bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effect of Climate on the Outbreak of Covid-19: A Review
Authors: Kirana Candra , Samsul  , Hapsir Hesty Yariska , Nurmalita Fitria , Tosepu Ramadhan
Published: May 2021

COVID-19 causes various kinds of life problems, including the occurrence of a global health crisis, social, psychological problems, and a prolonged economic crisis. Climate-related dynamics have an impact on patterns of human health and disease. This study aimed to investigate the effect of climate on the outbreak of COVID-19. This study used a literature review approach on research on climate and Covid-19, using the Google Scholar, Scienceirect. The article taken was original research in the recent year. It was found that the effect of climate change had a significant relation to the increase in Covid-19 cases. Therefore, it can be concluded that climate is a risk factor for increasing the outbreak of the Covid-19 Virus. However, one previous study predicted that with a mathematical model that included human demographic conditions and mobility, it was concluded that a tropical climate could help inhibit the oubreak of the virus because tropical climatic condition could make the virus more volatile.
Transportability From Randomized Trials to Clinical Care: On Initial HIV Treatment With Efavirenz and Suicidal Thoughts or Behaviors
Authors: Mollan Katie R , Pence Brian W , Xu Steven , Edwards Jessie K , Mathews W Christopher , O’Cleirigh Conall , Crane Heidi M , Eaton Ellen F , Collier Ann C , Weideman Ann Marie K , Westreich Daniel , Cole Stephen R , Tierney Camlin , Bengtson Angela M ,   for the CFAR Network of Integrated Clinical Systems and the AIDS Clinical Trials Group
Published: May 2021

In an analysis of randomized trials, use of efavirenz for treatment of human immunodeficiency virus (HIV) infection was associated with increased suicidal thoughts/behaviors. However, analyses of observational data have found no evidence of increased risk. To assess whether population differences might explain this divergence, we transported the effect of efavirenz use from these trials to a specific target population. Using inverse odds weights and multiple imputation, we transported the effect of efavirenz on suicidal thoughts/behaviors in these randomized trials (participants were enrolled in 2001–2007) to a trials-eligible cohort of US adults initiating antiretroviral therapy while receiving HIV clinical care at medical centers between 1999 and 2015. Overall, 8,291 cohort participants and 3,949 trial participants were eligible. Prescription of antidepressants (19% vs. 13%) and injection drug history (16% vs. 10%) were more frequent in the cohort than in the trial participants. Compared with the effect in trials, the estimated hazard ratio for efavirenz on suicidal thoughts/behaviors was attenuated in our target population (trials: hazard ratio (HR) = 2.3 (95% confidence interval (CI): 1.2, 4.4); transported: HR = 1.8 (95% CI: 0.9, 4.4)), whereas the incidence rate difference was similar (trials: HR = 5.1 (95% CI: 1.6, 8.7); transported: HR = 5.4 (95% CI: −0.4, 11.4)). In our target population, there was greater than 20% attenuation of the hazard ratio estimate as compared with the trials-only estimate. Transporting results from trials to a target population is informative for addressing external validity.
Black bear colour polymorphism through a fragmented Snell’s window
Authors: Reimchen Thomas E , Hunter Danial , Eggenberger Jakob H
Published: May 2021

The white colour morph of the black bear (Ursus americanus kermodei) occurring on islands on the coast of British Columbia, western Canada, captures more salmon (Oncorhynchus spp.) than does the black morph and is hypothesized to have reduced contrast against the sky from the visual perspective of the salmon. We tested this hypothesis in a natural salmon stream by recording the number and proximity of chum salmon (Oncorhynchus keta) approaches (N = 1617 fish, 91 trials) towards life-size bear models differing in body and leg coloration under a mixed forest-sky canopy. Although salmon approached the white models at a much higher rate than black models, consistent with camouflage, we found greater abrupt evasions to the black models, largely independent of their contrast against the above-surface or below-surface backgrounds. Upward-facing sub-surface video-imaging through the rippled water-air interface indicated major visual fragmentation of the model’s integrity. We suggest that increased evasiveness to black models reflects an evolutionary response due to 3+ million years of trophic interaction between salmon and bears, and that the major differences between calm vs. rippled conditions through the optical cone (Snell’s window) at the water-air interface remains a largely unexplored theme in assessing foraging preferences and adaptive coloration within and among species using the water-air interface.
Troponin measurement for risk stratification after cytoreductive surgery
Authors: Vacheron C.-H. , Lambert A. , Fauvernier M. , Vassal O. , Wallet F. , Bakrin N. , Vaudoyer D. , Kepenekian V. , Passot G. , Glehen O. , Piriou V. , Friggeri A.
Published: May 2021

Several studies have raised interest in the use of postoperative troponin levels to stratify risk of postoperative morbidity and mortality. In this study, postoperative troponin concentration after cytoreductive surgery (with or without hyperthermic intraoperative intraperitoneal chemotherapy) was associated with severe postoperative complications, and enhanced the predictive capability of a multivariable model focusing on postoperative complications.
‘Out of the Frying Pan into the Fire’: Mauritian Social Workers’ Perspectives on Disaster Governance in Mauritius
Authors: Rambaree Komalsingh , Rambaree Brita Backlund
Published: May 2021

