bluuebunny/crossref_metadata_2025 huggingface dataset:
Transurethral seminal vesiculoscopy for intractable hematospermia: experience from 144 patients
Authors: Chen Wei-Kang , Yu Dong-Dong , Chen Zhi-Xia , Li Peng-Fei , Cai Jian , Liu Yu-Peng , Wu Zhi-Gang
Published: March 2021

Purpose

to describe the methodology of transurethral seminal vesiculoscopy and the anatomy of the area of the verumontanum, and to determine the safety of this procedure, especially in terms of postoperative complications.

Methods

This retrospective observational study enrolled 144 patients with intractable hematospermia from May 2011 and August 2019. A 4.5/6.5-Fr vesiculoscope was inserted into the seminal vesicle to deal with the positive findings. The solution of quinolones was used to rinse each seminal vesicle.

Results

In this study, Transurethral seminal vesiculoscopy was successfully performed in 139 patients (96.53%). Hematospermia was alleviated or disappeared in 116 (80.56%) patients by less than half a year after surgery. Common intraoperative manifestations were hemorrhage, stones, utricle polyps and cysts. The surgical approach in our study were categorized into four types, including 24 (16.7%), 73 (50.7%), 42 (29.2%), and 5 (3.5%) cases in Type A (natural opening of the ejaculatory duct), B (trans-duct fenestration), C (trans-utricle fenestration), and D (not founded), respectively. Sexual function change was recorded in 12 patients of 111 patients, all by the method of trans-utricle fenestration, including 8 (7.21%), 3 (2.70%), and 1 (0.90%) patients in shorter intravaginal ejaculatory latency time, worse erection hardness and loss of orgasm, respectively.

Conclusion

Transurethral seminal vesiculoscopy is an effective and safe procedure for the management of hematospermia. The anatomy of the distal seminal tract should be understood more deeply and Wu’method (uncover-curtain method) needs to be promoted to verify its universality and safety. Besides, the complications of the function dysfunction should be discussed in the future in multi-center clinical trials.
Cytotoxicity activities and chemical characteristics of exopolysaccharides and intracellular polysaccharides of Physarum polycephalum microplasmodia
Authors: Do Tuyen T. H. , Lai Tran N. B. , Stephenson Steven L. , Tran Hanh T. M.
Published: March 2021

Background

Microbial polysaccharides have been reported to possess remarkable bioactivities. Physarum polycephalum is a species of slime mold for which the microplasmodia are capable of rapid growth and can produce a significant amount of cell wall-less biomass. There has been a limited understanding of the polysaccharides produced by microplasmodia of slime molds, including P. polycephalum. Thus, the primary objectives of this research were first to chemically characterize the exopolysaccharides (EPS) and intracellular polysaccharides (IPS) of P. polycephalum microplasmodia and then to evaluate their cytotoxicity against several cancer cell lines.

Results

The yields of the crude EPS (4.43 ± 0.44 g/l) and partially purified (deproteinated) EPS (2.95 ± 0.85 g/l) were comparable (p > 0.05) with the respective crude IPS (3.46 ± 0.36 g/l) and partially purified IPS (2.45 ± 0.36 g/l). The average molecular weight of the EPS and IPS were 14,762 kDa and 1788 kDa. The major monomer of the EPS was galactose (80.22%), while that of the IPS was glucose (84.46%). Both crude and purified IPS samples showed significantly higher cytotoxicity toward Hela cells, especially the purified sample and none of the IPSs inhibited normal cells. Only 38.42 ± 2.84% Hela cells remained viable when treated with the partially purified IPS (1 mg/ml). However, although only 34.76 ± 6.58% MCF-7 cells were viable when exposed to the crude IPS, but the partially purified IPS displayed non-toxicity to MCF-7 cells. This suggested that the cytotoxicity toward MCF-7 would come from some component associated with the crude IPS sample (e.g. proteins, peptides or ion metals) and the purification process would have either completely removed or reduced amount of that component. Cell cycle analysis by flow cytometry suggested that the mechanism of the toxicity of the crude IPS toward MCF-7 and the partially purified IPS toward Hela cells was due to apoptosis.

Conclusions

The EPS and IPS of P. polycephalum microplasmodia had different chemical properties including carbohydrate, protein and total sulfate group contents, monosaccharide composition and molecular weights, which led to different cytotoxicity activities. The crude and partially purified IPSs would be potential materials for further study relating to cancer treatment.
Global health on the front lines: an innovative medical student elective combining education and service during the COVID-19 pandemic
Authors: Altillo Brandon S. A. , Gray Megan , Avashia Swati B. , Norwood Aliza , Nelson Elizabeth A. , Johnston Clarissa , Bhavnani Darlene , Patel Hemali , Allen Coburn H. , Adeni Sarayu , Phelps Nicholas D. , Mercer Tim
Published: March 2021

Background

An innovative medical student elective combined student-directed, faculty-supported online learning with COVID-19 response field placements. This study evaluated students’ experience in the course, the curriculum content and format, and its short-term impact on students’ knowledge and attitudes around COVID-19.

Methods

Students responded to discussion board prompts throughout the course and submitted pre−/post-course reflections. Pre−/post-course questionnaires assessed pandemic knowledge and attitudes using 4-point Likert scales. Authors collected aggregate data on enrollment, discussion posts, field placements, and scholarly work resulting from course activities. After the elective, authors conducted a focus group with a convenience sample of 6 participants. Institutional elective evaluation data was included in analysis. Authors analyzed questionnaire data with summary statistics and paired t-tests comparing knowledge and attitudes before and after the elective. Reflection pieces, discussion posts, and focus group data were analyzed using content analysis with a phenomenological approach.

