the long toe extensors, into either the metatarsals or cuneiforms, significantly increases dorsiflexion of the ankle. Transfer should be considered for augmentation of dorsiflexion in the CMT population, regardless of the presence of clawed toes. This study supports tendon transfers into the cuneiforms, which involves less time, fewer steps and easier tendon balancing without compromising dorsiflexion power.
Accessibility of the Metatarsal Head Comparing Distraction and Plantarflexion in a 2-Portal Technique for First Metatarsophalangeal (MTP 1) Joint Arthroscopy
Authors: Willegger Madeleine , Czerny Katharina , Hirtler Lena 
Published: March 2021

Category: Arthroscopy; Midfoot/Forefoot Introduction/Purpose: Arthroscopic treatment of osteochondral lesion of the first metatarsophalangeal (MTP1) joint is an established procedure. Non-invasive distraction is most commonly applied when a dorsal 2-portal technique is used. Alternatively, plantarflexion can be utilized. In order to compare the arthroscopic reachability of the first metatarsal head, a laboratory study in anatomical specimens was performed. Methods: Twenty matched pairs (n=40) of fresh-frozen lower leg specimens were obtained and randomly assigned into two groups, a distraction (DIS) and a plantarflexion (PF) group, respectively. A standard 2-portal approach (dorsolateral and dorsomedial portals) with a 1.9mm 30° scope was used. The arthroscopic accessibility of the first metatarsal head was evaluated using chondral picks. Markings at the metatarsal heads were made intraoperatively and measured after exarticulation. Results: In the DIS group the mean accessible area was 58.03%, while the accessible area in the PF group was 55.93%. Though there is a small difference between the two groups, this difference was not statistically significant (p=0.51). Range of motion of the MTP 1 joint did not affect reachability. In one specimen (2.5%) the dorsomedial hallucal nerve was injured during arthroscopy. Conclusion: Access to the MTP1-joint for the treatment of osteochondral lesions is similar using distraction or plantarflexion during arthroscopy. The plantarflexion technique has the advantage of less surgical equipment needed. The dorsomedial hallucal nerve is at danger at the medial portal.
Characterization and statistical modeling of glycosylation changes in sickle cell disease
Authors: Ashwood Heather E. , Ashwood Christopher , Schmidt Anna P. , Gundry Rebekah L. , Hoffmeister Karin M. , Anani Waseem Q. 
Published: March 2021

AbstractSickle cell disease is an inherited genetic disorder that causes anemia, pain crises, organ infarction, and infections in 13 million people worldwide. Previous studies have revealed changes in sialic acid levels associated with red blood cell sickling and showed that stressed red blood cells bare surface-exposed clustered terminal mannose structures mediating hemolysis, but detailed glycan structures and anti-glycan antibodies in sickle cell disease remain understudied. Here, we compiled results obtained through lectin arrays, glycan arrays, and mass spectrometry to interrogate red blood cell glycoproteins and glycan-binding proteins found in the plasma of healthy individuals and patients with sickle cell disease and sickle cell trait. Lectin arrays and mass spectrometry revealed an increase in α2,6 sialylation and a decrease in α2,3 sialylation and blood group antigens displayed on red blood cells. Increased binding of proteins to immunogenic asialo and sialyl core 1, Lewis A, and Lewis Y structures was observed in plasma from patients with sickle cell disease, suggesting a heightened anti-glycan immune response. Data modeling affirmed glycan expression and plasma protein binding changes in sickle cell disease but additionally revealed further changes in ABO blood group expression. Our data provide detailed insights into glycan changes associated with sickle cell disease and refer glycans as potential therapeutic targets.
Nicotine upregulates ACE2 expression and increases competence for SARS-CoV-2 in human pneumocytes
Authors: Maggi Fabrizio , Rosellini Alfredo , Spezia Pietro Giorgio , Focosi Daniele , Macera Lisa , Lai Michele , Pistello Mauro , de Iure Antonio , Tomino Carlo , Bonassi Stefano , Russo Patrizia 
Published: March 2021

