bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of mechanically compliant 3D composite scaffolds for bone tissue engineering applications
Authors: Anandan Dhivyaa , Mary Stella S. , Arunai Nambiraj N. , Vijayalakshmi U. , Jaiswal Amit Kumar
Published: October 2018

Cancellous bone region of the human native bone has the potential to bear significant mechanical loads. However, due to the following parameters such as low trabecular volume, more porosity, less thickness and more interconnectivity, cancellous bone is accessible to damage in accidents or when aging. This research led to the effective fabrication and engineering of cancellous region of the bone for its application in reconstruction or filling of bone voids after resection of large tumor mass. Scaffolds containing hydroxyapatite (HAp), polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP) (5% polymer and HAp concentrations) at different HAp: polymer composite ratios (50:50, 70:30 and 80:20), were fabricated by freeze–drying method using only water as solvent and ribose as crosslinker for the scaffolds. The fabricated scaffolds were characterized for its mechanical (compressive) strength, chemical properties using FT‐IR and XRD analyses, swelling and degradation studies, confirmation of mineralization process by immersion in simulated body fluid (SBF) for 7, 15 and 30 days, morphological analysis using scanning electron microscopy (SEM), and biocompatibility properties by performing MTT analysis. From the combined interpretation of the above mentioned tests, it was proven that 80:20 ratio of HAp to polymers was found to be the most suitable scaffold in terms of its optimal properties for its use as bone graft material for trabecular bone. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 3267–3274, 2018.
Telomere length analysis in residents of a community exposed to arsenic
Authors: Jimenez Villarreal Joel , Murillo Ortiz Blanca , Martinez Garza Sandra , Rivas Armendáriz Diana Isabel , Boone Villa Víctor Daniel , Carranza Rosales Pilar , Betancourt Martínez Nadia Denys , Delgado Aguirre Héctor , Morán Martínez Javier
Published: October 2018

Differentiated cells telomere length is an indicator of senescence or lifespan; however, in peripheral blood leukocytes the relative shortening of the telomere has been considered as a biological marker of aging, and lengthening telomere as an associated risk to cancer. Individual’s age, type of tissue, lifestyle, and environmental factors make telomere length variable. The presence of environmental carcinogens such as arsenic (As) influence as causal agents of these alterations, the main modes of action for As described are oxidative stress, reduction in DNA repair capacity, overexpression of genes, alteration of telomerase activity, and damage to telomeres. The telomeres of leukocytes resulting a finite capacity of replication due to the low or no activity of the telomerase enzyme, therefore, elongation telomere in this kind of cells is a potential biological marker associated with the development of chronic diseases and carcinogenesis.
Adriamycin inhibits embryonic development in zebrafish through downregulation of Kruppel‐like factor4
Authors: Akthar I. Syeda Thabassum , Pichiah P.B. Tirupathi , Arunachalam Sankarganesh , Raja Sudhakaran
Published: October 2018

Adriamycin is an effective anticancer drug used in a wide range of cancers. Anticancer drugs modulate oncogenes and nodal regulatory molecules that affect cell differentiation and organismal development. In this study, we explore the effect of adriamycin on Kruppel‐like factor4 (Klf4), an essential pluripotent factor by choosing zebrafish embryos as a model system. Klf4 is involved in the regulation of cellular growth, proliferation, and differentiation. In zebrafish embryogenesis, Klf4 is a major regulator of differentiation of polster in the anterior mesendoderm region of cells into hatching gland cells. The importance of this study is to check the effect of adriamycin on embryonic development. We found, adriamycin dose dependently altered the gene expression level of Klf4 that occurs in parallel to its detrimental effect on hatching. Supportively, cathepsin L and cyclase‐associated protein1 are the other two markers of hatching that are altered along with Klf4.
A bulk adjusted linear combination of atomic orbitals (BA‐LCAO) approach for nanoparticles
Authors: Kaledin Alexey L. , Hill Craig L. , Lian Tianquan , Musaev Djamaladdin G.
Published: October 2018

We describe a bulk adjusted linear combination of atomic orbitals (BA‐LCAO) approach for nanoparticles. In this method, we apply a many‐body scaling function (in similar manner as in the environment‐modified total energy based tight‐binding method) to the DFT‐derived diatomic AO interaction potentials (like in the conventional orbital‐based density‐functional tight binding approach) strictly according to atomic valences acquired naturally in a bulk structure. This modification, (a) facilitates all atom orbital‐based electronic structure calculations of charge carrier dynamics in nanoscale structures with a molecular acceptor, and (b) allows to closely match high‐level density functional calculation data (previously adjusted to the available experimental findings) for bulk structures. To advance practical application of the BA‐LCAO approach we parameterize the Hamiltonian of wurtzite CdSe by fitting its band structure to a high‐level DFT reference, corrected for experimentally measured band edges. Here, unlike in conventional DFTB approach, we: (1) use hydrogen‐like AOs for the basis as exact atomic eigenfunctions, while orbital energies of which are taken from experimentally measured ionization potentials, and (2) parameterize the many‐body scaling functions rather than the atomic wavefunctions. Development of this approach and parameters is guided by our goals to devise a method capable of simultaneously treating the problems of (i) interfacial electron/hole transfer between finite, variable size nanoparticles and electron scavenging molecules, and (ii) high‐energy electronic transitions (Auger transitions) that mediate multi‐exciton decay in quantum dots. Electronic structure results are described for CdSe quantum dots of various sizes. © 2018 Wiley Periodicals, Inc.
A multicomponent approach toward understanding emotion regulation in schizophrenia
Authors: Painter Janelle M. , Stellar Jennifer E. , Moran Erin K. , Kring Ann M.
Published: October 2018

Objectives

Emotion deficits are well documented in people with schizophrenia. Far less is known about their ability to implement emotion regulation strategies. We sought to explore whether people with schizophrenia can modify their emotion responses similar to controls.

