Physiologically Based Trimester-Specific Serum Ferritin Thresholds for Iron Deficiency in US Pregnant Women.

Serum ferritin (SF) concentration is the most widely used indicator for iron deficiency (ID). During pregnancy, the World Health Organization recently recommended SF thresholds for ID of <15 µg/L for the 1st trimester of pregnancy, based on expert opinion, and made no recommendations for the 2nd and 3rd trimesters. We examined the relationship of SF with two independent indicators of the onset of iron-deficient erythropoiesis, hemoglobin (Hb) and soluble transferrin receptor 1 (sTfR1), in cross-sectional data from NHANES for 1999-2010 and 2015-2018. We included 1288 pregnant women 15-49 years and excluded women with inflammation or potential liver disease. We used restricted cubic spline (RCS) regression analysis to determine SF thresholds for iron-deficient erythropoiesis. SF decreased during pregnancy; geometric mean SF was higher during the 1st and lower during the 2nd and 3rd trimesters. Using RCS analysis, the SF thresholds identified during pregnancy were <25.8 (18.1, 28.5) µg/L during 1st trimester, <18.3 (16.3, 22.9) µg/L during 2nd trimester, and <19.0 (14.4, 26.1) µg/L during 3rd trimester. These SF threshold levels track concentrations of hepcidin, the iron regulatory hormone controlling the mobilization of iron stores. A SF concentration of <15 µg/L as the criterion for ID may underestimate the true prevalence of ID throughout pregnancy. In our study, an additional one of every ten pregnant women would be recognized as iron deficient by using the physiologically based thresholds at SF of about 25 µg/L during the 1st and of about 20 µg/L during the 2nd and 3rd trimesters.

Preoperative Levosimendan in Patients With Severe Left Ventricular Dysfunction Undergoing Isolated Coronary Artery Bypass Grafting: A Meta-Analysis of Randomized Controlled Trials.

OBJECTIVE: To verify the impact of preoperative levosimendan on patients with severe left ventricular dysfunction (ejection fraction <35%) undergoing isolated coronary artery bypass grafting. DESIGN: A meta-analysis. SETTING: Hospitals. PARTICIPANTS: The authors included 1,225 patients from 6 randomized controlled trials. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The authors performed a meta-analysis of trials that compared preoperative levosimendan with placebo or no therapy, reporting efficacy and safety endpoints. Statistical analyses used mean differences and risk ratios (RR), with a random effects model. Six studies were included, comprising 1,225 patients, of whom 615 (50.2%) received preoperative levosimendan, and 610 (49.8%) received placebo/no therapy. Preoperative levosimendan showed a lower risk of all-cause mortality (RR 0.31; 95% CI 0.16-0.60; p < 0.01; I2 = 0%), postoperative acute kidney injury (RR 0.44; 95% CI 0.25-0.77; p < 0.01; I2 = 0%), low-cardiac-output syndrome (RR 0.45; 95% CI 0.30-0.66; p < 0.001; I2 = 0%), and postoperative atrial fibrillation (RR 0.49; 95% CI 0.25-0.98; p = 0.04; I2 = 85%) compared to control. Moreover, levosimendan significantly reduced the need for postoperative inotropes and increased the cardiac index at 24 hours postoperatively. There were no differences between groups for perioperative myocardial infarction, hypotension, or any adverse events. CONCLUSION: Preoperative levosimendan in patients with severe left ventricular dysfunction undergoing isolated coronary artery bypass grafting was associated with reduced all-cause mortality, low-cardiac-output syndrome, acute kidney injury, postoperative atrial fibrillation, and the need for circulatory support without compromising safety.

Nearly complete structure of bacteriophage DT57C reveals architecture of head-to-tail interface and lateral tail fibers.

The T5 family of viruses are tailed bacteriophages characterized by a long non-contractile tail. The bacteriophage DT57C is closely related to the paradigmal T5 phage, though it recognizes a different receptor (BtuB) and features highly divergent lateral tail fibers (LTF). Considerable portions of T5-like phages remain structurally uncharacterized. Here, we present the structure of DT57C determined by cryo-EM, and an atomic model of the virus, which was further explored using all-atom molecular dynamics simulations. The structure revealed a unique way of LTF attachment assisted by a dodecameric collar protein LtfC, and an unusual composition of the phage neck constructed of three protein rings. The tape measure protein (TMP) is organized within the tail tube in a three-stranded parallel α-helical coiled coil which makes direct contact with the genomic DNA. The presence of the C-terminal fragment of the TMP that remains within the tail tip suggests that the tail tip complex returns to its original state after DNA ejection. Our results provide a complete atomic structure of a T5-like phage, provide insights into the process of DNA ejection as well as a structural basis for the design of engineered phages and future mechanistic studies.

