ResearchPad - review-papers https://www.researchpad.co Default RSS Feed en-us © 2020 Newgen KnowledgeWorks <![CDATA[Plant receptor-like kinase signaling through heterotrimeric G-proteins]]> https://www.researchpad.co/article/elastic_article_10042 A review of the regulation of plant G-protein signaling by receptor-like kinases, discussing their genetic, functional, and biochemical links with different G-protein components and suggesting the existence of plant-specific signaling mechanisms.

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<![CDATA[Rise of Raman spectroscopy in neurosurgery: a review]]> https://www.researchpad.co/article/N3aa1fe42-502b-469a-bf17-be24bcc1673c

Abstract.

Significance: Although the clinical potential for Raman spectroscopy (RS) has been anticipated for decades, it has only recently been used in neurosurgery. Still, few devices have succeeded in making their way into the operating room. With recent technological advancements, however, vibrational sensing is poised to be a revolutionary tool for neurosurgeons.

Aim: We give a summary of neurosurgical workflows and key translational milestones of RS in clinical use and provide the optics and data science background required to implement such devices.

Approach: We performed an extensive review of the literature, with a specific emphasis on research that aims to build Raman systems suited for a neurosurgical setting.

Results: The main translatable interest in Raman sensing rests in its capacity to yield label-free molecular information from tissue intraoperatively. Systems that have proven usable in the clinical setting are ergonomic, have a short integration time, and can acquire high-quality signal even in suboptimal conditions. Moreover, because of the complex microenvironment of brain tissue, data analysis is now recognized as a critical step in achieving high performance Raman-based sensing.

Conclusions: The next generation of Raman-based devices are making their way into operating rooms and their clinical translation requires close collaboration between physicians, engineers, and data scientists.

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<![CDATA[Hormonal regulation of root hair growth and responses to the environment in Arabidopsis]]> https://www.researchpad.co/article/Na353636e-24ff-48bf-8f0d-948f1353ec84

This review presents a molecular framework for how phytohormones regulate normal root hair development and how this is affected by changes in the rhizosphere, to enable greater understanding of the specialized functions of root hairs and their developmental and environmental plasticity.

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<![CDATA[Molecular networks regulating cell division during Arabidopsis leaf growth]]> https://www.researchpad.co/article/N94b816b0-f5d5-41d0-9355-5be27b1b0874

Numerous genes have been identified that regulate leaf growth, which can be grouped into regulatory modules. Here, we review six important gene modules that affect cell proliferation during leaf development.

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<![CDATA[Same same, but different: growth responses of primary and lateral roots]]> https://www.researchpad.co/article/Nf933f767-86e2-444f-b3c9-bab4a4638124

We highlight the similarities and differences in primary and lateral root growth, focusing on the differential impact that phytohormones and environmental cues have on these. 

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<![CDATA[Prevalence of intimidation, harassment, and discrimination among resident physicians: a systematic review and meta-analysis]]> https://www.researchpad.co/article/Ne7b4e0d7-c7b5-4329-8525-affe5b02da15

Background

The aim of this study was to establish the prevalence of intimidation, harassment, and discrimination (IHD) reported by resident physicians during their training, to identify factors associated with reported IHD, and to identify adverse sequalae associated with IHD.

Methods

This review followed the PRISMA guidelines. Eight electronic databases were searched for cross-sectional studies reporting the prevalence of IHD among resident physicians. Prevalence estimates were pooledacross studies using random-effects meta-analysis, with variance stabilization using Tukey double arcsine transformation. Heterogeneity was assessed with forest plots, the I2 statistic, subgroup analyses, and multivariate meta-regression.

Results

52 cross-sectional studies were included in the meta-analysis. The overall pooled prevalence of IHD was 64.1% (95% confidence interval [CI], 51.0-77.1). Verbal, physical, and sexual IHD were the most common forms of IHD reported by residents. Training status (55.5%), gender (41.7%), and ethnicity (20.6%) were the most commonly cited risk factors for IHD. The most common sources of IHD were relatives/friends of patients, nurses, and patients (cited by 50.7%, 47.8, and 41.7%, respectively).

Conclusions

The prevalence of IHD among resident physicians is high and associated with multiple negative outcomes, including burnout. Despite the availability of multiple anti-IHD interventions, reports of IHD appear to be rising in many residency programs.