Results

Twenty-seven students enrolled. Each student posted an average of 2.4 original discussion posts and 3.1 responses. Mean knowledge score increased from 43.8 to 60.8% (p <  0.001) between pre- and post-course questionnaires. Knowledge self-assessment also increased (2.4 vs. 3.5 on Likert scale, p <  0.0001), and students reported increased engagement in the pandemic response (2.7 vs. 3.6, p <  0.0001). Students reported increased fluency in discussing the pandemic and increased appreciation for the field of public health. There was no difference in students’ level of anxiety about the pandemic after course participation (3.0 vs. 3.1, p = 0.53). Twelve students (44.4%) completed the institutional evaluation. All rated the course “very good” or “excellent.” Students favorably reviewed the field placements, suggested readings, self-directed research, and learning from peers. They suggested more clearly defined expectations and improved balance between volunteer and educational hours.

Conclusions

The elective was well-received by students, achieved stated objectives, and garnered public attention. Course leadership should monitor students’ time commitment closely in service-learning settings to ensure appropriate balance of service and education. Student engagement in a disaster response is insufficient to address anxiety related to the disaster; future course iterations should include a focus on self-care during times of crisis. This educational innovation could serve as a model for medical schools globally.
Biomechanical study of Tile C3 pelvic fracture fixation using an anterior internal system combined with sacroiliac screws
Authors: Liu Lin , Zeng Donggui , Fan Shicai , Peng Yongxing , Song Hui , Jin Dadi , Zeng Letian
Published: March 2021

Background

How to perform minimally-invasive surgery on Tile C pelvic fractures is very difficult, and it is also a hot topic in orthopedic trauma research. We applied minimally-invasive treatment using an anterior internal fixator combined with sacroiliac screws.

Objectives

To compare the biomechanical properties of different fixation models in pelvic facture specimens, using an internal fixation system or a steel plate combined with sacroiliac screws.

Methods

Sixteen fresh adult cadaver pelvic specimens were randomly separated into four groups named A, B, C, and D. The four groups were respectively stabilized using a two-screwed, three-screwed, or four-screwed anterior internal fixator or a steel plate with sacroiliac screws. All models were tested in both standing and sitting positions. Vertical loads of 600 N were applied increasingly. Shifts of bilateral sacroiliac joints and pubis rupture were measured.

Results

The shifts in sacroiliac joints and pubis rupture in the standing position were all less than 3.5 mm, and the shifts in the sitting position were all less than 1 mm. In the standing position, the results of shifts in the sacroiliac joints were group C < group D < group B < group A. For comparisons between A:B and C:D, P > 0.05. For comparisons between A, B:C, and D, P < 0.05. The results of shifts in pubis ruptures were group D < group C < group B < group A. In the comparison between C:D, P > 0.05; for comparisons between A:B, A:C, A:D, B:C, and B:D, P < 0.05. In the sitting posture, the results of shifts in the sacroiliac joints were group C < group D < group B < group A, and the shifts in the pubis ruptures were group D < group C < roup B < group A. For comparison between C:D, P > 0.05. For comparisons between A:B, A:C, A:D, B:C, and B:D, P < 0.05.

Conclusion

Use of an anterior internal fixator combined with sacroiliac screws effectively stabilized Tile C3 pelvic fractures. The stability of specimens increased as the number of screws in the internal fixator increased.
OPG/RANKL/RANK gene methylation among alcohol-induced femoral head necrosis in northern Chinese men
Authors: Wang Tiantian , Wang Fei , Liu Tingting , Sun Menghu , An Feimeng , Liu Chang , Tian Ye , Cao Yuju , Wang Jianzhong
Published: March 2021

Background and purpose

Alcohol-induced osteonecrosis of the femoral head (ONFH) is a complex and heterogeneous disease. Genetic factors and epigenetic modifications are one of the pathogenesis of the disease. However, the influence of epigenetic factors on the disease has not been systematically studied. Our research aims to determine the methylation changes of alcohol-induced ONFH.

Methods

An analytical cross-sectional study of a Chinese male population (50 alcohol-induced ONFH patients and 50 controls). The EpiTYPER of the Sequenom MassARRAY platform was used to detect the DNA methylation status of 132 cytosine-phosphate-guanine (CpG) sites in the OPG/RANKL/RANK gene promoter region.

Results

In the whole study group, the chi-square test was used to analyze the methylation rate between the two groups, and six CpG sites were found to be different, among which OPG1_CpG_2, OPG3_CpG_4, RANK1_CpG_6, RANK3_CpG_10, RANKL2_CpG_21, and RANKL2_CpG_46 in the case group were higher than those in the control group, while OPG4_CpG_2 was lower than that in the control group. The results showed that in patients with alcohol-induced ONFH, 146 CpG sites were examined for differences in methylation levels compared with healthy controls, 32 of which were not detected, and 23 of the remaining 114 sites showed differences in methylation levels compared with alcohol-induced ONFH patients. Receiver operator characteristic (ROC) curve analysis demonstrated the methylation levels of OPG/RANKL/RANK could efficiently predict the existence of alcohol-induced ONFH.