Methods

People with (n = 25) and without (n = 21) schizophrenia were instructed to amplify positive‐emotion expression, reappraise negative emotion experience, and suppress physiological response. Multiple components of emotion response were measured (experience, expression, and physiology).

Results

Although people with schizophrenia showed increased positive expressivity following amplification and decreased negative emotion experience following reappraisal, overall, they expressed less positive emotion and experienced more negative emotion compared with controls. Neither group was effective at physiological suppression.

Conclusions

Together these findings suggest that people with schizophrenia can engage in amplification and reappraisal when explicitly instructed to do so, albeit additional practice may be necessary to modify emotion responses to levels similar to controls.
Muscle‐specific Perilipin2 down‐regulation affects lipid metabolism and induces myofiber hypertrophy
Authors: Conte Maria , Armani Andrea , Conte Giuseppe , Serra Andrea , Franceschi Claudio , Mele Marcello , Sandri Marco , Salvioli Stefano
Published: October 2018

Background

Perilipin2 (Plin2) belongs to a family of five highly conserved proteins, known for their role in lipid storage. Recent data indicate that Plin2 has an important function in cell metabolism and is involved in several human pathologies, including liver steatosis and Type II diabetes. An association between Plin2 and lower muscle mass and strength has been found in elderly and inactive people, but its function in skeletal muscle is still unclear. Here, we addressed the role of Plin2 in adult muscle by gain and loss of function experiments.

Methods

By mean of in vivo Plin2 down‐regulation (shPlin2) and overexpression (overPlin2) in murine tibialis anterior muscle, we analysed the effects of Plin2 genetic manipulations on myofiber size and lipid composition. An analysis of skeletal muscle lipid composition was also performed in vastus lateralis samples from young and old patients undergoing hip surgery.

Results

We found that Plin2 down‐regulation was sufficient to induce a 30% increase of myofiber cross‐sectional area, independently of mTOR pathway. Alterations of lipid content and modulation of genes involved in lipid synthesis occurred in hypertrophic muscles. In particular, we showed a decrease of triglycerides, ceramides, and phosphatidylcoline:phosphatidylethanolamine ratio, a condition known to impact negatively on muscle function. Plin2 overexpression did not change fibre size; however, lipid composition was strongly affected in a way that is similar to that observed in human samples from old patients.

Conclusions

Altogether these data indicate that Plin2 is a critical mediator for the control of muscle mass, likely, but maybe not exclusively, through its critical role in the regulation of intracellular lipid content and composition.
On the exact decomposition threshold for even cycles
Authors: Taylor Amelia
Published: October 2018

A graph has a ‐decomposition if its edge set can be partitioned into cycles of length . We show that if , then has a ‐decomposition, and if , then has a ‐decomposition, where and (we assume is large and satisfies necessary divisibility conditions). These minimum degree bounds are best possible and provide exact versions of asymptotic results obtained by Barber, Kühn, Lo and Osthus. In the process, we obtain asymptotic versions of these results when is bipartite or satisfies certain expansion properties.
Clinical characteristics and risk factors for stent–stone complex formation following biliary plastic stent placement in patients with common bile duct stones
Authors: Kaneko Junichi , Kawata Kazuhito , Watanabe Shinya , Chida Takeshi , Matsushita Masahiro , Suda Takafumi , Kobayashi Yoshimasa
Published: October 2018

Background

Stent–stone complex (SSC) formation is one of the complications of endoscopic biliary stent placement. This study aimed to clarify the clinical characteristics and risk factors for SSC formation following plastic stent (PS) placement in patients with common bile duct (CBD) stones.

Methods

We retrospectively reviewed the charts of 78 patients with CBD stones who had undergone 107 biliary stent placements as palliative treatment. Demographic, historical, and stent‐related data were collected and analyzed.

Results

At PS removal, SSC formations were observed in 18% of the 107 cases (SSC group) studied and not in the remaining 82% (non‐SSC group). The duration of PS placement was significantly longer in the SSC group. The increase in CBD diameter during the stenting period as well as the incidence of cholangitis at PS removal was significantly greater in the SSC group. Multivariate analysis identified long‐term (≥301 days) PS placement and the increase in CBD diameter during the stenting period as independent factors for SSC formation.

Conclusions

Long‐term PS placement induces a risk of SSC formation in patients with CBD stones. The increase in diameter of CBD during the period of PS placement is a predictive factor for SSC formation in this situation.
Learning curve and surgical factors influencing the surgical outcomes during the initial experience with laparoscopic pancreaticoduodenectomy
Authors: Nagakawa Yuichi , Nakamura Yoshiharu , Honda Goro , Gotoh Yoshitaka , Ohtsuka Takao , Ban Daisuke , Nakata Kohei , Sahara Yatsuka , Velasquez Vittoria Vanessa D. M. , Takaori Kyoichi , Misawa Takeyuki , Kuroki Tamotsu , Kawai Manabu , Morikawa Takanori , Yamaue Hiroki , Tanabe Minoru , Mou Yiping , Lee Woo‐Jung , Shrikhande Shailesh V. , Conrad Claudius , Han Ho‐Seong , Tang Chung Ngai , Palanivelu Chinnusamy , Kooby David A. , Asbun Horacio J. , Wakabayashi Go , Tsuchida Akihiko , Takada Tadahiro , Yamamoto Masakazu , Nakamura Masafumi
Published: October 2018

Background

Laparoscopic pancreaticoduodenectomy (LPD) requires sufficient laparoscopic training for optimal outcomes. Our aim is to determine the learning curve and investigate the factors influencing surgical outcomes during the learning curve.

