Publications by authors named "Christopher Davis"

371 Publications

A guide to the Tx of cellulitis and other soft-tissue infections.

J Fam Pract 2021 06;70(5):214-219

Penn State Health Milton S. Hershey Medical Center, Hershey.

Diagnostic and therapeutic priorities vary for the 8 types of infection reviewed.
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http://dx.doi.org/10.12788/jfp.0198DOI Listing
June 2021

Digital restoration of the Wilson-Leonard 2 Paleoindian skull (~10,000 BP) from central Texas with comparison to other early American and modern crania.

Am J Phys Anthropol 2021 Aug 2. Epub 2021 Aug 2.

Department of Anthropology, The University of Texas at Austin, Austin, Texas, USA.

Objectives: Craniofacial morphology (CFM) is often used to address questions about the biological affinities of the earliest Americans, or Paleoindians, but resolution is complicated in part by a lack of well-preserved crania. The Wilson-Leonard 2 (WL-2) Paleoindian skull from Texas has never been fully analyzed because it is crushed and cannot be physically reconstructed. This study employs a digital restoration for comprehensive assessment and analysis of WL-2.

Materials And Methods: High-resolution CT data and geometric morphometrics are used to restore the WL-2 skull and analyze its morphology using 65 craniometric measurements acquired on the restoration. These data allow for a full morphological description and multivariate (Mahalanobis Distance and Principal Component) comparisons to other Paleoindians and recent populations.

Results: WL-2 has a long, narrow braincase, and a short, modestly prognathic face. Compared with other Paleoindians, she is individually similar to several skulls from Brazil, but aligns most closely with pooled samples from the US and Mexico. WL-2 is most similar to recent populations from Europe, Asia, and the Americas, and markedly different to those from Africa and Australia.

Discussion: The overall morphology of WL-2 and her association with Asians and Europeans align well with trends identified in other CFM analyses. Her affinity to recent Amerindians contrasts with the findings of many previous CFM studies, but is seemingly consistent with molecular analyses suggesting a close relationship between some Paleoindians and modern American Indians. This study demonstrates the potential for using digital anthropological methods to study other Paleoindian crania whose data value is limited by physical destruction and/or deformation.
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http://dx.doi.org/10.1002/ajpa.24379DOI Listing
August 2021

On being loyal to a casino: The interactive influence of tier status and disordered gambling symptomatology on attitudinal and behavioral loyalty.

J Behav Addict 2021 Jul 21. Epub 2021 Jul 21.

1Carleton University,Canada.

Background And Aims: Casino loyalty programs are marketing strategies designed to foster attitudinal (i.e., identification and satisfaction) and behavioral (i.e., spending) loyalty among gamblers by offering rewards to members. Casino loyalty programs use a tier-based structure to segment members who spend more money into higher tiers, where they receive better rewards (compared to lower tiered members). Tier-based structures may encourage increased expenditure among patrons, especially among players living with a gambling disorder. The current work aimed to examine whether tier status and disordered gambling symptomatology interact to predict attitudinal and behavioral loyalty.

Methods: Study 1 used a cross-sectional design to examine whether tier status and disordered gambling symptomatology interact to predict self-reported loyalty among a sample of American casino loyalty program members (N = 396). In Study 2, archival player account data from Canadian casino loyalty program members (N = 649) were analyzed to examine whether tier status and disordered gambling symptomatology interact to predict objective measures of behavioral loyalty.

Results: The greatest effect of tier status on attitudinal and behavioral loyalty was observed among non-problem gamblers in the highest tiers. Tier status, however, did not influence loyalty among members high in disordered gambling symptomatology.

Discussion: Results suggest that once gambling has become problematic, loyalty programs may not influence player attitudes and behaviors. Non-problem gamblers may be particularly susceptible to the tiered structure of the programs.

Conclusion: Non-problem gamblers may benefit from casino loyalty programs in the short-term but longitudinal research is needed to understand the long-term influence of membership.
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http://dx.doi.org/10.1556/2006.2021.00046DOI Listing
July 2021

Telehealth in emergency medicine: A consensus conference to map the intersection of telehealth and emergency medicine.

Acad Emerg Med 2021 Jul 10. Epub 2021 Jul 10.

Department of Emergency Medicine, Thomas Jefferson University, Philadelphia, PA, USA.

Introduction: Telehealth has the potential to significantly change the specialty of emergency medicine (EM) and has rapidly expanded in EM during the COVID pandemic; however, it is unclear how EM should intersect with telehealth. The field lacks a unified research agenda with priorities for scientific questions on telehealth in EM.

Methods: Through the 2020 Society for Academic Emergency Medicine's annual consensus conference, experts in EM and telehealth created a research agenda for the topic. The multiyear process used a modified Delphi technique to develop research questions related to telehealth in EM. Research questions were excluded from the final research agenda if they did not meet a threshold of at least 80% of votes indicating "important" or "very important."

Results: Round 1 of voting included 94 research questions, expanded to 103 questions in round 2 and refined to 36 questions for the final vote. Consensus occurred with a final set of 24 important research questions spanning five breakout group topics. Each breakout group domain was represented in the final set of questions. Examples of the questions include: "Among underserved populations, what are mechanisms by which disparities in emergency care delivery may be exacerbated or ameliorated by telehealth" (health care access) and "In what situations should the quality and safety of telehealth be compared to in-person care and in what situations should it be compared to no care" (quality and safety).

Conclusion: The primary finding from the process was the breadth of gaps in the evidence for telehealth in EM and telehealth in general. Our consensus process identified priority research questions for the use of and evaluation of telehealth in EM to fill the current knowledge gaps. Support should be provided to answer the research questions to guide the evidenced-based development of telehealth in EM.
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http://dx.doi.org/10.1111/acem.14330DOI Listing
July 2021

F-6-Fluoro-l-Dopa PET/CT Imaging of Congenital Hyperinsulinism.

J Nucl Med 2021 Jul;62(Suppl 2):51S-56S

Radiology Department, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania; and.