Outcome of patients supported with the HeartMate 3 after extracorporeal life support: On behalf of the Durable Mechanical Circulatory Support After Extracorporeal Life Support Study Group.

OBJECTIVES: The Durable Mechanical Circulatory Support System After Extracorporeal Life Support registry is a multicenter registry of patients who were bridged from extracorporeal life support to a durable mechanical circulatory support system. Although numerous studies have highlighted the favorable outcomes after implantation of the HeartMate 3 (Abbott), the objective of our study is to examine the outcomes of patients who received HeartMate 3 support after extracorporeal life support. METHODS: Data of patients undergoing HeartMate 3 implantation from January 2016 to April 2022 at 14 centers were collected and evaluated. Inclusion criteria were patients with extracorporeal life support before HeartMate 3 implantation. The outcome was reported and compared with patients receiving other types of pumps. RESULTS: A total of 337 patients were bridged to durable mechanical circulatory support system after extracorporeal life support in the study period. Of those patients, 140 were supported with the HeartMate 3. The other types of pumps included 170 HeartWare HVADs (Medtronic) (86%), 14 HeartMate II devices (7%), and 13 (7%) other pumps (7%). Major postoperative complications included right heart failure requiring temporary right ventricular assist device in 60 patients (47%). Significantly lower postoperative stroke (16% vs 28%, P = .01) and pump thrombosis (3% vs 8%, P = .02) rates were observed in the patients receiving the HeartMate 3. The 30-day, 1-year, and 3-year survivals in patients receiving the HeartMate 3 were 87%, 73%, and 65%, respectively. CONCLUSIONS: In this critically ill patient population, the survivals of patients who were transitioned to the HeartMate 3 are deemed acceptable and superior to those observed when extracorporeal life support was bridged to other types of durable mechanical circulatory support systems.

Trends in Micronutrient Interventions, Anemia, and Iron Deficiency among Women and Children in Guatemala, 2009-2019.

Background: Food fortification and micronutrient supplementation are public health strategies to improve micronutrient status in Guatemala; their population effectiveness has not been evaluated in recent years. Objective: We evaluated trends in food fortification, micronutrient supplementation, anemia, and iron deficiency among nonpregnant women aged 15-49 y [women of reproductive age (WRA)] and children 6-59 aged mo [preschool age children (PSC)]. Method: Nationally representative serial cross-sectional surveys were used to assess changes in hemoglobin, anemia, ferritin, iron deficiency, iron deficiency anemia, and self-reported consumption of fortifiable foods and micronutrient supplements during 2008/2009, 2013, 2015, 2016, 2017/2018, and 2018/2019. Predictors of hemoglobin and ferritin were assessed using generalized linear mixed models adjusted for survey year as random effects, and the consumption of fortifiable foods, supplements, and other potential confounders were fixed effects. Results: Multiple micronutrient powder consumption among PSC during the previous 3 mo was 53.3% (95% CI: 49.4, 57.2) in 2013 and 33.6% (28.8, 38.4) in 2018/2019. Anemia among PSC was 11.3% (8.0, 14.5) in 2008/2009 and 6.1% (3.6, 8.6) in 2018/2019. Anemia among WRA was 10.7% (7.2, 14.2) in 2008/2009 and 3.9% (2.7, 5.2) in 2018/2019. Iron deficiency among PSC was 15.5% (12.1, 19.0) in 2008/2009 and 10.9% (7.4, 14.5) in 2016 (lowest), but 17.1 (13.3, 21.0) in 2017/2018 (highest). Iron deficiency among WRA was 14.9% (11.6, 18.2) in 2008/2009, 13.8% (11.8, 15.8) in 2013 (lowest), and 18.9% (16.3, 21.6) in 2017/2018 (highest). Wheat flour/bread consumption was positively associated with hemoglobin among PSC, and sugar consumption was positively associated with hemoglobin among WRA. The reported consumption of fortifiable foods was not associated with ferritin among PSC or WRA. Conclusions: Guatemala has implemented multiple food fortification strategies, and anemia has declined. Increases in iron deficiency in 2017-2019 warrant further attention. Secular trends toward poverty alleviation, education, and development might be responsible for changes not explained by the micronutrient interventions evaluated.