Methods

We analyzed surgical results of 150 consecutive cases of LPD performed by three hepatopancreatobiliary surgeons during their 50 first cases. Learning curves were constructed by cumulative sum (CUSUM) analysis. Preoperative factors influencing resection time and blood loss were investigated in the introductory and stable periods.

Results 

The learning curve could be divided into three phases: initial (1–20 cases), plateau (21–30), and stable (31–50). Resection time with lymph node dissection was significantly longer during the introductory period (initial and plateau periods) (P < 0.01) but not the stable phase (P = 0.51). Multivariate analysis revealed that patients with pancreatitis had longer resection times and massive blood loss in both the introductory and stable periods (stable phase). High visceral fat area was also significantly related to massive blood loss in the introductory period (P = 0.04).

Conclusions

Hepatopancreatobiliary surgeons need more than 30 cases until LPD becomes stable. Lymph node dissection and patients with high visceral fat area and concomitant pancreatitis should be avoided during the introductory period of the learning curve.
Impact of eosinophil-peroxidase (EPX) deficiency on eosinophil structure and function in mouse airways
Authors: Percopo Caroline M , Krumholz Julia O , Fischer Elizabeth R , Kraemer Laura S , Ma Michelle , Laky Karen , Rosenberg Helene F
Published: October 2018

Eosinophil peroxidase (EPX) is a major constituent of the large cytoplasmic granules of both human and mouse eosinophilic leukocytes. Human EPX deficiency is a rare, autosomal-recessive disorder limited to the eosinophil lineage. Our intent was to explore the impact of EPX gene deletion on eosinophil content, structure, and function. In response to repetitive intranasal challenge with a filtrate of the allergen, Alternaria alternata, we found significantly fewer eosinophils peripherally and in the respiratory tracts of EPX−/− mice compared to wild-type controls; furthermore, both the major population (Gr1−/lo) and the smaller population of Gr1hi eosinophils from EPX−/− mice displayed lower median fluorescence intensities (MFIs) for Siglec F. Quantitative evaluation of transmission electron micrographs of lung eosinophils confirmed the relative reduction in granule outer matrix volume in cells from the EPX−/− mice, a finding analogous to that observed in human EPX deficiency. Despite the reduced size of the granule matrix, the cytokine content of eosinophils isolated from allergen-challenged EPX−/− and wild-type mice were largely comparable to one another, although the EPX−/− eosinophils contained reduced concentrations of IL-3. Other distinguishing features of lung eosinophils from allergen-challenged EPX−/− mice included a reduced fraction of surface TLR4+ cells and reduced MFI for NOD1. Interestingly, the EPX gene deletion had no impact on eosinophil-mediated clearance of gram-negative Haemophilus influenzae from the airways. As such, although no clinical findings have been associated with human EPX deficiency, our findings suggest that further evaluation for alterations in eosinophil structure and function may be warranted.

Eosinophils from the lungs of allergen-challenged EPX−/− mice display differential expression of Siglec F and maintain reduced quantities of IL-3.
Disrupted functional connectivity and activity in the white matter of the sensorimotor system in patients with pontine strokes
Authors: Wang Jingjuan , Yang Zhipeng , Zhang Miao , Shan Yi , Rong Dongdong , Ma Qingfeng , Liu Hesheng , Wu Xi , Li Kuncheng , Ding Zhaohua , Lu Jie
Published: October 2018

Background

White matter (WM) blood oxygenation level‐dependent (BOLD) signals are reported to be related to neural activity. However, sensitivity of WM BOLD signals to disease remains unclear.

Purpose

To investigate WM BOLD signal changes, directional variations of resting‐state correlations in sensorimotor system in patients with pontine strokes, and to determine the relationship between WM BOLD signals and motor deficits.

Study Type

Prospective.

Subjects

Ethical approval was obtained from the local Ethics Committee and each participant gave written informed consent. Sixteen patients with focal pontine lesions and 16 age‐matched control subjects were included.

Field Strength/Sequence

3.0T T1‐weighted anatomic images using a 3D magnetization‐prepared rapid gradient‐echo sequence. Resting‐state fMRI images using gradient‐echo echo‐planar imaging sequence. Diffusion‐weighted images using single‐shot spin‐echo diffusion echo‐planar imaging.

Assessment

Relevant WM tracts in the sensorimotor system by region of interest‐wise analysis were identified. Power spectra of BOLD signals and anisotropy of resting‐state correlations were measured in sensorimotor system and compared between two groups. Their relationships with clinical scores were analyzed.

Statistical Tests

Two‐sample t‐test; partial correlation analysis.

Results

Power spectra of BOLD signals in nerve tracts on the ipsilesional side were significantly decreased (P < 0.05). Compared with that in healthy subjects, the anisotropy of resting‐state correlations along identified WM tracts was decreased in the thalamus‐dorsolateral prefrontal cortex bundle on the contralesional side, and all nerve tracts on the ipsilesional side. Partial least squares regression analysis showed the predicted outcome scores correlated significantly with actual Fugl‐Meyer scores (R2 = 0.944, P = 0.013).