Congenital hyperinsulinism is characterized by persistent hypoglycemia due to inappropriate excess secretion of insulin resulting in hyperinsulinemic hypoglycemia. The clinical course varies from mild to severe, with a significant risk for brain damage. Imaging plays a valuable role in the care of infants and children with severe hypoglycemia unresponsive to medical therapy. F-6-fluoro-l-dopa PET/CT is the method of choice for the detection and localization of a focal lesion of hyperinsulinism. Surgical resection of a focal lesion can lead to a cure with limited pancreatectomy. This article reviews the role of F-6-fluoro-l-dopa PET/CT in the management of this vulnerable population.
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http://dx.doi.org/10.2967/jnumed.120.246033DOI Listing
July 2021

Factors promoting greater preoccupation with a secret.

Br J Soc Psychol 2021 May 20. Epub 2021 May 20.

Department of Psychology, Carleton University, Ottawa, Ontario, Canada.

The secrets that are most taxing to one's health and well-being are those that are the most preoccupying to the secret-keeper. However, it is currently unclear what makes a secret preoccupying. We conducted a four-wave longitudinal study to assess four factors that should contribute to one's degree of preoccupation with a secret kept from one's spouse/romantic partner: perceived cost of revealing the secret, frequency of cues, fear of discovery, and individual differences in self-concealment. Multilevel modelling of data from an online sample of 143 adults (51% women, 49% men; M  = 39.9, SD = 9.3) keeping a secret from their spouse/partner indicated that all four factors independently and positively predict greater preoccupation with a secret. Further, the first three factors also significantly predicted how preoccupied one would be with one's secret two weeks later, taking into account how preoccupied one was with the secret at present. We conclude that the characteristics of the secret, as well as the secret-keeper, can contribute to how preoccupying a secret is to an individual.
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http://dx.doi.org/10.1111/bjso.12462DOI Listing
May 2021

Hepatitis E virus: Whole genome sequencing as a new tool for understanding HEV epidemiology and phenotypes.

J Clin Virol 2021 Jun 27;139:104738. Epub 2021 Jan 27.

MRC-University of Glasgow Centre for Virus Research, Glasgow, UK; Microbiology Department, Laboratoire National de Sante, Dudelange, Luxembourg. Electronic address:

Hepatitis E Virus (HEV) is emerging as a public health concern across Europe and tools for complete genome data to aid epidemiological and virulence analysis are needed. The high sequence heterogeneity observed amongst HEV genotypes has restricted most analyses to subgenomic regions using PCR-based methods, which can be unreliable due to poor primer homology. We designed a panel of custom-designed RNA probes complementary to all published HEV full genome NCBI sequences. A target enrichment protocol was performed according to the NimbleGen® standard protocol for Illumina® library preparation. Optimisation of this protocol was performed using 40 HEV RNA-positive serum samples and the World Health Organization International Reference Panel for Hepatitis E Virus RNA Genotypes for Nucleic Acid Amplification Technique (NAT)-Based Assays and related reference materials. Deep sequencing using this target enrichment protocol resulted in whole genome consensus sequences from samples with a viral load range of 1.25 × 10-1.17 × 10 IU/mL. Phylogenetic analysis of these sequences recapitulated and extended the partial genome results obtained from genotyping by Sanger sequencing (genotype 1, ten samples and genotype 3, 30 samples). The protocol is highly adaptable to automation and could be used to sequence full genomes of large sample numbers. A more comprehensive understanding of hepatitis E virus transmission, epidemiology and viral phenotype prediction supported by an efficient method of sequencing the whole viral genome will facilitate public health initiatives to reduce the prevalence and mitigate the harm of HEV infection in Europe.
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http://dx.doi.org/10.1016/j.jcv.2021.104738DOI Listing
June 2021

Modelling to Quantify the Likelihood that Local Elimination of Transmission has Occurred Using Routine Gambiense Human African Trypanosomiasis Surveillance Data.

Clin Infect Dis 2021 06;72(Suppl 3):S146-S151

Mathematics Institute, University of Warwick, Coventry, United Kingdom.

Background: The gambiense human African trypanosomiasis (gHAT) elimination programme in the Democratic Republic of Congo (DRC) routinely collects case data through passive surveillance and active screening, with several regions reporting no cases for several years, despite being endemic in the early 2000s.

Methods: We use mathematical models fitted to longitudinal data to estimate the probability that selected administrative regions have already achieved elimination of transmission (EOT) of gHAT. We examine the impact of active screening coverage on the certainty of model estimates for transmission and therefore the role of screening in the measurement of EOT.

Results: In 3 example health zones of Sud-Ubangi province, we find there is a moderate (>40%) probability that EOT has been achieved by 2018, based on 2000-2016 data. Budjala and Mbaya reported zero cases during 2017-18, and this further increases our respective estimates to 99.9% and 99.6% (model S) and to 87.3% and 92.1% (model W). Bominenge had recent case reporting, however, that if zero cases were found in 2021, it would substantially raise our certainty that EOT has been met there (99.0% for model S and 88.5% for model W); this could be higher with 50% coverage screening that year (99.1% for model S and 94.0% for model W).

Conclusions: We demonstrate how routine surveillance data coupled with mechanistic modeling can estimate the likelihood that EOT has already been achieved. Such quantitative assessment will become increasingly important for measuring local achievement of EOT as 2030 approaches.
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http://dx.doi.org/10.1093/cid/ciab190DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8201550PMC
June 2021

The Case for Virtual Sepsis Surveillance and Intervention.

Telemed J E Health 2021 Apr 7. Epub 2021 Apr 7.

Department of Emergency Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA.

To determine whether deployment of an integrated virtual sepsis surveillance program could improve time to antibiotics and mortality in a longitudinal cohort of non-present on admission (NPOA) sepsis cases. We used an uncontrolled pre- and poststudy design to compare time to antibiotics and mortality between a time-based cohort of NPOA sepsis cases separated by the deployment of a virtual sepsis surveillance program. A total of 566 NPOA sepsis cases were included in this study. Three hundred and thirty-five cases compromised the preintervention arm, whereas the postintervention cohort included 231 cases. After deployment of the virtual sepsis surveillance program, median time to antibiotics improved from 92 to 59 min ( < 0.001). Mortality was reduced from 30% to 21% ( = 0.015). Deployment of a virtual sepsis surveillance program resulted in a decreased time to antibiotics and an overall reduction in NPOA sepsis mortality.
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http://dx.doi.org/10.1089/tmj.2020.0513DOI Listing
April 2021

Cost-effectiveness modelling to optimise active screening strategy for gambiense human African trypanosomiasis in endemic areas of the Democratic Republic of Congo.