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<![CDATA[Augmented reality in medical education: a systematic review]]> https://www.researchpad.co/article/Nf01c0611-e4c7-4a2f-a966-7fdfd3f8f04f

Introduction

The field of augmented reality (AR) is rapidly growing with many new potential applications in medical education. This systematic review investigated the current state of augmented reality applications (ARAs) and developed an analytical model to guide future research in assessing ARAs as teaching tools in medical education.

Methods

A literature search was conducted using PubMed, Embase, Web of Science, Cochrane Library, and Google Scholar. This review followed PRISMA guidelines and included publications from January 1, 2000 to June 18, 2018. Inclusion criteria were experimental studies evaluating ARAs implemented in healthcare education published in English. Our review evaluated study quality and determined whether studies assessed ARA validity using criteria established by the GRADE Working Group and Gallagher et al., respectively. These findings were used to formulate an analytical model to assess the readiness of ARAs for implementation in medical education.

Results

We identified 100,807 articles in the initial literature search; 36 met inclusion criteria for final review and were categorized into three categories: Surgery (23), Anatomy (9), and Other (4). The overall quality of the studies was poor and no ARA was tested for all five stages of validity. Our analytical model evaluates the importance of research quality, application content, outcomes, and feasibility of an ARA to gauge its readiness for implementation.

Conclusion

While AR technology is growing at a rapid rate, the current quality and breadth of AR research in medical training is insufficient to recommend the adoption into educational curricula. We hope our analytical model will help standardize AR assessment methods and define the role of AR technology in medical education.

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<![CDATA[Maintenance of certification for practicing physicians: a review of current challenges and considerations]]> https://www.researchpad.co/article/Nf6092ce1-c38f-43f5-813f-4652f4785c18

Maintenance of certification (MOC) has become increasingly important in medicine to ensure maintenance of competence throughout a physician’s career. This paper reviews current issues and challenges associated with MOC in medicine, including how to define medical competencies for practicing physicians, assessment, and how best to support physicians’ lifelong learning in a continuous and self-motivated way. We explore how the combination of self-monitoring, regular feedback, and peer support could improve self-assessment. Effective MOC programs are learner-driven, focused on every day practice, and incorporate educational principles. We discuss the importance of MOC to the physicians’ actual practice to improve acceptability. We review the benefits of tailored programs as well as decentralization of MOC programs to better characterize the physician’s practice. Lastly, we discuss the value of simulation-based medical education in MOC programs. Simulation-based education could be used to practice uncommon complications, life-threatening scenarios, non-technical skills improvement, and become proficient with new technology. As learners find simulation experiences educationally valuable, clinically relevant, and positive, simulation could be a way of increasing physicians’ participation in MOC programs.

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<![CDATA[Photoacoustic elastography imaging: a review]]> https://www.researchpad.co/article/N06a3bfc2-4803-455e-9312-c01601ab25a8

Abstract.

Elastography imaging is a promising tool—in both research and clinical settings—for diagnosis, staging, and therapeutic treatments of various life-threatening diseases (including brain tumors, breast cancers, prostate cancers, and Alzheimer’s disease). Large variation in the physical (elastic) properties of tissue, from normal to diseased stages, enables highly sensitive characterization of pathophysiological states of the diseases. On the other hand, over the last decade or so, photoacoustic (PA) imaging—an imaging modality that combines the advantageous features of two separate imaging modalities, i.e., high spatial resolution and high contrast obtainable, respectively, from ultrasound- and optical-based modalities—has been emerging and widely studied. Recently, recovery of elastic properties of soft biological tissues—in addition to prior reported recovery of vital tissue physiological information (Hb, HbO2, SO, and total Hb), noninvasively and nondestructively, with unprecedented spatial resolution (μm) at penetration depth (cm)—has been reported. Studies demonstrating that combined recovery of mechanical tissue properties and physiological information—by a single (PA) imaging unit—pave a promising platform in clinical diagnosis and therapeutic treatments. We offer a comprehensive review of PA imaging technology, focusing on recent advances in relation to elastography. Our review draws out technological challenges pertaining to PA elastography (PAE) imaging, and viable approaches. Currently, PAE imaging is in the nurture stage of its development, where the technology is limited to qualitative study. The prevailing challenges (specifically, quantitative measurements) may be addressed in a similar way by which ultrasound elastography and optical coherence elastography were accredited for quantitative measurements.