Data Conclusion

Our findings suggest that disrupted activity and functional connectivity in WM areas of the sensorimotor system can be detected in pontine strokes, and may serve as a biomarker for motor function prediction.

Level of Evidence: 2

Technical Efficacy: Stage 2

J. Magn. Reson. Imaging 2019;49:478–486.
Absolute Quantification of Phosphor‐Containing Metabolites in the Liver Using 31P MRSI and Hepatic Lipid Volume Correction at 7T Suggests No Dependence on Body Mass Index or Age
Authors: Pfleger Lorenz , Gajdošík Martin , Wolf Peter , Smajis Sabina , Fellinger Paul , Kuehne Andre , Krumpolec Patrik , Trattnig Siegfried , Winhofer Yvonne , Krebs Michael , Krššák Martin , Chmelík Marek
Published: October 2018

Background

Hepatic disorders are often associated with changes in the concentration of phosphorus‐31 (31P) metabolites. Absolute quantification offers a way to assess those metabolites directly but introduces obstacles, especially at higher field strengths (B0 ≥ 7T).

Purpose

To introduce a feasible method for in vivo absolute quantification of hepatic 31P metabolites and assess its clinical value by probing differences related to volunteers' age and body mass index (BMI).

Study Type

Prospective cohort.

Subjects/Phantoms

Four healthy volunteers included in the reproducibility study and 19 healthy subjects arranged into three subgroups according to BMI and age. Phantoms containing 31P solution for correction and validation.

Field Strength/Sequence

Phase‐encoded 3D pulse‐acquire chemical shift imaging for 31P and single‐volume 1H spectroscopy to assess the hepatocellular lipid content at 7T.

Assessment

A phantom replacement method was used. Spectra located in the liver with sufficient signal‐to‐noise ratio and no contamination from muscle tissue, were used to calculate following metabolite concentrations: adenosine triphosphates (γ‐ and α‐ATP); glycerophosphocholine (GPC); glycerophosphoethanolamine (GPE); inorganic phosphate (Pi); phosphocholine (PC); phosphoethanolamine (PE); uridine diphosphate‐glucose (UDPG); nicotinamide adenine dinucleotide‐phosphate (NADH); and phosphatidylcholine (PtdC). Correction for hepatic lipid volume fraction (HLVF) was performed.

Statistical Tests

Differences assessed by analysis of variance with Bonferroni correction for multiple comparison and with a Student's t‐test when appropriate.

Results

The concentrations for the young lean group corrected for HLVF were 2.56 ± 0.10 mM for γ‐ATP (mean ± standard deviation), α‐ATP: 2.42 ± 0.15 mM, GPC: 3.31 ± 0.27 mM, GPE: 3.38 ± 0.87 mM, Pi: 1.42 ± 0.20 mM, PC: 1.47 ± 0.24 mM, PE: 1.61 ± 0.20 mM, UDPG: 0.74 ± 0.17 mM, NADH: 1.21 ± 0.38 mM, and PtdC: 0.43 ± 0.10 mM. Differences found in ATP levels between lean and overweight volunteers vanished after HLVF correction.

Data Conclusion

Exploiting the excellent spectral resolution at 7T and using the phantom replacement method, we were able to quantify up to 10 31P‐containing hepatic metabolites. The combination of 31P magnetic resonance spectroscopy imaging data acquisition and HLVF correction was not able to show a possible dependence of 31P metabolite concentrations on BMI or age, in the small healthy population used in this study.

Level of Evidence: 2

Technical Efficacy: Stage 1

J. Magn. Reson. Imaging 2019;49:597–607.
PET/MRI in Breast Cancer
Authors: Pujara Akshat C. , Kim Eric , Axelrod Deborah , Melsaether Amy N.
Published: October 2018

Positron emission tomography / magnetic resonance imaging (PET/MRI) is an emerging imaging technology that allows for the acquisition of multiple MRI parameters simultaneously with PET data. In this review, we address the technical requirements of PET/MRI including protocols and tracers, the potential of integrated localized breast PET/MRI exams, and possible applications of whole‐body PET/MRI in breast cancer patients. Currently, PET/MRI can be performed on sequential and integrated PET/MRI scanners but, as not all practices can access these dedicated machines, several studies look at PET and MRI exams that are performed separately on separate scanners within a short time frame. This practice likely provides similar clinical data, although exact colocalization for iso‐voxel analysis, currently performed only in research, is not possible. In PET/MRI, the MRI sequences are flexible and can be customized according to the aim of the exam. The most commonly used radiotracer is 18F‐FDG; however, tracers that image hypoxia and drug targets such as estrogen receptors and HER2 are in development and may increase the utility of PET/MRI. For dedicated breast PET/MRI, a potential advantage over standard breast MRI alone may be the complementary sensitivities of MRI for extent of disease within the breast and PET for axillary and internal mammary nodal metastases. Moreover, layers of multiparametric MRI and PET metrics derived from the index lesion are being investigated as predictors of response to neoadjuvant therapy. These data may eventually be able to be quantified and mined in a way that furthers radiomics and also precision medicine. Finally, in whole‐body imaging of breast cancer patients, single‐institution studies have found that PET/MRI detects more metastases than PET at about half the radiation dose, although a survival benefit has not been shown. For now, whole‐body PET/MRI in breast cancer patients may be most relevant for young patients who may undergo serial surveillance exams.

