bluuebunny/crossref_metadata_2025 huggingface dataset:
Time to SARS-CoV-2 PCR Clearance in Immunocompromising Conditions: Is Test-Based Removal From Isolation Necessary in Severely Immunocompromised Individuals?
Authors: Epstein Rachel L , Sperring Heather , Hofman Melissa , Lodi Sara , White Laura F , Barocas Joshua A , Bouton Tara C , Xiao Yian , Hsu Heather E , Miller Nancy S , Linas Benjamin P , Marathe Jai G
Published: May 2021

To determine the association between immunosuppression and time to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) polymerase chain reaction (PCR) clearance, we studied 3758 adults retested following initial SARS-CoV-2 infection. Cox proportional hazards models demonstrated delayed PCR clearance with older age, multiple comorbidities, and solid organ transplant but not by degree of immunocompromise. These findings challenge current retesting practices.
Current practices and policies regarding the use of high-flow nasal cannula on general pediatric inpatient wards in Canada
Authors: Novak Chris , Vomiero Gemma , de Caen Allan , Cooke Suzette
Published: May 2021

Objectives

High-flow nasal cannula (HFNC) oxygen therapy has become a common treatment for respiratory conditions in children. To our knowledge, no study has described practice patterns for HFNC on pediatric inpatient wards in Canada. The aim of this study was to survey current practices and policies regarding the use of HFNC on the ward in children’s hospitals in Canada.

Methods

We conducted a web-based survey of Pediatric Hospital Medicine section chiefs in major tertiary care hospitals in Canada. The primary outcome was the proportion of hospitals that use HFNC on the general pediatric ward. Secondary outcomes included indications for HFNC, initial and maximum flow rates, maximum FiO2, method of nutrition delivery while on HFNC, level of nursing and respiratory therapist care required, criteria for pediatric intensive care unit transfer, and subjective successes and challenges of implementing a ward-based HFNC policy.

Results

The section chief survey response rate was 100% (15/15). Eight centres (53%) allowed the use of HFNC outside of an intensive care setting. Six centres initiated HFNC on the ward, while two centres only accepted patients after HFNC had been initiated in an intensive care setting. Other practices and policies varied considerably from centre to centre.

Conclusion

Our study reveals that approximately half of tertiary children’s hospitals in Canada currently use HFNC on the ward and utilize a range of practices and policies. Other centres are considering implementation. Further research is needed to inform best practices for HFNC therapy, support stewardship of health care resources, and promote safe patient care.
AI based colorectal disease detection using real-time screening colonoscopy
Authors: Jiang Jiawei , Xie Qianrong , Cheng Zhuo , Cai Jianqiang , Xia Tian , Yang Hang , Yang Bo , Peng Hui , Bai Xuesong , Yan Mingque , Li Xue , Zhou Jun , Huang Xuan , Wang Liang , Long Haiyan , Wang Pingxi , Chu Yanpeng , Zeng Fan-Wei , Zhang Xiuqin , Wang Guangyu , Zeng Fanxin
Published: May 2021

Colonoscopy is an effective tool for early screening of colorectal diseases. However, the application of colonoscopy in distinguishing different intestinal diseases still faces great challenges of efficiency and accuracy. Here we constructed and evaluated a deep convolution neural network (CNN) model based on 117 055 images from 16 004 individuals, which achieved a high accuracy of 0.933 in the validation dataset in identifying patients with polyp, colitis, colorectal cancer (CRC) from normal. The proposed approach was further validated on multi-center real-time colonoscopy videos and images, which achieved accurate diagnostic performance on detecting colorectal diseases with high accuracy and precision to generalize across external validation datasets. The diagnostic performance of the model was further compared to the skilled endoscopists and the novices. In addition, our model has potential in diagnosis of adenomatous polyp and hyperplastic polyp with an area under the receiver operating characteristic curve of 0.975. Our proposed CNN models have potential in assisting clinicians in making clinical decisions with efficiency during application.
The role of auxin and sugar signaling in dominance inhibition of inflorescence growth by fruit load
Authors: Goetz Marc , Rabinovich Maia , Smith Harley M
Published: May 2021

Dominance inhibition of shoot growth by fruit load is a major factor that regulates shoot architecture and limits yield in agriculture and horticulture crops. In annual plants, the inhibition of inflorescence growth by fruit load occurs at a late stage of inflorescence development termed the end of flowering transition. Physiological studies show this transition is mediated by production and export of auxin from developing fruits in close proximity to the inflorescence apex. In the meristem, cessation of inflorescence growth is controlled in part by the age-dependent pathway, which regulates the timing of arrest. Here, we show the end of flowering transition is a two-step process in Arabidopsis (Arabidopsis thaliana). The first stage is characterized by a cessation of inflorescence growth, while immature fruit continues to develop. At this stage, dominance inhibition of inflorescence growth by fruit load is associated with a selective dampening of auxin transport in the apical region of the stem. Subsequently, an increase in auxin response in the vascular tissues of the apical stem where developing fruits are attached marks the second stage for the end of flowering transition. Similar to the vegetative and floral transition, the end of flowering transition is associated with a change in sugar signaling and metabolism in the inflorescence apex. Taken together, our results suggest that during the end of flowering transition, dominance inhibition of inflorescence shoot growth by fruit load is mediated by auxin and sugar signaling.
Recombinant CD300c-Ig fusion protein attenuates collagen-induced arthritis in mice
Authors: Liu Haiyan , Zhao Jin , Su Min , Tian Xiaohong , Lai Laijun
Published: May 2021

Objectives

RA is a chronic autoimmune disease characterized by joint inflammation and tissue destruction. Immune responses mediated by T cells and autoantibodies are known to play critical roles in RA. Collagen type II (CII)-induced arthritis (CIA) is a commonly used animal model of human RA. We have previously reported the identification of a new T cell inhibitory molecule CD300c. Here we investigate the ability of recombinant CD300c-IgG2a Fc (CD300c-Ig) fusion protein to prevent and treat CIA.