Mauritius, which is a Small Island Developing State with low economic resilience and limited capacity to deal with disasters, is currently trying to recover from two major disasters—COVID-19 and an oil spill caused by a shipwreck. This article aims to explore the Mauritian social workers’ perspectives on the disaster governance in relation to these double disasters. Data were collected from eighteen social workers using web-based/ online interview tools in September 2020. An abductive thematic network method based on governance network theory was used to analyse the collected data with the help of the ATLAS.ti software. In the findings, the perspectives of the respondents on the structures and mechanisms for disaster social work and the factors that affect disaster governance in Mauritius are presented and discussed. This article concludes that there is a lack of organised structures and mechanisms for disaster social work, and there is a need to promote good governance in disaster response in Mauritius.
To Shield or Not to Shield? There Should Be No Question—Black African Social Workers Experiences during COVID-19 in England
Authors: Tedam Prospera
Published: May 2021

Using three tenets of Critical Race Theory as the analytical lens, namely, counter story-telling, everyday racism and whiteness as privilege, this qualitative study examined the experiences of twenty Black African social workers during the Coronavirus disease (Covid-19) pandemic in England. The findings suggest that there was a different and often less favourable application of the rules and policies for Black African social workers in relation to COVID-19 and in comparison to their White peers. In addition, Black African social workers expressed frustration about the inadequacy of risk assessments undertaken to gauge the level of risk posed by continuous engagement with service users. A strong recommendation for culturally responsive leadership is made alongside the need for managers, supervisors and employers to become allies to their staff from Black and other minority ethnic backgrounds.
PD-1 blockade prevents the progression of oral carcinogenesis
Authors: Dong Yunmei , Wang Zhen , Mao Fei , Cai Luyao , Dan Hongxia , Jiang Lu , Zeng Xin , Li Taiwen , Zhou Yu , Chen Qianming
Published: May 2021

Oral squamous cell carcinoma (OSCC) is one of the most common malignancies in the head and neck with a poor prognosis. Oral cancer development is a multistep process involving carcinogenesis. Though significant advances in cancer immunotherapy over the years, there is lack of evidence for T-cell exhaustion during oral carcinogenesis. Clinical specimens from healthy donors and patients diagnosed with oral leukoplakia (OLK) or OSCC were collected for immunohistochemical staining with PD-L1, CD86, CD8, PD-1 and CTLA-4 antibodies. Meanwhile, chemically induced mouse models of oral carcinogenesis were constructed with 4-nitroquinolone-N-oxide induction. Exhaustion status of T cells was measured by flow cytometry for spleens and by multiplex immunohistochemistry for formalin-fixed paraffin-embedded lesions in multiple stages of oral carcinogenesis. The efficacy of PD-1 blockade with or without cisplatin treatment was evaluated on the mice in precancerous and OSCC stages. We observed higher expression of PD-1 in the human OLK and OSCC tissues compared with the normal, while low expression CTLA-4 in all oral mucosa tissues. Animal experiments showed that the exhausted CD4+ T cells existed much earlier than exhausted CD8+ T cells, and an increased ratio of stem-like exhausted T cells and partially exhausted T cells were detected in the experimental groups. Besides, the expression of immune checkpoint markers (PDCD1, CTLA4 and HAVCR2) was strongly positively correlated with cytokines (IFNG and IL-2). In summary, T-cell exhaustion plays a vital role in oral carcinogenesis, and PD-1 blockade can prevent the progression of oral carcinogenesis.
Sympathovagal imbalance decades after atrial septal defect repair: a long-term follow-up study
Authors: Alstrup Mathias , Karunanithi Zarmiga , Maagaard Marie Ø , Poulsen Steen H , Hjortdal Vibeke E
Published: May 2021

OBJECTIVES

Recent evidence suggests that patients with a corrected atrial septal defect (ASD) have higher morbidity and mortality. An abnormal autonomic regulation of the heart may be a part of the explanation for this. Our objective was to study heart rate variability (HRV) in adults with a corrected ASD as a prominent tool to investigate the autonomic regulation of the heart.

METHODS

Autonomic cardiac function was investigated in adults with either a surgically closed or percutaneously closed ASD and healthy control subjects. A 48-h Holter monitor was performed on each participant and HRV was assessed.

RESULTS

A total of 17 patients with surgically closed ASDs, 18 percutaneously closed ASDs and 18 controls were included. The mean age in the surgical group, percutaneous group and controls was 32 ± 9, 28 ± 7 and 32 ± 10 years, respectively. The mean time since closure was 19 ± 8 years for the surgical group and 15 ± 5 years for the percutaneous group. The surgically closed ASD patients showed decreased HRV in all six parameters studied when compared to the controls. Similarly, the percutaneously closed ASDs showed decreased HRV in three out of six parameters when compared to controls.

CONCLUSIONS

Adults with an ASD, whether closed surgically or percutaneously, have impaired HRV compared to their age- and sex-matched controls, more so in the patients with a surgically closed ASD.

Clinical trial registration number

ClinicalTrials.gov (identifier: NCT03565471).
Real-time intracardiac echocardiography validation of saline-enhanced radiofrequency needle-tip ablation: lesion characteristics and gross pathology correlation
Authors: Dickow Jannis , Wang Songyun , Suzuki Atsushi , Imamura Kimitake , Lehmann H Immo , Parker Kay D , Newman Laura K , Monahan Kristi H , Rettmann Maryam E , Curley Michael G , Packer Douglas L
Published: May 2021

Aims

With the implementation of saline-enhanced radiofrequency (SERF) needle-tip ablation, real-time validation of lesion formation is needed for the controllable creation of transmural lesions. The aim of the study was to analyse the ability of two-dimensional intracardiac echocardiography (2D-ICE) to guide and validate SERF ablation in real-time.