Level of Evidence: 3

Technical Efficacy: Stage 2

J. Magn. Reson. Imaging 2019;49:328–342.
Prospective Evaluation of an R2* Method for Assessing Liver Iron Concentration (LIC) Against FerriScan: Derivation of the Calibration Curve and Characterization of the Nature and Source of Uncertainty in the Relationship
Authors: Jhaveri Kartik S. , Kannengiesser Stephan A.R. , Ward Richard , Kuo Kevin , Sussman Marshall S.
Published: October 2018

Background

FerriScan is the method‐of‐choice for noninvasive liver iron concentration (LIC) quantification. However, it has a number of drawbacks including cost and expediency.

Purpose/Hypothesis

To characterize an R2*‐based MRI technique that may potentially be used as an alternative to FerriScan. This was accomplished through the derivation of a calibration curve that characterized the relationship between FerriScan‐derived LIC and R2*. The nature and source of uncertainty in this curve were investigated. It was hypothesized that the source of uncertainty is heterogeneity of LIC across the liver.

Study Type

Prospective.

Subjects

In all, 125 patients (69 women, 56 men) undergoing chelation treatment for iron overload prospectively underwent FerriScan and R2* MRI during the same exam.

Field Strength/Sequence

Pulse sequences included 2D multislice spin‐echo pulse for FerriScan, and a prototype 3D 6‐echo gradient echo acquisition for R2* mapping at 1.5T.

Assessment

A linear calibration curve was derived from the relationship between FerriScan‐derived LIC estimates and R2* through least‐squares fitting.

Statistical Tests

The nature of the uncertainty in the curve was characterized through tests of normality and homoscedasticity. The source of uncertainty was tested by comparing the magnitude of LIC variation over the FerriScan ROI to the observed uncertainty in the R2*‐derived LIC estimates.

Results

A linear relationship between logarithmically transformed FerriScan‐derived LIC and R2* (log{FerriScan‐derived LIC} = 1.029 log{R2*} – 3.822) was confirmed. Uncertainty was random, with a behaviour that was normal and homoscedastic. The source of uncertainty was confirmed as iron heterogeneity across the liver. The nontransformed calibration curve was: FerriScan‐derived LIC = 0.0266⋅R2*, with a constant coefficient‐of‐variation of 0.32.

Data Conclusion

FerriScan and R2* techniques were found to provide equivalent quantification of LIC in this study. Any difference in accuracy or precision was at a level lower than the uncertainty caused by variation in LIC over the liver.

Level of Evidence: 1

Technical Efficacy: Stage 2

J. Magn. Reson. Imaging 2019;49:1467–1474.
Analytical performance of a low‐cost multiplex polymerase chain reaction human papillomavirus genotyping assay for use in Sub‐Saharan Africa
Authors: Samwel Kandali , Kahesa Crispin , Mwaiselage Julius , Gonzalez Daniela , West John T. , Wood Charles , Palefsky Joel , Angeletti Peter C.
Published: October 2018

We have tested a multiplex polymerase chain reaction (PCR) human papillomavirus (HPV) genotyping assay to fill the need for rapid and low‐cost HPV detection in Sub‐Saharan Africa. This method allows high throughput genotyping and simultaneous detection of 14 high‐risk and two low‐risk HPV types, by PCR amplification of HPV DNAs in a single reaction tube. In this study, we describe stepwise experiments to validate the multiplex HPV PCR assay for determination of HPV genotypes from 104 cervical brush samples from Tanzanian women. Assay performance was evaluated by determination of intra‐laboratory reproducibility, sensitivity, and specificity. Further performance was assessed by comparison with the widely accepted and validated HPV My09/My11 amplification and hybridization assay. Statistics; the Cohen kappa (κ) and McNemar P values were used to analyze interobserver and intermethod agreement. Overall concordance between the multiplex and line blot hybridization assays was 99% (per sample) with a κ value equal to 0.95; and 96.49% (per detection event) with a κ value of 0.92. Interobserver reproducibility of the assay per sample was 95.76% with κ of 0.91. These results demonstrate that the multiplex HPV PCR assay has high analytical sensitivity and specificity in detecting as many as 16 different HPV genotypes and that its simplicity and low cost makes it well suited for sub‐Saharan Africa.
Four unequal substep FDTD (4 USS‐FDTD) method with extremely low numerical dispersion error
Authors: Kusaf Mehmet , Oztoprak Abdullah Y.
Published: October 2018

A new unconditionally stable split‐step FDTD method is introduced which has unequal substeps. The ratio of the unequal substeps, τ, is utilized to obtain extremely low anisotropic errors. It is shown that for any set of space step and time step values, there is a τ value which gives zero anisotropic error. Polynomials are obtained in terms of time and space step sizes for τ and the average normalized numerical phase velocity which can be used to correct for anisotropic error and the average numerical phase velocity. The 2 polynomials can be integrated into the simulation programs, so that the user gets an almost unity normalized phase velocity in all directions, for any chosen time step size and space step size. In this way, large time steps up to Nyquist rate can be used. The method is also suitable for multidomain applications, which makes the method very efficient. A further study shows that the method is very wideband, and for 1% dispersion, error bandwidth is larger than 10:1.
Just flip it!—CRT implantation in a patient with dextrocardia and situs inversus totalis
Authors: Steinberg Christian , Deyell Marc W. , Chakrabarti Santabhanu
Published: October 2018