Conclusion

Our study of Chinese men suggests that several CpG sites in the OPG/RANKL/RANK gene in peripheral blood leukocytes of patients with alcohol-induced ONFH are in an abnormal methylation state (hypermethylation tended to be more frequent).
Traumatic spinal cord injury caused by low falls and high falls: a comparative study
Authors: Zhang Zhen-Rong , Wu Yao , Wang Fang-Yong , Wang Wen-Jing
Published: March 2021

Background

Quite a few traumatic spinal cord injuries (TSCI) were caused by falls. However, the comparison of different causes of TSCI or the epidemiological characteristics of TSCI caused by falls of different heights are rare. This study investigated the epidemiological characteristics of TSCI caused by falls and conducted a comparison between low falls and high falls.

Method

Data from cases with TSCI admitted to China Rehabilitation Research Center from 2010 to 2019 were collected, including age, gender, occupation, cause, neurological level, and severity of the injury in admission, combined injuries, complications, and rehabilitation length of stay. Mann-Whitney U and chi-square (χ2) tests were used to assess the differences between two groups at a statistical significance level of 0.05.

Result

A total of 1858 TSCI cases were included and 41.7% were caused by falls, 11.4% by low falls and 30.3% by high falls, respectively. Patients with fall-induced TSCI were older and had a shorter rehabilitation length of stay than those with non-fall-induced TSCI. Patients with high fall-induced TSCI were younger and more likely to suffer from paraplegia, severer injuries, and combined injuries, and had longer time from injury to rehabilitation and rehabilitation length of stay, compared with patients with low fall-induced TSCI.

Conclusion

Falls is the leading causes of TSCI and high fall is becoming more common. Attention not only should be paid to high falls for the severe injury and longer hospitalization, but also low falls due to the higher neurological level of the injury and the aging of population in China.
The gut microbial composition in polycystic ovary syndrome with insulin resistance: findings from a normal‐weight population
Authors: He Fangfang , Li Yumei
Published: March 2021

Background

Limited studies have reported the relationship between intestinal flora dysbiosis and clinical characteristics in polycystic ovary syndrome (PCOS). However, the structure and characteristics of gut microbiota in PCOS have not been fully elucidated.

Objective

To analyze the composition of the Intestinal flora population in normal-weight women with PCOS and insulin resistance(IR) compared to PCOS alone and healthy women.

Methods

A total of 14 PCOS patients with insulin resistant(PCOS-IR) and 12 PCOS alone (PCOS-NIR), and 10 age- and body mass index-matched healthy control women (HC). BMI: 18.5–23.9 kg/m2. The bacterial 16 S rDNA V3-V4 fragment was amplified and sequenced. Then, the sequencing data were analyzed for species annotation, community diversity, and inter-group differences, to explore gut microbial characteristics of the subjects and their correlation with clinical parameters.

Results

No significant difference in diversity was observed between PCOA and sample cluster analysis among the three groups (Beta-diversity) and Alpha-diversity. The relative abundance of Rothia, Ruminococcus, and Enterococcus was significantly higher in the PCOS-IR group than in the other two groups (P < 0.05), while that of Prevotella was dramatically decreased (P < 0.05). The abundance of Enterococcus was positively correlated with waist circumference, hip circumference, diastolic blood pressure, and insulin resistance index. Meanwhile, Rothia abundance is positively associated with waist circumference and free fatty acids.

Conclusions

The gut microbial composition of PCOS patients with insulin resistance is different from that of PCOS alone and healthy women. The difference is correlated with the clinical characteristics of PCOS, with regards to insulin resistance, abdominal obesity, free fatty acids, and other indicators. PCOS-IR patients have an increased abundance of Enterococcus which potentially the intestinal environment of the host by enriching the metabolic pathways related to insulin resistance, causing the occurrence and development of PCOS.
Urinary sodium-to-potassium ratio associates with hypertension and current disease activity in patients with rheumatoid arthritis: a cross-sectional study
Authors: Minamino Hiroto , Katsushima Masao , Hashimoto Motomu , Fujita Yoshihito , Yoshida Tamami , Ikeda Kaori , Isomura Nozomi , Oguri Yasuo , Yamamoto Wataru , Watanabe Ryu , Murakami Kosaku , Murata Koichi , Nishitani Kohei , Tanaka Masao , Ito Hiromu , Ohmura Koichiro , Matsuda Shuichi , Inagaki Nobuya , Morinobu Akio
Published: March 2021

Background

Excessive salt intake is thought to exacerbate both development of hypertension and autoimmune diseases in animal models, but the clinical impact of excessive salt in rheumatoid arthritis (RA) patients is still unknown. We performed a cross-sectional study to clarify the associations between salt load index (urinary sodium-to-potassium ratio (Na/K ratio)), current disease activity, and hypertension in an RA population.

Methods

Three hundred thirty-six participants from our cohort database (KURAMA) were enrolled. We used the spot urine Na/K ratio as a simplified index of salt loading and used the 28-Joint RA Disease Activity Score (DAS28-ESR) as an indicator of current RA disease activity. Using these indicators, we evaluated statistical associations between urinary Na/K ratio, DAS28-ESR, and prevalence of hypertension.

Results

Urinary Na/K ratio was positively associated with measured systolic and diastolic blood pressure and also with prevalence of hypertension even after covariate adjustment (OR 1.34, p <  0.001). In addition, increased urinary Na/K ratio was significantly and positively correlated with DAS28-ESR in multiple regression analysis (estimate 0.12, p <  0.001), as was also the case in gender-separated and prednisolone-separated sub-analyses.

