The 2021 SIIM-FISABIO-RSNA Machine Learning COVID-19 Challenge: Annotation and Standard Exam Classification of COVID-19 Chest Radiographs.

We describe the curation, annotation methodology, and characteristics of the dataset used in an artificial intelligence challenge for detection and localization of COVID-19 on chest radiographs. The chest radiographs were annotated by an international group of radiologists into four mutually exclusive categories, including "typical," "indeterminate," and "atypical appearance" for COVID-19, or "negative for pneumonia," adapted from previously published guidelines, and bounding boxes were placed on airspace opacities. This dataset and respective annotations are available to researchers for academic and noncommercial use.

L-lactic acidosis: pathophysiology, classification, and causes; emphasis on biochemical and metabolic basis.

L-lactic acidosis (L-LA) is the most common cause of metabolic acidosis in the critical care setting, which has been associated with a large increase in mortality. The purpose of this article is to provide clinicians with an overview of the biochemical and metabolic background required to understand the different pathophysiological mechanisms that may lead to the development of L-LA. We propose a classification based on whether the pathophysiology of L-LA is due predominantly to increased production or decreased removal of L-lactic acid. In this article, we provide an overview of the biochemical and metabolic aspects of glucose oxidation, the production and removal of L-lactic acid, and a discussion of the pathophysiology of the various causes of L-LA.

Liposome-based codelivery of celecoxib and doxorubicin hydrochloride as a synergistic dual-drug delivery system for enhancing the anticancer effect.

Combination therapy with conventional chemotherapeutic drugs strongly demonstrates a good approach to reduce cytotoxicity, resistance, and the dose of the potent anticancer drugs. The purpose of this research was to design and characterize liposome incorporating celecoxib (CEL) and doxorubicin hydrochloride (DOX) and investigate the anti-tumor efficacy of this combination on different tumor cells. A simple comparison study had been performed for liposomes formulation using thin-film hydration method and pH-gradient method. HSPC-incorporated liposomes were chosen for encapsulation of both CEL and DOX. The formulations showed small particle size and polydispersity index with high encapsulation efficiency. DOX/CEL liposomes displayed the strongest cytotoxicity against B16 and MGC80-3 cells in comparison to the corresponding drug solutions. By incorporation of both agents, a significant reduction in IC50 from 0.927 to 0.198 µg/ml and from 0.81 to 0.535 µg/ml against B16 cells and MGC80-3 cells, respectively, was observed. CEL also significantly improved the intracellular retention and accumulation of DOX in vitro. Our data suggest that the developed liposomal formulation proved to be the most effective formulative strategy as a dual drug delivery system for incorporation of both doxorubicin HCL and CEL and could be considered a useful tool for enhancing the therapeutic efficacy of the anticancer drug.

Renal potassium physiology: integration of the renal response to dietary potassium depletion.

We summarize the current understanding of the physiology of the renal handling of potassium (K+), and present an integrative view of the renal response to K+ depletion caused by dietary K+ restriction. This renal response involves contributions from different nephron segments, and aims to diminish the rate of excretion of K+ as a result of: decreasing the rate of electrogenic (and increasing the rate of electroneutral) reabsorption of sodium in the aldosterone-sensitive distal nephron (ASDN), decreasing the abundance of renal outer medullary K+ channels in the luminal membrane of principal cells in the ASDN, decreasing the flow rate in the ASDN, and increasing the reabsorption of K+ in the cortical and medullary collecting ducts. The implications of this physiology for the association between K+ depletion and hypertension, and K+ depletion and formation of calcium kidney stones are discussed.

Differential expression of CYP2j2 gene and protein in Camelus dromedarius.

CYP2J2 is a member of the cytochrome P450 superfamily. It had been described in different mammalian species; however, no studies have described this gene in Camelus dromedarius. CYP2J2 is an epoxygenase enzyme which oxidizes various fatty acids, mainly arachidonic acid, via NADPH-dependent epoxidation to generate epoxyeicosatrienoic acids (EETs). It is a multi-functional enzyme that plays crucial roles in inflammation, cancer, drug metabolism, and embryo development. It controls the water re-absorption in the kidney and maintains the blood pressure and glucose homeostasis. This study is considered the first report investigating the differential expression profiles of the CYP2J2 mRNA and protein in the liver, heart, and kidney of Camelus dromedarius. A total of 30 samples were used to determine the expression of both CYP2J2 mRNA and protein using qRT-PCR and western blotting methods, respectively. The mRNA level of CYP2J2 was significantly elevated in the liver compared to that in the heart and kidney. The tissue distribution of the CYP2J2 protein was coherent to its transcript level in the kidney, but not in the liver and heart samples. The difference between the CYP2J2 mRNA and protein distributions in the three studied organs may be attributed to the mechanism by which the CYP2J2 might be involved in the adaptability of the camel to the arid environment.

