bluuebunny/crossref_metadata_2025 huggingface dataset:
Ring-like structures in magnetoactive elastomers based on magnetic hard powder
Authors: Stepanov G V , Borin D Yu , Bakhtiiarov A V , Lobanov D A , Storozhenko P A
Published: November 2020

In this study, we report on the experimentally observed phenomenon of ring-like structures formation from chains of magnetic microparticles in magnetoactive elastomers based on magnetic hard powder. In order to find an explanation for the specific macroscopic magnetic properties of composites, microstructural observations on the elastic composite based on a thin layer of magnetic hard particles have been carried out. Particles embedded in such magnetic composites can move inside the matrix with some restrictions and form chain-like structures on being subjected to magnetizing and turn over as first the strength of the external magnetic field decreases and then the polarity of the field switches to opposite. The quantitative parameters of these processes depend on a number of factors including coercivity and remanence of particles, polymer matrix elasticity, and external field intensity. In zero-field, the magnetized particles can assemble into ring-like structures, thus tending to bring the free energy of the overall system to a minimum. The study is primarily aimed to shed a light on understanding the specific magnetic properties of magnetic polymers, such as magnetoactive or magnetorheological elastomers with a magnetic hard filler. Furthermore, the phenomenon of ring-like structures formation can be used for controlled remote patterning of particles in magnetic elastic composite thin films, which is attractive for various applications.
Mechanical behavior of a NiTi superelastic bone plate obtained by investment casting assisted by additive manufacturing
Authors: Da Cruz Gomes Antonio Aristófanes , Grassi Estephanie Nobre Dantas , da Silva Paulo César Sales , de Araújo Carlos José
Published: November 2020

The mechanical behavior of nickel-titanium shape memory alloys (NiTi SMA) presents unique features that benefit the bone fracture healing process: matching elastic modulus ranges, the ability to recover large deformations, and mechanical dissipation capacity. In this sense, this work proposes a new manufacturing process for NiTi SMA bone implants, particularly bone plates: additive manufacturing assisted investment casting (IC). This process delivers near-net NiTi SMA parts with either simple or complex shapes, also allowing a high degree of customization. Four identical NiTi SMA bone plates were manufactured through IC and characterized. Four-point bending tests were performed on the bone plate prototypes to verify their mechanical and fatigue behaviors. The NiTi bone plates have an elastic modulus of the order of 49 GPa at 37 °C and recovered all deformations upon unloading when submitted to four-point bending deflections up to 4 mm. The fatigue life was between 103 and >105, depending on the deflection amplitude. Our next work with this technology will address aspects of cytotoxicity and implantation of the part in animals.
Assessment of the non-linear optical behavior of cells for discrimination between normal and malignant glial cells
Authors: Minaei Soraya Emamgholizadeh , Ghader Alireza , Ardakani Ali Abbasian , Khoei Samideh , Ara Mohammad Hosein Majles
Published: November 2020

Cancer patients who have a diagnosis in the early stage of the disease have better chances for therapy. Thus, development of new diagnostic procedures is needed for the early detection of cancer. Measuring and analyzing the light that is scattered by the cells can be utilized to monitor early variations associated with cancer evolution. The key hypothesis behind this research was the application of the Z-scan method to progress the precision of detecting the C6 glioblastoma multiforme cancer cells and the OLN-93 normal glial cells.

A Nd:YAG CW laser with a wavelength of 532 nm was used. The laser beam passed through the prepared samples and the transmittance power is distinguished by dislocation. Finally, the nonlinear refractive index and the extinction coefficient of the samples were determined.

Our study showed that the extinction coefficient of the C6 and OLN-93 cells were 49 ± 3 and 33 ± 2, respectively. Also, the sign and value of the nonlinear refractive index (n2) for the C6 and OLN-93 cells was −5.44 × 10−7 cm2 w−1 and +6.07 × 10−7 cm2 w−1, respectively. According to this study, the sign of the n2 index for the C6 and OLN-93 cells was negative and positive, respectively.

Our results suggested that the nonlinear refractive index of the cell samples and Z-scan technique could be an applicable means for identifying glial cancer cells from normal cells.
Internal (Factorial) Validity of the ANAM using a Cohort of Woman High-School Soccer Players
Authors: Glutting Joseph J , Davey Adam , Wahlquist Victoria E , Watkins Marley , Kaminski Thomas W
Published: November 2020

Introduction

Computerized neuropsychological testing is a cornerstone of sport-related concussion assessment. Female soccer players are at an increased risk for concussion as well as exposures to repetitive head impacts from heading a soccer ball. Our primary aim was to examine factorial validity of the Automated Neuropsychological Assessment Metrics (ANAM) neuropsychological test battery in computing the multiple neurocognitive constructs it purports to measure in a large cohort of interscholastic female soccer players.

Methods

Study participants included 218 interscholastic female soccer players (age = 17.0±0.7 year; mass = 55.5±6.8 kg; height = 164.7±6.6 cm) drawn from a large (850+) prospective database examining purposeful heading from four area high schools over a 10-year period. The ANAM-2001 measured neurocognitive performance. Three methods were used to identify integral constructs underlying the ANAM: (a) exploratory factor analysis (EFA), (b) first-order confirmatory factor analysis (CFA), and (c) hierarchical CFA.