Conclusion

Urinary Na/K ratio was independently associated with current disease activity as well as with prevalence of hypertension in RA patients. Thus, dietary modifications such as salt restriction and potassium supplementation should be investigated as a potential candidate for attenuating both disease activity and hypertension in RA patients.
Plasma glial fibrillary acidic protein detects Alzheimer pathology and predicts future conversion to Alzheimer dementia in patients with mild cognitive impairment
Authors: Cicognola Claudia , Janelidze Shorena , Hertze Joakim , Zetterberg Henrik , Blennow Kaj , Mattsson-Carlgren Niklas , Hansson Oskar
Published: March 2021

Introduction

Plasma glial fibrillary acidic protein (GFAP) is a marker of astroglial activation and astrocytosis. We assessed the ability of plasma GFAP to detect Alzheimer’s disease (AD) pathology in the form of AD-related amyloid-β (Aβ) pathology and conversion to AD dementia in a mild cognitive impairment (MCI) cohort.

Method

One hundred sixty MCI patients were followed for 4.7 years (average). AD pathology was defined using cerebrospinal fluid (CSF) Aβ42/40 and Aβ42/total tau (T-tau). Plasma GFAP was measured at baseline and follow-up using Simoa technology.

Results

Baseline plasma GFAP could detect abnormal CSF Aβ42/40 and CSF Aβ42/T-tau with an AUC of 0.79 (95% CI 0.72–0.86) and 0.80 (95% CI 0.72–0.86), respectively. When also including APOE ε4 status as a predictor, the accuracy of the model to detect abnormal CSF Aβ42/40 status improved (AUC = 0.86, p = 0.02). Plasma GFAP predicted subsequent conversion to AD dementia with an AUC of 0.84 (95% CI 0.77–0.91), which was not significantly improved when adding APOE ε4 or age as predictors to the model. Longitudinal GFAP slopes for Aβ-positive and MCI who progressed to dementia (AD or other) were significantly steeper than those for Aβ-negative (p = 0.007) and stable MCI (p < 0.0001), respectively.

Conclusion

Plasma GFAP can detect AD pathology in patients with MCI and predict conversion to AD dementia.
Missed myocardial infarction in a vicenarian with malignant anomalous right coronary artery causing acute coronary syndrome: a case report
Authors: Ali Nafeesah , Baggan Kandace , Khan Shari S. , Maharaj Paramanand , Ali Ronan G.
Published: March 2021

Background

Traditional coronary artery disease risk factors are well established and help risk stratify most patients presenting with chest pain syndromes. Young patients (under age 30 years) without other risk factors are thought to be at very low risk of coronary artery disease and acute coronary syndromes.

Case presentation

We highlight the case of a 27-year-old Afro-Caribbean male who presented to hospital with chest pain and was discharged from the emergency room because he was thought to be low risk for ischemic heart disease. Laboratory investigations subsequently confirmed acute coronary syndrome. He was found to have an anomalous right coronary artery with a malignant origin running between the aorta and pulmonary artery eventually requiring surgical correction. Anomalous origins of the coronary arteries are rare causes of acute coronary syndromes, chest pain, and sudden cardiac death.

Conclusion

Our patient could have easily had an adverse outcome as his diagnosis was missed by the initial treating physician. It is important to consider anomalous coronary artery origin in the evaluation of young symptomatic patients who may be otherwise low risk and not have traditional risk factors for ischemic heart disease.
Endogenous mitochondrial double‐stranded RNA is not an activator of the type I interferon response in human pancreatic beta cells
Authors: Coomans de Brachène Alexandra , Castela Angela , Musuaya Anyïshai E. , Marselli Lorella , Marchetti Piero , Eizirik Decio L.
Published: March 2021

Background

Type 1 diabetes (T1D) is an autoimmune disease characterized by the progressive destruction of pancreatic beta cells. Interferon-α (IFNα), an antiviral cytokine, is expressed in the pancreatic islets in early T1D, which may be secondary to viral infections. However, not all patients harboring a type I IFN signature present signals of viral infection, suggesting that this response might be initiated by other “danger signals”. Accumulation of mitochondrial double-stranded RNA (mtdsRNA; a danger signal), secondary to silencing of members of the mitochondrial degradosome, PNPT1 and SUV3, has been described to activate the innate immune response.

Methods

To evaluate whether mtdsRNA represents a “danger signal” for pancreatic beta cells in the context of T1D, we silenced PNPT1 and/or SUV3 in slowly proliferating human insulin-secreting EndoC-βH1 cells and in non-proliferating primary human beta cells and evaluated dsRNA accumulation by immunofluorescence and the type I IFN response by western blotting and RT-qPCR.

Results

Only the simultaneous silencing of PNPT1/SUV3 induced dsRNA accumulation in EndoC-βH1 cells but not in dispersed human islets, and there was no induction of a type I IFN response. By contrast, silencing of these two genes individually was enough to induce dsRNA accumulation in fibroblasts present in the human islet preparations.

Conclusions

These data suggest that accumulation of endogenous mtdsRNA following degradosome knockdown depends on the proliferative capacity of the cells and is not a mediator of the type I IFN response in human pancreatic beta cells.
Diagnostic and prognostic value of serum soluble CD163 in cirrhotic patients with hepatitis C virus-related hepatocellular carcinoma before and after locoregional therapy
Authors: Sakr Marwa Ahmed , Mohamed Khaled Abdel Hamid , Hussein Ahmed Mohamed , Fouad Mohamed Hassan , Allam Ahmed Samir , Safwat Eslam
Published: March 2021

Background

Tumor-associated macrophages (TAMs), inflammatory cells in tumor microenvironment, are crucial for the tumor occurrence and progression which in turn increase the expression of soluble CD163 (sCD163). Nevertheless, not much has been established regarding sCD163 and its connection to HCC diagnosis and prognosis. This study was conducted to evaluate the diagnostic and prognostic role of sCD163 in patients with HCC on top of HCV-related liver cirrhosis. Forty adult patients with HCV-related liver cirrhosis and HCC (HCC group) were randomly selected and subjected to locoregional therapies, either transarterial chemoembolization (TACE) or radiofrequency ablation (RFA). Four patients were excluded because of portal vein invasion. Another group of 20 patients with liver cirrhosis only served as controls (LC group). Routine laboratory studies and abdominal ultrasound were done for all. Alpha-fetoprotein (AFP) and sCD163 were measured twice, at baseline and 1-month post-intervention, using a commercially available enzyme-linked immunosorbent assay kit.