Methods

Mice were induced to develop CIA by CII and injected with CD300c-Ig or control Ig protein before or after CIA symptoms occur. The mice were examined for CIA clinical and pathological scores, and analysed for the expression of proinﬂammatory cytokines, the percentage and activation of CD4 T cells and regulatory T cells, CII-speciﬁc T cell proliferation and cytokine production, and CII-specific autoantibody production.

Results

In a prevention model, CD300c-Ig signiﬁcantly decreases CIA incidence, and reduces clinical and pathological arthritis scores. In the treatment model, CD300c-Ig ameliorates established CIA. The beneficial effects of CD300c-Ig are related to decreased expansion and activation of T cells in the spleen and reduced expression of proinﬂammatory cytokines in the joints. CD300c-Ig also inhibits CII-specific T cell proliferation and Th1 and Th17 cytokine production. In addition, CD300c-Ig treatment reduced the production of CII autoantibodies in the serum. Furthermore, CD300c-Ig inhibits the proliferation and activation of T cells from RA patients in vitro.

Conclusion

CD300c-Ig protein has the potential to be used in the treatment of patients with RA.
Investigating the Association Between Labour Epidural Analgesia and Postpartum Depression: A Prospective Cohort Study
Authors: Tan C.W. , Sultana R. , Kee M.Z.L. , Meaney M.J. , Sng B.L.
Published: May 2021

(Eur J Anaesthesiol. 2020;37:796–802)

Approximately 10-15% of women worldwide experience postpartum depression (PPD) following childbirth, which can lead to suicidal behaviors, infanticide, decreased maternal cognitive function and even increased behavioral problems in children. Given the incidence of and morbidity associated with PPD, recent efforts have focused on identifying modifiable risk factors that may contribute to the development of PPD. The primary aim of this study was to determine whether an association exists between the use of epidural analgesia (EA) during labor and the development of PPD.
Systematic Review of Simulated Airway Management Whilst Wearing Personal Protective Equipment
Authors: Sanfilippo F. , Tigano S. , Palumbo G.J. , Astuto M. , Murabito P.
Published: May 2021

(Br J Anaesth. 2020;125:e301–e305)

Tracheal intubation is required in approximately 2.3% of COVID-19 patients. As COVID-19 is highly transmissible, airway management is high-risk for healthcare workers. The use of full personal protective equipment (PPE) is common among published recommendations for reducing the risk of transmission to healthcare workers during intubation. Other common recommendations include using video laryngoscopy with a distant screen display, avoiding manual bag-mask ventilation and involving senior staff. These recommendations were based on experiences from present and past pandemics rather than controlled studies. This systematic review aimed to evaluate current best practices for airway management while using PPE by reviewing studies using manikin-based simulation.
Personal Protective Equipment, Airway Management, and Systematic Reviews. Comment on Br J Anaesth 2020; 125: e301e5
Authors: Sorbello M. , El-Boghdadly K. , Schumacher J. , Ahmad I.
Published: May 2021

(Br J Anaesth. 2020;125:e360–e361)

A recent paper by Sanilipo et al, studied simulated airway management while wearing personal protective equipment. There is a need to study this issue, as personal protective equipment (PPE) can cause discomfort and potentially make airway management more challenging. PPE may do this by impairing vision, limiting communication, restricting movement and limiting tactile sensitivity. However, there are some concerning aspects of this study itself.
Improved Outcomes With an Enhanced Recovery Approach to Cesarean Delivery
Authors: Mullman L. , Hilden P. , Goral J. , Gwacham N. , Tauro C. , Spinola K. , Rosales K. , Collier S. , Holmes L. , Maccione J , Pitera R. , Miller R. , Yodice P.
Published: May 2021

(Obstet Gynecol. 2020;136:685–691)

To improve the quality of perioperative care and facilitate patients’ quick recovery, a number of settings including gynecology have adopted enhanced recovery after surgery (ERAS) programs. These programs have been shown to have a positive impact on patients’ quality of care on hospital utilization measures. However, there is limited data on the effectiveness of ERAS programs in women undergoing cesarean delivery (CD) including reducing need for opioids. The aim of this study was to evaluate an ERAS program on outcomes in women undergoing cesarean delivery.
Extracorporeal Membrane Oxygenation in Pregnancy and the Postpartum Period: A Systematic Review of Case Reports
Authors: Ong J. , Zhang J.J.Y. , Lorusso R. , MacLaren G. , Ramanathana K.
Published: May 2021

(Int J Obstet Anesthesia. 2020;43:106–113)

Extracorporeal membrane oxygenation (ECMO) is a modified form of cardiopulmonary bypass used in intensive care units (ICU) in which venous blood is removed, pumped through an artificial oxygenating lung membrane and returned to the patient. Data on the use of ECMO in pregnant or postpartum patients is quite limited. This study explored the use of ECMO in pregnant and postpartum patients by reviewing published case studies and analyzing maternal and neonatal outcomes.
Identification of Factors Associated With Delayed Treatment of Obstetric Hypertensive Emergencies
Authors: Kantorowska A. , Heiselman C.J. , Halpern T.A. , Akerman M.B. , Elsayad A. , Muscat J.C. , Sicuranza G.B. , Vintzileos A.M. , Heo H.J.
Published: May 2021