BMC Med 2021 Apr 1;19(1):86. Epub 2021 Apr 1.

Mathematics Institute, University of Warwick, Coventry, CV4 7AL, UK.

Background: Gambiense human African trypanosomiasis (gHAT) has been brought under control recently with village-based active screening playing a major role in case reduction. In the approach to elimination, we investigate how to optimise active screening in villages in the Democratic Republic of Congo, such that the expenses of screening programmes can be efficiently allocated whilst continuing to avert morbidity and mortality.

Methods: We implement a cost-effectiveness analysis using a stochastic gHAT infection model for a range of active screening strategies and, in conjunction with a cost model, we calculate the net monetary benefit (NMB) of each strategy. We focus on the high-endemicity health zone of Kwamouth in the Democratic Republic of Congo.

Results: High-coverage active screening strategies, occurring approximately annually, attain the highest NMB. For realistic screening at 55% coverage, annual screening is cost-effective at very low willingness-to-pay thresholds (20.4 per disability adjusted life year (DALY) averted), only marginally higher than biennial screening (14.6 per DALY averted). We find that, for strategies stopping after 1, 2 or 3 years of zero case reporting, the expected cost-benefits are very similar.

Conclusions: We highlight the current recommended strategy-annual screening with three years of zero case reporting before stopping active screening-is likely cost-effective, in addition to providing valuable information on whether transmission has been interrupted.
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http://dx.doi.org/10.1186/s12916-021-01943-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8017623PMC
April 2021

Vitamin A-fortified rice increases total body vitamin A stores in lactating Thai women measured by retinol isotope dilution: a double-blind, randomized, controlled trial.

Am J Clin Nutr 2021 05;113(5):1372-1380

Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI, USA.

Background: Lactating women are at increased risk for vitamin A (VA) deficiency due to demands for breast milk content and limited hepatic stores for women in some countries. Previously, consumption of triple-fortified rice, which included VA, iron, and zinc, successfully improved the VA status of Thai children in whom their total body VA stores (TBSs) were doubled in 2 mo.

Objective: This study assessed the efficacy of consuming VA-fortified rice, which delivered 500 µg retinol activity equivalents (RAEs)/d, on TBSs and estimated total liver VA reserves (TLRs) in Thai lactating women using the retinol isotope dilution (RID) test.

Methods: A randomized controlled trial was conducted with 70 lactating women (n = 35/group) who received either VA-fortified rice (500 µg RAEs/d) or unfortified rice for 14 wk on weekdays only. Serum retinol concentrations (SRs), C-reactive protein, and TBSs were assessed before and after the intervention. The paired 13C-RID test was used to measure TBSs. After a baseline blood sample, 2.0 µmol [14,15]-13C2-retinyl acetate was administered orally. A follow-up blood sample was drawn 14 d later. The RID test was repeated after the intervention.

Results: TBSs increased significantly (P < 0.05) in the intervention group from 240 (182, 316) to 331 (251, 447) [geometric means (95% CIs)] µmol retinol, and this change in TBSs was significantly higher (P < 0.05) than that in the control group [+52.9 (-74, 453) compared with -4.3 (-106, 275) µmol retinol]. Estimated TLRs indicated a high prevalence of VA deficiency among these lactating women. Initial and final SRs did not differ by group and did not change over the course of the intervention.

Conclusion: VA-fortified rice improved the VA status of lactating women by increasing TBSs. A targeted approach to disseminate VA interventions among vulnerable groups should be considered in some contexts. This trial was registered at clinicaltrials.gov as NCT03056625.
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http://dx.doi.org/10.1093/ajcn/nqaa418DOI Listing
May 2021

Real-World Outcomes of DAA Treatment and Retreatment in UK-based Patients Infected with HCV Genotypes/Subtypes Endemic in Africa.

J Infect Dis 2021 Mar 1. Epub 2021 Mar 1.

MRC-University of Glasgow Centre for Virus Research, Glasgow, UK.

Background: Chronic HCV infection affects 71 million individuals, mostly residing in low- and middle-income countries (LMICs). Direct-acting antivirals (DAA) give high rates of sustained virological response (SVR) in high income countries where a restricted range of HCV genotypes/subtypes circulate.

Approach: We studied UK-resident patients born in Africa to examine DAA effectiveness in LMICs where there is far greater breadth of HCV genotypes/subtypes. Viral genome sequences were determined from 233 patients.

Results: Full-length viral genomic sequences for 26 known subtypes and 5 previously unidentified isolates covering 5 HCV genotypes were determined. From 149 patients who received DAA treatment/retreatment, the overall SVR was 93%. Treatment failure was associated primarily with two subtypes, gt1l and gt4r, using Sofosbuvir/Ledipasvir. These subtypes contain natural resistance-associated variants that likely contribute to poor efficacy with this drug combination. Treatment failure was also significantly associated with hepatocellular carcinoma.

Conclusions: DAA combinations give high SVR rates despite the high HCV diversity across the African continent except for subtypes gt1l and gt4r, which respond poorly to Sofosbuvir/Ledipasvir. These subtypes are widely distributed across Western, Central and Eastern Africa. Thus, in circumstances where accurate genotyping is absent, Ledipasvir and its generic compounds should not be considered as a recommended treatment option.
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http://dx.doi.org/10.1093/infdis/jiab110DOI Listing
March 2021

Stem vacuole-targetted sucrose isomerase enhances sugar content in sorghum.

Biotechnol Biofuels 2021 Mar 1;14(1):53. Epub 2021 Mar 1.

Centre for Crop Science, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Brisbane, 4072, Queensland, Australia.

Background: Sugar content is critically important in determining sugar crop productivity. However, improvement in sugar content has been stagnant among sugar crops for decades. Sorghum, especially sweet sorghum with high biomass, shown great potential for biofuel, has lower sugar content than sugarcane. To enhance sugar content, the sucrose isomerase (SI) gene, driven by stem-specific promoters (A2 or LSG) with a vacuole-targetted signal peptide, was transformed into the sorghum inbred line (T×430).