Insuficiencia respiratoria en una paciente con síndrome de Sézary / Respiratory failure in a patient with Sézary syndrome

Paciente de 44 años de sexo femenino, sin ninguna enfermedad de base preexistente, con una historia de aproximadamente diez meses de presentar lesiones eritemato-descamativas pruriginosas inicialmente localizadas en extremidades inferiores y que luego se generalizaron en todo el cuerpo, asociándose a la pérdida de peso de aproximadamente 15 kg. El manejo inicial consistió en corticoides tópicos y antihistamínicos orales con poca respuesta clínica. Se inició el estudio por dermatología y se confirmó el diagnóstico inicial de neoplasia cutánea maligna de células T. Luego se realizó el frotis de médula ósea, en el que se identificaron células «cerebriformes¼ que confirmaron el diagnóstico de síndrome de Sézary. La paciente recibió esquema de quimioterapia ciclofosfamida, doxorrubicina, vincristina, etopósido y prednisona. La respuesta inicial fue favorable, con alta hospitalaria y seguimiento en la consulta externa. Transcurridos tres meses de tratamiento, la paciente consultó por episodio febril, tos productiva más distrés respiratorio asociado a estertores basales bilaterales, presentó insuficiencia respiratoria y durante la inducción a la ventilación mecánica sufrió un paro cardiorrespiratorio y falleció

44-year-old female patient, with no preexisting underlying disease, with a history of approximately ten months of presenting pruritic erythematous-desquamative lesions initially localized in the lower extremities and later generalized throughout the body, associated with weight loss of 15 kg. Treatment. Initial management consisted of topical corticosteroids and oral antihistamines with little clinical response. A dermatology wok-up was initiated, and the initial diagnosis of malignant T-cell neoplasm was confirmed. A bone marrow smear was performed, in which "cerebriform" cells were identified, confirming the diagnosis of Sézary syndrome. The patient received cyclophosphamide, doxorubicin, vincristine, etoposide, and prednisone chemotherapy. Outcome. The initial response was favorable, with hospital discharge and outpatient follow-up. After three months of treatment, the patient consulted for a febrile episode, productive cough plus respiratory distress associated with bilateral basal rales, presented respiratory failure, and during induction of mechanical ventilation suffered cardiorespiratory arrest and died.

Moderation effects of loneliness between fatalism and wellbeing during the COVID-19 pandemic.

The COVID-19 pandemic has put more than just our physical health at risk. Due to containment measures, people have become increasingly isolated and have drastically reduced their daily social interactions. Many studies have already shown the negative effects of these measures, including fatalism. However, research linking fatalism during COVID-19 to well-being indicators is still limited. The goal of this study is to examine the relationship between COVID-19-related fatalism and well-being indicators, as well as the role of loneliness in moderating this relationship. Data was collected from 1,036 adults in Peru through an online survey that included the Quality-of-Life Index, the Fatalism Facing COVID-19 Scale, the Loneliness Scale, and the Mood Assessment Scale. Three models were tested using linear regression and ordinary least squares with bias-corrected bootstrapping. The results indicate that fatalism has a negative impact on quality of life and a positive effect on negative affect, and loneliness moderates both relationships, supporting the conclusion that fatalism exacerbates the effect of well-being indicators and negative affect.

Fruit, Vegetable, and Sugar-Sweetened Beverage Intake Among Young Children, by State - United States, 2021.