(Am J Obstet Gynecol. 2020;223:250.e1–11)

Approximately 10% of all pregnancies worldwide are complicated by hypertensive disorders. The most serious of the hypertensive spectrum includes hypertensive emergencies, which can be fatal. Criteria of a hypertensive emergency includes persistent (>15 min duration), acute-onset, with systolic blood pressure of greater than or equal to 160 mm Hg, and diastolic blood pressure of greater than or equal to 110 mm Hg. Obstetric hypertensive emergencies must be treated expeditiously to reduce risks of maternal morbidity or death. The American College of Obstetricians and Gynecologists recommends treatment of hypertensive emergencies within 30-60 minutes of symptom onset in order to reduce risk of maternal stroke. The objective of this study was to identify factors associated with delayed treatments and to determine the timely treatment rate for hypertensive emergencies.
Maternal Cardiac Function in Women at High Risk for Pre-eclampsia Treated With 150 mg Aspirin or Placebo: An Observational Study
Authors: Ling H.Z. , Jara P.G. , Bisquera A. , Poon L.C. , Nicolaides K.H. , Kametas N.A.
Published: May 2021

(BJOG. 2020;127:1018–1025)

The Aspirin for Prevention of Preterm Pre-eclampsia (ASPRE) trial recently reported that aspirin (150 mg/d) may reduce the risk of preterm and early pre-eclampsia (PE) by 60% and 90%, respectively, in pregnant women screened in their first trimester. Although commonly used for the prevention and treatment of heart attacks or strokes in the general population, aspirin has also been shown to cause high blood pressure and exacerbate pre-existing heart failure. This may be explained in part by the inhibition of PGI2, a compensatory vasodilatory prostacyclin which results in vasoconstriction. In pregnant women at high risk for preterm PE, aspirin could lead to unfavorable cardiac outcomes. The aim of this study was to compare the hemodynamic effect of aspirin versus placebo in women at high-risk for preterm PE and to compare this effect in women at low risk versus high risk for developing this condition.
Effect of Cord Milking in Late Preterm Infants and Full-term Infants: A Systematic Review and Meta-analysis
Authors: Ortiz-Esquinas I. , Rodríguez-Almagro J. , Gómez-Salgado J. , Arias-Arias A. , Ballesta-Castillejos A. , Hernández-Martínez A.
Published: May 2021

(Birth. 2020;47:259–269)

Delayed cord clamping (DCC) is associated with many benefits for neonates including higher neonatal hemoglobin and additional iron stores, but it is not always feasible. Umbilical cord milking (UCM) can be an alternative. The use of UCM has been found to be beneficial in premature infants in one meta-analysis, but there was not enough data to suggest benefits to full-term infants. Another review found most studies showed full-term and late-preterm infants benefited from UCM or DCC compared to immediate cord clamping. This study aimed to evaluate the effects of UCM for full-term and late-preterm infants and stratify the results by gestational age and method.
Preterm Delivery and Long-Term Mortality in Women: National Cohort and Co-sibling Study
Authors: Crump C. , Sundquist J. , Sundquist K.
Published: May 2021

(BMJ. 2020;370:m2533)

Preterm birth has been associated with numerous health risks to both the mother and child. Women who deliver prematurely (gestational age of <37 wk) may have increased risk of heart disease and other cardiometabolic disorders later in life. Yet, information on the long-term impact of premature delivery on mortality and the ultimate underlying causes of death is limited. The aim of this study was to determine the association between preterm delivery and the long-term mortality risk among women who deliver prematurely.
Exome Sequencing for Prenatal Diagnosis in Nonimmune Hydrops Fetalis
Authors: Sparks T.N. , Lianoglou B.R. , Adami R.R. , Pluym I.D. , Holliman K. , Duffy K. , Downum S.L. , Patel S. , Faubel A. , Boe N.M. , Field N.T. , Murphy A. , Laurent L.C. , Jolley J. , Uy C. , Slavotinek A.M. , Devine P. , Hodoglugil U. , Van Ziffle J. , Sanders S.J. , MacKenzie T.C. , Norton M.E.
Published: May 2021

(N Engl J Med. 2020;383:1746–1756)

Nonimmune hydrops fetalis (NIHF) is a severe disorder associated with a high risk of stillbirth, preterm birth, neonatal death, and neonatal complications. NIHF is a shared presentation of a number of genetic disorders. Using standard genetic testing with karyotyping or chromosomal microarray, the cause of NIHF can be determined in only 25% of cases. Single-gene disorders may substantially contribute to NIHF, but this is not yet clear. This study aimed to explore the use of exome sequencing for diagnosing single-gene disorders in unexplained NIHF cases and establish the diagnostic yield of exome sequencing.
Nonimmune Hydrops Fetalis — More Than Meets the Eye?
Authors: Kilby M.D.
Published: May 2021

(N Engl J Med. 2020;383:1785–1786)

Nonimmune Hydrops Fetalis (NIHF) is typically defined as fetal fluid accumulation in two sites and affects up to 1 in 1,700 fetuses. There are multiple causes, including chromosomal abnormalities and structural malformations. Perinatal mortality is high in pregnancies where NIHF is present in the first trimester. In two different studies, diagnostic variants were identified in 9% and 24% of fetuses with NIHF using exome sequencing.
An Obstetric Anaesthetist a Key to Successful Conversion of Epidural Analgesia to Surgical Anaesthesia for Caesarean Delivery?
Authors: Bjornestad E.E. , Haney M.F.
Published: May 2021