Results

At baseline, sCD163 showed an insignificant higher value in HCC group (p > 0.05). The best cutoff value for sCD163 and AFP was 6.2 mg/L and 195 ng/mL, respectively. AFP had a larger area under the curve (0.88 vs. 0.767). An overall significant decline was seen in sCD163 after treatment (6.5±1.5 to 3.1±2.5 mg/L; p < 0.001), while AFP showed an insignificant decrease (p > 0.05). Also, sCD163 decreased significantly in the eradicated cases (6.1±1.4 mg/L before intervention vs. 2.3±1.4 mg/L after intervention, p < 0.01), while there was a significant increase in the recurrent cases (8.4±0.4 mg/L before intervention vs. 10.3±1.6 after intervention; p < 0.05). Moreover, sCD163 showed a significant difference in its pre-intervention and post-intervention values between recurrent and eradicated HCC cases (p < 0.01).

Conclusions

It is concluded that sCD163 has a minor role as a diagnostic marker for HCC, yet it could be used as a good prognostic marker in predicting the tumor response to locoregional therapies.
Damped wave-equation-based first-arrival traveltime tomography using the embedded boundary method
Authors: Park Yunhui , Pyun Sukjoon
Published: March 2021

First-arrival traveltime tomography (FATT) is used to delineate shallow velocity structures to identify static effects in oil exploration as well as to characterize the near surface for geotechnical purposes. Because FATT is generally used for land seismic data processing, it becomes necessary to consider irregular topography especially when performing wave-based tomography. However, the standard Cartesian finite-difference method cannot properly handle irregular topography. Hence, the embedded boundary method (EBM) is incorporated into the frequency-domain damped-wave equation to correctly describe irregular topography. The developed modeling algorithm is used to calculate first-arrival traveltimes and to perform FATT. The EBM-based modeling algorithm accurately describes the irregular surfaces of numerical velocity models on a regular mesh by exploiting the mirror image principle. The accuracy of the EBM-based traveltime calculation is validated by using two homogeneous velocity models with dipping and complex surfaces. The validation results demonstrate that our algorithm is unaffected by the staircase approximation. FATT is then applied to synthetic and real data to demonstrate the applicability of the developed algorithm to velocity models with complex topography. For the real data example, the inverted velocity model is used to apply static corrections. The processing results demonstrate an improvement in the continuity of seismic events, thus confirming the accuracy of the developed FATT method.
Seismic wave modeling in vertically varying viscoelastic media with general anisotropy
Authors: Ouyang Fang , Zhao Jianguo , Dai Shikun , Wang Shangxu
Published: March 2021

Seismic anisotropy, wave attenuation, and dispersion are critical phenomena of wave propagation in real media. Full-wavefield modeling of wave behavior in such media plays an important role in investigating dynamic features of the earth’s interior and in full-waveform inversion of anisotropic parameters and velocity dispersion. We have developed a numerical scheme to model the full-waveform response from a point source in a vertically varying viscoelastic medium of arbitrary anisotropy. The method is implemented in the frequency domain, so the complexity of anelasticity and anisotropy can be described by a complex elastic stiffness matrix and frequency-dependent moduli can also be readily incorporated. In our scheme, we solve the elastodynamic equations for general anisotropy through finite-element method in the frequency-wavenumber domain and we use the stiffness reduction method to suppress reflections from artificial boundaries along the depth direction. A nonuniform 2D Fourier transform strategy is developed to reconstruct the spatial-domain counterparts from the wavenumber-domain solutions. The time-domain responses are then obtained by taking inverse fast Fourier transform with respect to frequency. We validate the method by comparing the numerical results with the exact solutions for a homogeneous transversely isotropic model and a two-layered model. In the application example, we further proved the feasibility and generality of the scheme using an attenuative, dispersive model with velocity and attenuation anisotropy. Our scheme enjoys significant advantages in incorporating various viscoelastic/dispersive behaviors and general anisotropy, and thus provides a useful tool for numerical simulation of dynamic responses in practical application.
Multiscale finite-difference method for frequency-domain acoustic wave modeling
Authors: Jiang Wei , Chen Xuehua , Jiang Shuaishuai , Zhang Jie
Published: March 2021

Conventional finite-difference frequency-domain (FDFD) methods can describe wave attenuation and velocity dispersion more easily than time-domain methods. However, there are significant challenges associated with the computational costs for solving the linear system when frequency-domain methods are applied in models with large dimensions or fine-scale property variations. Direct-iterative solvers and parallel strategies attempt a trade-off between memory and time costs. We have followed the general framework of a heterogeneous multiscale method and developed a multiscale FDFD approach to solve the Helmholtz equation with lower memory and time costs. To achieve this, the discrete linear system approximating the Helmholtz equation is constructed on a coarse mesh, making its dimension much smaller than that of conventional methods. The coefficient matrix in the linear system of dimension-reduction captures fine-scale heterogeneity in the media by coupling fine- and coarse-scale meshes. Several test models are used to verify the accuracy of our multiscale method and investigate potential sources of error. Numerical results demonstrate that our method accurately approximates the wavefields of fine-scale solutions at low frequencies of the source and could produce solutions with small errors by reducing the size of the coarse-mesh cells at high frequencies as well. Comparisons of computational costs with conventional FDFD methods show that our multiscale method significantly reduces computation time and memory consumption.
On cycle-skipping and misfit function modification for full-wave inversion: Comparison of five recent approaches
Authors: Pladys Arnaud , Brossier Romain , Li Yubing , Métivier Ludovic
Published: March 2021