Implication of CDKAL1 single-nucleotide polymorphism rs 9465871 in obese and non-obese Egyptian children.

INTRODUCTION: CDKAL1 single-nucleotide polymorphism rs 9465871variant is a risk locus for Type 2 Diabetes (T2DM).The study evaluated the associations of CDKAL1- rs9465871 with glycosylated hemoglobin A1C Level (HbA1c), fasting insulin level, insulin resistance and metabolic syndrome among obese and non- obese Egyptian children. MATERIALS AND METHODS: The study included 43 obese children and 40 normal weight children. Anthropometric body measurements, bio-specimen and biochemistry assays were done. Genotyping of rs9465871 (CDKAL1) was conducted. RESULTS: The percentages of the CC, CT, and TT genotypes of rs9465871in the lean children were 15%, 42.5%, and 42.5%, respectively. Regarding obese children, the frequencies were 18.6%, 58.1% and 23.3% respectively with no significant statistical difference. Comparison between the CDKAL1 rs 9465871 polymorphism showed that the highest value of fasting insulin was recorded in CC genotype (22.80± 15.18 [uIU/mL] P<.014). Levels of HOMA-IR, FBS and HBA1C were highest in CC group with no statistical significant differences. However, fasting insulin level was higher in the CC group than in the TT+ CT group (P<.01). A higher level of HbA1c was found among CC group at CDKAL1-rs9465871 (5.9%) than TT+CT genotype group (5.6%), with no statistical significant difference. There was increase in the risk of type 2 diabetes the percentages were 78.6% and 46.4% respectively when comparing CC with TT+CT genotype groups ( P<.039). CC group was not associated with significant increase in metabolic syndrome. CONCLUSION: There is a significant risk association between CDKAL1-rs9465871polymorphism and development of T2DM in a subset of the Egyptian children.

Temporal stability in patterns of genetic diversity and structure of a marine foundation species (Zostera marina).

Genetic diversity and population structure reflect complex interactions among a diverse set of processes that may vary temporally, limiting their potential to predict ecological and evolutionary outcomes. Yet, the stability of these patterns is rarely tested. We resampled eelgrass (Zostera marina) meadows from published studies to determine variability in genetic diversity and structure within and between meadows over 5-12 years. The meadows sampled (San Francisco, Tomales and Bodega Bays in California and the Virginia coastal bays) represent a range of life histories (annual vs perennial), age (well-established vs restored) and environments (rural vs urbanized). In all of these systems, neither diversity nor differentiation (FST) changed over time. Differences among tidal heights within Bodega Bay were also remarkably consistent, with the high intertidal being more diverse than the subtidal, and tidal height differentiation being modest but significant at both time points. Historical studies used only a few microsatellite loci; therefore, our temporal comparisons were based on 4-5 loci. However, analysis of the current data using a set of 12 loci show that 4-5 loci are sufficient to describe diversity and differentiation patterns in this system. This temporal consistency was not because of the resampling of large clones, underscoring the feasibility and relevance of understanding drivers of the differences. Because seagrasses are declining at rapid rates, restoration and conservation are increasingly a coastal management priority. Our results argue that surveys of eelgrass genetic structure and diversity at decadal scales can provide accurate depictions of populations, increasing the utility of published genetic data for restoration and designing networks of reserves.

Approach to the Treatment of Diabetic Ketoacidosis.