Results: The study demonstrated that transgenic lines of grain sorghum, containing 50-60% isomaltulose, accumulated up to eightfold (1000 mM) more total sugar than the control T×430 did (118 mM) in stalks of T generation. Subsequently, the elite engineered lines (A5, and LSG9) were crossed with sweet sorghum (Rio, and R9188). Total sugar contents (over 750 mM), were notably higher in F, and F progenies than the control Rio (480 mM). The sugar contents of the engineered lines (over 750 mM), including T, T, F, and F, are surprisingly higher than that of the field-grown sugarcane (normal range 600-700 mmol/L). Additionally, analysis of physiological characterization demonstrated that the superior progenies had notably higher rates of photosynthesis, sucrose transportation, and sink strength than the controls.

Conclusions: The genetic engineering approach has dramatically enhanced total sugar content in grain sorghum (T, and T) and hybrid sorghum (F, and F), demonstrating that sorghum can accumulate as high or higher sugar content than sugarcane. This research illustrates that the SI gene has enormous potential on improvement of sugar content in sorghum, particularly in hybirds and sweet sorghum. The substantial increase on sugar content would lead to significant financial benefits for industrial utilization. This study could have a substantial impact on renewable bioenergy. More importantly, our results demonstrated that the phenotype of high sugar content is inheritable and shed light on improvement for other sugar crops.
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http://dx.doi.org/10.1186/s13068-021-01907-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7923521PMC
March 2021

Predicting the impact of COVID-19 interruptions on transmission of gambiense human African trypanosomiasis in two health zones of the Democratic Republic of Congo.

Trans R Soc Trop Med Hyg 2021 03;115(3):245-252

Zeeman Institute (SBIDER), University of Warwick, Mathematical Sciences Building, Gibbet Hill Road, Coventry, CV4 7AL, UK.

Many control programmes against neglected tropical diseases have been interrupted due to the coronavirus disease 2019 (COVID-19) pandemic, including those that rely on active case finding. In this study we focus on gambiense human African trypanosomiasis (gHAT), where active screening was suspended in the Democratic Republic of Congo (DRC) due to the pandemic. We use two independent mathematical models to predict the impact of COVID-19 interruptions on transmission and reporting and achievement of the 2030 elimination of transmission (EOT) goal for gHAT in two moderate-risk regions of the DRC. We consider different interruption scenarios, including reduced passive surveillance in fixed health facilities, and whether this suspension lasts until the end of 2020 or 2021. Our models predict an increase in the number of new infections in the interruption period only if both active screening and passive surveillance were suspended, and with a slowed reduction-but no increase-if passive surveillance remains fully functional. In all scenarios, the EOT may be slightly pushed back if no mitigation, such as increased screening coverage, is put in place. However, we emphasise that the biggest challenge will remain in the higher-prevalence regions where EOT is already predicted to be behind schedule without interruptions unless interventions are bolstered.
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http://dx.doi.org/10.1093/trstmh/trab019DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7928583PMC
March 2021

Comparing semi-landmarking approaches for analyzing three-dimensional cranial morphology.

Am J Phys Anthropol 2021 05 23;175(1):227-237. Epub 2021 Jan 23.

Department of Pediatrics, University of Washington, Seattle, Washington, USA.

Objectives: Increased use of three-dimensional (3D) imaging data has led to a need for methods capable of capturing rich shape descriptions. Semi-landmarks have been demonstrated to increase shape information but placement in 3D can be time consuming, computationally expensive, or may introduce artifacts. This study implements and compares three strategies to more densely sample a 3D image surface.

Materials And Methods: Three dense sampling strategies: patch, patch-thin-plate spline (TPS), and pseudo-landmark sampling, are implemented to analyze skulls from three species of great apes. To evaluate the shape information added by each strategy, the semi or pseudo-landmarks are used to estimate a transform between an individual and the population average template. The average mean root squared error between the transformed mesh and the template is used to quantify the success of the transform.

Results: The landmark sets generated by each method result in estimates of the template that on average were comparable or exceeded the accuracy of using manual landmarks alone. The patch method demonstrates the most sensitivity to noise and missing data, resulting in outliers with large deviations in the mean shape estimates. Patch-TPS and pseudo-landmarking provide more robust performance in the presence of noise and variability in the dataset.

Conclusions: Each landmarking strategy was capable of producing shape estimations of the population average templates that were generally comparable to manual landmarks alone while greatly increasing the density of the shape information. This study highlights the potential trade-offs between correspondence of the semi-landmark points, consistent point spacing, sample coverage, repeatability, and computational time.
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http://dx.doi.org/10.1002/ajpa.24214DOI Listing
May 2021

Conversion of Existing UVB Phototherapy Units to UVC Germicidal Chambers for N95 Decontamination: Lessons Learned.

Photobiomodul Photomed Laser Surg 2021 Feb 21;39(2):83-85. Epub 2021 Jan 21.

Greater Boston Pandemic Fabrication Team (PanFab) c/o Harvard-MIT Center for Regulatory Science, Harvard Medical School, Boston, Massachusetts, USA.

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http://dx.doi.org/10.1089/photob.2020.4968DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8106246PMC
February 2021

Lassa Virus Circulation in Small Mammal Populations in Bo District, Sierra Leone.

Biology (Basel) 2021 Jan 5;10(1). Epub 2021 Jan 5.

Department of Virology, Bernhard Nocht Institute for Tropical Medicine, 20359 Hamburg, Germany.