The coronavirus disease 2019 (COVID-19) pandemic has a variable degree of severity according to underlying comorbidities and life-style. Several research groups have reported an association between cigarette smoking and increased severity of COVID-19. The exact mechanism of action is largely unclear.We exposed low angiotensin-converting enzyme 2 (ACE2)-expressing human pulmonary adenocarcinoma A549 epithelial cells to nicotine and assessed ACE2 expression at different times. We further used the nicotine-exposed cells in a virus neutralisation assay.Nicotine exposure induces rapid and long-lasting increases in gene and protein expression of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) receptor ACE2, which in turn translates into increased competence for SARS-CoV-2 replication and cytopathic effect.These findings show that nicotine worsens SARS-CoV-2 pulmonary infection and have implications for public health policies.
Spatiotemporal heterogeneity and its determinants of COVID-19 transmission in typical labor export provinces of China
Authors: Wang Li , Xu Chengdong , Wang Jinfeng , Qiao Jiajun , Yan Mingtao , Zhu Qiankun 
Published: March 2021

Abstract
Background
Previous studies have indicated that the risk of infectious disease spread is greatest in locations where a population has massive and convenient access to the epicenter of an outbreak. However, the spatiotemporal variations and risk determinants of COVID-19 in typical labor export regions of China remain unclear. Understanding the geographical distribution of the disease and the socio-economic factors affecting its transmission is critical for disease prevention and control.

Methods
A total of 2152 COVID-19 cases were reported from January 21 to February 24, 2020 across the 34 cities in Henan and Anhui. A Bayesian spatiotemporal hierarchy model was used to detect the spatiotemporal variations of the risk posed by COVID-19, and the GeoDetector q statistic was used to evaluate the determinant power of the potential influence factors.

Results
The risk posed by COVID-19 showed geographical spatiotemporal heterogeneity. Temporally, there was an outbreak period and control period. Spatially, there were high-risk regions and low-risk regions. The high-risk regions were mainly in the southwest areas adjacent to Hubei and cities that served as economic and traffic hubs, while the low-risk regions were mainly in western Henan and eastern Anhui, far away from the epicenter. The accessibility, local economic conditions, and medical infrastructure of Wuhan in Hubei province all played an important role in the spatiotemporal heterogeneity of COVID-19 transmission. The results indicated that the q statistics of the per capita GDP and the proportion of primary industry GDP were 0.47 and 0.47, respectively. The q statistic of the population flow from Wuhan was 0.33. In particular, the results showed that the q statistics for the interaction effects between population density and urbanization, population flow from Wuhan, per capita GDP, and the number of doctors were all greater than 0.8.

Conclusions
COVID-19 showed significant spatiotemporal heterogeneity in the labor export regions of China. The high-risk regions were mainly located in areas adjacent to the epicenter as well as in big cities that served as traffic hubs. Population access to the epicenter, as well as local economic and medical conditions, played an important role in the interactive effects of the disease transmission.
Value of gadoxetic acid-enhanced MRI for microvascular invasion of small hepatocellular carcinoma: a retrospective study
Authors: Zhou Meng , Shan Dan , Zhang Chunhui , Nie Jianhua , Wang Guangyu , Zhang Yanqiao , Zhou Yang , Zheng Tongsen 
Published: March 2021

Abstract
Background
The objective of this study was to analyze the accuracy of gadolinium–ethoxybenzyl–diethylenetriamine penta–acetic acid enhanced magnetic resonance imaging (Gd–EOB–DTPA–MRI) for predicting microvascular invasion (MVI) in patients with small hepatocellular carcinoma (sHCC) preoperatively.

Methods
A total of 60 sHCC patients performed with preoperative Gd–EOB–DTPA–MRI in the Harbin Medical University Cancer Hospital from October 2018 to October 2019 were involved in the study. Univariate and multivariate analyses were performed by chi–square test and logistic regression analysis. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of Gd–EOB–DTPA–MRI were performed by receiver operating characteristic (ROC) curves.