Results

Neuropsychological phenomena measured by the ANAM-2001 were best reproduced by a hierarchical CFA organization, composed of two lower level factors (Simple Reaction Time, Mental Efficiency) and a single, general composite. Although the ANAM was multidimensional, only the composite was found to possess sufficient construct dimensionality and reliability for clinical score interpretation. Findings failed to uphold suppositions that the ANAM measures seven distinct constructs, or that any of its seven tests provide unique information independent of other constructs, or the composite, to support individual interpretation.

Conclusions

Outcomes infer the ANAM possesses factorial-validity evidence, but only scores from the composite appear to sufficiently internally valid, and reliable, to support applied use by practitioners.
Optimizing the Mastectomy Flap to Improve Aesthetic Outcomes
Authors: Salibian Ara A , Frey Jordan D , Choi Mihye , Karp Nolan S
Published: November 2020

The aesthetics of breast reconstruction inherently rely on both the ablative and reconstructive procedures. Mastectomy flap quality remains one of the most critical factors in determining the success of a reconstruction and its aesthetic outcome. Maintaining the segmental perfusion to the nipple and skin envelope during mastectomy requires preserving the subcutaneous tissue superficial to the breast capsule. Because this layer of tissue varies in thickness among different patients and within each breast, anatomic dissection along the appropriate planes is required rather than a “one-size-fits-all” mentality. A team-based approach between the breast surgeon and plastic surgeon will optimize both the ablative and reconstructive procedures while engaging in a process of shared decision-making with the patient. Preoperative clinical analysis and utilization of imaging to assess individual breast anatomy will help guide mastectomies as well as decisions on reconstructive modalities. Critical assessment of mastectomy flaps is paramount and requires flexibility to adapt reconstructive paradigms intraoperatively to minimize the risk of complications and provide the best aesthetic result.
What Are the Long-Term Aesthetic Issues in Prepectoral Breast Reconstruction?
Authors: Nahabedian Maurice Y
Published: November 2020

Background

Prepectoral placement of prosthetic devices is rapidly becoming the preferred method of breast reconstruction.

Objectives

The objective of this study was to review long-term surgical and aesthetic outcomes following prepectoral prosthetic breast reconstruction.

Methods

The study included 90 patients (139 breasts). Follow-up for all patients ranged from at least 1 year up to a maximum of 4.3 years. Parameters analyzed included preoperative and postoperative breast symmetry, rippling, edge visibility, and capsular contracture, as well as secondary procedures such as fat grafting, implant exchange, contralateral procedures, and autologous flap conversion.

Results

The incidence of breast symmetry, which was noted preoperatively in 84.4% of patients, gradually declined to 68.9% after 1 to 2 years and to 56.7% after 2 to 5 years. Rippling and edge visibility were noted in 19.4% and 12.9% of patients, respectively. Explantation without replacement of the device was performed in 12 breasts (8.6%). Secondary procedures included autologous fat grafting (23.7%), implant replacement (7.2%), conversion to an autologous flap (12.2%), and a contralateral breast procedure in 15 of 41 patients (36.6%). Capsular contracture (grade 3-4) was demonstrated in 14 of 139 breasts (10.1%).

Conclusions

Prepectoral breast reconstruction can provide good to excellent short-term (1-2 years) and longer-term (2-4.3 years) benefits; however, over time, the quality of prepectoral breast reconstruction as well as breast symmetry can change due to various factors.

Level of Evidence: 4
How to Optimize Prepectoral Breast Reconstruction
Authors: Graziano Francis D , Henderson Peter W , Jacobs Jordan , Salzberg C Andrew , Sbitany Hani
Published: November 2020

Prepectoral breast reconstruction has become a popular method of postmastectomy breast reconstruction due to its numerous benefits in properly selected patients. Prepectoral reconstruction, as compared with retropectoral position, offers the advantage of leaving the pectoralis muscle undisturbed and in its original anatomic position, resulting in significantly decreased acute and chronic pain, improved upper extremity strength and range of motion, and avoidance of animation deformity. The use of acellular dermal matrices (ADMs) allows for precise control of the breast pocket, resulting in aesthetic outcomes and high patient satisfaction. ADMs have the added benefit of reducing capsular contracture, especially in the setting of postmastectomy radiation therapy. Although prepectoral breast reconstruction is effective, the breast implant is placed closer to the skin flap with less vascularized soft tissue coverage. Therefore, optimizing outcomes in prepectoral breast reconstruction requires careful patient selection, intraoperative mastectomy flap evaluation, and perioperative surgical algorithms specific to prepectoral reconstruction.
Obesity, kidney dysfunction, and inflammation: interactions in hypertension
Authors: Hall John E , Mouton Alan J , da Silva Alexandre A , Omoto Ana C M , Wang Zhen , Li Xuan , do Carmo Jussara M
Published: November 2020