Full-waveform inversion, a high-resolution seismic imaging method, is known to require sufficiently accurate initial models to converge toward meaningful estimations of the subsurface mechanical properties. This limitation is due to the nonconvexity of the least-squares distance with respect to the kinematic mismatch. We propose a comparison of five misfit functions promoted recently to mitigate this issue: adaptive waveform inversion, instantaneous envelope, normalized integration, and two methods based on optimal transport. We explain which principles these methods are based on and illustrate how they are designed to better handle kinematic mismatch than a least-squares misfit function. By doing so, we can exhibit specific limitations of these methods in canonical cases. We further assess the interest of these five approaches for application to field data based on a synthetic Marmousi case study. We illustrate how adaptive waveform inversion and the two methods based on optimal transport possess interesting properties, making them appealing strategies applicable to field data. Another outcome is the definition of generic tools to compare misfit functions for full-waveform inversion.
One Year of GH Treatment for Growth Failure in Children With Anorexia Nervosa: A Randomized Placebo-Controlled Trial
Authors: Léger Juliane , Fjellestad-Paulsen Anne , Bargiacchi Anne , Pages Justine , Chevenne Didier , Alison Marianne , Alberti Corinne , Guilmin-Crepon Sophie
Published: March 2021

Context

Children with anorexia nervosa (AN) are at risk of adult height deficit due to prolonged low height velocity (HV).

Objective

To investigate the effects of human growth hormone (GH) injections on HV in children with AN and severe growth impairment.

Design and participants

In this prospective, randomized, double-blind, single-center, proof-of-concept trial, children with AN and low HV (≤2 cm/year) for at least 18 months, and a bone age ≤12 years for girls and ≤14 years for boys, were randomized to receive daily subcutaneous injections of human GH (0.050 mg/kg/day) or placebo for 12 months.

Main outcome measures

Change in HV after 12 months.

Results

In total, 8 patients were assigned to the GH group and 6 to the placebo group. Patients had a median (25th-75th percentile) HV of 1.0 (0.5;1.5) cm/year. The effect of GH treatment increased strongly after 6 months, with a height gain after 12 months of 9.65 (8.0;11.6) cm for the GH group vs 3.85 (1.7;7.3) cm for the placebo group, with an absolute median (2.5th-97.5th percentile) difference between the groups of 5.8 (−1.85;9.68) cm after bootstrapping. The percentage of patients with a HV > 5 cm/year during the study period was higher in the GH group than in the placebo group (100% vs 50%, P = 0.05). Adverse events occurred in similar numbers in the 2 groups, were mild or nonfatal, and did not lead to treatment being stopped.

Conclusion

GH administration to improve HV is a potentially valid option for increasing HV in children with AN and prolonged severe growth failure.
Ovarian Reserve Biomarkers and Menstrual Cycle Length in a Prospective Cohort Study
Authors: Harris Benjamin S , Steiner Anne Z , Jukic Anne Marie
Published: March 2021

Context

While age-related changes in menstrual cycle length are well known, it is unclear whether anti-Müllerian (AMH) or other ovarian reserve biomarkers have a direct association with cycle length.

Objective

To determine the association between biomarkers of ovarian reserve and menstrual cycle length.

Methods

Secondary analysis using data from time to conceive (TTC), a prospective time to pregnancy cohort study. The age-independent association between cycle length and biomarkers of ovarian reserve was analyzed using linear mixed and marginal models. Study participants were TTC-enrolled women aged 30-44 years with no history of infertility who were attempting to conceive for <3 months were enrolled. Serum AMH, follicle-stimulating hormone, and inhibin B levels were measured on cycle day 2, 3, or 4. Participants recorded daily menstrual cycle data for ≤4 months. The primary outcome was menstrual cycle length; follicular and luteal phase lengths were secondary outcomes.

Results

Multivariable analysis included 1880 cycles from 632 women. Compared with AMH levels of 1.6 to 3.4 ng/mL, women with AMH <1.6 ng/mL had cycles and follicular phases that were 0.98 (95% CI –1.46, –0.50) and 1.58 days shorter (95% CI –2.53, –0.63), respectively, while women with AMH >8 ng/mL had cycles that were 2.15 days longer (95% CI 1.46, 2.83), follicular phases that were 2 days longer (95% CI 0.77, 3.24), and luteal phases that were 1.80 days longer (95% CI 0.71, 2.88).