Diabetic ketoacidosis (DKA), a common cause of severe metabolic acidosis, remains a life-threatening condition due to complications of both the disease and its treatment. This Acid-Base and Electrolyte Teaching Case discusses DKA management, emphasizing complications of treatment. Because cerebral edema is the most common cause of mortality and morbidity, especially in children with DKA, we emphasize its pathophysiology and implications for therapy. The risk for cerebral edema may be minimized by avoiding a bolus of insulin, excessive saline resuscitation, and a decrease in effective plasma osmolality early in treatment. A goal of fluid therapy is to lower muscle venous Pco2 to ensure effective removal of hydrogen ions by bicarbonate buffer in muscle and diminish the binding of hydrogen ions to intracellular proteins in vital organs (such as the brain). In patients with DKA and a relatively low plasma potassium level, insulin administration may cause hypokalemia and cardiac arrhythmias. It is suggested in these cases to temporarily delay insulin administration and first administer potassium chloride intravenously to bring the plasma potassium level close to 4mmol/L. Sodium bicarbonate administration in adult patients should be individualized. We suggest it be considered in a subset of patients with moderately severe acidemia (pH<7.20 and plasma bicarbonate level < 12mmol/L) who are at risk for worsening acidemia, particularly if hemodynamically unstable. Sodium bicarbonate should not be administered to children with DKA, except if acidemia is very severe and hemodynamic instability is refractory to saline administration.

Climate change increases the production of female hatchlings at a northern sea turtle rookery.

The most recent climate change projections show a global increase in temperatures, along with major adjustments to precipitation, throughout the 21st century. Species exhibiting temperature-dependent sex determination are highly susceptible to such changes since the incubation environment influences critical offspring characteristics such as survival and sex ratio. Here we show that the mean incubation duration of loggerhead sea turtle (Caretta caretta) nests from a high-density nesting beach on Bald Head Island, North Carolina, USA has decreased significantly over the past 25 yr. This decrease in incubation duration is significantly positively correlated with mean air temperature and negatively correlated with mean precipitation during the nesting season. Additionally, although no change in hatching success was detected during this same period, a potentially detrimental consequence of shorter incubation durations is that they lead to the production of primarily female offspring. Given that global temperatures are predicted to increase by as much as 4°C over the next century, the mass feminization of sea turtle hatchlings is a high-priority concern. While presently limited in number, studies using long-term data sets to examine the temporal correlation between offspring characteristics and climatic trends are essential for understanding the scope and direction of climate change effects on species persistence.

Serum value of procalcitonin as a marker of intestinal damages: type, extension, and prognosis.

BACKGROUND: Ischemic and necrotic damages are complications of digestive diseases and require emergency management. Nevertheless, the decision to surgically manage could be delayed because of no sufficiently preoperative accurate marker of ischemia diagnosis, extension, and prognosis. METHODS: The aim of this study was to assess the predictive value of serum procalcitonin (PCT) levels for diagnosing intestinal necrotic damages, their extension, and their prognosis in patients with ischemic disease including ischemic colitis and mesenteric infarction by a gray zone approach. Between January 2007 to June 2014, 128 patients with ischemic colitis and mesenteric infarction (codes K55.0 and K51.9) were operated, for whom data on PCT were available. We perform a retrospective, multicenter review of their medical records. Patients were divided into subgroups: ischemia (ID group) versus necrosis (ND group); the extension [focal (FD) vs. extended (ED)] and the vital status [deceased (D) vs. alive (A)]. RESULTS: PCT levels were higher in the ND (n = 94; p = 0.009); ED (n = 100; p = 0.02); and D (n = 70; p = 0.0003) groups. With a gray zone approach, the predictive thresholds were (i) for necrosis 2.473 ng/mL, (ii) for extension 3.884 ng/mL, and (iii) for mortality 7.87 ng/mL. CONCLUSION: In our population, PCT could be used as a marker of necrosis; especially in case of extended damages and reflects the patient's prognosis.

Alterations in bone mineral density and bone turnover markers in newly diagnosed adults with lymphoma receiving chemotherapy: a 1-year prospective pilot study.