Methods and results

Fifty-six SERF energy deliveries at left ventricular sites of 11 dogs guided by 2D-ICE were analysed (power: 15–50 W; time: 25–120 s; irrigation saline: 60°C with 10 mL/min flow rate). Catheter tip/tissue orientation and lesion formation could be well detected by 2D-ICE in 49 (87.5%) energy deliveries. Gross pathology analysis confirmed excellent 2D-ICE lesion localization, the ability to detect transmural lesions (70% sensitivity, 47% specificity) and positive correlation between 2D-ICE and the corresponding gross pathology measurements of ‘maximal lesion depth’; (repeated measures correlation: rrm = 0.43, P = 0.012) and ‘depth at maximal lesion width’ (D@MW; rrm = 0.51, P = 0.003). The median angle between SERF catheter tip and endocardium was 76° [interquartile range (IQR) 58–83°]. The more perpendicular the catheter tip/tissue orientation was the deeper D@MW (rrm = 0.32, P = 0.045). Grade 3 microbubbles on 2D-ICE during ablation, indicating inadequate catheter tip/tissue contact, was associated with smaller lesion volumes than with Grade 1 microbubbles (284.8 mm3 [IQR 151.3–343.1] vs. 2114.1 mm3 [IQR 1437.0–3026.3], P < 0.001).

Conclusion

With excellent lesion localization and a 70% detection rate of transmural lesions, 2D-ICE is well suited to validate SERF ablation lesion formation in real-time. The catheter tip/tissue angle impacts the lesion formation and through perpendicular catheter positioning, deeper intramural areas of the myocardium can be reached.
The β-angle can help guide clinical decisions in the diagnostic work-up of patients suspected of Brugada syndrome: a validation study of the β-angle in determining the outcome of a sodium channel provocation test
Authors: van der Ree Martijn H , Vendrik Jeroen , Verstraelen Tom E , Kors Jan A , Amin Ahmad S , Wilde Arthur A M , Tan Hanno L , Postema Pieter G
Published: May 2021

Aims

In patients with Brugada syndrome (BrS) but without spontaneous Type-1 electrocardiogram, several electrocardiographic characteristics have been studied, including the β-angle. Previous studies suggested that the β-angle might be useful in distinguishing BrS-patients from patients with only suggestive repolarization patterns without performing sodium channel blocker provocation testing. In this study, we aimed to determine the diagnostic value of the β-angle in patients suspected of BrS.

Methods and results

A large cohort (n = 1430) of consecutive patients who underwent provocation testing was evaluated. β-angles were measured in leads V1, V2, and their corresponding positions over the second and third intercostal space. Receiver-operating characteristic curves were constructed and the diagnostic accuracy of previously reported β-angle cut-offs were calculated and evaluated. The importance of the β-angle for predicting the provocation test outcome was determined using a prediction model constructed with logistic regression. The optimum β-angle cut-off in our cohort for ruling out a positive provocation test was 15°; sensitivities were 80–98% and negative predictive values were 79–96% among the right precordial leads. Previously reported β-angle cut-offs performed less well, indicated by lower Youden indices. In the optimism-corrected prediction model [C-statistic: 0.78 (95% CI: 0.75–0.81)], the β-angle had large value (Z-score: 2.1–10.3) and aided construction of a nomogram to predict test outcome.

Conclusion

To predict the outcome of provocation testing for BrS, the β-angle alone does not demonstrate strong diagnostic characteristics. However, the β-angle is an important variable to predict provocation test outcome and thus has added value.
Functional trait relationships demonstrate life strategies in terrestrial prokaryotes
Authors: Finn Damien R , Bergk-Pinto Benoît , Hazard Christina , Nicol Graeme W , Tebbe Christoph C , Vogel Timothy M
Published: May 2021

Functional, physiological traits are the underlying drivers of niche differentiation. A common framework related to niches occupied by terrestrial prokaryotes is based on copiotrophy or oligotrophy, where resource investment is primarily in either rapid growth or stress tolerance, respectively. A quantitative trait-based approach sought relationships between taxa, traits and niche in terrestrial prokaryotes. With 175 taxa from 11 Phyla and 35 Families (n = 5 per Family), traits were considered as discrete counts of shared genome-encoded proteins. Trait composition strongly supported non-random functional distributions as preferential clustering of related taxa via unweighted pair-group method with arithmetic mean. Trait similarity between taxa increased as taxonomic rank decreased. A suite of Random Forest models identified traits significantly enriched or depleted in taxonomic groups. These traits conveyed functions related to rapid growth, nutrient acquisition and stress tolerance consistent with their presence in copiotroph-oligotroph niches. Hierarchical clustering of traits identified a clade of competitive, copiotrophic Families resilient to oxidative stress versus glycosyltransferase-enriched oligotrophic Families resistant to antimicrobials and environmental stress. However, the formation of five clades suggested a more nuanced view to describe niche differentiation in terrestrial systems is necessary. We suggest considering traits involved in both resource investment and acquisition when predicting niche.
Gravity anomaly models with geophysical interpretation of the Republic of Croatia, including Adriatic and Dinarides regions
Authors: Varga M , Stipčević J
Published: May 2021