Good nutrition in early childhood supports optimal growth, development, and health (1). Federal guidelines support a dietary pattern with daily fruit and vegetable consumption and limited added sugars, including limited consumption of sugar-sweetened beverages (1). Government-published dietary intake estimates for young children are outdated at the national level and unavailable at the state level. CDC analyzed data from the 2021 National Survey of Children's Health (NSCH)* to describe how frequently, according to parent report, children aged 1-5 years (18,386) consumed fruits, vegetables, and sugar-sweetened beverages, nationally and by state. During the preceding week, approximately one in three (32.1%) children did not eat a daily fruit, nearly one half (49.1%) did not eat a daily vegetable, and more than one half (57.1%) drank a sugar-sweetened beverage at least once. Estimates of consumption varied by state. In 20 states, more than one half of children did not eat a vegetable daily during the preceding week. In Vermont, 30.4% of children did not eat a daily vegetable during the preceding week, compared with 64.3% in Louisiana. In 40 states and the District of Columbia, more than one half of children drank a sugar-sweetened beverage at least once during the preceding week. The percentage of children drinking sugar-sweetened beverages at least once during the preceding week ranged from 38.6% in Maine to 79.3% in Mississippi. Many young children are not consuming fruits and vegetables daily and are regularly consuming sugar-sweetened beverages. Federal nutrition programs and state policies and programs can support improvements in diet quality by increasing access to and availability of fruits and vegetables and healthy beverages in places where young children live, learn, and play.

Comparison of Current World Health Organization Guidelines with Physiologically Based Serum Ferritin Thresholds for Iron Deficiency in Healthy Young Children and Nonpregnant Women Using Data from the Third National Health and Nutrition Examination Survey.

BACKGROUND: Current WHO serum ferritin (SF) thresholds for iron deficiency (ID) in children (<12 µg/L) and women (<15 µg/L) are derived from expert opinion based on radiometric assays in use decades ago. Using a contemporary immunoturbidimetry assay, higher thresholds (children, <20 µg/L; women, <25 µg/L) were identified from physiologically based analyses. OBJECTIVE: We examined relationships of SF measured using an immunoradiometric assay from the era of expert opinion with 2 independently measured indicators of ID, hemoglobin (Hb) and erythrocyte zinc protoporphyrin (eZnPP), using data from the Third National Health and Nutrition Examination Survey (NHANES III, 1988-1994). The SF at which circulating Hb begins to decrease and eZnPP begins to increase provides a physiological basis for identifying the onset of iron-deficient erythropoiesis. METHODS: We analyzed NHANES III cross-sectional data from 2616 apparently healthy children, aged 12-59 mo, and 4639 apparently healthy nonpregnant women, aged 15-49 y. We used restricted cubic spline regression models to determine SF thresholds for ID. RESULTS: SF thresholds identified by Hb and eZnPP did not differ significantly in children, 21.2 µg/L (95% confidence interval: 18.5, 26.5) and 18.7 µg/L (17.9, 19.7), and, in women, were similar although significantly different, 24.8 µg/L (23.4, 26.9) and 22.5 µg/L (21.7, 23.3). CONCLUSIONS: These NHANES results suggest that physiologically based SF thresholds are higher than the thresholds from expert opinion established during the same era. SF thresholds found using physiological indicators detect the onset of iron-deficient erythropoiesis, whereas the WHO thresholds identify a later, more severe stage of ID.

Stroke Complications in Patients Requiring Durable Mechanical Circulatory Support Systems After Extracorporeal Life Support.

Stroke is one of the leading complications following durable mechanical circulatory support (MCS) implantation. The aim of this multicenter study was to investigate stroke complications in patients requiring durable MCS following extracorporeal life support (ECLS). Data of 11 high volume MCS centers were collected and evaluated to identify patients who underwent durable MCS implantation after ECLS support between January 2010 and August 2018. The primary outcome was stroke following durable MCS implantation. Univariate and multivariate logistic regression analyses were performed to determine predictors of stroke. Overall, 531 patients met the inclusion criteria. Only patients who were supported with continuous flow pumps were included in this study accounting for 495 patients (median age 54 years old [interquartile range 47-60]). A total of 136 patients (27%) developed postoperative stroke on device during the follow-up (48% ischemic and 52% hemorrhagic) after a median durable MCS support of 320 [32-1,000] days, accounting for 0.17 events per patient-year. Of 133 patients with known date of stroke, a total of 47 (10%) developed stroke during the first 30 days (64% ischemic and 36% hemorrhagic), and 86 patients developed stroke after 30 days (38% ischemic and 62% hemorrhagic) of durable MCS support (late stroke). Survival rate was significantly lower in patients with hemorrhagic stroke ( p = 0.00091). Stroke appears to be a common complication in patients transitioned to durable MCS support after ECLS. Hemorrhagic stroke is a more common type of late stroke and is associated with inferior outcomes.