Lassa fever is a viral hemorrhagic fever caused by the Lassa virus LASV, which was first isolated in the rodent in 1974 in Kenema, Sierra Leone. As little is known about the abundance and the presence of LASV in rodents living in the Bo area, we carried out a small mammal longitudinal population survey. A standardized trapping session was performed in various habitats and seasons in six villages over two years (2014-2016) and samples collected were tested for arenavirus IgG and LASV. A Bayesian phylogenetic analysis was performed on sequences identified by PCR. A total of 1490 small mammals were collected, and 16 rodent species were identified, with (355, 24%) found to be the most prevalent species. Forty-one (2.8%) samples were IgG positive, and 31 of these were trapped in homes and 10 in surrounding vegetation. Twenty-nine of 41 seropositive rodents were We detected four LASV by PCR in two villages, all found in . Phylogenetic analysis showed that the sequences were distributed within the Sierra Leonean clade within lineage IV, distinguishing a Bo sub-clade older than a Kenema sub-clade. Compared to other settings, we found a low abundance of and a low circulation of LASV in rodents in villages around Bo district.
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http://dx.doi.org/10.3390/biology10010028DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7824740PMC
January 2021

Single prolonged stress blocks sleep homeostasis and pre-trauma sleep deprivation does not exacerbate the severity of trauma-induced fear-associated memory impairments.

PLoS One 2021 6;16(1):e0243743. Epub 2021 Jan 6.

Department of Biomedical Sciences, WSU Health Sciences Spokane, Elson S. Floyd College of Medicine, Spokane, Washington, United States of America.

Sleep is intimately linked to cognitive performance and exposure to traumatic stress that leads to post-traumatic stress disorder (PTSD) impairs both sleep and cognitive function. However, the contribution of pre-trauma sleep loss to subsequent trauma-dependent fear-associated memory impairment remains unstudied. We hypothesized that sleep deprivation (SD) prior to trauma exposure may increase the severity of a PTSD-like phenotype in rats exposed to single prolonged stress (SPS), a rodent model of PTSD. Rats were exposed to SPS alone, SD alone, or a combination of SPS+SD and measures of fear-associated memory impairments and vigilance state changes were compared to a group of control animals not exposed to SPS or SD. We found that SPS, and SPS+SD animals showed impaired fear-associated memory processing and that the addition of SD to SPS did not further exaggerate the effect of SPS alone. Additionally, the combination of SPS with SD results in a unique homeostatic sleep duration phenotype when compared to SD, SPS, or control animals. SPS exposure following SD represses homeostatic rebound and eliminates sleep-deprivation-induced increases in NREM sleep delta power. This work identifies a unique time frame where trauma exposure and sleep interact and identifies this window of time as a potential therapeutic treatment window for staving off the negative consequences of trauma exposure.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0243743PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7787370PMC
April 2021

Interventions for frostbite injuries.

Cochrane Database Syst Rev 2020 12 20;12:CD012980. Epub 2020 Dec 20.

Department of Surgery and Transplantation C2122, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.

Background: Frostbite is a thermal injury caused when tissue is exposed to sub-zero temperatures (in degrees Celsius) long enough for ice crystals to form in the affected tissue. Depending on the degree of tissue damage, thrombosis, ischaemia, necrosis (tissue death), gangrene and ultimately amputation may occur. Several interventions for frostbite injuries have been proposed, such as hyperbaric oxygen therapy, sympathectomy (nerve block), thrombolytic (blood-thinning) therapy and vasodilating agents such as iloprost, reserpine, pentoxifylline and buflomedil, but the benefits and harms of these interventions are unclear.

Objectives: To assess the benefits and harms of the different management options for frostbite injuries.

Search Methods: On 25 February 2020, we searched the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, Ovid MEDLINE(R), Ovid MEDLINE(R) In-Process & Other Non-Indexed Citations, Ovid MEDLINE(R) Daily and Ovid OLDMEDLINE(R), Embase (OvidSP), ISI Web of Science: Science Citation Index Expanded (SCI-EXPANDED), Conference Proceedings Citation Index-Science (CPCI-S), as well as trials registers. Shortly before publication, we searched Clinicaltrials.gov, the World Health Organization (WHO) International Clinical Trials Registry Platform, OpenGrey and GreyLit (9 November 2020) again. We investigated references from relevant articles, and corresponded with a trial author.

Selection Criteria: We included randomised controlled trials (RCTs) that compared any medical intervention, e.g. pharmacological therapy, topical treatments or rewarming techniques, for frostbite injuries to another treatment, placebo or no treatment.

Data Collection And Analysis: Two authors independently extracted data. We used Review Manager 5 for statistical analysis of dichotomous data with risk ratio (RR) with 95% confidence intervals (CIs). We used the Cochrane 'Risk of bias' tool to assess bias in the included trial. We assessed incidence of amputations, rates of serious and non-serious adverse events, acute pain, chronic pain, ability to perform activities of daily living, quality of life, withdrawal rate from medical therapy due to adverse events, occupational effects and mortality. We used GRADE to assess the quality of the evidence.

Main Results: We included one, open-label randomised trial involving 47 participants with severe frostbite injuries. We judged this trial to be at high risk of bias for performance bias, and uncertain risk for attrition bias; all other risk of bias domains we judged as low. All participants underwent rapid rewarming, received 250 mg of aspirin and 400 mg intravascular (IV) buflomedil (since withdrawn from practice), and were then randomised to one of three treatment groups for the following eight days. Group 1 received additional IV buflomedil 400 mg for one hour per day. Group 2 received the prostacyclin, iloprost, 0.5 ng to 2 ng/kg/min IV for six hours per day. Group 3 received IV iloprost 2 ng/kg/min for six hours per day plus fibrinolysis with 100 mg recombinant tissue plasminogen activator (rtPA) for the first day only. The results suggest that iloprost and iloprost plus rtPA may reduce the rate of amputations in people with severe frostbite compared to buflomedil alone, RR 0.05 (95% CI 0.00 to 0.78; P = 0.03; very low-quality evidence) and RR 0.31 (95% CI 0.10 to 0.94; P = 0.04; very low-quality evidence), respectively. Iloprost may be as effective as iloprost plus rtPA at reducing the amputation rate, RR 0.14 (95% CI 0.01 to 2.56; P = 0.19; very low-quality evidence). There were no reported deaths or withdrawals due to adverse events in any of the groups; we assessed evidence for both outcomes as being of very low quality. Adverse events (including flushing, nausea, palpitations and vomiting) were common, but not reported separately by comparator arm (very low-quality evidence). The included study did not measure the outcomes of acute pain, chronic pain, ability to perform activities of daily living, quality of life or occupational effects.