Obesity contributes 65–75% of the risk for human primary (essential) hypertension (HT) which is a major driver of cardiovascular and kidney diseases. Kidney dysfunction, associated with increased renal sodium reabsorption and compensatory glomerular hyperfiltration, plays a key role in initiating obesity-HT and target organ injury. Mediators of kidney dysfunction and increased blood pressure include (i) elevated renal sympathetic nerve activity (RSNA); (ii) increased antinatriuretic hormones such as angiotensin II and aldosterone; (iii) relative deficiency of natriuretic hormones; (iv) renal compression by fat in and around the kidneys; and (v) activation of innate and adaptive immune cells that invade tissues throughout the body, producing inflammatory cytokines/chemokines that contribute to vascular and target organ injury, and exacerbate HT. These neurohormonal, renal, and inflammatory mechanisms of obesity-HT are interdependent. For example, excess adiposity increases the adipocyte-derived cytokine leptin which increases RSNA by stimulating the central nervous system proopiomelanocortin-melanocortin 4 receptor pathway. Excess visceral, perirenal and renal sinus fat compress the kidneys which, along with increased RSNA, contribute to renin–angiotensin–aldosterone system activation, although obesity may also activate mineralocorticoid receptors independent of aldosterone. Prolonged obesity, HT, metabolic abnormalities, and inflammation cause progressive renal injury, making HT more resistant to therapy and often requiring multiple antihypertensive drugs and concurrent treatment of dyslipidaemia, insulin resistance, diabetes, and inflammation. More effective anti-obesity drugs are needed to prevent the cascade of cardiorenal, metabolic, and immune disorders that threaten to overwhelm health care systems as obesity prevalence continues to increase.
Bezold–Jarisch reflex-mediated asystole during dobutamine stress testing: a case report
Authors: Hossain Nimrah , Hossain Naseem , Al-Sadawi Mohammed , Haq Salman
Published: November 2020

Background

The Bezold–Jarisch reflex (BJR) is a cardioinhibitory parasympathetic response to activation of ventricular mechanoreceptors, which can result in bradycardia, atrioventricular block, or asystole. This phenomenon has been triggered by acute myocardial ischaemia, intra-arterial nitroglycerine use, natriuretic peptides, and with exceptional rarity, in middle-aged women only, by dobutamine infusion during stress echocardiography.

Case summary

We present the case of a 61-year-old woman who suffered a 5.1-s sinus pause during her 20 μg/kg/min infusion of dobutamine. Recovery was immediate following termination of dobutamine infusion. Concurrent echocardiography was normal, and subsequent cardiac catheterization and electrophysiologic study were normal.

Discussion

This is the fifth documented case of a severe BJR causing asystole during dobutamine infusion, which adds to the accumulating evidence supporting the benign nature of the condition.
Childless Aristocrats: Inheritance and the Extensive Margin of Fertility
Authors: Gobbi Paula E , Goñi Marc
Published: November 2020

Using genealogical data of British aristocrats, we show that inheritances can affect childlessness. We study settlements, a contract restricting heirs’ powers and settling bequests for yet-to-be-born generations. Settlements reduced childlessness to the ‘natural’ rate, ensuring aristocratic dynasties’ survival. Our estimation exploits that settlements were signed at the heir’s wedding if the family head lived until this date. Whether the heir was born after a girl provides as-good-as-random assignment into settlements. Next, we develop a theory that reproduces our findings, shows that exponential discounting cannot rationalise inheritance systems restricting heirs and that inheritance systems can emerge endogenously when fertility concerns exist.
Longitudinal Dynamics of Intact HIV Proviral DNA and Outgrowth Virus Frequencies in a Cohort of Individuals Receiving Antiretroviral Therapy
Authors: Falcinelli Shane D , Kilpatrick Kayla W , Read Jenna , Murtagh Ross , Allard Brigitte , Ghofrani Simon , Kirchherr Jennifer , James Katherine S , Stuelke Erin , Baker Caroline , Kuruc JoAnn D , Eron Joseph J , Hudgens Michael G , Gay Cynthia L , Margolis David M , Archin Nancie M
Published: November 2020

Background

The replication-competent human immunodeficiency virus (HIV) reservoir is the major barrier to cure. The quantitative viral outgrowth assay (QVOA), the gold-standard method to quantify replication-competent HIV, is resource intensive, which limits its application in large clinical trials. The intact proviral DNA assay (IPDA) requires minimal cell input relative to QVOA and quantifies both defective and intact proviral HIV DNA, the latter potentially serving as a surrogate marker for replication-competent provirus. However, there are limited cross-sectional and longitudinal data on the relationship between IPDA and QVOA measurements.

Methods

QVOA and IPDA measurements were performed on 156 resting CD4 T-cell (rCD4) samples from 83 antiretroviral therapy-suppressed HIV-positive participants. Longitudinal QVOA and IPDA measurements were performed on rCD4 from 29 of these participants.

Results

Frequencies of intact, defective, and total proviruses were positively associated with frequencies of replication-competent HIV. Longitudinally, decreases in intact proviral frequencies were strikingly similar to that of replication-competent virus in most participants. In contrast, defective proviral DNA frequencies appeared relatively stable over time in most individuals.

Conclusions

Changes in frequencies of IPDA-derived intact proviral DNA and replication-competent HIV measured by QVOA are similar. IPDA is a promising high-throughput approach to estimate changes in the frequency of the replication-competent reservoir.
A Single Center Review of the Dangers of Recreational Fires in the Pediatric Population
Authors: Perinjelil Vinu , Haake Robert Stephen , Ahmed Afroze , Al-Daoud Fadi , Maraqa Tareq , Mercer Leo , Wong Kristoffer , Morris Stephen , Scholten Donald , Sachwani-Daswani Gul
Published: November 2020