Ameloblastoma metastásico / Metastatic ameloblastoma

77REPERT MED CIR. 2023;32(1):77-80Mario Alexander Melo MD*María Camila PiñerosbAna María TorresbFabián Parra F. MDcRafael Baracaldo A. MDda Patología. Grupo de Patología Oncológica, Instituto Nacional de Cancerología, Universidad El Bosque. Bogotá DC, Colombia. b Odontólogía, Patología Oral y Medios Diagnósticos, Universidad El Bosque, Bogotá DC, Colombia. c Radiología e Imágenes Diagnósticas, Fundación Universitaria Sanitas, Bogotá DC, Colombia. d Patología, Fundación Universitaria de Ciencias de la Salud. Bogotá DC, Colombia.Introducción: el ameloblastoma es un tumor epitelial benigno de origen odontogénico, de crecimiento progresivo, caracterizado por expansión ósea y tendencia a la recurrencia local si no se trata en forma adecuada. De acuerdo con las características clínicas y radiográficas se clasifica en ameloblastoma uniquístico, periférico/extraóseo y el metastásico. Presentación del caso: el presente manuscrito se quiere reseñar el caso clínico de un ameloblastoma metastásico, el cual es capaz de producir siembras a pesar de su apariencia histológica benigna. Discusión y conclusiones: las variadas formas clínicas y radiográficas hacen que el ameloblastoma metastásico requiera, desde su diagnóstico inicial, un estudio detallado ya que es importante entender el concepto de esta patología como lesión clínica que realiza metástasis a distancia, pero su comportamiento histológico es benigno

Introduction: ameloblastoma is a benign epithelial odontogenic tumor that progresses slowly and is characterized by bone expansion and tendency for local recurrence if not treated properly. According to the clinical and radiographic characteristics, it is classified as unicystic, peripheral/extraosseous and metastatic ameloblastoma. Case presentation: the present manuscript aims to review the clinical case of a metastatic ameloblastoma, which can metastasize in spite of a benign histological appearance. Discussion and conclusions: the various clinical and radiographic forms of metastatic ameloblastoma require, from its initial diagnosis, a detailed study, since it is important to understand the concept of this clinico-pathological entity as a lesion with distant metastases but benign histological features

The Relationship Between Ferritin and BMI is Mediated by Inflammation Among Women in Higher-Income Countries, But Not in Most Lower-Income Countries Nor Among Young Children: A Multi-Country Analysis.

Background: In the presence of inflammation, the serum or plasma ferritin concentration ("ferritin" hereafter) transiently increases, confounding its interpretation as an iron status marker. The extent to which adiposity-related inflammation may influence ferritin interpretation is uncertain. Objectives: We describe relationships between weight status, inflammation, and ferritin among nonpregnant women of reproductive age (WRA; 15-49 years) and preschool-age children (PSC; 6-59 months) with normal weight to overweight or obesity (OWOB) in differing geographic settings. Methods: Cross-sectional data were separately analyzed from 18 surveys (WRA) and 25 surveys (PSC) from the Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project, excluding observations with underweight, wasting, pregnancy, or malaria. Relationships were assessed between BMI (in WRA) or BMI-for-age z-score (BAZ; in PSC), inflammatory biomarkers of C-reactive protein (CRP) and/or α-1-acid glycoprotein (AGP), ferritin by linear regression, and potential mediation by CRP and/or AGP in relationships between BMI or BAZ and ferritin with structural equation modeling. Regression and mediation models accounted for complex survey designs. Results were grouped by World Bank income classifications. Results: In 5 of 6 surveys among WRA from upper-middle and high-income countries, ferritin was significantly positively associated with BMI, and this relationship was partially (or fully, in the United States) mediated by CRP and/or AGP. Mediation was present in 4 of 12 surveys for WRA in low- and lower-middle income countries. Among PSC, ferritin was positively associated with CRP and/or AGP in all surveys, but there were no significant CRP- or AGP-mediated relationships between ferritin and BAZ, except a negative relationship in the Philippines. Conclusions: Where having OWOB is common among WRA, measurements of inflammatory biomarkers and their uses in interpreting ferritin may improve iron status assessments. While these relationships were inconsistent among PSC, inflammation was common and should be measured to interpret iron status. Included Kenyan trial data are registered at clinicaltrials.gov as NCT01088958.