Implantation of a cardiac resynchronization therapy (CRT) device in patients with congenital heart disease may be challenging because of the particular underlying anatomy. We present the case of a right‐sided transvenous implantation of a dual‐chamber CRT‐D device in a patient with situs inversus totalis and mirror image dextrocardia. To facilitate our anatomic orientation and to overcome unusual hand‐eye coordination problems, we decided to flip the fluoroscopic image projection by 180° (right‐left), creating the optical impression of a “normalized” heart position (levocardia). This simple approach allowed us to successfully implant the device using a conventional left‐sided CRT delivery system.
Effects of consecutive monoculture of sweet potato on soil bacterial community as determined by pyrosequencing
Authors: Li Huan , Wang Jinqiang , Liu Qing , Zhou Zhengfeng , Chen Falin , Xiang Dan
Published: October 2018

Soil bacteria play key roles in determining soil health and plant growth. In this study, four sweet potato fields that had been consecutively monocultured for 1, 2, 3, and 4 years were used to investigate the effect of monoculture on soil physicochemical properties and soil bacterial communities. The results revealed that continuous cropping led to a significant decline in soil pH, soil organic carbon, and soil bacterial abundance. Miseq pyrosequencing analysis of 16S rRNA genes revealed that Proteobacteria and Bacteroidetes were the main phyla in the sweet potato monoculture soils, comprising up to 66.24% of the total sequences. The relative abundances of beneficial bacteria, including Actinobacteria, Gemmatimonadetes, Firmicutes, Xanthomonadaceae, Rhodospirillaceae, and Syntrophobacteraceae, as well as their subgroups at the genus and operational taxonomic unit (OTU) levels, decreased considerably as the number of continuous cropping years increased. In contrast, the number of potentially pathogenic bacteria, such as Acidobacteria, Sphingomonadaceae, and Pedobacter accumulated with increasing years. The results also showed the alterations to the bacterial community in the sweet potato monoculture soils were mainly driven by soil pH and soil organic matter. Overall, the decline in soil quality after successive sweet potato monoculture can be attributed to the imbalance in soil properties and soil microbes, including the decrease in soil pH and soil organic carbon, and the enrichment of pathogenic bacteria at the expense of plant‐beneficial bacteria.
Climatological representation of mesoscale convective systems in a dynamically downscaled climate simulation
Authors: Haberlie Alex M. , Ashley Walker S.
Published: October 2018

This research assesses the utility and validity of using simulated radar reflectivity to detect potential changes in linear and nonlinear mesoscale convective system (MCS) occurrence in the Midwest United States between the early and late 21st century using convection‐permitting climate simulation output. These data include a control run and a pseudo‐global warming (PGW) run that is based on RCP 8.5. First, using a novel segmentation, classification, and tracking procedure, MCS tracks are extracted from observed and simulated radar reflectivity. Next, a comparison between observed and the control run MCS statistics is performed, which finds a negative summertime bias that agrees with previous work. Using a convolutional neural network to perform probabilistic predictions, the MCS dataset is further stratified into highly organized, quasi‐linear convective systems (QLCSs)—which can include bow echoes, squall lines, and line echo wave patterns—and generally less‐organized, non‐QLCS events. The morphologically stratified data reveal that the negative MCS bias in this region is largely driven by too few QLCSs. Although comparisons between the control run and a PGW run suggest that all MCS events are less common in the future (including QLCS and non‐QLCS events), these changes are not spatially significant, whereas the biases between the control run and observations are spatially significant. A discussion on the importance and challenges of simulating QLCSs in convection‐permitting climate model runs is provided. Finally, potential avenues of exploration are suggested related to the aforementioned issues.
Downscaling and projection of summer rainfall in Eastern China using a nonhomogeneous hidden Markov model
Authors: Guo Lianyi , Jiang Zhihong , Ding Mei , Chen Weilin , Li Laurent
Published: October 2018

A nonhomogeneous hidden Markov model (NHMM) is used to stochastically simulate summer (June–August) daily precipitations in the middle and low reaches of the Yangtze River in Eastern China, with driving forcing from three global climate models (GCMs). Simulations cover the historical period from 1961 to 2005 and from 2006 to 2100 following the RCP4.5 scenario. The model is first evaluated against data from the regional observation network. The results show that NHMM effectively enhances the ability of GCMs in simulating summer daily rainfall in the region. For future projection at different time horizons of the 21st century, the spectral distribution of regional precipitations (in function of their intensity) shows consistent changes with a decrease of occurrence probability for light rain (<10 mm/day) and an increase for heavy rain (>10 mm/day). Among variables of interest, total precipitation (PRCPTOT), precipitation intensity, the number of rainy days for daily precipitation exceeding 10 mm (R10mm) and 95th percentile of precipitation (P95), all show a gradually increasing trend in the 21st century, and geographically an eastward gradient with smaller increase (or even weak decrease) for the west and larger increase for the east. It is noted that obvious changes occur in the eastern region with 95% significance level, and PRCPTOT or R10mm increases by 40–60% in the late 21st century. Further quantitative assessment is performed for global warming of 1.5 and 2°C. The half‐degree additional warming makes R10mm change by −3.7, 2.4 and 12.1% over western, central and eastern regions, respectively.
Solid confirmation for the origin of the low‐wave stray light in Raman spectra
Authors: Jiao Fei , Dong Xiaofeng , Gong Yan , Chen WeiHua , Wang Yan , Zhang Shu‐Lin
Published: October 2018