Authors' Conclusions: There is a paucity of evidence regarding interventions for frostbite injuries. Very low-quality evidence from a single small trial indicates that iloprost, and iloprost plus rtPA, in combination with buflomedil may reduce the need for amputation in people with severe frostbite compared to buflomedil alone. However, buflomedil has been withdrawn from use. High quality randomised trials are needed to establish firm evidence for the treatment of frostbite injuries.
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http://dx.doi.org/10.1002/14651858.CD012980.pub2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8092677PMC
December 2020

Bidirectional perisomatic inhibitory plasticity of a Fos neuronal network.

Nature 2021 02 9;590(7844):115-121. Epub 2020 Dec 9.

Department of Neurobiology, Harvard Medical School, Boston, MA, USA.

Behavioural experiences activate the FOS transcription factor in sparse populations of neurons that are critical for encoding and recalling specific events. However, there is limited understanding of the mechanisms by which experience drives circuit reorganization to establish a network of Fos-activated cells. It is also not known whether FOS is required in this process beyond serving as a marker of recent neural activity and, if so, which of its many gene targets underlie circuit reorganization. Here we demonstrate that when mice engage in spatial exploration of novel environments, perisomatic inhibition of Fos-activated hippocampal CA1 pyramidal neurons by parvalbumin-expressing interneurons is enhanced, whereas perisomatic inhibition by cholecystokinin-expressing interneurons is weakened. This bidirectional modulation of inhibition is abolished when the function of the FOS transcription factor complex is disrupted. Single-cell RNA-sequencing, ribosome-associated mRNA profiling and chromatin analyses, combined with electrophysiology, reveal that FOS activates the transcription of Scg2, a gene that encodes multiple distinct neuropeptides, to coordinate these changes in inhibition. As parvalbumin- and cholecystokinin-expressing interneurons mediate distinct features of pyramidal cell activity, the SCG2-dependent reorganization of inhibitory synaptic input might be predicted to affect network function in vivo. Consistent with this prediction, hippocampal gamma rhythms and pyramidal cell coupling to theta phase are significantly altered in the absence of Scg2. These findings reveal an instructive role for FOS and SCG2 in establishing a network of Fos-activated neurons via the rewiring of local inhibition to form a selectively modulated state. The opposing plasticity mechanisms acting on distinct inhibitory pathways may support the consolidation of memories over time.
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http://dx.doi.org/10.1038/s41586-020-3031-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7864877PMC
February 2021

Breast Milk-Derived Retinol Is a Potential Surrogate for Serum in the 13C-Retinol Isotope Dilution Test in Zambian Lactating Women with Vitamin A Deficient and Adequate Status.

J Nutr 2021 01;151(1):255-263

Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI, USA.

Background: Vitamin A (VA) deficiency (VAD) affects ∼19 million pregnant women worldwide. The extent of VAD in Zambian women of reproductive age is unknown owing to lack of survey inclusion or the use of static serum retinol concentrations, a low-sensitivity biomarker.

Objectives: This cross-sectional study employed isotopic techniques to determine VA status with serum and milk among women aged 18-49 y (n = 197) either lactating with infants aged 0-24 mo or nonlactating with or without infants.

Methods: Assistants were trained and piloted data collection. Demographic data, anthropometry, and relevant histories were obtained including malaria and anemia. For retinol isotope dilution (RID), baseline fasting blood and casual breast milk samples were collected before administration of 2.0 μmol 13C2-retinyl acetate and 24-h dietary recalls. On day 14, blood (n = 144) and milk (n = 66) were collected. Prevalence of total liver VA reserves (TLR) ≤0.10 μmol/g was defined as VAD with comparison to the DRI assumption of 0.07 μmol/g as minimally acceptable for North Americans.

Results: When a 20% adjustment for dose lost to milk was made in the RID equation for lactation, mean total body VA stores (TBS) for lactating women were 25% lower than for nonlactating women (P < 0.01), which was not the case without adjustment (P = 0.3). Mean ± SD TLR for all women were 0.15 ± 0.11 μmol/g liver. Using retinol purified from breast milk instead of serum for RID analysis yielded similar TBS and TLR, which were highly correlated between methods (P < 0.0001). Serum retinol ≤0.70 μmol/L had 0% sensitivity using either VAD liver cutoff and milk retinol ≤1.0 μmol/L had 42% sensitivity for VAD at 0.10 μmol/g.

Conclusions: Determining accurate VA status among women of reproductive age, especially lactating women, forms a basis for extrapolation to the general population and informing policy development and program implementation.
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http://dx.doi.org/10.1093/jn/nxaa320DOI Listing
January 2021

Distemper, extinction, and vaccination of the Amur tiger.

Proc Natl Acad Sci U S A 2020 12 23;117(50):31954-31962. Epub 2020 Nov 23.

Boyd Orr Centre for Population and Ecosystem Health, Institute of Biodiversity Animal Health and Comparative Medicine, University of Glasgow, Glasgow G12 8QQ, United Kingdom.

Canine distemper virus (CDV) has recently emerged as an extinction threat for the endangered Amur tiger (). CDV is vaccine-preventable, and control strategies could require vaccination of domestic dogs and/or wildlife populations. However, vaccination of endangered wildlife remains controversial, which has led to a focus on interventions in domestic dogs, often assumed to be the source of infection. Effective decision making requires an understanding of the true reservoir dynamics, which poses substantial challenges in remote areas with diverse host communities. We carried out serological, demographic, and phylogenetic studies of dog and wildlife populations in the Russian Far East to show that a number of wildlife species are more important than dogs, both in maintaining CDV and as sources of infection for tigers. Critically, therefore, because CDV circulates among multiple wildlife sources, dog vaccination alone would not be effective at protecting tigers. We show, however, that low-coverage vaccination of tigers themselves is feasible and would produce substantive reductions in extinction risks. Vaccination of endangered wildlife provides a valuable component of conservation strategies for endangered species.
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http://dx.doi.org/10.1073/pnas.2000153117DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7749280PMC
December 2020

Face Masks and the Cardiorespiratory Response to Physical Activity in Health and Disease.

Ann Am Thorac Soc 2021 03;18(3):399-407

Division of Pulmonary Medicine, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada; and.