Iron Deficiency in the United States: Limitations in Guidelines, Data, and Monitoring of Disparities.

Iron deficiency and the more severe sequela, iron deficiency anemia, are public health problems associated with morbidity and mortality, particularly among pregnant women and younger children. The 1998 Centers for Disease Control and Prevention recommendations for prevention and control of iron deficiency in the United States is old and does not reflect recent evidence but is a foundational reference for many federal, clinical, and program guidelines. Surveillance data for iron deficiency are sparse at all levels, with critical gaps for pregnant women and younger children. Anemia, iron deficiency, and iron deficiency anemia are often conflated but should not be. Clinical guidelines for anemia, iron deficiency, and iron deficiency anemia give inconsistent recommendations, causing nonsystematic assessment of iron deficiency. Screening for iron deficiency typically relies on identifying anemia, despite anemia's low sensitivity for iron deficiency. In the National Health and Nutrition Examination Survey, more than 70% of iron deficiency is missed among pregnant women and children by relying on hemoglobin for iron deficiency screening. To improve assessment and diagnosis and strengthen surveillance, better and more complete data and updated foundational guidance on iron deficiency and anemia are needed that consider new evidence for measuring and interpreting laboratory results. (Am J Public Health. 2022;112(S8):S826-S835. https://doi.org/10.2105/AJPH.2022.306998).

Improving Nutrition in the First 1000 Days in the United States: A Federal Perspective.

The first 1000 days begins with pregnancy and ends at the child's second birthday. Nutrition throughout the life course, and especially during the first 1000 days, supports maternal health and optimal growth and development for children. We give a high-level summary of the state of nutrition in the first 1000 days in the United States. We provide examples where continued efforts are needed. We then discuss select opportunities to strengthen federal research and surveillance, programs, and communication and dissemination efforts aimed at improving nutrition and positively, and equitably, influencing the health and well-being of mothers and children. (Am J Public Health. 2022;112(S8):S817-S825. https://doi.org/10.2105/AJPH.2022.307028).

Experiences and Lessons Learned in Developing and Implementing a Population-Based Nutrition and Health Surveillance System in Guatemala 2011-2021.

Background: Practice-based experiences documenting development and implementation of nutrition and health surveillance systems are needed. Objectives: To describe processes, methods, and lessons learned from developing and implementing a population-based household nutrition and health surveillance system in Guatemala. Methods: The phases and methods for the design and implementation of the surveillance system are described. Efforts to institutionalize the system in government institutions are described, and illustrative examples describing different data uses, and lessons learned are provided. Results: After initial assessments of data needs and consultations with officials in government institutions and partners in the country, a population-based nutrition surveillance system prototype with complex sampling was designed and tested in 5 Guatemalan Highland departments in 2011. After dissemination of the prototype, government and partners expanded the content, and multitopic nutrition and health surveillance cycles were collected in 2013, 2015, 2016, 2017/18, and 2018/19 providing nationally representative data for households, women of reproductive age (15-49 y), and children aged 0-59 mo. For each cycle, data were to be collected from 100 clusters, 30 households in each, and 1 woman and 1 child per household. Content covered ∼25 health and nutrition topics, including coverage of all large-scale nutrition-specific interventions; the micronutrient content of fortifiable sugar, salt, and bread samples; anthropometry; and biomarkers to assess annually, or at least once, ∼25 indicators of micronutrient status and chronic disease. Data were collected by 3-5 highly trained field teams. The design was flexible and revised each cycle allowing potential changes to questionnaires, population groups, biomarkers, survey design, or other changes. Data were used to change national guidelines for vitamin A and B-12 interventions, among others, and evaluate interventions. Barriers included frequent changes of high-level government officials and heavy dependence on US funding. Conclusions: This system provides high-quality data, fills critical data gaps, and can serve as a useful model for others.

Investigating Instructor Talk among Graduate Teaching Assistants in Undergraduate Biology Laboratory Classrooms.