Conclusion

Increasing AMH levels are associated with longer menstrual cycles due to both a lengthening of the follicular and the luteal phase independent of age.
Inserção dos Cuidados Paliativos na formação dos profissionais de educação física
Authors: Souza Filho Breno Augusto Bormann de , Tritany Érika Fernandes , Smethurst William Serrano , Gomes de Barros Mauro Virgilio
Published: March 2021

A recente Resolução nº 391 do Conselho Federal de Educação Física, de agosto de 2020, estimulou o debate acerca da ampliação do horizonte de atuação do Profissional de Educação Física (PEF) no Brasil, ao definir sua atuação em contextos hospitalares, em atividades relacionadas às áreas de atividades físicas e exercício físico, destinados a promoção, prevenção, proteção, educação, intervenção, recuperação, reabilitação, tratamento e Cuidados Paliativos. Nesse sentido, é importante que os PEF adquiram, ao longo de sua formação, conhecimentos e práticas relacionados aos Cuidados Paliativos (CP). Entretanto, são observadas lacunas na formação profissional e ausência de orientações na Diretriz Curricular Nacional sobre competências, habilidades e atitudes, no que tange a cuidados durante o percurso das doenças, cuidados de fim de vida, luto, e aspectos conceituais dos CP na formação básica do PEF. Assim, este artigo discute a importância da atuação do PEF nos CP, bem como a inclusão de conteúdos próprios à área dos CP em componentes curriculares da formação em Educação Física. Propõe-se, assim, ampliar e qualificar a atuação do PEF, e melhorar a qualidade da assistência prestada a pacientes, e seus familiares, em CP.
Variação sazonal das atividades físicas e sedentárias de estudantes no semiárido baiano
Authors: Jesus Gilmar Mercês de , Araujo Lara Daniele Matos dos Santos , Dias Lizziane Andrade , Barros Anna Karolina Cerqueira , Silva Juliana Silva e , Kupek Emil , Assis Maria Alice Altenburg de
Published: March 2021

Este estudo analisou a variação sazonal das atividades físicas e dos comportamentos sedentários de uma amostra por conveniência de crianças e adolescentes, de uma escola pública no semiárido baiano (n = 462; 52,9% de meninos; 7-12 anos). Trata-se de um estudo longitudinal de um ano de seguimento. Atividades físicas e comportamentos sedentários foram relatados no questionário Consumo Alimentar e Atividade Física de Escolares (Web-CAAFE). As medidas repetidas foram realizadas no outono, inverno e primavera. Os desfechos avaliados foram: quantidade de atividades físicas diária (AFD) e de comportamentos sedentários (CS), frequências de atividades físicas leves (AFL), moderadas (AFM) e vigorosas (AFV). Análises foram conduzidas via modelagem de equações de estimativa generalizada (GEE) (distribuição Poisson), com ajuste por temperatura ambiente e precipitação pluviométrica. Não houve variação sazonal estatisticamente significativa na AFD. No inverno, houve mais relatos de AFL (Coef² = 1,37; IC95%: 1,14-1,66) e de CS (Coef² = 1,16; IC95%: 1,05-1,29), enquanto AFV foram menos frequentes (Coef² = 0,83; IC95%: 0,71-0,97). AFV foram menos relatadas no outono (Coef² = 0,82; IC95%: 0,69-0,98). Sexo modificou o efeito das estações nas AFV, que entre meninos, ocorreram mais no outono (Coef² = 1,72 IC95%=1,16-2,56) e no inverno (Coef² = 1,84; IC95%: 1,26-2,69). Idade modificou efeito das estações sobre os CS. Durante o seguimento, houve mais CS na faixa etária 10-12 anos, porém, com diferença estatística significativa no outono e no início da primavera. O inverno favoreceu as AFL e os CS, mas restringiu as AFV, sobretudo entre meninas. Estudantes de 10-12 anos apresentaram mais CS, especialmente no outono e início da primavera.
Nursing through numerous deaths during COVID-19
Authors: Akpan Nsisongabasi
Published: March 2021

Nsisongabasi Akpan reflects on the challenges of moving from level 1 to level 3 patient care during the COVID-19 pandemic and the difficulties of staying motivated while facing frequent patient deaths.
Vertebral fractures and luxations in dogs and cats part 2: treatment and surgery options
Authors: Orgonikova Ivona , Brocal Josep , Bruto Cherubini Giunio , Palus Viktor
Published: March 2021

Assessing the presence of vertebral column instability is essential in animals with vertebral fractures or luxations. Spinal instability is most commonly assessed using a three-compartment model and unstable vertebral fractures and luxations require surgical stabilisation. In cases of compression of the spinal cord (by haematoma, traumatic intervertebral disc extrusion or bone fragment), decompression surgery is necessary. Prompt surgery prevents additional spinal cord damage, but the overall condition of the patient, including any concurrent injuries, needs to be continually kept in mind. The vertebral column can be stabilised using multiple techniques, such as screws, pins, polymethylmetacrylate and plating techniques, as well as external stabilisation and spinal stapling. Complications of spinal surgeries include haemorrhage, infection, neurological deterioration, particularly in cases of spinal stabilisations, implant loosening and failure.
Histopathology: how to get the best from gastrointestinal biopsies
Authors: Veiga-Parga Tamara , Palgrave Christopher J
Published: March 2021

Sampling of the gastrointestinal tract by endoscopic, or full thickness (open abdominal surgical) biopsy is an invaluable tool in the diagnosis and management of gastrointestinal disease in companion animals. This article gives recommendations on how to collect and submit endoscopic and full thickness biopsies of the gastrointestinal tract, in order to maximise their diagnostic value. It also covers interpretation of the histopathology report and examples of when further samplsing or additional testing may be advisable. It is important to note that these are general recommendations and it is prudent to contact the reporting laboratory with any specific queries or requests.
Latest clinical research
Authors: Greener Mark
Published: March 2021

Mark Greener summarises the latest studies relevant to primary care nurses
Advising patients on long-acting reversible contraception
Authors: Kochhar Suneeta
Published: March 2021