The increasing trend of admissions due to recreational fires prompted a 5-year review. The retrospective chart review of pediatric burn injuries from campfires or bonfires treated at a single medical center’s burn unit. The study included children within the ages of 0 to 15 admitted or transferred from January 2012 to December 2016 with first, second, and/or third degree burns by bonfires. These patients accrued burns due to active fires as well as postfire ember contact. Two hundred-eighty nine (289) were pediatric admissions out of which 66 (22.8%) were pediatric admissions associated with recreational fires. The mean annual admission for campfire or bonfire burns was 13 ± .98. The mean age was 4 ± 2.47 years. Gender distribution revealed 21 female and 45 male pediatric patients under the age of 15. From the available data, 8 (12%) of these burns occurred at home in the backyard and 16 (24%) at a public camp or park. Injury mechanisms were more commonly a result of direct contact with hot coals and embers (65%). Falls into open flame accounted for 23% (n = 15) of injuries, and flash flames accounted for 12% of injuries (n = 8). The presence of supervision was unknown in 56%; however, lack of supervision was a factor in 14% of our study population. By gaining a better understanding of the type of injury, mechanism of injury, and the demographic of recreational fire burn victims, policy, and awareness campaigns were instituted in an effort to reduce the incidence of recreational fire burns.
Comparison of the Effect of Insecticides on Bumble Bees (Bombus impatiens) and Mosquitoes (Aedes aegypti and Culex quinquefasciatus) by Standard Mosquito Research Methods
Authors: McGregor Bethany L , Giordano Bryan V , Runkel Alfred E , Nigg Herbert N , Nigg H Lee , Burkett-Cadena Nathan D
Published: November 2020

Mosquito control districts in the United States are limited to two main classes of adulticides, pyrethroids and organophosphates, to control mosquitoes. Two adulticides used to control domestic mosquitoes are Fyfanon EW (malathion, organophosphate) and DeltaGard (deltamethrin, pyrethroid). While the effect of these pesticides on European honeybees (Apis mellifera L., Hymenoptera: Apidae) has been investigated, effects on native pollinators need additional research. The purpose of this study was to investigate the acute nontarget effects of these pesticides on Bombus impatiens Cresson (Hymenoptera: Apidae), a native North American bumble bee species, and compare these effects to wild and laboratory strains of mosquitoes (Aedes aegypti (L.) and Culex quinquefasciatus Say, Diptera: Culicidae) through field and laboratory assays. Bombus impatiens was found to be resistant to Fyfanon EW (x̅ = 6.7% mortality at 50-µg malathion per bottle) at levels that caused significant mortality to study mosquitoes (86.2 ≥ x̅ ≥ 100% mortality) in laboratory bottle bioassays. Comparatively, B. impatiens demonstrated greater mortality to DeltaGard (93.3%) at 2.5-µg deltamethrin/bottle than any mosquito colony assayed (14.1 ≥ x̅ ≥ 87.0% mortality). Only DeltaGard was tested in field applications. In the field, we observed acute effects of DeltaGard on mosquitoes and B. impatiens at 25- and 75-m distance from a truck-mounted ultra-low volume fogger, although treatment effects were not significant for B. impatiens. Additional wild-caught nontarget mortality to DeltaGard field trials was also evaluated. This study indicated that common mosquito control adulticides do cause nontarget mortality to B. impatiens but that impacts are variable depending on pesticide and further studies are needed.
Evaluation of Sticky Traps for Monitoring Scolothrips sexmaculatus (Thysanoptera: Thripidae) and Stethorus punctum (Coleoptera: Coccinellidae) as Predators of Spider Mites in California Almonds
Authors: Haviland David R , Rill Stephanie M , Gordon Chelsea A
Published: November 2020

Changes in almond production practices have caused sixspotted thrips, Scolothrips sexmaculatus Pergande, and the coccinellid beetle, Stethorus punctum LeConte, to replace phytoseiid mites as the dominant predators of spider mites in California almonds. We conducted a series of field studies to evaluate nine commercially available adhesive traps for S. sexmaculatus and S. punctum and found that the yellow strip trap was the most effective, least expensive, and easy to use. At peak population levels, individual cards routinely caught >1,000 S. sexmaculatus and >100 S. punctum trap−1 week−1. We documented that larger traps collected more S. sexmaculatus, and more S. sexmaculatus per square area, suggesting that the trap surface was attractive. We determined the number of traps needed to have 50, 70, and 90% confidence that the averages of trap captures were within 10, 30, and 50% of the population mean. Two yellow strip traps per orchard provided 90% confidence that trap captures were within 50% of the population mean if there were an average of 16.0 S. sexmaculatus trap−1 week−1 or 7.9 S. punctum trap−1 week−1. Populations required to attain the same levels of confidence using four traps per orchard were 3.9 S. sexmaculatus and 2.9 S. punctum trap−1 week−1. We conclude that use of the yellow strip trap to monitor for natural enemies, in combination with leaf samples for spider mites, has the potential to improve integrated pest management programs for spider mites, and assist future research to understand the biology and phenology of both predator species.
Frame-validity Games and Lower Bounds on the Complexity of Modal Axioms
Authors: Balbiani Philippe , Fernández-Duque David , Herzig Andreas , Iliev Petar
Published: November 2020

We introduce frame-equivalence games tailored for reasoning about the size, modal depth, number of occurrences of symbols and number of different propositional variables of modal formulae defining a given frame property. Using these games, we prove lower bounds on the above measures for a number of well-known modal axioms; what is more, for some of the axioms, we show that they are optimal among the formulae defining the respective class of frames.
MxMPK6-2-bHLH104 interaction is involved in reactive oxygen species signaling in response to iron deficiency in apple rootstock
Authors: Li Duyue , Sun Qiran , Zhang Guifen , Zhai Longmei , Li Keting , Feng Yi , Wu Ting , Zhang Xinzhong , Xu Xuefeng , Wang Yi , Han Zhenhai
Published: November 2020