Instructor Talk-noncontent and nonlogistical language that is focused on shaping the classroom learning environment-is a recently defined variable that may play an important role in how undergraduates experience courses. Previous research characterized Instructor Talk used by faculty teaching in biology lecture classrooms. However, graduate teaching assistants (GTAs) and laboratory classrooms represent critical factors in undergraduate education, and Instructor Talk in this context has yet to be explored. Here, we present findings analyzing Instructor Talk used by GTAs teaching in undergraduate biology laboratory classrooms. We characterized the Instructor Talk used by 22 GTA instructors across 24 undergraduate biology laboratory courses in the context of a single, urban, Hispanic-serving and Asian American and Pacific Islander-serving Institution. We found that Instructor Talk was present in every course studied, GTAs with pedagogical training and prior teaching experience used more Instructor Talk than those without, and GTAs teaching laboratory courses used more Instructor Talk than previous observations of faculty teaching lecture courses. Given the widespread use of Instructor Talk and its varying use across contexts, we predict that Instructor Talk may be a critical variable in teaching, specifically in promoting equity and inclusion, which merits continued study in undergraduate science education.

Physiologically based serum ferritin thresholds for iron deficiency in women of reproductive age who are blood donors.

Our objective is to develop a physiologically based method to determine serum ferritin thresholds for iron deficiency in healthy individuals. The current World Health Organization threshold of <15 µg/L for iron deficiency in women is based on expert opinion. We examined the relationship between serum ferritin and 2 independently measured indicators of iron-deficient erythropoiesis, soluble transferrin receptor (sTfR) and hemoglobin, in baseline data from 286 women, 20 to 49 years, who were first-time or reactivated donors in the Retrovirus Epidemiology Donor Study-II Donor Iron Status Evaluation (REDS-RISE) study. At lower serum ferritin concentrations, median sTfR increased as hemoglobin decreased. Using restricted cubic spline regression analysis to determine thresholds for iron-deficient erythropoiesis, the thresholds identified by sTfR (serum ferritin < 25.4 µg/L) and hemoglobin (serum ferritin < 25.3 µg/L) did not differ significantly. The thresholds found in the REDS-RISE study do not differ from those identified by sTfR (serum ferritin < 25.5 µg/L) and hemoglobin (serum ferritin < 26.6 µg/L) in a previous study of 5442 women, 20 to 49 years, in the US National Health and Nutrition Examination Survey 2003 to 2018 (P = .98 and 0.83, respectively). Although international comparisons are needed, these results with US data provide additional evidence for the potential usefulness of a physiologically based method to identify serum ferritin thresholds for iron deficiency.

Approaches to quantify the contribution of multiple anemia risk factors in children and women from cross-sectional national surveys.

BACKGROUND: Attributable fractions (AF) of anemia are often used to understand the multifactorial etiologies of anemia, despite challenges interpreting them in cross-sectional studies. We aimed to compare different statistical approaches for estimating AF for anemia due to inflammation, malaria, and micronutrient deficiencies including iron, vitamin A, vitamin B12, and folate. METHODS: AF were calculated using nationally representative survey data among preschool children (10 countries, total N = 7,973) and nonpregnant women of reproductive age (11 countries, total N = 15,141) from the Biomarkers Reflecting Inflammation and Nutrition Determinants of Anemia (BRINDA) project. We used the following strategies to calculate AF: 1) Levin's formula with prevalence ratio (PR) in place of relative risk (RR), 2) Levin's formula with odds ratio (OR) in place of RR, and 3) average (sequential) AF considering all possible removal sequences of risk factors. PR was obtained by 1) modified Poisson regression with robust variance estimation, 2) Kleinman-Norton's approach, and 3) estimation from OR using Zhang-Yu's approach. Survey weighted country-specific analysis was performed with and without adjustment for age, sex, socioeconomic status, and other risk factors. RESULTS: About 20-70% of children and 20-50% of women suffered from anemia, depending on the survey. Using OR yielded the highest and potentially biased AF, in some cases double those using PR. Adjusted AF using different PR estimations (Poisson regression, Kleinman-Norton, Zhang-Yu) were nearly identical. Average AF estimates were similar to those using Levin's formula with PR. Estimated anemia AF for children and women were 2-36% and 3-46% for iron deficiency, <24% and <12% for inflammation, and 2-36% and 1-16% for malaria. Unadjusted AF substantially differed from adjusted AF in most countries. CONCLUSION: AF of anemia can be estimated from survey data using Levin's formula or average AF. While different approaches exist to estimate adjusted PR, Poisson regression is likely the easiest to implement. AF are a useful metric to prioritize interventions to reduce anemia prevalence, and the similarity across methods provides researchers flexibility in selecting AF approaches.