To minimize transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the novel coronavirus responsible for coronavirus disease (COVID-19), the U.S. Centers for Disease Control and Prevention and the World Health Organization recommend wearing face masks in public. Some have expressed concern that these may affect the cardiopulmonary system by increasing the work of breathing, altering pulmonary gas exchange and increasing dyspnea, especially during physical activity. These concerns have been derived largely from studies evaluating devices intentionally designed to severely affect respiratory mechanics and gas exchange. We review the literature on the effects of various face masks and respirators on the respiratory system during physical activity using data from several models: cloth face coverings and surgical masks, N95 respirators, industrial respirators, and applied highly resistive or high-dead space respiratory loads. Overall, the available data suggest that although dyspnea may be increased and alter perceived effort with activity, the effects on work of breathing, blood gases, and other physiological parameters imposed by face masks during physical activity are small, often too small to be detected, even during very heavy exercise. There is no current evidence to support sex-based or age-based differences in the physiological responses to exercise while wearing a face mask. Although the available data suggest that negative effects of using cloth or surgical face masks during physical activity in healthy individuals are negligible and unlikely to impact exercise tolerance significantly, for some individuals with severe cardiopulmonary disease, any added resistance and/or minor changes in blood gases may evoke considerably more dyspnea and, thus, affect exercise capacity.
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http://dx.doi.org/10.1513/AnnalsATS.202008-990CMEDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7919154PMC
March 2021

Assisting target recognition through strong turbulence with the help of neural networks.

Appl Opt 2020 Oct;59(30):9434-9442

Imaging and target recognition through strong turbulence is regarded as one of the most challenging problems in modern turbulence research. As the aggregated turbulence distortion inevitably degrades remote targets and makes them less recognizable, both adaptive optics approaches and image correction methods will become less effective in retrieving correct attributes of the target. Meanwhile, machine learning (ML)-based algorithms have been proposed and studied using both hardware and software approaches to alleviate turbulence effects. In this work, we propose a straightforward approach that treats images with turbulence distortion as a data augmentation in the training set, and investigate the effectiveness of the ML-assisted recognition outcomes under different turbulence strengths. Retrospectively, we also apply the recognition outcomes to evaluate the turbulence strength through regression techniques. As a result, our study helps to build a deep connection between turbulence distortion and imaging effects through a standard perceptron neural network (NN), where mutual inference between turbulence levels and target recognition rates can be achieved.
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http://dx.doi.org/10.1364/AO.405663DOI Listing
October 2020

Optogenetic sleep enhancement improves fear-associated memory processing following trauma exposure in rats.

Sci Rep 2020 10 22;10(1):18025. Epub 2020 Oct 22.

Department of Biomedical Sciences, Pharmaceutical and Biomedical Sciences, WSU Health Sciences Spokane, Elson S. Floyd College of Medicine, Room 213/Lab 230, 412 E. Spokane Falls Blvd, Spokane, WA, 99202, USA.

Sleep disturbances are commonly found in trauma-exposed populations. Additionally, trauma exposure results in fear-associated memory impairments. Given the interactions of sleep with learning and memory, we hypothesized that increasing sleep duration following trauma exposure would restore overall function and improve trauma-induced fear-associated memory dysfunction. Here, we utilized single prolonged stress, a validated rodent model of post-traumatic stress disorder, in combination with optogenetic activation of hypothalamic melanin-concentrating hormone containing cells to increase sleep duration. The goal of this work was to ascertain if post-trauma sleep increases are sufficient to improve fear-associated memory function. In our laboratory, optogenetic stimulation after trauma exposure was sufficient to increase REM sleep duration during both the Light and Dark Phase, whereas NREM sleep duration was only increased during the Dark Phase of the circadian day. Interestingly though, animals that received optogenetic stimulation showed significantly improved fear-associated memory processing compared to non-stimulated controls. These results suggest that sleep therapeutics immediately following trauma exposure may be beneficial and that post-trauma sleep needs to be further examined in the context of the development of post-traumatic stress disorder.
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http://dx.doi.org/10.1038/s41598-020-75237-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7581760PMC
October 2020

Abnormal pulmonary perfusion heterogeneity in patients with Fontan circulation and pulmonary arterial hypertension.

J Physiol 2021 01 27;599(1):343-356. Epub 2020 Oct 27.

Department of Radiology, University of California, San Diego, CA, USA.

Key Points: The distribution of pulmonary perfusion is affected by gravity, vascular branching structure and active regulatory mechanisms, which may be disrupted by cardiopulmonary disease, but this is not well studied, particularly in rare conditions. We evaluated pulmonary perfusion in patients who had undergone Fontan procedure, patients with pulmonary arterial hypertension (PAH) and two groups of controls using a proton magnetic resonance imaging technique, arterial spin labelling to measure perfusion. Heterogeneity was assessed by the relative dispersion (SD/mean) and gravitational gradients. Gravitational gradients were similar between all groups, but heterogeneity was significantly increased in both patient groups compared to controls and persisted after removing contributions from large blood vessels and gravitational gradients. Patients with Fontan physiology and patients with PAH have increased pulmonary perfusion heterogeneity that is not explainable by differences in mean perfusion, gravitational gradients, or large vessel anatomy. This probably reflects vascular remodelling in PAH and possibly in Fontan physiology.