Suneeta Kochhar looks at what nurses can discuss with patients who require contraception
Managing foot care for people with diabetes
Authors: Robbie Jayne
Published: March 2021

Jayne Robbie explains the role practice nurses can play in identifying this time-sensitive condition
Sick day advice for people with diabetes
Authors: Stewart Martha
Published: March 2021

Martha Stewart discusses how illness affects diabetes management and outlines ‘sick-day advice’
Machine learning-based LIBS spectrum analysis of human blood plasma allows ovarian cancer diagnosis
Authors: Yue Zengqi , Sun Chen , Chen Fengye , Zhang Yuqing , Xu Weijie , Shabbir Sahar , Zou Long , Lu Weiguo , Wang Wei , Xie Zhenwei , Zhou Lanyun , Lu Yan , Yu Jin
Published: March 2021

Early-stage screening and diagnosis of ovarian cancer represent an urgent need in medicine. Usual ultrasound imaging and cancer antigen CA-125 test when prescribed to a suspicious population still require reconfirmations. Spectroscopic analyses of blood, at the molecular and atomic levels, provide useful supplementary tests when coupled with effective information extraction methods. Laser-induced breakdown spectroscopy (LIBS) was employed in this work to record the elemental fingerprint of human blood plasma. A machine learning data treatment process was developed combining feature selection and regression with a back-propagation neural network, resulting in classification models for cancer detection among 176 blood plasma samples collected from patients, including also ovarian cyst and normal cases. Cancer diagnosis sensitivity and specificity of respectively 71.4% and 86.5% were obtained for randomly selected validation samples.
Assessment of radiotherapy effect for nasopharyngeal cancer using plasma surface-enhanced Raman spectroscopy technology: errata
Authors: Wu Qiong , Qiu Sufang , Yu Yun , Chen Weiwei , Lin Huijing , Lin Duo , Feng Shangyuan , Chen Rong
Published: March 2021

Correction for ‘Assessment of radiotherapy effect for nasopharyngeal cancer using plasma surface-enhanced Raman spectroscopy technology’ by Qiong Wu et al. in [Biomed. Opt. Express 9, 3413 (2018)10.1364/BOE.9.003413].
Axial intensity distribution of a micro-Fresnel zone plate at an arbitrary numerical aperture
Authors: Liu Qiang , Liu Tao , Yang Shuming , Li Guoqing , Li Shaobo , He Tao
Published: March 2021

The axial focus number (the number of focal spots along the axial direction) and focus intensity of a micro-Fresnel zone plate (FZP) are analyzed from deep ultraviolet to infrared using the Fourier decomposition, the vectorial angular spectrum (VAS) theory, and the three-dimensional finite-difference time-domain (FDTD) method. For a low-numerical aperture (NA) micro-FZP (NA<0.1), there are multiple axial high-order foci, and the intensity of each focus decreases slowly. However, the intensity of each high-order focus decreases rapidly with NA increasing. For a relatively high-NA micro-FZP (NA>0.3), the axial high-order foci are suppressed and there is one single focus. A fast, precise, and cost-efficient additive manufacturing method, i.e. two-photon polymerization, is used to fabricate high-NA phase-type micro-FZPs. The experiment has validated the phenomenon of linear negative focal shift of a high-NA micro-FZP. This property can be particularly applied in precise measurement of micro-displacement, film thickness, micro/nano step height, and wavelength.
Stray light separation based on the changeable veiling glare index for the vacuum radiance temperature standard facility
Authors: Zhou Jingjing , Hao Xiaopeng , Song Jian , Xie Chenyu , Liu Yang , Wang Xia
Published: March 2021

The vacuum radiance temperature standard facility (VRTSF) is used to determine the temperature traceability of calibration blackbodies accurately for infrared remote sensing. However, the internal surfaces of the VRTSF can emit thermal radiation, which introduces stray light and reduces measurement accuracy. Previously, background subtraction was used to eliminate stray light, without considering dynamic changes in the environment. Therefore, we propose a changeable veiling glare index (CVGI) to evaluate stray light performance based on the concept of the veiling glare index. We analyze the radiation model of the VRTSF system and simulate the attribution of stray light. CVGI can be improved considerably by cooling and by using suitable stop sizes. Experiments performed in the VRTSF show that the CVGI is suitable for analyzing stray light. Using the CVGI, we simulate a method that can significantly reduce stray light in the VRTSF.
Cost-effective digital coherent short-reach transmission system with D8QAM and low-complexity DSP
Authors: Zhang Tingting , Xiang Qian , Zhang Sen , Liu Lei , Sygletos Stylianos , Zuo Tianjian
Published: March 2021

We propose a cost-effective digital coherent scheme with low-complexity digital signal processing (DSP) for short-reach optical interconnection. Differential 8-ary quadrature amplitude modulation (D8QAM) with 1-decision-aided adaptive differential decoding bypasses carrier recovery and enables cycle-slip-free operation. We experimentally demonstrate that the receiver sensitivity of 400-Gb/s D8QAM is insensitive to the laser type, and is the same as 400-Gb/s 16QAM in the case of 2-km transmission with a distributed feedback (DFB) laser. The proposed adaptive equalizer (AEQ) using real-valued finite impulse response (FIR) filters and shorter tap lengths for the real-imaginary filters allows hardware-efficient implementation with high robustness to the receiver-side timing skew. In the case of 400-Gb/s D8QAM 10-km transmission, our AEQ achieves comparable performance as conventional 4×4 real-valued multi-input multi-output (MIMO) and the existing simplified AEQs with complexity reduction of 50% and 14% respectively.