Models of gravity corrections and anomalies are created and distributed over the territory of the Republic of Croatia, including the Adriatic and Dinarides regions. Published models cover the study area between 42.0°N < φ < 46.6°N and 13.0°E < λ < 19.5°E with a 1′ × 1′ resolution. Distributed models include gravity corrections and anomalies of normal gravity, atmosphere, free air, Bouguer, terrain, complete Bouguer and topographic–isostatic according to the Airy–Heiskanen model. A high-resolution digital elevation/bathymetry model was prepared from SRTMv3.0 and GEBCO2019 models. It was then used for the computation of topographic and topographic–isostatic gravity effects using rectangular prisms with constant crustal density. Gridding of the scattered gravity data was performed with the Kriging interpolation method using complete Bouguer anomalies by implementing the remove–grid–restore methodology. Developed models were interpreted providing insights into the topography-reduced (anomalous) Earth’s gravity field reflecting the variations in mass/density distribution within the crust and upper mantle over the study area.
Plasticity of the human preimplantation embryo: developmental dogmas, variations on themes and self-correction
Authors: Coticchio Giovanni , Barrie Amy , Lagalla Cristina , Borini Andrea , Fishel Simon , Griffin Darren , Campbell Alison
Published: May 2021

BACKGROUND

IVF for the treatment of infertility offers unique opportunities to observe human preimplantation development. Progress in time-lapse technology (TLT) and preimplantation genetic testing (PGT) has greatly expanded our knowledge of developmental patterns leading to a healthy pregnancy or developmental failure. These technologies have also revealed unsuspected plastic properties of the preimplantation embryo, at macromolecular, cellular and multicellular levels.

OBJECTIVE AND RATIONALE

This review focuses on the emerging concept of plasticity of the human embryo as revealed by recent evidence derived from TLT and PGT, calling for an updated and more precise redefinition of the boundaries between normal and abnormal development.

SEARCH METHODS

PubMed was used to search the MEDLINE database for peer-reviewed English-language original articles and reviews concerning human preimplantation development. Cross-searches were performed by adopting ‘fertilisation‘, ‘pronucleus’, ‘cleavage’, ‘multinucleation’, ‘compaction’, ‘embryo’, ‘preimplantation genetic testing’, ‘aneuploidy’, mosaicism’, ‘micromanipulation’, ‘time-lapse microscopy’ and ‘IVF/assisted reproduction’ as main terms. The most relevant publications, i.e. those concerning major phenomena occurring during normal and abnormal development—with a focus on the human species—were assessed and discussed critically.

OUTCOMES

Advances in TLT and PGT have revealed an astonishing plasticity and self-correction ability of the human preimplantation embryo in vitro. At fertilisation, an abnormal number of pronuclei do not always result in the formation of an aneuploid blastocyst. Animal studies and preliminary human observations indicate that combining of parental genomes may occur at the early cleavage stage, if not at fertilisation. Multinucleation occurs with much higher prevalence than previously thought and may be corrected at later cleavage stages. Irregular cleavage (multichotomous, direct, rapid and reverse cleavages) can generate chromosome segregation abnormalities that often lead to developmental arrest, but that sporadically may be confined to cells excluded from the blastocyst, and may sometimes result in viable pregnancy. Mitotic errors can generate mosaic blastocysts, but alternatively normal embryos may form from selective death or clonal depletion of aneuploid cells.

WIDER IMPLICATIONS

Deviations from developmental dogmas and the increasing evidence of plasticity of the human embryo challenge current embryological notions and suggest the need to write new rules governing cell cycle, cell determination and chromosome segregation during preimplantation development.
Hypertoric Hitchin Systems and Kirchhoff Polynomials
Authors: Groechenig Michael , McBreen Michael
Published: May 2021

We define a formal algebraic analogue of hypertoric Hitchin systems, whose complex-analytic counterparts were defined by Hausel–Proudfoot. These are algebraic completely integrable systems associated to a graph $\Gamma $. We study the variation of the Tamagawa number of the resulting family of abelian varieties and show that it is described by the Kirchhoff polynomial of the graph $\Gamma $. In particular, this allows us to compute their $p$-adic volumes. We conclude the article by remarking that these spaces admit a volume preserving tropicalisation.
Odd-Dimensional GKM-Manifolds of Non-Negative Curvature
Authors: Escher Christine , Goertsches Oliver , Searle Catherine
Published: May 2021

Let $M$ be a closed, odd GKM$_3$ manifold of non-negative sectional curvature. We show that in this situation one can associate an ordinary abstract GKM$_3$ graph to $M$ and prove that if this graph is orientable, then both the equivariant and the ordinary rational cohomology of $M$ split off the cohomology of an odd-dimensional sphere.
Metrics and Isometries for Convex Functions
Authors: Li Ben , Mussnig Fabian
Published: May 2021

We introduce a class of functional analogs of the symmetric difference metric on the space of coercive convex functions on ${\mathbb{R}}^n$ with full-dimensional domain. We show that convergence with respect to these metrics is equivalent to epi-convergence. For a large class of these natural metrics, we are able to provide a full classification of all isometries. In addition, we introduce new functional analogs of the Hausdorff metric on the spaces of coercive convex functions and super-coercive convex functions, respectively, and prove equivalence to epi-convergence.
Sticky apps, not sticky hands: A systematic review and content synthesis of hand hygiene mobile apps
Authors: Gasteiger Norina , Dowding Dawn , Ali Syed Mustafa , Scott Ashley Jordan Stephen , Wilson Paul , van der Veer Sabine N
Published: May 2021

Objective

The study sought to identify smartphone apps that support hand hygiene practice and to assess their content, technical and functional features, and quality. A secondary objective was to make design and research recommendations for future apps.