Results
Univariate analysis indicated that alanine aminotransferase (≥ 39.00U/L), poorly differentiated pathology, and imaging features including grim enhancement, capsule enhancement, arterial halo sign and hepatobiliary features (tumor highly uptake, halo sign, spicule sign and brush sign) were associated with the occurrence of MVI (p < 0.05). Multivariate analysis revealed that rim enhancement and hepatobiliary spicule sign were independent predictors of MVI (p < 0.05). The area under the ROC curve was 0.917 (95% confidence interval 0.838–0.996), and the sensitivity was 94.74%.

Conclusions
The morphologies of hepatobiliary phase imaging, especially the spicule sign, showed high accuracy in diagnosing MVI of sHCC. Rim enhancement played a significant role in diagnosing MVI of sHCC.
Age-specific definition of low anti-Mullerian hormone and associated pregnancy outcome in women undergoing IVF treatment
Authors: Zhao Depeng , Fan Jing , Wang Ping , Jiang Xuan , Yao Jilong , Li Xuemei 
Published: March 2021

Abstract
Background
The age-specific definition of low anti-müllerian hormone (AMH) is lacking. This study aims to define an age-specific reference for low AMH and to evaluate the associated outcome in women undergoing IVF treatment.

Methods
A retrospective study was performed in women receiving IVF treatment at the Shenzhen maternity and child healthcare hospital between September 2016 and September 2018. We excluded cases without AMH concentration. Polynomial least-squares regression was used to estimate the age-specific reference ranges for AMH after log-transformed. The age-specific 10th centile was defined as the threshold of low AMH concentration.

Results
A total of 909 patients were analyzed in this study. The age-specific reference ranges for AMH were established using linear regression model and resulted in an age-specific equation for mean: mean of LnAMH = (− 0.085 × age) + 3.722 (ng/ml, in unit). Women with AMH level higher than 10th centile had favorable outcomes in ovarian stimulation compared to those with low AMH level. In patients younger than 35 years, the rates of clinical pregnancy per transfer and ongoing pregnancy per transfer in the subgroup with AMH level higher than 10th centile were significantly higher than that in the subgroup of low AMH level, 57% versus 31.3% p = 0.003 and 51.9% versus 21.9% p = 0.001, respectively.

Conclusion
Women with AMH lower than age-specific 10th centile had significantly unfavorable outcomes after IVF treatment. The age-specific 10th centile of AMH concentration may be useful to predict the outcome of IVF treatment.
Evaluation of percutaneous transcatheter embolization for pulmonary arteriovenous malformations
Authors: Wu ZhengZhong , Lin JunQing , Yang WeiZhu , Jiang Na , Huang Ning , Clavijo Leonardo C. 
Published: March 2021

Abstract
Background
The purpose of this study was to assess the safety and efficacy of percutaneous transcatheter embolization (TCE) for the treatment of pulmonary arteriovenous malformations (PAVMs).

Methods
Forty-three consecutive patients (n = 17 males; n = 26 females) with 72 untreated PAVMs underwent coil and/or plug embolization between January 2010 and February 2018. The mean patient age was 42 ± 14 years (range 19–71 years). The median size of the feeding artery was 7.9 ± 2.9 mm (range 3.5–14.0 mm). The arterial blood gas level and cardiac function of all patients were analysed. The technical success rate, recanalization rate, and complications were evaluated. Computed tomography angiography (CTA) examinations were scheduled for 12 months after treatment and every 2–4 years thereafter.

Results
Twenty-five PAVMs were treated with coils alone, twenty-one were treated with plugs alone, and twenty-six were treated with both coils and plugs. The technical success rate was 100%. There were no complications during operation. However, one patient (2.3%) had pulmonary thrombosis and embolism post-operation. The patients’ pre-operative and post-operative PaO2 and SaO2 levels were significantly different (p < 0.01). A comparison of the New York Heart Association (NYHA) grade before and after embolization in all patients showed a significant decrease in the post-operative grade (p < 0.01). The 72 PAVMs were divided into three groups (coils only group [n = 25], plugs only group [n = 21], and coils/plugs combined group [n = 26]). After 12 months of follow-up, there were seven reperfusion PAVMs in the coil group, seven reperfusion PAVMs in the plug group, and 1 reperfusion PAVM in the combined group. There were significant differences between the two groups and the combined group.