The stray light appearing in the low wavenumber region of Raman spectra has long been the intrinsic hindrance in Raman spectroscopy. In this work, we confirmed that the stray light mentioned above originates from the grating secondary maxima of Rayleigh scattering experimentally and theoretically. This result also gives a clear inspiration for the suppression of such kind of stray light.
Coupling Raman spectroscopy and drop tensiometry for in situ monitoring of radical polymerization in a single monomer droplet
Authors: Dropsit Elise , Desbrières Jacques , Chapron David , Hoppe Sandrine , Durand Alain , Bourson Patrice
Published: October 2018

Two complementary analytical techniques, Raman spectroscopy and drop tensiometry, were coupled in an original homemade experimental setup for in situ monitoring of radical polymerization in a single monomer droplet. Homopolymerizations of styrene and methyl methacrylate initiated by 2,2′‐azobisisobutyronitrile in a single droplet surrounded by an aqueous medium containing sodium dodecylsulfate were investigated. Monomer conversion (from Raman spectroscopy) and interfacial properties (interfacial tension and dilational moduli, from drop tensiometry) were simultaneously acquired in situ.
Overview of sample introduction techniques prior to GC for the analysis of volatiles in solid materials
Authors: Asfaw Adissu Alemayehu , Aspromonte Juan , Wolfs Kris , Van Schepdael Ann , Adams Erwin
Published: October 2018

Sample preparation and introduction techniques are very critical steps in gas chromatography analysis and particularly in the analysis of volatiles in solid samples. In these cases, they can be divided into two main categories: direct and indirect approaches, based on how the solid sample is treated, i.e. with and without dissolution (or extraction) of analytes from the solid sample. To enable routine application, coupling with sample preparation techniques (especially solid or solvent‐based microextractions) is needed to achieve automation. Here, an overview of the most common sample introduction techniques for gas chromatography with their advantages and drawbacks is presented and discussed, including references to relevant examples. So, this review can serve as guidance for new users.
Application of solid‐phase microextraction in current biomedical research
Authors: Roszkowska Anna , Miękus Natalia , Bączek Tomasz
Published: October 2018

Extraction of endogenous compounds and drugs and their corresponding metabolites from complex matrices, such as biofluids and solid tissues, requires adequate analytical approach facilitating qualitative and quantitative analysis. To this end, solid‐phase microextraction has been introduced as modern technology that is capable of efficient and high‐throughput extraction of compounds due to its ability to amalgamate sampling, extraction, and pre‐concentration steps, while requiring minimal use of organic solvents. The ability of solid‐phase microextraction to enable analyses on small‐volume biological samples and growing availability of biocompatible solid‐phase microextraction coatings make it a highly useful technology for variety of applications. For example, solid‐phase microextraction is particularly useful for identifying biomarkers in metabolomics studies, and it can be successfully applied in pharmaceutical and toxicological studies requiring the fast and sensitive determination of drug levels, especially those that are present at low levels in biological matrices such as plasma, urine, saliva, and hair. Moreover, solid‐phase microextraction can be directly applied in in vivo studies because this extraction technique is non‐exhaustive and its biocompatible probes offer minimal invasiveness to the analyzed system. In this article, we review recent progress in well‐established solid‐phase microextraction technique for in vitro and in vivo analyses of various metabolites and drugs in clinical, pharmaceutical, and toxicological applications.
Current status and future trends on automated multidimensional separation techniques employing sorbent‐based extraction columns
Authors: Maciel Edvaldo Vasconcelos Soares , de Toffoli Ana Lúcia , Lanças Fernando Mauro
Published: October 2018

Determination of target analytes present in complex matrices requires a suitable sample preparation approach to efficiently remove the analytes of interest from a medium containing several interferers while at the same time preconcentrating them aiming to improve the output signal detection. Online multidimensional solid‐phase separation techniques have been widely used for the analysis of different contaminants in complex matrices such as food, environmental, and biological samples, among others. These online techniques usually consist of two steps performed in two different columns (extraction and analytical column), the first being employed to extract the analytes of interest from the original medium and the latter to separate them from the interferers. The extraction column in multidimensional techniques presents a relevant role since their variations as building material (usually a tube), sorbent material, modes of application, and so on can significantly influence the extraction success. The main features of such columns are subject of constant research aiming improvements directly related to the performance of the separation techniques that utilize multidimensional analysis. The present review highlights the main features of extraction columns online coupled to chromatographic techniques, inclusive for in‐tube solid‐phase microextraction, online solid phase and turbulent flow, aiming the determination of analytes present at very low concentrations in complex matrices. It will critically describe and discuss some of the most common instrumental set up as well as comments on recent applications of these multidimensional techniques. Besides that, the authors have described some properties and enhancements of the extraction columns that are used as first dimension on these systems, such as type of column material (poly (ether ether ketone), fused silica, stainless steel, and other materials) and the way that the extractive phase is accommodated inside the tubing (filled and open tubular). Practical applications of this approach in fields such as environment, food, and bioanalysis are also presented and discussed.
Ultrasound Adds No Benefit to Clinical Exam for Predicting Dehydration in Children With Acute Diarrhea in a Resource‐Limited Setting
Authors: Koeller Eva , Robertson Sarah E. , Garbern Stephanie Chow , Monk Grace , Nasrin Sabiha , Alam Nur H. , Levine Adam C.
Published: October 2018

Objectives

Diarrhea is one of the most common and deadly conditions affecting children, causing over 525,000 deaths annually, largely in resource‐limited settings. Appropriate treatment depends on accurate determination of dehydration status. This study evaluated the accuracy of a new model using clinical and ultrasound measurements for predicting dehydration status in children with acute diarrhea.