Materials and Methods

We searched the UK Google Play and Apple App stores for hand hygiene smartphone apps aimed at adults. Information regarding content, technical and functional features was extracted and summarized. Two raters evaluated each app, using the IMS Institute for Healthcare Informatics functionality score and the Mobile App Rating Scale (MARS).

Results

A total of 668 apps were identified, with 90 meeting the inclusion criteria. Most (96%) were free to download. The majority (78%) intended to educate or inform or remind users to hand wash (69%), using behavior change techniques such as personalization and prompting practice. Only 20% and 4% named a best practice guideline or had expert involvement in development, respectively. Innovative means of engagement were used in 42% (eg, virtual or augmented reality or geolocation-based reminders). Apps included an average of 2.4 out of 10 of the IMS functionality criteria (range, 0-8). The mean MARS score was 3.2 ± 0.5 out of 5, and 68% had a minimum acceptability score of 3. Two had been tested or trialed.

Conclusions

Although many hand hygiene apps exist, few provide content on best practice. Many did not meet the minimum acceptability criterion for quality or were formally trialed or tested. Research should assess the feasibility and effectiveness of hand hygiene apps (especially within healthcare settings), including when and how they “work.” We recommend that future apps to support hand hygiene practice are developed with infection prevention and control experts and align with best practice. Robust research is needed to determine which innovative methods of engagement create “sticky” apps.
β-Caryophyllene attenuates lipopolysaccharide-induced acute lung injury via inhibition of the MAPK signalling pathway
Authors: Zhang Yong , Zhang Haibo , Li Yan , Wang Muqun , Qian Feng
Published: May 2021

Objectives

Acute lung injury (ALI) is a pulmonary manifestation of an acute systemic inflammatory response, which is associated with high morbidity and mortality. Accordingly, from the perspective of treating ALI, it is important to identify effective agents and elucidate the underlying modulatory mechanisms. β-Caryophyllene (BCP) is a naturally occurring bicyclic sesquiterpene that has anti-cancer and anti-inflammatory activities. However, the effects of BCP on ALI have yet to be ascertained.

Methods

ALI was induced intratracheally, injected with 5 mg/kg LPS and treated with BCP. The bone marrow-derived macrophages (BMDMs) were obtained and cultured then challenged with 100 ng/ml LPS for 4 h, with or without BCP pre-treatment for 30 min.

Key findings

BCP significantly ameliorates LPS-induced mouse ALI, which is related to an alleviation of neutrophil infiltration and reduction in cytokine production. In vitro, BCP was found to reduce the expression of interleukin-6, interleukin-1β and tumour necrosis factor-α, and suppresses the MAPK signalling pathway in BMDMs, which is associated with the inhibition of TAK1 phosphorylation and an enhancement of MKP-1 expression.

Conclusions

Our data indicate that BCP protects against inflammatory responses and is a potential therapeutic agent for the treatment of LPS-induced acute lung injury.
Electricity Running Down the Arm
Authors: Molinari William J.
Published: May 2021

Radiating pain involving the upper extremities requires careful consideration of a wide range of differential diagnoses. Paramount among them are cervical myelopathy, cervical radiculopathy, and idiopathic brachial neuropathy. Timely diagnosis of these conditions, correlating a patient’s symptoms and physical examination findings with abnormalities identified on advanced imaging studies and results of electromyography and nerve conduction studies, guides proper conservative treatment and surgical intervention, if warranted. The clinician must always maintain a healthy index of suspicion for these conditions when evaluating a patient presenting with pain and other neurological complaints of the upper extremities. This chapter presents the basics of evaluating cervical spondylotic myelopathy, differentiating it from other cervical conditions. It also provides the basis for its stepwise management options.
A “Golf Ball” in the Elbow
Authors: Mahajer Amir , Cicone Caitlin M. , Guanche Melissa
Published: May 2021

Pain, warmth, erythema, and edema about the elbow joint require in-depth clinical and diagnostic evaluation. Septic arthritis/bursitis, malignancy, and fractures must be considered and ruled out. Olecranon bursitis is an inflammatory condition affecting the superficial bursa of the posterior elbow. It is often caused by trauma, compression, overuse, inflammatory arthritis, crystal deposition, and/or infection. It may be difficult to differentiate clinically between an inflamed bursa and an infection. Aspiration, fluid analysis, and serum studies may be necessary. In addition, two pathologies may coexist, such as gout and infection. In septic bursitis, the most common pathogen is Staphylococcus aureus. Gout is a crystal-induced arthropathy that may affect joints or bursae. The primary risk factor in gout is hyperuricemia, which is best diagnosed by the polarizing light microscopy finding of negatively birefringent crystals.
Thumb Pain That Keeps Getting Worse
Authors: Martinez-Silvestrini Julio A.
Published: May 2021

