bluuebunny/crossref_metadata_2025 huggingface dataset:
Isolation and Classification of Bacteriophages in Untreated and Treated Sewage to Test Effectiveness of Water Treatment Methods
Authors: Meuer Katie , Piefer Andrew , Allen Mary , Balogh‐Brunstad Zsuzsanna
Published: June 2021

The research for this project will focus on studying the differences between the number of bacteriophages and their specificity present in a natural environment sewage sample before and after being processed through the Oneonta, New York wastewater treatment system. Sewage provides an ideal environment for many bacteriophages to grow including those with bacterial hosts Escherichia, Enterobacter, Serratia, and Alcaligenes. Samples of sewage will be collected and enriched with one of the aforementioned hosts, and then filtered to isolate virus. Host and phage combinations will then be used to prepare plaque assays to determine phage titer. The plaques will be harvested and grown again to isolate the specific phage and determine its bacterial host range specificity. Phage classification will be based on DNA isolation and restriction fragment comparison. Data will be submitted to the Mycobacteria Phage Database Project. The same isolation and classification procedure will be followed with post water treatment samples, to measure potential reduction in phage titer and / or changes in host range specificity. This project was funded by the Hartwick College Department of Chemistry.
Toxin‐antitoxin systems and their role(s) in persistence
Authors: Page Rebecca , Peti Wolfgang
Published: June 2021

During the last decade, efforts to understand the molecular mechanism(s) that underlie bacterial persistence have accelerated substantially. In spite of these efforts, the molecular activities that lead to the persister phenotype remain largely unknown. Persister cells are characterized by an upregulation of genes known as toxin‐antitoxin (TA) pairs, with the toxin mqsR being the most highly upregulated gene in E. coli persisters. During normal cell growth, MqsR and its antitoxin, MqsA, form a non‐toxic complex. However, during stress, MqsA is degraded allowing MqsR to induce growth arrest via mRNA cleavage. We previously reported that the mqsRA TA pair is unique because of the unusual features of MqsA. Now, our most recent work reveals that MqsR also has exclusive properties. Using X‐ray crystallography, mutagenesis, in vitro RNA cleavage assays, EMSAs and ITC, we show that, unlike all other TA systems, the MqsR‐MqsA complex cannot bind DNA. Instead, MqsR functions solely as a de‐repressor, further promoting multidrug tolerance through its ability to disrupt MqsA‐mediated repression of persistence‐related genes. Furthermore, using in vitro studies, we discovered that MqsR is a ‘hybrid’ endoribonuclease (RNase), having characteristics of both RelE‐like and microbial like RNases. Recent work has defined the mechanism of mRNA cleavage and the molecular basis of MqsA neutralization of MqsR activity. Finally, we also discovered a novel Type V TA system that is activated by MqsR, the first TA system has been shown to regulate a second. Collectively, these studies demonstrate that MqsR‐MqsA defines a novel TA system and are ideal targets for developing a new class of antibiotics that inhibit the persister state.

This work was supported by an NSF‐CAREER award (MCB0952550) to RP.
Analyzing Bacterial Communities in Pediculus humanus capitis
Authors: Plekan Mollie , St Amand Megan , Klepac‐Ceraj Vanja , Peterson Celeste
Published: June 2021

Understanding the composition of the microbiome of human associated insects can shed light on the sources of potential human pathogens. The human head louse, Pediculus humanus capitis, is an obligate symbiont found in the hair of humans, especially children. It is known to harbor an obligate endosymbiont, Candidatus Reisia. However, a complete survey of head louse microbiome has not been described to date. The purpose of this research is to begin to analyze the louse microbiome and determine if it differs between individual human hosts. DNA was isolated from lice from individuals hosts and the 16S gene amplified for Illumina sequencing of the V3‐V5 variable region followed by analysis with Qiime. Results showed that the expected obligate endosymbiont, Candidatus Reisia, made up over 95% of the community throughout all of the samples. Other taxa that were commonly found in the samples included Prevotella, Streptoccocus and Veillonella. The communities varied among individual lice and among human hosts. This survey is the first reported measurement of the entire microbial community associated with the human head louse.
A New Method for High Throughput Quantification of Bacterial Clades in Sediment Samples
Authors: Von Rosen Tatjana , Probandt David , Knittel Katrin
Published: June 2021