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<![CDATA[Photoacoustic imaging in the second near-infrared window: a review]]> https://www.researchpad.co/article/Neb8fa685-d431-45a6-84cf-91591070e8a7

Abstract.

Photoacoustic (PA) imaging is an emerging medical imaging modality that combines optical excitation and ultrasound detection. Because ultrasound scatters much less than light in biological tissues, PA generates high-resolution images at centimeters depth. In recent years, wavelengths in the second near-infrared (NIR-II) window (1000 to 1700 nm) have been increasingly explored due to its potential for preclinical and clinical applications. In contrast to the conventional PA imaging in the visible (400 to 700 nm) and the first NIR-I (700 to 1000 nm) window, PA imaging in the NIR-II window offers numerous advantages, including high spatial resolution, deeper penetration depth, reduced optical absorption, and tissue scattering. Moreover, the second window allows a fivefold higher light excitation energy density compared to the visible window for enhancing the imaging depth significantly. We highlight the importance of the second window for PA imaging and discuss the various NIR-II PA imaging systems and contrast agents with strong absorption in the NIR-II spectral region. Numerous applications of NIR-II PA imaging, including whole-body animal imaging and human imaging, are also discussed.

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<![CDATA[Review of methods and applications of attenuation coefficient measurements with optical coherence tomography]]> https://www.researchpad.co/article/N4307a5a9-a32e-4ecd-9ef4-1dd94654596d

Abstract.

The optical attenuation coefficient (AC), an important tissue parameter that measures how quickly incident light is attenuated when passing through a medium, has been shown to enable quantitative analysis of tissue properties from optical coherence tomography (OCT) signals. Successful extraction of this parameter would facilitate tissue differentiation and enhance the diagnostic value of OCT. In this review, we discuss the physical and mathematical basis of AC extraction from OCT data, including current approaches used in modeling light scattering in tissue and in AC estimation. We also report on demonstrated clinical applications of the AC, such as for atherosclerotic tissue characterization, malignant lesion detection, and brain injury visualization. With current studies showing AC analysis as a promising technique, further efforts in the development of methods to accurately extract the AC and to explore its potential use for more extensive clinical applications are desired.

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<![CDATA[Optical elastography and tissue biomechanics]]> https://www.researchpad.co/article/Na0977693-0895-445d-982b-f935e48e57f4

Abstract.

Mechanical forces play an important role in the behavior and development of biological systems and disease at all spatial scales, from cells and their constituents to tissues and organs. Such forces have a profound influence on the health, structural integrity, and normal function of cells and organs. Accurate knowledge of cell and tissue biomechanical properties is essential to map the distribution of forces and mechanical cues in biological systems. Cell and tissue biomechanical properties are also known to be important on their own as indicators of health or disease states. Hence, optical elastography and biomechanics methods can aid in the understanding and clinical diagnosis of a wide variety of diseases. We provide a brief overview and highlight of the Optical Elastography and Tissue Biomechanics VI conference, which took place in San Francisco, February 2 and 3, 2019, as a part of Photonics West symposium.

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<![CDATA[Clinical applications of laser speckle contrast imaging: a review]]> https://www.researchpad.co/article/Nebb00f9c-a06e-4358-b195-62ff035b59b8

Abstract.

When a biological tissue is illuminated with coherent light, an interference pattern will be formed at the detector, the so-called speckle pattern. Laser speckle contrast imaging (LSCI) is a technique based on the dynamic change in this backscattered light as a result of interaction with red blood cells. It can be used to visualize perfusion in various tissues and, even though this technique has been extensively described in the literature, the actual clinical implementation lags behind. We provide an overview of LSCI as a tool to image tissue perfusion. We present a brief introduction to the theory, review clinical studies from various medical fields, and discuss current limitations impeding clinical acceptance.

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<![CDATA[Optical phantoms for biomedical polarimetry: a review]]> https://www.researchpad.co/article/N9514d54f-1226-44bb-aa92-c939b195a792

Abstract.