Pain at the base of the thumb is a common cause of hand pain. Two of the most common causes of thumb pain are de Quervain’s tenosynovitis and carpometacarpal osteoarthritis. De Quervain’s tenosynovitis is a tendinosis of the abductor pollicis longus and extensor pollicis brevis, localized over the radial aspect of the wrist. De Quervain’s tenosynovitis is commonly diagnosed with physical examination and does not require imaging studies. Although physical examination is helpful to identify patients with carpometacarpal osteoarthritis, the definite diagnosis requires imaging. For both diagnoses, the initial treatment is conservative, consisting of bracing, rehabilitation, and, sometimes, injections. In cases that fail conservative management, surgical options may be indicated.
A Locking Ring Finger
Authors: Cuevas-Trisan Ramon
Published: May 2021

Trigger finger is one of the most common adult hand painful conditions. It may cause a finger flexion “contracture” that is dynamic and corrected as opposed to that seen in Dupuytren’s disease which causes a true flexion contracture that cannot be manually corrected. Conditions to consider in a diabetic patient with finger flexion contractures include trigger finger, Dupuytren’s disease, and diabetic cheiroarthropathy. Trigger fingers and Dupuytren contractures tend to be more isolated and localized, in contrast to diabetic chieroarthropathy, which causes more generalized finger contractures. Appropriate diagnosis leads to adequate management. Conservative care tends to be beneficial for trigger finger but less so for Dupuytren’s disease. Both conditions may require invasive and surgical management for correction.
Intrapartum Monitoring and Fetal Assessment
Authors: Rhoades Courtney , Vanderhoef Kristen
Published: May 2021

This chapter provides an overview of standard fetal monitoring during labor and delivery, how to choose between and interpret current monitoring modalities, and proper resuscitative measures to initiate for a fetus demonstrating compromise. This chapter starts with current fetal monitoring techniques, including the associated strengths, weaknesses, and risks, then goes through interpretation of fetal heart rate strips, and discusses appropriate resuscitative measures. From there, specific medications and common fetal effects are explored from start of labor through delivery. Medications for treatment of preeclampsia, induction of labor, and pain relief during labor are discussed.
Non-obstetric Surgery During Pregnancy
Authors: Karuppiah Arunthevaraja , Galey Jessica , Bharadwaj Shobana
Published: May 2021

Caring for the pregnant patient presenting for non-obstetric surgery presents the anesthesiologist with a unique challenge, as the needs of both the pregnant woman and her fetus must be considered within the context of the surgical procedure being performed. A pregnant woman should never be denied medically necessary surgery or have that surgery delayed regardless of trimester because this can adversely affect the pregnant woman and her fetus. The main goals in the anesthetic management of these patients are to apply maternal physiologic changes, avoid uteroplacental hypoperfusion and/or fetal hypoxemia, avoid teratogenic agents, and prevent preterm labor. A multidisciplinary approach involving surgical, anesthesiology, and obstetric teams is essential for decisions on the timing of the procedure and intraoperative fetal and uterine monitoring. Fetal heart rate monitoring may assist in maternal positioning and cardiorespiratory management and may influence a decision to deliver the fetus. No currently used anesthetic agents have been shown to have any teratogenic effects in humans at any gestational age when using standard concentrations.
Overview
Authors: Benarroch Eduardo E.
Published: May 2021

The nervous system consists of neurons, glial cells, blood vessels, and extracellular matrix. Neurons are electrically excitable cells and are primarily responsible for initiation, processing, and transmission of information. However, their function is affected by their reciprocal interactions with glial cells, which contribute to development, survival, and plasticity of synaptic connections and shape the activity of neuronal ensembles and systems critical for cognition and behavior. Advances in molecular, cellular, and electrophysiological approaches have provided major insight not only in normal function of neurons and glial cells but also in the pathophysiology of neurologic diseases at the molecular, synaptic, cellular network, and system levels.
Messenger RNA Metabolism
Authors: Benarroch Eduardo E.
Published: May 2021

Metabolism of messenger RNA (mRNA) is critical for control of cell phenotype and includes several steps: transcription of DNA into a pre-mRNA, mRNA maturation, nucleocytoplasmic export and transport to specific cellular locations, translation into proteins, and decay. All these steps are seamlessly integrated and controlled by a large number of RNA-binding proteins that interact with RNA, forming messenger ribonucleoprotein particles. Several noncoding RNAs, such as microRNAs, also regulate mRNA metabolism. Activity-dependent control of mRNA transcription, splicing, and translation are critical for growth, plasticity, and repair in the nervous system. Disorders of RNA metabolism are a major disease pathway for a large number of neurologic disorders, many of them associated with accumulation of stress granules containing RNA and associated proteins. Elucidation of the pathophysiology of some of these disorders provides novel approaches for their treatment, including antisense oligonucleotide therapy.
Proteostasis
Authors: Benarroch Eduardo E.
Published: May 2021

Normal cell function and survival depend on carefully regulated synthesis, folding, trafficking, and degradation of proteins. The balance among these processes is referred to as proteostasis. Proteins undergo maturation and folding in the endoplasmic reticulum. This process is error-prone and can be affected by mutations, errors during transcription or translation, and cellular stressors. Several interacting mechanisms, including the endoplasmic reticulum stress response, the unfolded protein response, and degradation by the ubiquitin-proteasome and the autophagosome-lysosome systems prevent the accumulation of misfolded proteins. Protein misfolding and incorporation into fibrillary structures is a fundamental mechanism of many neurodegenerative disorders. Degeneration results from toxic gain-of-function of the intermediate fibril monomers, promoting the formation of aggregates and initiating a cascade of protein–protein interactions leading to neuronal dysfunction and death, associated with neuroinflammation. These protein aggregates may serve as templates or seeds to elicit aggregation of their respective normal endogenous partners in neighboring cells, leading to disease propagation.
Mitochondria and Energy Metabolism
Authors: Benarroch Eduardo E.
Published: May 2021