Methods

The Dehydration: Assessing Kids Accurately (DHAKA) study was a prospective cohort study of children under 5 years of age with acute diarrhea presenting to the International Centre for Diarrhoeal Disease Research in Dhaka, Bangladesh. Clinical signs and sonographic measurements of the aorta‐to‐inferior vena cava ratio were recorded. Percent weight change with rehydration was used to classify dehydration severity. Logistic regression was used to create a combined DHAKA‐US model based on clinical and sonographic measurements. Area under the curve and calibration slope were used to assess the model's accuracy and compare it to the original DHAKA score model.

Results

A total of 850 children were enrolled, with 736 included in the final analysis. The combined DHAKA‐US model showed equivalent discrimination with the original DHAKA score, with an area under the curve of 0.79 for both models for severe dehydration (95% confidence interval, 0.74–0.84), as well as similar classification (48% versus 50% correctly classified) and calibration (calibration slopes of 0.900 versus 0.904 for presence of any dehydration).

Conclusion

Adding sonographic measurements to the DHAKA score had no effect on discrimination, classification, or calibration when compared to the original DHAKA score. Clinical signs alone may be the most important predictors of dehydration status in children with diarrhea in limited resource settings.
Impact of Age on Sinus Surgery Outcomes
Authors: Lehmann Ashton E. , Scangas George A. , Sethi Rosh K. V. , Remenschneider Aaron K. , El Rassi Edward , Metson Ralph
Published: October 2018

Objectives/Hypothesis

To evaluate the impact of age on patient‐reported quality of life (QOL) following endoscopic sinus surgery (ESS) for chronic rhinosinusitis (CRS).

Study Design

Prospective cohort study.

Methods

Six hundred thirty‐six patients with CRS were recruited from 11 otolaryngologic practices and completed the sinonasal‐specific, 22‐item Sino‐Nasal Outcome Test‐22 (SNOT‐22) and general health‐related EuroQol 5‐Dimension (EQ‐5D) questionnaires at baseline and 12 and 24 months after ESS. Patients were grouped chronologically to determine whether age at time of ESS was associated with clinical outcomes.

Results

Ages ranged from 18 to 80 years (mean ± standard deviation = 48.5 ± 14.4). Improvement was observed in postoperative SNOT‐22 scores at 12 and 24 months for all decades of life. Similar improvements were observed for EQ‐5D‐based health utility value (HUV) scores in all decades of life, except for the eldest cohort (ages 70–80, N = 33), who did not exceed the minimal clinically important difference at either 12 or 24 months following ESS. In regression analysis, age was not associated with sinonasal‐specific outcomes (change in SNOT‐22 scores) at 12 (P = .507) or 24 months (P = .955). In general health‐related outcomes, however, age was significantly associated with change in EQ‐5D‐based HUV scores from baseline to 12 months following ESS after adjusting for patient demographics, comorbidities, and surgical history (P = .049).

Conclusions

This study demonstrates that ESS for adult CRS sufferers offers improved QOL outcomes through the eighth decade of life. The impact of comorbidities on QOL needs to be carefully considered when assessing older patients for sinus surgery.

Level of Evidence

2b Laryngoscope, 128:2681–2687, 2018
Voice Outcomes of Lipoinjection Versus Medialization Laryngoplasty for Nonparalytic Glottic Insufficiency
Authors: M. Dominguez Laura , Villarreal Ricardo , Simpson C. Blake
Published: October 2018

Objective

To compare voice outcomes of autogenous fat injection versus medialization laryngoplasty in patients with glottic insufficiency due to vocal fold paresis or atrophy.

Methods

A retrospective review was performed from 2009 to 2017 of all patients who underwent lipoinjection or medialization laryngoplasty (ML) for glottic insufficiency. Charts were reviewed for demographic information, preoperative diagnosis, surgical intervention, Voice Handicap Index‐10 (VHI‐10) and Glottal Function Index (GFI) scores, follow‐up time (minimum 3 months), and concomitant voice therapy.

Results

Eighty‐three patients were initially identified and limited to 28 based on the inclusion/exclusion criteria. Thirty‐five procedures were performed with a total of 15 fat injections and 20 MLs. The mean age was 60.7 years in the lipoinjection group and 55.6 years in the ML group. There was no significant difference in pretreatment VHI‐10 scores between the two groups. Using the lowest recorded voice scores during the follow‐up period, both groups had a significant decrease (P < 0.05) compared to preoperative scores (VHI‐10: fat decreased from 27.8 to 14.2, ML decreased from 30.5 to 9.1; GFI: fat decreased from 13.7 to 5.27, ML decreased from 13.6 to 4.6). When evaluating the entire follow‐up period (median 19 months in fat group, 16.3 months in ML), only the ML group maintained a significant improvement in VHI‐10 (median delta 14.5) and GFI (median delta 7) compared to preoperative scores.

Conclusion

Although both autogenous fat injection and ML result in improved voice scores in the short term, the effect of fat injection appears to be limited, as evidenced by worsening VHI‐10 and GFI scores over time.

Level of Evidence

4 Laryngoscope, 129:1164–1168, 2019