Abstract: Many factors affect the distribution of pulmonary perfusion, which may be disrupted by cardiopulmonary disease, but this is not well studied, particularly in rare conditions. An example is following the Fontan procedure, where pulmonary perfusion is passive, and heterogeneity may be increased because of the underlying pathophysiology leading to Fontan palliation, remodelling, or increased gravitational gradients from low flow. Another is pulmonary arterial hypertension (PAH), where gravitational gradients may be reduced secondary to high pressures, but remodelling may increase perfusion heterogeneity. We evaluated regional pulmonary perfusion in Fontan patients (n = 5), healthy young controls (Fontan control, n = 5), patients with PAH (n = 6) and healthy older controls (PAH control) using proton magnetic resonance imaging. Regional perfusion was measured using arterial spin labelling. Heterogeneity was assessed by the relative dispersion (SD/mean) and gravitational gradients. Mean perfusion was similar (Fontan = 2.50 ± 1.02 ml min  ml ; Fontan control = 3.09 ± 0.58, PAH = 3.63 ± 1.95; PAH control = 3.98 ± 0.91, P = 0.26), and the slopes of gravitational gradients were not different (Fontan = -0.23 ± 0.09 ml min  ml  cm ; Fontan control = -0.29 ± 0.23, PAH = -0.27 ± 0.09, PAH control = -0.25 ± 0.18, P = 0.91) between groups. Perfusion relative dispersion was greater in both Fontan and PAH than controls (Fontan = 1.46 ± 0.18; Fontan control = 0.99 ± 0.21, P = 0.005; PAH = 1.22 ± 0.27, PAH control = 0.91 ± 0.12, P = 0.02) but similar between patient groups (P = 0.13). These findings persisted after removing contributions from large blood vessels and gravitational gradients (all P < 0.05). We conclude that patients with Fontan physiology and PAH have increased pulmonary perfusion heterogeneity that is not explained by differences in mean perfusion, gravitational gradients, or large vessel anatomy. This probably reflects the effects of remodelling in PAH and possibly in Fontan physiology.
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http://dx.doi.org/10.1113/JP280348DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8315789PMC
January 2021

Evaluation of 1,1-cyclopropylidene as a thioether isostere in the 4-thio-thienopyrimidine (TTP) series of antimalarials.

Bioorg Med Chem 2020 11 11;28(22):115758. Epub 2020 Sep 11.

Department of Chemistry and Chemical Biology, Rutgers The State University of New Jersey, 610 Taylor Road, Piscataway, NJ 08854, USA.

The 4-(heteroarylthio)thieno[2,3-d]pyrimidine (TTP) series of antimalarials, represented by 1 and 17, potently inhibit proliferation of the 3D7 strain of P. falciparum (EC 70-100 nM), but suffer from oxidative metabolism. The 1,1-cyclopropylidene isosteres 6 and 16 were designed to obviate this drawback. They were prepared by a short route that features a combined Peterson methylenation / cyclopropanation transformation of, e. g., ketone 7. Isosteres 6 and 16 possess significantly attenuated antimalarial potency relative to parents 1 and 17. This outcome can be rationalized based on the increased out-of-plane steric demands of the latter two. In support of this hypothesis, the relatively flat ketone 7 retains some of the potency of 1, even though it appears to be a comparatively inferior mimic with respect to electronics and bond lengths and angles. We also demonstrate crystallographically and computationally an apparent increase in the strength of the intramolecular sulfur hole interaction of 1 upon protonation.
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http://dx.doi.org/10.1016/j.bmc.2020.115758DOI Listing
November 2020

Predicted Impact of COVID-19 on Neglected Tropical Disease Programs and the Opportunity for Innovation.

Clin Infect Dis 2021 04;72(8):1463-1466

Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Oxford, United Kingdom.

Due to the COVID-19 pandemic, many key neglected tropical disease (NTD) activities have been postponed. This hindrance comes at a time when the NTDs are progressing towards their ambitious goals for 2030. Mathematical modelling on several NTDs, namely gambiense sleeping sickness, lymphatic filariasis, onchocerciasis, schistosomiasis, soil-transmitted helminthiases (STH), trachoma, and visceral leishmaniasis, shows that the impact of this disruption will vary across the diseases. Programs face a risk of resurgence, which will be fastest in high-transmission areas. Furthermore, of the mass drug administration diseases, schistosomiasis, STH, and trachoma are likely to encounter faster resurgence. The case-finding diseases (gambiense sleeping sickness and visceral leishmaniasis) are likely to have fewer cases being detected but may face an increasing underlying rate of new infections. However, once programs are able to resume, there are ways to mitigate the impact and accelerate progress towards the 2030 goals.
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http://dx.doi.org/10.1093/cid/ciaa933DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7543306PMC
April 2021

Quadrant Fourier transform and its application in decoding OAM signals.

Opt Lett 2020 Aug;45(16):4428-4431

We present a new, to the best of our knowledge, concept of using quadrant Fourier transforms (QFTs) formed by microlens arrays (MLAs) to decode complex optical signals based on the optical intensity collected per quadrant area after the MLAs. From a computational optics viewpoint, we show the most promising use of the QFT in low-cost and passive decoding of laser signals carrying optical angular momenta (OAM) that are prevalent in research frontiers of optical communications, computation, and imaging. There are numerous ways of creating, adding, and combining OAM states in optical waves, while decoding or demultiplexing approaches often turn out to be complicated or expensive. The simple OAM decoder formed by a pair of identical MLAs, which are concatenated in the focal plane and transversely offset by half-pitch length, can accomplish the imaging task with four pixels per cell. By sorting the gradient curls of the optical wave into local quadrant cells, the decoder analyzes the intensity reallocation that is proportional to the gradients and computes the gradient curls accordingly. The low-cost, compactness, and simplicity of the proposed OAM sensor will further promote OAM-based applications, as well as many other applications that exploit the spatial complexity of optical signals.
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http://dx.doi.org/10.1364/OL.400642DOI Listing
August 2020

Effort Thrombosis Presenting as Unilateral "Pumped" Arm in a Climber.

Wilderness Environ Med 2020 Sep 6;31(3):344-349. Epub 2020 Aug 6.

Emergency Department, University of Colorado, Aurora, CO.

Upper extremity injuries are common among the growing population of climbers. Although conditions affecting musculoskeletal structures are the most common causes of symptoms, a comprehensive differential diagnosis is necessary to avoid the misdiagnosis of high-morbidity conditions in this patient population. We present a case of a climber with acute edema, erythema, and pain of the entire right upper extremity. After confirmation of an upper extremity deep vein thrombosis by ultrasound, and in the absence of secondary causes for his thrombotic process, he was diagnosed with effort thrombosis. The patient was treated acutely with anticoagulation, catheter thrombectomy, direct thrombolysis, and balloon angioplasty followed by surgical decompression of the subclavian vein. Owing to the importance of early diagnosis and initiation of treatment, it is critical to keep disorders affecting the upper thoracic vascular structures in consideration.
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http://dx.doi.org/10.1016/j.wem.2020.05.001DOI Listing
September 2020
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