Mitochondria are membranous organelles critical for survival and function of neurons and other cells in the nervous system and many other tissues. Their main functions include production of ATP by oxidative phosphorylation, signaling via reactive oxygen species; intracellular calcium (Ca2+) homeostasis; synthesis of iron-sulfur (Fe-S) clusters; metabolism of lipids and amino acids, and synthesis of nucleotides, and heme. Maintenance of normal mitochondrial function and distribution is known as mitostasis, and requires highly regulated processes of mitochondrial biogenesis and quality control, fusion/fission, transport, and mitophagy. Mitochondrial dysfunction is a critical mechanism of neurologic diseases. They include disorders directly affecting OXPHOS and metabolic functions; primary disorders of mitostasis; and most adult-onset neurodegenerative disorders indirectly affecting mitostasis through defects in axonal transport and autophagy.
Cholinergic Transmission
Authors: Benarroch Eduardo E.
Published: May 2021

Acetylcholine (ACh) is a major neurotransmitter in the central and peripheral nervous systems. Cholinergic neurons in the central nervous system include the basal forebrain cholinergic group that projects to the cerebral cortex and has a major role in attention, sensory processing, and memory; the mesopontine group that projects to the thalamus, basal ganglia, and brainstem areas and is involved in arousal, reward, and control of muscle tone; and large aspiny neurons of the striatum controlling basal ganglia function. In the periphery, ACh is the neurotransmitter of motor neurons innervating skeletal muscle; preganglionic neurons innervating autonomic ganglia; and parasympathetic, enteric, and sudomotor sympathetic neurons. Acetylcholine acts via nicotinic receptors to elicit fast excitation and several subtypes of muscarinic receptors that exert a variety of modulatory actions. Given the widespread distribution and targets of ACh, cholinergic systems have a major role in a variety of neurologic disorders, including Alzheimer disease, neuromuscular transmission defects, and autonomic manifestation of autoimmune diseases, drugs, or toxins.
Monoaminergic Systems
Authors: Benarroch Eduardo E.
Published: May 2021

Central monoaminergic systems are involved in behavioral arousal, attention, motivation, and control of motor, nociceptive, and autonomic processing. They include dopaminergic, noradrenergic, serotonergic, and histaminergic neurons with cell bodies in restricted areas of the brainstem and hypothalamus and widespread axonal projections targeting multiple brain regions. Via their multiple receptor mechanisms, these systems exert a complex and behavioral-state-dependent modulation of excitability of neurons and neuronal networks. In the periphery, norepinephrine is the major neurotransmitter of the sympathetic system. Monoaminergic systems are affected in genetic disorders of monoamine metabolism, neurodegenerative conditions, and psychiatric disorders. These systems are also a major target for pharmacologic therapy.
Microglia and Neuroinflammation
Authors: Benarroch Eduardo E.
Published: May 2021

Microglia maintain cellular, synaptic, and myelin homeostasis during development and normal function and response to injury. Surveilling icroglia actively explore their environment by dynamically extending thin processes that respond to local signals. Activated (“reactive,” or “effector”) microglia constitute a heterogeneous population that dynamically change in phenotype depending on their environmental context and may mediate either injury or neuroprotection, repair, and circuit refinement. Any type of injury in the CNS elicits activation of microglia, astrocytes, and oligodendrocyte precursors, which together with infiltrating cells from the blood in the case of blood-brain barrier disruption interact via several signals to elicit elimination of pathogens, limit the spatial extent of the lesion, and eventually promote tissue remodeling, repair, and remyelination. Neuroinflammation is a feature of essentially all types of neurologic disorders, including traumatic, vascular, and inflammatory/demyelinating lesions; autoimmune encephalitis; and neurodegenerative disorders and has a major role in mechanisms of epilepsy and pain.
Neocortical Organization and Circuits
Authors: Benarroch Eduardo E.
Published: May 2021

The cerebral cortex consists of multiple areas that differ from each other in terms of microstructural architecture, functional specialization, connectivity with other areas, and topographic organization. All cortical areas share a fundament cell composition, consisting of excitatory (principal) projection neurons, primarily pyramidal neurons, and different subtypes of local inhibitory GABAergic interneurons. Most pyramidal neurons participate in intra- or interhemispheric corticocortical connections; some project to subcortical targets, including the thalamus, basal ganglia, brainstem, and spinal cord. The different subtypes of GABAergic interneurons participate in feedforward, feedback, and disinhibitory circuits by targeting different domains of the principal cells and other GABAergic interneurons. Processing of information in the cerebral cortex critically depends on the precise synchronization of neuronal ensembles, both within local networks and across relatively long distances between separate brain regions. The interactions between principal cells and GABAergic interneurons have a critical role in determining these coordinated cortical oscillations. Dysfunction of these cortical circuits is at the core of many neurologic and psychiatric disorders, including seizures, dementia, and schizophrenia, to name a few.
Hippocampal and Amygdala Circuits
Authors: Benarroch Eduardo E.
Published: May 2021