(Acta Anaesthesiol Scand. 2020;64:142–144)

A recent report by Wagner et al explores whether the presence of an obstetric anesthetist influences the mode of anesthesia in emergency cesarean delivery. General anesthesia used in cesarean delivery is associated with risks, while epidural anesthesia should only be used in cases when labor analgesia has been established. Using regional anesthesia to avoid general anesthesia in emergency cesarean deliveries may decrease the risk of hypoxia and unwanted intraoperative awareness, and may decrease postoperative pain. The Royal College of Anesthetists suggest an acceptable rate of less than 3% for general anesthesia in patients receiving labor epidural analgesia.
2020 Neonatal Nurse Practitioner Workforce Survey
Authors: Snapp Barbara , Moore Tiffany A. , Wallman Carol , Staebler Suzanne
Published: May 2021

Background:

The National Association of Neonatal Nurse Practitioners (NANNP) partnered with the National Certification Corporation (NCC) to invite all NCC-certified neonatal nurse practitioners (NNPs) to participate in a national survey on NNP compensation, workforce environment, and satisfaction measures.

Purpose:

To understand the current NNP compensation, benefits, and workforce environment.

Methods:

An anonymous survey was sent to 6558 board-certified NNPs with 845 respondents.

Results:

Most of the survey respondents (92%) are in direct patient care (n = 804) with 83% (n=703) working full time (35 hours or more). Those NNPs with less than 5 years' experience had a mean salary of $119,000 per year while more experienced NNPs (30-plus years) earned a mean salary of $134,000 per year. Half of the NNPs (51%) report high satisfaction with their scope of practice and role in their organization. Distribution of NNPs throughout the workforce is suboptimal, with 67% of the administrators indicating they do not have enough NNPs.

Implications for Practice and Research:

The 2020 NANNP workforce survey collected information on NNP compensation, benefits, work environment, and experiences. It identified areas of satisfaction, such as compensation with bonuses and pay increases, and acknowledged areas needing improvement such as the lack of diversity within the profession. Utilizing the results of the survey will help create a more diverse, well-educated, and informed workforce to ensure culturally competent NNPs remain relevant within the healthcare system.
A Guide to Upper Gastrointestinal Tract, Biliary, and Pancreatic Disorders
Authors: Abushamma Suha , Early Dayna S.
Published: May 2021

This monograph provides an overview of pathophysiology and screening, followed by sections on diagnosis and management of upper gastrointestinal, biliary, and pancreatic disorders. The most common upper gastrointestinal disorder is GERD, which affects women of all ages and creates a treatment challenge in pregnant women. Gallstone disease is the most common biliary disorder. A case-based format is used to review management of gallstone disease in pregnancy, as well as chronic pancreatitis in pregnancy. Some of these disorders can be treated by obstetrician–gynecologists; however, many require additional testing and treatment in consultation with a gastroenterologist.
A review on the most important viruses in oral cavity cancers
Authors: Jalilian Reza , Amiri Human , Mehraban Saeed Hasani , Asadi Amir Ali
Published: May 2021

Introduction:

Oral cancer is the sixth common malignancy worldwide. Squamous cell carcinoma (SCC) accounts for 90% of the oral cancers and is the 11th common cancer. Various studies showed that HPV, EBV and some other viruses might be the cause for a group of head and neck cancers including oral cavity cancer (OCC). The aim of this study was to assess the important viral infection, in the induction of oral cavity cancers.

Method:

Data was collected using key words including oral cavity, cancer, malignancy, OCC, OSCC, virus, infection, HPV, EBV, HCV in international databases including PubMed, Web of Science, Scopus, Cochrane and Embase until 2020.

Result:

A total of 30 original articles were reviewed after eliminating unrelated and redundant articles. The results of all reviewed articles except four indicated that the role of viral infections in OCC. Yen and Prathyusha reported that the prevalence of EBV among OCC cases ranged from 20 to 80%. The rate of HPV infection in patient with OCC ranged from 1.9% in the study by Smith et al. to 51.5 in the study by Tachezy et al.

Conclusion:

Review of epidemiological studies revealed that HPV and EBV infection were significantly related to OCC, whereas the relationship between OCC and HCV was less prominent. Therefore, the high prevalence of these viral infections can be considered as a possible reason for the incidence of OCC. further studies are required to identify the exact mechanism for the carcinogenesis of these viruses.
Quantifying the Effect of Topical Nitroglycerin on Random Pattern Flap Perfusion in a Rodent Model: An Application of the ViOptix Intra.Ox for Dynamic Flap Perfusion Assessment and Salvage
Authors: Khavanin Nima , Yesantharao Pooja , Kraenzlin Franca , Darrach Halley , Sacks Justin M.
Published: May 2021

Background:

Near-infrared spectroscopy can detect changes in tissue oxygenation postoperatively that predict flap necrosis. The authors hypothesized that this technology can be applied along with topical nitroglycerin to measure an improvement in tissue oxygenation that correlates with tissue salvage.

Methods:

Dorsal, random pattern flaps measuring 10 × 3 cm were raised using Sprague-Dawley rats. Tissue oxygenation was measured after flap elevation in 10 locations using the ViOptix Intra.Ox. Animals were divided into three groups that received 30 mg of topical nitroglycerin daily, twice-daily, or not at all. Oxygenation measurements were repeated on postoperative day 1 and animals were euthanized on day 7 and evaluated for tissue necrosis.