Iron (Fe) is a trace element necessary for plant growth. Many land plants have evolved a set of mechanisms associated with the Fe absorption process to deal with the problem of insufficient Fe supply in the soil. During Fe absorption, reactive oxygen species (ROS) can be used as a signal to initiate a response to stress caused by Fe deficiency. However, the molecular mechanisms underlying the involvement of ROS in the Fe deficiency stress response remains unclear. In this study, we have identified a kinase, MxMPK6-2, from Malus xiaojinensis, an apple rootstock that is highly efficient at Fe absorption. MxMPK6-2 has been shown to be responsive to ROS signals during Fe deficiency, and MxMPK6-2 overexpression in apple calli enhanced its tolerance to Fe deficiency. We further screened for proteins in the Fe absorption pathway and identified MxbHLH104, a transcription factor which interacts with MxMPK6-2. MxbHLH104 can be phosphorylated by MxMPK6-2 in vivo, and we confirmed that its phosphorylation increased Fe absorption in apple calli under Fe deficiency, with the presence of ROS promoting this process. Overall, we have demonstrated that MxMPK6-2 is responsive to ROS signaling during Fe deficiency, and is able to control its response by regulating MxbHLH104.
The nature of the modification at position 37 of tRNAPhe correlates with acquired taxol resistance
Authors: Pan Yu , Yan Tong-Meng , Wang Jing-Rong , Jiang Zhi-Hong
Published: November 2020

Acquired drug resistance is a major obstacle in cancer therapy. Recent studies revealed that reprogramming of tRNA modifications modulates cancer survival in response to chemotherapy. However, dynamic changes in tRNA modification were not elucidated. In this study, comparative analysis of the human cancer cell lines and their taxol resistant strains based on tRNA mapping was performed by using UHPLC–MS/MS. It was observed for the first time in all three cell lines that 4-demethylwyosine (imG-14) substitutes for hydroxywybutosine (OHyW) due to tRNA-wybutosine synthesizing enzyme-2 (TYW2) downregulation and becomes the predominant modification at the 37th position of tRNAphe in the taxol-resistant strains. Further analysis indicated that the increase in imG-14 levels is caused by downregulation of TYW2. The time courses of the increase in imG-14 and downregulation of TYW2 are consistent with each other as well as consistent with the time course of the development of taxol-resistance. Knockdown of TYW2 in HeLa cells caused both an accumulation of imG-14 and reduction in taxol potency. Taken together, low expression of TYW2 enzyme promotes the cancer survival and resistance to taxol therapy, implying a novel mechanism for taxol resistance. Reduction of imG-14 deposition offers an underlying rationale to overcome taxol resistance in cancer chemotherapy.
Cell Therapy for Stroke: A Mechanistic Analysis
Authors: Gu Ben Jiahe , Kung David K , Chen Han-Chiao Isaac
Published: November 2020

Cell therapy has been widely recognized as a promising strategy to enhance recovery in stroke survivors. However, despite an abundance of encouraging preclinical data, successful clinical translation remains elusive. As the field continues to advance, it is important to reexamine prior clinical trials in the context of their intended mechanisms, as this can inform future preclinical and translational efforts. In the present work, we review the major clinical trials of cell therapy for stroke and highlight a mechanistic shift between the earliest studies, which aimed to replace dead and damaged neurons, and later ones that focused on exploiting the various neuromodulatory effects afforded by stem cells. We discuss why both mechanisms are worth pursuing and emphasize the means through which cell replacement can still be achieved.
SARS-CoV-2 Serologic Assay Needs for the Next Phase of the US COVID-19 Pandemic Response
Authors: Gundlapalli Adi V , Salerno Reynolds M , Brooks John T , Averhoff Francisco , Petersen Lyle R , McDonald L Clifford , Iademarco Michael F ,   CDC COVID-19 Response, Carroll Yulia I , Gorwitz Rachel , Lin-Gibson Sheng , Wang Lili , Pinto Ligia A
Published: November 2020

Background

There is a need for validated and standardized severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) quantitative immunoglobulin G (IgG) and neutralization assays that can be used to understand the immunology and pathogenesis of SARS-CoV-2 infection and support the coronavirus disease 2019 (COVID-19) pandemic response.

Methods

Literature searches were conducted to identify English language publications from peer-reviewed journals and preprints from January 2020 through November 6, 2020. Relevant publications were reviewed for mention of IgG or neutralization assays for SARS-CoV-2, or both, and the methods of reporting assay results.

Results

Quantitative SARS-CoV-2 IgG results have been reported from a limited number of studies; most studies used in-house laboratory-developed tests in limited settings, and only two semiquantitative tests have received US Food and Drug Administration (FDA) Emergency Use Authorization (EUA). As of November 6, 2020, there is only one SARS-CoV-2 neutralization assay with FDA EUA. Relatively few studies have attempted correlation of quantitative IgG titers with neutralization results to estimate surrogates of protection. The number of individuals tested is small compared with the magnitude of the pandemic, and persons tested are not representative of disproportionately affected populations. Methods of reporting quantitative results are not standardized to enable comparisons and meta-analyses.