Conclusion
Percutaneous TCE is safe and effective for the treatment of PAVMs. A combination of coils and vascular plugs may be useful for preventing recanalization after the embolization of PAVMs.
Hyperthermia in a pediatric patient with neuroblastoma during anesthesia: a case report
Authors: Wang Chuan , Xin Wenqiong , Ji Yi 
Published: March 2021

Abstract
Background
Neuroblastoma is the most common malignant extracranial solid tumor in pediatrics patients. Intraoperative hyperthermia is extremely rare in patients with neuroblastoma and can cause a series of complications. Here, we represent a case of neuroblastoma accompanied by hyperthermia during anesthesia, and propose a rational explanation and management options.

Case presentation
The patient had gait disturbance and sitting-related pain without fever. Magnetic resonance imaging revealed a soft tissue mass located in the right posterior mediastinum, paravertebral space and canalis vertebralis. Serum tumor marker screening showed that the patient had increased epinephrine, norepinephrine and neuron specific enolase levels, with an increased 24 hour urine vanillylmandelic acid level. Intraspinal tumor resection was conducted. The temperature of the patient rapidly arose to 40.1 °C over 10 minutes when waiting for tracheal extubation. The arterial gas analysis results indicated malignant hyperthermia was less likely, and dantrolene was not administered. Physical cooling methods were used, and the temperature dropped to 38.6 ℃. The trachea was successfully extubated. Histological results confirmed the diagnosis of neuroblastoma.

Conclusions
Hyperthermia during anesthesia is a serious adverse event. Catecholamines secreted from neuroblatoma cells can lead to hypermetabolism and hyperthermia. Surgeons and anesthesiologists should be aware of the possibility of hyperthermia in patients with neuroblastoma.
Excess mortality for care home residents during the first 23 weeks of the COVID-19 pandemic in England: a national cohort study
Authors: Morciano Marcello , Stokes Jonathan , Kontopantelis Evangelos , Hall Ian , Turner Alex J. 
Published: March 2021

Abstract
Background
To estimate excess mortality for care home residents during the COVID-19 pandemic in England, exploring associations with care home characteristics.

Methods
Daily number of deaths in all residential and nursing homes in England notified to the Care Quality Commission (CQC) from 1 January 2017 to 7 August 2020. Care home-level data linked with CQC care home register to identify home characteristics: client type (over 65s/children and adults), ownership status (for-profit/not-for-profit; branded/independent) and size (small/medium/large). Excess deaths computed as the difference between observed and predicted deaths using local authority fixed-effect Poisson regressions on pre-pandemic data. Fixed-effect logistic regressions were used to model odds of experiencing COVID-19 suspected/confirmed deaths.

Results
Up to 7 August 2020, there were 29,542 (95% CI 25,176 to 33,908) excess deaths in all care homes. Excess deaths represented 6.5% (95% CI 5.5 to 7.4%) of all care home beds, higher in nursing (8.4%) than residential (4.6%) homes. 64.7% (95% CI 56.4 to 76.0%) of the excess deaths were confirmed/suspected COVID-19. Almost all excess deaths were recorded in the quarter (27.4%) of homes with any COVID-19 fatalities. The odds of experiencing COVID-19 attributable deaths were higher in homes providing nursing services (OR 1.8, 95% CI 1.6 to 2.0), to older people and/or with dementia (OR 5.5, 95% CI 4.4 to 6.8), amongst larger (vs. small) homes (OR 13.3, 95% CI 11.5 to 15.4) and belonging to a large provider/brand (OR 1.2, 95% CI 1.1 to 1.3). There was no significant association with for-profit status of providers.

Conclusions
To limit excess mortality, policy should be targeted at care homes to minimise the risk of ingress of disease and limit subsequent transmission. Our findings provide specific characteristic targets for further research on mechanisms and policy priority.