Results:

Tissue necrosis was greatest in controls (51.3 mm) compared to daily (28.8 mm) and twice-daily nitroglycerin (18.8 mm; p = 0.035). Three flap perfusion zones were identified: healthy (proximal, 50 mm), necrotic (distal, 20 mm), and watershed. Immediate postoperative tissue oxygenation was highest in healthy tissue (57.2 percent) and decreased to 33.0 and 19.3 percent in the watershed and necrotic zones, respectively (p < 0.001). One day after treatment with nitroglycerin, oxygenation in the healthy zone did not increase significantly (mean difference, −1.5 percent). The watershed (17.8 percent; p < 0.001) and necrotic zones (16.3 percent; p <0.001) did exhibit significant improvements that were greater than those measured in control tissues (7.9 percent; both p < 0.001).

Conclusions:

Serial perfusion assessment using the ViOptix Intra.Ox measured a significant improvement in flap oxygenation after treatment with topical nitroglycerin. Within the watershed area of the flap, this increase in tissue oxygenation was associated with the salvage of ischemic tissue.
Cross-cultural Comparison of Perceptions and Knowledge About Electroconvulsive Therapy Among Adults Who Screened Positive for Depression in the United States, India, and China
Authors: Tsai Jack , Huang Minda , He Hongbo , Selek Salih , Rosenheck Robert A.
Published: May 2021

Objective

Despite the established efficacy of electroconvulsive therapy (ECT), negative perceptions and inaccurate knowledge about ECT in the United States and other countries persist. This study examined ECT perceptions and knowledge in the 3 most populous countries in the world.

Methods

We recruited participants who screened positive for depression on the Patient Health Questionnaire 9 (PHQ-9) in the United States (n = 1643), India (n = 1469), and China (n = 328) and compared responses on the ECT–Perception and Knowledge Scale.

Results

Although the US sample had significantly higher PHQ-9 scores than the India and China samples, the US sample was less likely to have been offered ECT or to have ever received ECT. Moreover, the US sample scored lower on the ECT Perception and Knowledge subscales than the other samples indicating more negative perceptions and inaccurate knowledge about ECT. Across samples, there were moderate fears about ECT being painful or causing brain damage, and misconceptions about ECT being outdated and adverse effects of induced seizures. Higher PHQ-9 scores were correlated with more negative perceptions.

Conclusions

Greater public education is needed about ECT, particularly in the United States. Misperceptions and lack of knowledge may hinder utilization of ECT in India, China, and the United States.
Patterns and Progress of Peninsular Malaysia’s Amphibian Research in the 21st Century (2000–2020)
Authors: Chan Kin Onn , Ahmad Norhayati
Published: May 2021

In this study, we review the status, patterns, and progress of Peninsular Malaysia’s amphibian research in the 21st century with the main goal of identifying areas for improvement that can help focus and prioritize future research initiatives. Between 2000–2020 we found 130 publications that can be broadly categorized into four groups: 1) checklists and biodiversity; 2) new species and taxonomy; 3) ecology and natural history; and 4) evolution and phylogenetics. An average of 6.5 papers was published per year and although the number of papers fluctuated, there was a significant upward trend in the number of papers published. Almost half (49%) of all papers published comprised checklists and biodiversity-related papers. This was followed by new species and taxonomy (25%, 33 papers), evolution and phylogenetics (14%, 18 papers), and ecology and natural history (12%, 16 papers). Amphibian research was conducted most frequently in the states of Kedah, Pahang, and Perak, and most infrequently in the states of Malacca, Negeri Sembilan, Selangor/Kuala Lumpur, Perlis, and Kelantan. Despite being a megadiverse country and a biodiversity hotspot, not a single conservation-centric paper has ever been published on Peninsular Malaysian amphibians, highlighting the urgent need for future research to focus on conservation.
Novel application of capture-recapture methods to estimate the completeness of contact tracing during a large outbreak of Ebola Virus Disease, Democratic Republic of Congo, 2018-2020
Authors: Polonsky Jonathan A. , Böhning Dankmar , Keita Mory , Ahuka-Mundeke Steve , Nsio-Mbeta Justus , Abedi Aaron Aruna , Mossoko Mathias , Estill Janne , Keiser Olivia , Kaiser Laurent , Yoti Zabulon , Sangnawakij Patarawan , Lerdsuwansri Rattana , Rio Vilas Victor J. Del
Published: May 2021

Despite its critical role in containing outbreaks, the efficacy of contact tracing (CT), measured as the sensitivity of case detection, remains an elusive metric. We estimated the sensitivity of CT by applying unilist capture-recapture methods on data from the 2018-2020 outbreak of Ebola virus disease in the Democratic Republic of Congo. We applied different distributional assumptions to the zero-truncated count data to estimate the number of unobserved cases with a) any contacts and b) infected contacts, to compute CT sensitivity. Geometric distributions were the best fitting models. Our results indicate that CT efforts identified almost all (n=792, 99%) of the cases with any contacts, but only half (n=207, 48%) of the cases with infected contacts, suggesting that CT efforts performed well at identifying contacts during the listing stage, but performed poorly during the contact follow-up stage. We discuss extensions to our work and potential applications for the current COVID-19 pandemic.
Ultrafast amplitude modulation for molecular and hemodynamic ultrasound imaging
Authors: Rabut Claire , Wu Di , Ling Bill , Jin Zhiyang , Malounda Dina , Shapiro Mikhail G.
Published: May 2021