Conclusions

Lack of standardized SARS-CoV-2 quantitative IgG and neutralization assays precludes comparison of results from published studies. Interassay and interlaboratory validation and standardization of assays will support efforts to better understand antibody kinetics and longevity of humoral immune responses postillness, surrogates of immune protection, and vaccine immunogenicity and efficacy. Public–private partnerships could facilitate realization of these advances in the United States and worldwide.
Learning about the Neighborhood
Authors: Gao Zhenyu , Sockin Michael , Xiong Wei
Published: November 2020

We develop a model to analyze information aggregation and learning in housing markets. Households enter a neighborhood by buying houses and consuming each other’s final goods. In the presence of pervasive informational frictions, housing prices serve as important signals to households and capital producers about the neighborhood’s economic strength. Our model provides a novel amplification mechanism in which noise from housing markets propagates throughout the local economy via learning because of the complementarity in households’ decisions, distorting migration into the neighborhood and the supply of capital and labor. We provide consistent evidence based on the recent U.S. housing cycle.
In Uteroand Lactational Exposure to an Environmentally Relevant Mixture of Brominated Flame Retardants Induces a Premature Development of the Mammary Glands
Authors: Gouesse Rita-Josiane , Dianati Elham , McDermott Alec , Wade Michael G , Hales Barbara , Robaire Bernard , Plante Isabelle
Published: November 2020

In utero and prepubertal development of the mammary glands occurs minimally in a hormone independent manner until puberty where maturation of the hypothalamic-pituitary-gonadal axis drives an extensive remodeling. Nevertheless, because the immature glands contain functional hormone receptors, they are especially vulnerable to the effects of endocrine disruptors, such as brominated flame retardants (BFRs). BFRs are widespread chemicals added to household objects to reduce their flammability, and to which humans are ubiquitously exposed. We previously reported that in utero and lactational exposure to BFRs resulted in an impaired mammary gland development in peripubertal animals. Here, we assessed whether BFR-induced disruption of mammary gland development could manifest earlier in life. Dams were exposed prior to mating until pups’ weaning to a BFR mixture (0, 0.06, 20, or 60 mg/kg/day) formulated according to levels found in house dust. The mammary glands of female offspring were collected at weaning. Histo-morphological analyses showed that exposure to 0.06 mg/kg/day accelerates global epithelial development as demonstrated by a significant increase in total epithelial surface area, associated with a tendency to increase of the ductal area and thickness, and of lumen area. Significant increases of the Ki67 cell proliferation index and of the early apoptotic marker cleaved caspase-9 were also observed, as well as an upward trend in the number of thyroid hormone receptor α1 positive cells. These molecular, histologic, and morphometric changes are suggestive of accelerated pubertal development. Thus, our results suggest that exposure to an environmentally relevant mixture of BFRs induces precocious development of the mammary gland.
Ovarian Suppression for Adjuvant Treatment of Hormone-Positive Early Breast Cancer
Authors: Greenslade Rebecca
Published: November 2020

Editor's note: The mission of Cochrane Nursing is to provide an international evidence base for nurses involved in delivering, leading, or researching nursing care. Cochrane Corner provides summaries of recent systematic reviews from the Cochrane Library. For more information, see https://nursing.cochrane.org.
First Oral Drug Approved for Spinal Muscular Atrophy
Authors: Aschenbrenner Diane S.
Published: November 2020

Risdiplam (Evrysdi) is the first oral drug approved to treat spinal muscular atrophy. Although it treats the disease symptoms, it does not cure the disease.
Adolescent Health: Think, Act, Grow
Authors: Ortelli Tracy A.
Published: November 2020

A framework for action to improve teens' well-being.
Managing Home Infusion Therapy
Authors: Fields Bronwyn E. , Whitney Robin L. , Bell Janice F.
Published: November 2020

This article is part of a series, Supporting Family Caregivers: No Longer Home Alone, published in collaboration with the AARP Public Policy Institute. Results of focus groups, conducted as part of the AARP Public Policy Institute's No Longer Home Alone video project, supported evidence that family caregivers aren't given the information they need to manage the complex care regimens of family members. This series of articles and accompanying videos aims to help nurses provide caregivers with the tools they need to manage their family member's health care at home. Nurses should read the articles first, so they understand how best to help family caregivers. Then they can refer caregivers to the informational tear sheet—Information for Family Caregivers—and instructional videos, encouraging them to ask questions. For additional information, see Resources for Nurses.
An update on the microbiome in vasculitis
Authors: Tariq Shahna , Clifford Alison H.
Published: November 2020

Purpose of review

To summarize recent evidence regarding the presence and potential role of the microbiome in systemic vasculitides.

Recent findings

Microbiomic descriptions are now available in patients with small, medium and large vessel vasculitis. The majority of studies have evaluated gastrointestinal inhabitants, with a smaller number of studies describing the nasal, pulmonary or vascular microbiomes. Most published studies are observational and cross-sectional. Dysbiosis is seen frequently in vasculitis patients with reduced microbial diversity observed in nasal, fecal and vascular samples compared with disease and/or healthy controls. Predominant bacteria vary, but overall, patients with vasculitis tend to have more pathogenic and less commensal bacteria in active disease. In the few longitudinal studies available, improvement or resolution of dysbiosis has been observed following vasculitis treatment and improved disease activity.

Dysbiosis and reduced microbial diversity has been identified in patients with small, medium and large vessel vasculitis. Although limited data suggests microbiomes may ‘normalize’ following immunosuppression, cause or effect cannot be determined. It is hypothesized that microbial disruption in a genetically susceptible individual may trigger excessive host immune activation and vasculitis; however, larger studies with longitudinal and translational design are needed to further our current understanding.
Role of adipose tissues in osteoarthritis
Authors: Zapata-Linares Natalia , Eymard Florent , Berenbaum Francis , Houard Xavier
Published: November 2020

Purpose of review

Epidemiologic studies reveal that the link between obesity and osteoarthritis cannot be uniquely explained by overweight-associated mechanical overload. For this reason, much attention focuses on the endocrine activity of adipose tissues. In addition to the systemic role of visceral and subcutaneous adipose tissues, many arguments highlight the involvement of local adipose tissues in osteoarthritis.