BACKGROUND: Bone mineral density (BMD) loss is poorly defined in lymphoma patients. The aim of this study was to measure the extent of BMD loss in newly diagnosed lymphoma patients receiving chemotherapy. PATIENTS AND METHODS: This was a prospective, single-center study conducted in patients aged≥18 years with previously confirmed lymphoma treated by chemotherapy. Patients with low baseline BMD defined as Z/T-score less than or equal to -2.5 and/or history of osteoporotic fractures were excluded. BMD was measured at baseline before initiating chemotherapy and 1 year later. Predictive factors of BMD loss were investigated. RESULTS: Forty-one lymphoma patients (31 males and 10 females) receiving chemotherapy were enrolled. The median age at diagnosis was 59 (range: 19-86) years. Histological subtypes were predominantly diffuse large B-cell lymphoma (58%), mostly stage III-IV (54%). All patients received chemotherapy and 22% of patients received second-line treatment due to relapse or progressive disease. Thirty-two patients were evaluable at 1 year. The mean BMD changes were: -2.7%±3.9% for lumbar spine (P<0.001), -2.2%±7.6% for femoral neck (P<0.01) and -2.6%±4.5% for total hip (P<0.0001). In multivariate analysis, predictive factors of BMD loss at baseline were (i) at lumbar spine: female gender (P=0.01), higher lactate dehydrogenase level (P=0.04) and lower creatinine clearance (P=0.01); (ii) at total hip: lower albumin (P=0.01), higher corrected serum calcium (P<0.01), lower alkaline phosphatase (AP) (P<0.01) and autologous stem cell transplant (P=0.03); and (iii) at femoral neck: higher corrected serum calcium (P=0.02) and lower bone AP (P=0.01). CONCLUSION: Adult patients with known lymphoma receiving chemotherapy experienced significant BMD loss at 1 year.

Integration of the response to a dietary potassium load: a paleolithic perspective.

Our purpose is to integrate new insights in potassium (K(+)) physiology to understand K(+) homeostasis and illustrate some of their clinical implications. Since control mechanisms that are essential for survival were likely developed in Paleolithic times, we think the physiology of K(+) homeostasis can be better revealed when viewed from what was required to avoid threats and achieve balance in Paleolithic times. Three issues will be highlighted. First, we shall consider the integrative physiology of the gastrointestinal tract and the role of lactic acid released from enterocytes following absorption of sugars (fruit and berries) to cause a shift of this K(+) load into the liver. Second, we shall discuss the integrative physiology of WNK kinases and modulation of delivery of bicarbonate to the distal nephron to switch the aldosterone response from sodium chloride retention to K(+) secretion when faced with a K(+) load. Third, we shall emphasize the role of intra-renal recycling of urea in achieving K(+) homeostasis when the diet contains protein and K(+).

Synergetic effect of essential oils and calcium phosphate nanoparticles for enhancement the corrosion resistance of titanium dental implant.

Calcium phosphate (CaPO4) coating is one of various methods that is used to modify the topography and the chemistry of Ti dental implant surface to solve sever oral problems that result from diseases, accidents, or even caries due to its biocompatibility. In this work, anodized (Ti-bare) was coated by CaPO4 prepared from amorphous calcium phosphate nanoparticles (ACP-NPs) and confirmed the structure by X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FT-IR) techniques. Ti-bare was coated by prepared CaPO4 through the casting process, and the morphology of Ti/CaPO4 was characterized by scanning electron microscope (SEM) where the nano-flakes shape of CaPO4 and measured to be 60 ~ 80 nm was confirmed. The stability of Ti-bare and coated Ti/CaPO4 was studied in a simulated saliva solution using electrochemical impedance spectroscopy (EIS) and linear polarization techniques to deduce their corrosion resistance. Furthermore, three essential oils (EO), Cumin, Thyme, and Coriander, were used to stimulate their synergistic effect with the CaPO4 coat to enhance the corrosion resistance of Ti implant in an oral environment. The fitting EIS parameters based on Rs [RctC]W circuit proved that the charge transfer resistance (Rct) of Ti/CaPO4 increased by 264.4, 88.2, and 437.5% for Cumin, Thyme, and Coriander, respectively, at 2% concentration.

Filtering Organized 3D Point Clouds for Bin Picking Applications.

In robotic bin-picking applications, autonomous robot action is guided by a perception system integrated with the robot. Unfortunately, many perception systems output data contaminated by spurious points that have no correspondence to the real physical objects. Such spurious points in 3D data are the outliers that may spoil obstacle avoidance planning executed by the robot controller and impede the segmentation of individual parts in the bin. Thus, they need to be removed. Many outlier removal procedures have been proposed that work very well on unorganized 3D point clouds acquired for different, mostly outdoor, scenarios, but these usually do not transfer well to the manufacturing domain. This paper presents a new filtering technique specifically designed to deal with the organized 3D point cloud acquired from a cluttered scene, which is typical for a bin-picking task. The new procedure was tested on six different datasets (bins filled with different parts) and its performance was compared with the generic statistical outlier removal procedure. The new method outperforms the general procedure in terms of filtering efficacy, especially on datasets heavily contaminated by numerous outliers.