Ultrasound is playing an emerging role in molecular and cellular imaging thanks to new micro- and nanoscale contrast agents and reporter genes. Acoustic methods for the selective in vivo detection of these imaging agents are needed to maximize their impact in biology and medicine. Existing ultrasound pulse sequences use the nonlinearity in contrast agents’ response to acoustic pressure to distinguish them from mostly linear tissue scattering. However, such pulse sequences typically scan the sample using focused transmissions, resulting in a limited frame rate and restricted field of view. Meanwhile, existing wide-field scanning techniques based on plane wave transmissions suffer from limited sensitivity or nonlinear artifacts. To overcome these limitations, we introduce an ultrafast nonlinear imaging modality combining amplitude-modulated pulses, multiplane wave transmissions and selective coherent compounding. This technique achieves contrast imaging sensitivity comparable to much slower gold-standard amplitude modulation sequences and enables the acquisition of larger and deeper fields of view, while providing a much faster imaging framerate of 3.2kHz. Additionally, it enables simultaneous nonlinear and linear image formation, and allows concurrent monitoring of phenomena accessible only at ultrafast framerates, such as blood volume variations. We demonstrate the performance of this ultrafast amplitude modulation (uAM) technique by imaging gas vesicles, an emerging class of genetically encodable biomolecular contrast agents, in several in vitro and in vivo contexts. These demonstrations include the rapid discrimination of moving contrast agents and the real-time monitoring of phagolysosomal function in the mouse liver.
Generative adversarial neural networks maintain decoder accuracy during signal disruption in simulated long-term recordings from brain computer interfaces
Authors: Stephens Thomas , Cafaro Jon , MacRae Ryan , Simons Stephen
Published: May 2021

Chronically implanted brain-computer interfaces (BCIs) provide amazing opportunities to those living with disability and for the treatment of chronic disorders of the nervous system. However, this potential has yet to be fully realized in part due to the lack of stability in measured signals over time. Signal disruption stems from multiple sources including mechanical failure of the interface, changes in neuron health, and glial encapsulation of the electrodes that alter the impedance. In this study we present an algorithmic solution to the problem of long-term signal disruption in chronically implanted neural interfaces. Our approach utilizes a generative adversarial network (GAN), based on the original Unsupervised Image to Image Translation (UNIT) algorithm, which learns how to recover degraded signals back to their analogous non-disrupted (“clean”) exemplars measured at the time of implant. We demonstrate that this approach can reliably recover simulated signals in two types of commonly used neural interfaces: multi-electrode arrays (MEA), and electrocorticography (ECoG). To test the accuracy of signal recovery we employ a common BCI paradigm wherein a classification algorithm (neural decoder) is trained on the starting (non-disrupted) set of signals. Performance of the decoder demonstrates expected failure over time as the signal disruption accumulates. In simulated MEA experiments, our approach recovers decoder accuracy to >90% when as many as 13/ 32 channels are lost, or as many as 28/32 channels have their neural responses altered. In simulated ECoG experiments, our approach shows stabilization of the neural decoder indefinitely with decoder accuracies >95% over simulated lifetimes of over 1 year. Our results suggest that these types of neural networks can provide a useful tool to improve the long-term utility of chronically implanted neural interfaces.
Differential Activity-Dependent Increase in Synaptic Inhibition and Parvalbumin Interneuron Recruitment in Dentate Granule Cells and Semilunar Granule Cells
Authors: Afrasiabi Milad , Gupta Akshay , Xu Huaying , Swietek Bogumila , Santhakumar Vijayalakshmi
Published: May 2021

Strong inhibitory synaptic gating of dentate gyrus granule cells (GCs), attributed largely to fast-spiking parvalbumin interneurons (PV-INs), is essential to maintain sparse network activity needed for dentate dependent behaviors. However, the contribution of PV-INs to basal and input driven sustained synaptic inhibition in GCs and semilunar granule cells (SGCs), a sparse morphologically distinct dentate projection neuron subtype are currently unknown. In studies conducted in hippocampal slices from mice, we find that although basal inhibitory postsynaptic currents (IPSCs) are more frequent in SGCs and optical activation of PV-INs elicited IPSCs in both GCs and SGCs, optical suppression of PV-INs failed to reduce IPSC frequency in either cell type. Amplitude and kinetics of IPSCs evoked by perforant path activation were not different between GCs and SGCs. However, the robust increase in sustained polysynaptic IPSCs elicited by paired afferent stimulation was lower in SGCs than in simultaneously recorded GCs. Optical suppression of PV-IN selectively reduced sustained IPSCs in SGCs but not in GCs. These results demonstrate that PV-INs, while contributing minimally to basal synaptic inhibition in both GCs and SGCs in slices, mediate sustained feedback inhibition selectively in SGCs. The temporally selective blunting of activity-driven sustained inhibitory gating of SGCs could support their preferential and persistent recruitment during behavioral tasks.

Significance Statement

Our study identifies that feedback inhibitory regulation of dentate semilunar granule cells, a sparse and functionally distinct class of projection neurons, differs from that of the classical projection neurons, granule cells. Notably, we demonstrate relatively lower activity dependent increase in sustained feedback inhibitory synaptic inputs to semilunar granule cells when compared to granule cells which would facilitate their persistent activity and preferential recruitment as part of memory ensembles. Since dentate granule cell activity levels during memory processing are heavily shaped by basal and feedback inhibition, the fundamental differences in basal and evoked sustained inhibition between semilunar granule cells and granule cells characterized here provide a framework to reorganize current understanding of the dentate circuit processing.
Patients with presumed tuberculosis in sub-Saharan Africa that are not diagnosed with tuberculosis: a systematic review and meta-analysis
Authors: Jayasooriya S , Dimambro-Denson F , Beecroft C , Balen J , Awokola B , Mitchell C , Kampmann B , Campbell F , Dodd PJ , Mortimer K
Published: May 2021

Background

Many patients in sub-Saharan Africa whom a diagnosis of tuberculosis is considered are subsequently not diagnosed with tuberculosis. The proportion of patients this represents, and their alternative diagnoses, have not previously been systematically reviewed.