The hippocampus and the amygdala are medial temporal lobe structures that constitute core elements of the so-called limbic system. The hippocampus and its cortical connections form a posterior limbic circuit critical for encoding, storage, and retrieval of episodic and visuospatial memory. The amygdala and its cortical and subcortical connections form an anterior limbic circuit involved in emotional processing and social behavior. The intrinsic circuits of both the hippocampus and the amygdala consist of serial excitatory connections strongly regulated by local GABAergic neurons. Due to their relatively simple organization, the circuits of the hippocampus and amygdala have been extensively studied and provided the basis for elucidation of mechanisms of synaptic plasticity and learning. The hippocampus and amygdala are strongly interconnected with each other both anatomically and functionally, and they are both affected in disorders manifested with abnormal memory and emotional processing, such as mesial temporal lobe epilepsy and limbic encephalitis.
Thalamus and Thalamocortical Interactions
Authors: Benarroch Eduardo E.
Published: May 2021

The thalamus is critical for the routing of information and coordinating the forebrain activity responsible for arousal, attention, sensory processing, motor control, cognition, and behavior. It contains first-order relay nuclei that selectively project to modality-specific primary cortical sensory areas, high-order relay nuclei that participate in cortico-thalamo-cortical interactions for attention and high-level cognitive processing, motor nuclei that mediate influences of the cerebellum and basal ganglia, and intralaminar and midline nuclei that participate global cortical activation and control the function of the striatum. All these nuclei provide excitatory inputs to the cortex via thalamocortical neurons. Thalamocortical activity is controlled by GABAergic neurons of the reticular nucleus of the thalamus, which regulate the firing pattern of thalamocortical neurons during the sleep-wake cycle and in the setting of selective attention. Extrathalamic GABAergic, cholinergic, and monoaminergic inputs also strongly regulate the thalamic circuits in a behavioral state-dependent manner. Disruption in thalamocortical circuits is a major mechanism in disorders of impaired awareness such as absence and temporal lobe seizures and in the pathophysiology of cognitive disorders.
Vascular Anesthesia Procedures
Authors: Urman Richard , Kaye Alan
Published: May 2021

This book reviews the practice of vascular anesthesia, which is now increasingly recognized as a subspecialty of anesthesia, and looks at developments and latest evidence in neuraxial, regional, and general anesthesia techniques. It explores essential topics on vascular anatomy, common vascular procedures, and anesthetic techniques in general and regional anesthesia. It also includes subjects relating to complications, perioperative patient monitoring, and post-operative management. The book begins with an analysis of the basic vascular anatomy and physiology, which covers the three components of the vascular system where oxygen, nutrients, and metabolites exchange: artery, vein, and capillaries. It ends with the anesthetic approach on patients that are presented for vascular surgery and considered to be a very sick, comorbid population with higher ASA classification.
Hemostasis, Thrombosis, Transfusion, and Blood Conservation
Authors: Henderson Reney A.
Published: May 2021

In vascular surgical procedures, there is a balance of anticoagulation and coagulation that must take place for a successful surgery. This chapter reviews goals in coagulation and hemostasis in vascular surgery. For vascular surgery, patients must be anticoagulated to inhibit occlusion and thrombosis of vasculature. Once the procedure is completed, anticoagulation must be reversed to obtain hemostasis. The method to regain hemostasis varies and can be by the administration of reversal agents, hemostatic agents, or allogenic blood products. This process can sometimes be simplified by using thromboelastography as a guide for treatment. This chapter also touches on blood conservation (cell salvaging techniques) and the use of alternative blood products.
Invasive Anesthesia Procedures for Perioperative Care
Authors: Kuo Frederick H. , Nikolaidis Melissa , Deng Yi
Published: May 2021

Patients presenting for vascular surgery frequently have multiple comorbidities associated with increased surgical risk. Additionally, certain types of vascular surgery can induce stress on the patient and create increased risk for complications. These factors often necessitate closer monitoring to facilitate early intervention. The anesthesiologist may elect to perform certain invasive procedures to aid in perioperative care. Procedures reviewed include placement of peripheral intravenous catheters, arterial catheters, central venous catheters, pulmonary artery catheters, and lumbar cerebrospinal fluid drains. For each procedure, this chapter discusses clinical applications, contraindications, site selection, required equipment and setup, placement techniques, potential usage of ultrasound guidance, and possible complications.
Regional Anesthesia
Authors: Herzig Samuel , Medrano Elilary Montilla , Gritchenko Karina
Published: May 2021

Patients presenting for vascular surgery typically have significant comorbidities. Procedures can vary from minor to quite large with significant blood loss and fluid shifts, and can be elective or emergent. Perioperative morbidity and mortality in the context of co-existing cardiovascular disease, diabetes, dementia and other factors all provide great concern to the anesthesiologist in their approach towards the vascular patient. The anesthetic approach to such patients must therefore be taken with great forethought. Many times, these procedures can be localized to a particular extremity or well-defined set of dermatomes, and regional anesthesia has become one important option for the complicated vascular patient. In this chapter, the risks, benefits, and feasibility of various regional techniques are discussed in the context of patients presenting for carotid endarterectomy, vascular access placement, and major lower extremity vascular surgery.