Calibration, quantification, and standardization of the polarimetric instrumentation, as well as interpretation and understanding of the obtained data, require the development and use of well-calibrated phantoms and standards. We reviewed the status of tissue phantoms for a variety of applications in polarimetry; more than 500 papers are considered. We divided the phantoms into five groups according to their origin (biological/nonbiological) and fundamental polarimetric properties of retardation, depolarization, and diattenuation. We found that, while biological media are generally depolarizing, retarding, and diattenuating, only one of all the phantoms reviewed incorporated all these properties, and few considered at least combined retardation and depolarization. Samples derived from biological tissue, such as tendon and muscle, remain extremely popular to quickly ascertain a polarimetric system, but do not provide quantifiable results aside from relative direction of their principal optical axis. Microspheres suspensions are the most utilized phantoms for depolarization, and combined with theoretical models can offer true quantification of depolarization or degree of polarization. There is a real paucity of birefringent phantoms despite the retardance being one of the most interesting parameters measurable with polarization techniques. Therefore, future work should be directed at generating truly reliable and repeatable phantoms for this metric determination. Diattenuating phantoms are rare and application-specific. Given that diattenuation is considered to be low in most biological tissues, the lack of such phantoms is seen as less problematic. The heterogeneity of the phantoms reviewed points to a critical need for standardization in this field. Ultimately, all research groups involved in polarimetric studies and instruments development would benefit from sharing a limited set of standardized polarimetric phantoms, as is done earlier in the round robin investigations in ellipsometry.

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<![CDATA[Review of the state of the art in cardiovascular endoscopy imaging of atherosclerosis using photoacoustic techniques with pulsed and continuous-wave optical excitations]]> https://www.researchpad.co/article/Na489025f-ba96-4f65-b739-1e9778b2daaf

Abstract.

Intravascular photoacoustics (IV-PA) is an emerging atherosclerosis imaging modality that provides chemical-specific optical information of arterial walls with acoustic depth penetration and resolution. As lipid composition of atherosclerotic plaques is considered to be one of the primary indicators for plaque vulnerability, many IV-PA applications are calibrated so as to target plaque necrotic cores. Based on the mode of optical excitation and the corresponding signal processing technique, IV-PA is categorized into two different modalities. The pulse-based IV-PA has been the universal IV-PA imaging mode with its high peak power and straightforward time-domain signal processing technique. As an alternative, the low power continuous-wave (CW)-based IV-PA has been under intense development as a radar-like frequency-domain signal processing modality. The two state-of-the-art types of IV-PA are reviewed in terms of their physics and imaging capabilities, with major emphasis on frequency-swept CW-based IV-PA that has been recently introduced in the field.

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<![CDATA[The Role of Proinflammatory Cytokine Interleukin-18 in Radiation Injury]]> https://www.researchpad.co/article/5b015f60463d7e46c14c5cc8

Abstract

Massive radiation-induced inflammatory factors released from injured cells may cause innate and acquired immune reactions that can further result in stress response signal activity-induced local and systemic damage. IL‐1 family members IL‐1β, IL‐18, and IL‐33 play key roles in inflammatory and immune responses and have been recognized to have significant influences on the pathogenesis of diseases. IL‐1β, IL‐18, and IL‐33 share similarities of cytokine biology, but differences exist in signaling pathways. A key component of the inflammatory reaction is the inflammasome, which is a caspase‐1‐containing multiprotein oligomer. Pathological stimuli such as radiation can induce inflammasome and caspase‐1 activation, and subsequently cause maturation (activation) of pro-forms of IL‐1 and IL‐18 upon caspase‐1 cleavage. This caspase‐1 dependent and IL‐1 and IL‐18 associated cell damage is defined as pyroptosis. Activated IL‐1 and IL‐18 as proinflammatory cytokines drive pathology at different immune and inflammatory disorders through Toll-like receptor (TLR) signaling. While the mechanisms of IL‐1β-induced pathophysiology of diseases have been well studied, IL‐18 has received less attention. The author recently reported that gamma radiation highly increased IL‐1β, IL‐18 and IL‐33 expression in mouse thymus, spleen and/or bone marrow cells; also circulating IL‐18 can be used as a radiation biomarker to track radiation injury in mice, minipigs, and nonhuman primates. This mini-review focuses on the role of IL‐18 in response to gamma radiation-induced injury.

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