Methods

We searched four databases from inception to April 27, 2020, without language restrictions (PROSPERO: CRD42018100004). We included all adult pulmonary tuberculosis diagnostic studies from sub-Saharan Africa, excluding case series and inpatient studies. We extracted the proportion of patients with presumed tuberculosis subsequently not diagnosed with tuberculosis and any alternative diagnoses received. We conducted a random-effects meta-analysis to obtain pooled estimates stratified by passive and active case finding.

Results

Our search identified 1799 studies, of which 18 studies with 14527 participants from 10 African countries were included. The proportion of patients with presumed tuberculosis subsequently not diagnosed with tuberculosis was 48.5% (95% CI 38.4-56.7) in passive and 92.7% (95% CI 83.1-97.0) in active case finding studies. This proportion increased with declining numbers of clinically diagnosed tuberculosis cases. Past history of tuberculosis was documented in only 55% of studies, with just five out of 18 reporting any alternative diagnoses.

Discussion

Nearly half of all patients with presumed tuberculosis in sub-Saharan Africa do not have a final diagnosis of active tuberculosis. This proportion may be higher when active case finding strategies are used. Little is known about the healthcare needs of these patients. Research is required to better characterise these patient populations and plan health system solutions that meet their needs.

Funding

NIHR, UK MRC
A new type of ERGIC-ERES membrane contact mediated by TMED9 and SEC12 is required for autophagosome biogenesis
Authors: Li Shulin , Yan Rui , Xu Jialu , Zhao Shiqun , Ma Xinyu , Sun Qiming , Zhang Min , Li Ying , Liu Jun-Jie Gogo , Chen Liangyi , Li Sai , Xu Ke , Ge Liang
Published: May 2021

Under stress, the endomembrane system undergoes reorganization to support autophagosome biogenesis, which is a central step in autophagy. How the endomembrane system remodels has been poorly understood. Here we identify a new type of membrane contact formed between the ER-Golgi intermediate compartment (ERGIC) and the ER-exit site (ERES) in the ER-Golgi system, which is essential for promoting autophagosome biogenesis induced by different stress stimuli. The ERGIC-ERES contact is established by the interaction between TMED9 and SEC12 which generates a short distance opposition (as close as 2-5 nm) between the two compartments. The tight membrane contact allows the ERES-located SEC12 to transactivate COPII assembly on the ERGIC. In addition, a portion of SEC12 also relocates to the ERGIC. Through both mechanisms, the ERGIC-ERES contact promotes formation of the ERGIC-derived COPII vesicle, a membrane precursor of the autophagosome. The ERGIC-ERES contact is physically and functionally different from the TFG-mediated ERGIC-ERES adjunction involved in secretory protein transport, and therefore defines a unique endomembrane structure generated upon stress conditions for autophagic membrane formation.
Centrosome maturation requires phosphorylation-mediated sequential domain interactions of SPD-5
Authors: Nakajo Momoe , Kano Hikaru , Tsuyama Kenji , Haruta Nami , Sugimoto Asako
Published: May 2021

Centrosomes consist of two centrioles and surrounding pericentriolar material (PCM). PCM expands during mitosis in a process called centrosome maturation, in which PCM scaffold proteins play pivotal roles to recruit other centrosomal proteins. In C. elegans, the scaffold protein SPD-5 forms PCM scaffold in a PLK-1 phosphorylation-dependent manner. However, how phosphorylation of SPD-5 promotes PCM scaffold assembly is unclear. Here, we identified three functional domains of SPD-5 through in vivo domain analyses, and propose that sequential domain interactions of SPD-5 are required for mitotic PCM scaffold assembly. Firstly, SPD-5 is targeted to centrioles through direct interaction between its centriole localization (CL) domain and a centriolar protein PCMD-1. Then, intra- and inter-molecular interaction between SPD-5 phospho-regulated multimerization (PReM) domain and the PReM association (PA) domain is triggered by phosphorylation by PLK-1, which leads to PCM scaffold expansion. Our findings suggest that the sequential domain interactions of scaffold proteins mediated by Polo/PLK-1 phosphorylation is an evolutionarily conserved mechanism of PCM scaffold assembly.
Small RNAs guide histone methylation in Arabidopsis embryos
Authors: Parent Jean-Sébastien , Cahn Jonathan , Herridge Rowan P. , Grimanelli Daniel , Martienssen Robert A.
Published: May 2021