Recent findings

Alteration in MRI signal intensity of the infrapatellar fat pad may predict both accelerated knee osteoarthritis and joint replacement. In this context, recent studies show that mesenchymal stromal cells could play a pivotal role in the pathological remodelling of intra-articular adipose tissues (IAATs) in osteoarthritis. In parallel, recent findings underline bone marrow adipose tissue as a major player in the control of the bone microenvironment, suggesting its possible role in osteoarthritis.

The recent description of adipose tissues of various phenotypes within an osteoarthritic joint allows us to evoke their direct involvement in the initiation and progression of the osteoarthritic process. We can expect in the near future the discovery of novel molecules targeting these tissues.
Cerebral vasculitis associated with drug abuse
Authors: Younger David S.
Published: November 2020

Purpose of review

To review understand the epidemiology, background, neuropharmacology, and histopathology of literature verified cases, and likely etiopathogenic mechanisms.

Recent findings

There are only a handful of histologically confirmed patients in the literature with cerebral vasculitis because of drug abuse.

There is little justification for invasive laboratory investigation given the ready availability of highly accurate vascular neuroimaging techniques to dictate management, which usually rests upon avoidance of further exposure and minimizing the secondary neurotoxic effects of the abused substances and polypharmacy use.
Effects of Axial Compression and Distraction on Vascular Bud and VEGFA Expression in the Vertebral Endplate of an Ex Vivo Rabbit Spinal Motion Segment Culture Model
Authors: Zhan Jia-Wen , Wang Shang-Quan , Feng Min-Shan , Gao Jing-Hua , Wei Xu , Yu Jie , Yin Xun-Lu , Yin He , Sun Kai , Chen Ming , Xie Rui , Zhang Ping , Zhu Li-Guo
Published: November 2020

Study Design.

An ex vivo study of the rabbit's vertebral endplate.

Objective.

The aim of this study was to assess the effect of axial compression and distraction on vascular buds and vascular endothelial growth factor (VEGFA) expression of the vertebral endplate (VEP).

Summary of Background Data.

The abnormal load can lead to intervertebral disc degeneration (IDD), whereas axial distraction can delay this process. The effects of different mechanical loads on the intervertebral disc (IVD) have been hypothesized to be related to changes in the vascular buds of the VEP; moreover, the process that might involve the vascular endothelial growth factor (VEGF) within the VEP.

Methods.

Rabbit spinal segments (n = 40) were harvested and randomly classified into four groups: Control group, no stress was applied; Group A, a constant compressive load applied; Group B, compression load removed for a fixed time daily on a continuous basis, and substituted with a distraction load for 30 minutes; and Group C, compression removed for 30 minutes for a fixed period daily on a continuous basis. Tissue specimens were collected before the culture (day 0) and on day 14 post-culture of each group for analysis of IVDs’ morphology, and protein and mRNA expression of Aggrecan, COL2al, VEGFA, and vascular endothelial growth factor receptor 2 of the VEPs.

Results.

Application of axial distraction and dynamic load compression significantly delayed time- and constant compression-mediated VEP changes and IDD. Moreover, the degree of degeneration was associated with loss of vascular buds, as well as the downregulation of VEGFA and its receptor.

Conclusion.

The regulation of vascular buds and VEGF expression in the VEP represents one of the mechanisms of axial distraction and dynamic loading.

Level of Evidence: N/A
Telemedicine in the Evaluation and Management of Neurosurgical Spine Patients
Authors: Greven Alexander C.M. , McGinley Beau M. , Guisse Ndeye F. , McGee Lynessa J. , Pirkle Sarah , Malcolm James G. , Rodts Gerald E. , Refai Daniel , Gary Matthew F.
Published: November 2020

Study Design.

Retrospective questionnaire study of all patients seen via telemedicine during the COVID-19 pandemic at a large academic institution.

Objective.

This aim of this study was to compare patient satisfaction of telemedicine clinic to in-person visits; to evaluate the preference for telemedicine to in-person visits; to assess patients’ willingness to proceed with major surgery and/or a minor procedure based on a telemedicine visit alone.

Summary of Background Data.

One study showed promising utility of mobile health applications for spine patients. No studies have investigated telemedicine in the evaluation and management of spine patients.

Methods.

An 11-part questionnaire was developed to assess the attitudes toward telemedicine for all patients seen within a 7-week period during the COVID-19 crisis. Patients were called by phone to participate in the survey. χ2 and the Wilcoxon Rank-Sum Test were performed to determine significance.

Results.

Ninety-five percent were “satisfied” or “very satisfied” with their telemedicine visit, with 62% stating it was “the same” or “better” than previous in-person appointments. Patients saved a median of 105 minutes by using telemedicine compared to in-person visits. Fifty-two percent of patients have to take off work for in-person visits, compared to 7% for telemedicine. Thirty-seven percent preferred telemedicine to in-person visits. Patients who preferred telemedicine had significantly longer patient-reported in-person visit times (score mean of 171) compared to patients who preferred in-person visits (score mean of 137, P = 0.0007). Thirty-seven percent of patients would proceed with surgery and 73% would proceed with a minor procedure based on a telemedicine visit alone.