Epigenetic reprogramming occurs during gametogenesis as well as during embryogenesis to reset the genome for early development. In flowering plants, many heterochromatic marks are maintained in sperm, but asymmetric DNA methylation is mostly lost. Asymmetric DNA methylation is dependent on small RNA but the re-establishment of silencing in embryo is not well understood. Here we demonstrate that small RNAs direct the histone H3 lysine 9 dimethylation during Arabidopsis thaliana embryonic development, together with asymmetric DNA methylation. This de novo silencing mechanism depends on the catalytic domain of SUVH9, a Su(Var)3-9 homolog thought to be catalytically inactive.
Hydrogen-bond directionality and symmetry in [C(O)NH](N)2P(O)-based structures: a comparison between X-ray crystallography data and neutron-normalized values, and evaluation of reliability
Authors: Taherzadeh Maryam , Pourayoubi Mehrdad , Vahdani Alviri Banafsheh , Shoghpour Bayraq Samad , Ariani Maral , Nečas Marek , Dušek Michal , Eigner Václav , Amiri Rudbari Hadi , Bruno Giuseppe , Mancilla Percino Teresa , Leyva-Ramírez Marco A. , Damodaran Krishnan
Published: May 2021

For [C(O)NH](N)2P(O)-based structures, the magnitude of the differences in the N—H...O, H...O=P and H...O=C angles has been evaluated when the N—H bond lengths, determined by X-ray diffraction, were compared to the neutron normalized values and the maximum percentage difference was obtained,i.e.about 3% for the angle even if the N—H bond lengths have a difference of about 30% (0.7 Å for the X-ray and 1.03 Å for the neutron-normalized value). The symmetries of the crystals are discussed with respect to the symmetry of the molecules, as well as to the symmetry of hydrogen-bonded motifs, and the role of the most directional hydrogen bond in raising the probability of obtaining centrosymmetric crystal structures is investigated. The work was performed by considering nine new X-ray crystal structures and 204 analogous structures retrieved from the Cambridge Structural Database.
Thermal expansion and phase transformation in the rare earth di-titanate (R2Ti2O7) system
Authors: Hulbert Benjamin S. , McCormack Scott J. , Tseng Kuo-Pin , Kriven Waltraud M.
Published: May 2021

Characterization of the thermal expansion in the rare earth di-titanates is important for their use in high-temperature structural and dielectric applications. Powder samples of the rare earth di-titanatesR2Ti2O7(orR2O3·2TiO2), whereR= La, Pr, Nd, Sm, Gd, Dy, Er, Yb, Y, which crystallize in either the monoclinic or cubic phases, were synthesized for the first time by the solution-based steric entrapment method. The three-dimensional thermal expansions of these polycrystalline powder samples were measured byin situsynchrotron powder diffraction from 25°C to 1600°C in air, nearly 600°C higher than otherin situthermal expansion studies. The high temperatures in synchrotron experiments were achieved with a quadrupole lamp furnace. Neutron powder diffraction measured the monoclinic phases from 25°C to 1150°C. The La2Ti2O7member of the rare earth di-titanates undergoes a monoclinic to orthorhombic displacive transition on heating, as shown by synchrotron diffraction in air at 885°C (864°C–904°C) and neutron diffraction at 874°C (841°C–894°C).
The strategic choice of contract types in business process outsourcing
Authors: Ge Ling , Wang Xiaoyan , Yang Zhilin
Published: May 2021

Purpose

How to determine the appropriate contractual structure for an outsourcing relationship has been a major theme in the business process outsourcing (BPO) literature. Drawing on transaction cost economics, this study aims to examine how anticipated coordination and adaptation costs in a BPO relationship affect the choice of contract types. Specifically, this research categorizes contracts types (fixed-price, time and materials and hybrid contracts) based on levels of contract design comprehensiveness and flexibility to change.

Design/methodology/approach

The research setting is the BPO for a focal firm, involving a contractor. Data from 153 US companies are collected using a structured questionnaire on senior executives of functional areas of marketing, IT and finance. Hypotheses were tested using ordered probit model.

Findings

The results show that maturity is negatively associated with anticipated adaptation costs, while modularity and IT detachability are negatively related to anticipated coordination costs. Furthermore, adaptation costs have a direct impact on the choice, whereas the anticipated coordination costs do not have a significant direct impact on contract choice. The strength of adaptation costs' impact, however, is significantly reduced when coordination costs are high.

Originality/value

This study explicitly examines the role of anticipated coordination and adaptation costs in shaping the strategic choice of contract types in the BPO market. By differentiating the two types of anticipated transaction costs, this research enables a better understanding of the dynamics between transaction characteristics, anticipated transaction costs and contract types in complicated relationships such as BPO relationships.
Continuance intention in running apps: the moderating effect of relationship norms
Authors: Cheng Li Keng , Huang Hsien-Long , Lai Ching-Chi
Published: May 2021

Purpose

The number of people using running apps has increased. Accordingly, a growing number of sports brands are launching running apps in hopes of improving their connection with consumers and thereby enhancing consumers' brand preference and purchase intention. This study adopted an integrated perspective to explore the effects of perceived usefulness, perceived ease of use and self-expression on consumers' continued use of running apps.

Design/methodology/approach

Convenience sampling was conducted among consumers in Taiwan (n = 251). Structural equation modeling using AMOS 21 was performed to analyze the data.

Findings

The study results revealed that (1) users' perceived usefulness, perceived ease of use and self-expression significantly positively affected continuance intention, and (2) continuance intention was significantly positively correlated with word-of-mouth (WOM) and brand intimacy. Furthermore, the study confirmed the moderating effect of consumers' relationship norms on the correlation between continuance intention and WOM and brand intimacy.

Originality/value

Amid the increasing emphasis on self-expression, almost all running apps endeavor to enable users to share their achievements, such as accumulated mileage and routes. However, research has rarely focused on whether these features influence consumers' continued use of running apps and whether these influences in turn affect consumers’ attitudes toward a brand. Therefore, this study explored the effect of self-expression on the continued use of running apps.