Conclusion.

Telemedicine can increase access to specialty care for patients with prolonged travel time to in-person visits and decrease the socioeconomic burden for both patients and hospital systems. The high satisfaction with telemedicine and willingness to proceed with surgery suggest that remote visits may be useful for both routine management and initial surgical evaluation for spine surgery candidates.

Level of Evidence: 3
Prolonged postoperative cerebral oxygen desaturation after cardiac surgery
Authors: Cioccari Luca , Bitker Laurent , Toh Lisa , Hacking Douglas , Cutuli Salvatore L. , Osawa Eduardo A. , Yanase Fumitaka , Naorungroj Thummaporn , Luethi Nora , Michalopoulos Adrian , Woo Shanan , Wang Judy , Eastwood Glenn M. , Weinberg Laurence , Bellomo Rinaldo
Published: November 2020

BACKGROUND

Near-infrared spectroscopy (NIRS) is used routinely to monitor cerebral tissue oxygen saturation (SctO2) during cardiopulmonary bypass (CPB) but is rarely employed outside the operating room. Previous studies indicate that patients are at risk of postoperative cerebral oxygen desaturation after cardiac surgery.

OBJECTIVES

We aimed to assess perioperative and postoperative changes in NIRS-derived SctO2 in cardiac surgery patients.

DESIGN

Prospective observational study.

SETTING

The study was conducted in a tertiary referral university hospital in Australia from December 2017 to December 2018.

PATIENTS

We studied 34 adult patients (70.6% men) undergoing cardiac surgery requiring CPB and a reference group of 36 patients undergoing non-cardiac surgical procedures under general anaesthesia.

MAIN OUTCOME MEASURES

We measured SctO2 at baseline, during and after surgery, and then once daily until hospital discharge, for a maximum of 7 days. We used multivariate linear mixed-effects modelling to adjust for all relevant imbalances between the two groups.

RESULTS

In the cardiac surgery group, SctO2 was 63.7% [95% confidence interval (CI), 62.0 to 65.5] at baseline and 61.0% (95% CI, 59.1 to 62.9, P = 0.01) on arrival in the ICU. From day 2 to day 7 after cardiac surgery, SctO2 progressively declined. At hospital discharge, SctO2 was significantly lower than baseline, at 53.5% (95% CI, 51.8 to 55.2, P < 0.001). In the reference group, postoperative SctO2 was not significantly different from baseline. On multivariable analysis, cardiac surgery, peripheral vascular disease and time since the operation were associated with greater cerebral desaturation, whereas higher haemoglobin concentrations were associated with slightly better cerebral oxygenation.

CONCLUSION

After cardiac surgery on CPB, but not after non-cardiac surgery, most patients experience prolonged cerebral desaturation. Such postoperative desaturation remained unresolved 7 days after surgery. The underlying mechanisms and time to resolution of such cerebral desaturations require further investigation.
Adenovirus Infection-associated Central Nervous System Disease in Children
Authors: Zhang Xiao-Fang , Tan Cheng-Bing , Yao Zheng-Xiong , Jiang Li , Hong Si-Qi
Published: November 2020

Background:

Adenovirus (Adv) is a frequent etiology of acute respiratory tract infections. Although rare, neurologic manifestations are known to occur during Adv infection.

Methods:

We retrospectively analyzed clinical, laboratory, outcome and the relationship between clinical characteristics and viral detection results in the cerebrospinal fluid (CSF) in children with Adv-associated central nervous system (CNS) dysfunction.

Results: Twenty-one

(1.5%) cases had Adv-associated CNS manifestations. The median age was 1.4 years and 20 (95%) were less than 5 years of age. Six (28%) were male. The most frequently cited CNS symptoms were altered consciousness (100%) and seizure (14.3%). Fourteen cases (73.7%) had abnormal electroencephalogram examination and 6 cases (37.5%) had abnormal imaging. None of the patients had received cidofovir administration. Twenty children recovered without sequelae and 1 patient died of respiratory failure. Patients with positive Adv polymerase chain reaction (n = 11) presented lower onset age compared with that of patients with negative Adv polymerase chain reaction (n = 10) in the CSF. Clinical manifestation, laboratory findings, imaging studies and electroencephalogram showed no significant difference between the 2 groups.

Conclusion:

Adv is a rare cause of CNS disease in children, mainly causing altered consciousness. Adv was detected in more cases in the respiratory tract than the CSF, but the majority of patients had the virus detected in both. The lack of Adv in the CSF does not exclude CNS involvement. Furthermore, the viral detection results in the CSF do not seem useful as an indicator of the severity of CNS disease.
The Vital Role of a Federally Qualified Community Health Center in New Orleans, Louisiana, During the COVID-19 Pandemic
Authors: Halperin Jason , Conner Katherine , Telleria Christian , Agins Bruce , Butler Isolde
Published: November 2020

Federally qualified health centers (FQHCs) are on the front lines of the COVID-19 pandemic. Their mission of providing essential medical care to underserved populations is now even more vital. CrescentCare, an FQHC in New Orleans, evaluated and tested 3366 patients between March 16 and July 2, with an overall rate of 12% SARS-CoV-2 positivity. The clinic's experience demonstrates how to effectively and rapidly integrate COVID-19 programing, while preserving essential health services. Strategies include developing a walk-in COVID-19 testing site, ensuring appropriate clinical evaluation, providing accurate public health information, and advocating for job safety on behalf of our patients.