Microbial community changes are followed through next generation sequencing (NGS) based comparative sequence analysis. However, actual in situ abundance for clades is determined via catalyzed reporter deposition fluorescence in situ hybridization (CARD FISH) and has revealed successive distinctive abundance peaks of Flavobacteria and Gammaproteobacteria for planktonic communities in response to phytoplankton blooms. Although seasonal benthic community changes have been descried, the response of in situ abundance of the community and potentially adapted clades remain unclear. This is in particular due to the lack of accurate high throughput cell quantification.In recent years, the 4′,6‐Diamidino‐2‐Phenylindole, Dihydrochloride (DAPI) dye has been used to conduct total cell counts but does not work well with samples taken from the sediment.SYBR Green I is a double stranded DNA specific dye and yields signals with less disturbing background. We have developed a method that combines CARD FISH visualization with SYBR Green I staining and has potential for high throughput quantification to enumerate bacterial clades in the sediment.
Demonstration of a Novel Platform For Measuring Gut Microbiome Metabolic Dynamics
Authors: Wagner David , Bolt Daniel , Demers Melyssa , Gruelich Knut
Published: June 2021

Evaluation of bacterial populations inhabiting the gut microbiome may offer insights to disease development. Further, dietary intake of carbohydrates and a Western diet may shape the metabolic dynamics of the gut microbiome. However, the ability to quantify metabolic dynamics in these bacterial populations is lacking. We developed a stable isotope tracer platform to quantify metabolic pathways based on their ability to produce 13CO2 from various substrates. A model system was first established using Lactobacillus rhamnosus added to a 10 ml Exetainer tube. 13C substates in solution were then added. Samples were heated at 37°C for 4 to 12 hrs. The headspace in each tube was sampled and analyzed by gas isotope ratio mass spectrometry. We demonstrated that 13CO2 production from isotopically enriched solutions of glucose, fructose, acetate, pyruvate, octanoate, oxalate, and urea were able to be quantitated. Samples were tested under both aerobic and anaerobic conditions. Anaerobic conditions produced more 13CO2 gas. L. rhamnosus had limited ability to metabolize amino acids phenylalanine and methionine and other sugars (sorbitol, xylose and lyxose). We then used this technique to quantitate metabolic dynamics in fecal samples. After collection of fecal samples from a healthy individual, approximately 1 ml of diluted fecal samples was added to solutions of 13C‐oxalate and 13C‐urea. Fecal samples were heated at 37°C for 4 to 12 hrs and tested under anaerobic conditions. We demonstrated 13CO2 production from these substrates. When these same fecal samples were left at 22°C for 5 days, the samples continued to show enzymatic conversion to 13CO2. In conclusion, we have demonstrated a simple platform for measuring metabolic dynamics of the gut microbiome in fecal samples.
Cinnamaldehyde Inhibits Biofilm Formation of MRSA
Authors: Rossi Marco , Heuertz Rita
Published: June 2021

NIH identified that 80% of chronic infections are caused by biofilm‐producing bacteria. Of concern is biofilm as a contributory component of antimicrobic resistance: identification of anti‐biofilm agents is necessary and timely. Antibacterial properties are associated with many plant‐derived compounds, such as cinnamaldehyde (derived from cinnamon); however, biofilm effects are not reported. Staphylococcus aureus is known for its multi‐drug resistant strains (MRSA) and plant‐based therapy may be appropriate for these antimicrobic resistant bacteria. Clinical MRSA isolates from area hospital laboratories were assessed for cinnamaldehyde effect using a: (i) microplate assay for quantitative spectrophotometric evaluation of crystal violet‐stained biofilm adherent to microwells; and (ii) standard bacterial count assay for colony forming unit (CFU/ml) enumeration. Results indicated that cinnamaldehyde inhibited MRSA biofilm formation in a concentration‐dependent manner with significance (p<0.01) at 50 and 100 uM. Colony counts of MRSA were also significantly (p<0.01) reduced in a concentration‐dependent manner. Taken together, these results indicate that cinnamaldehyde‐induced killing of MRSA is an important mechanism for inhibition of biofilm formation. Clinical relevance of this study is identification of a plant‐derived compound that inhibits MRSA growth and biofilm formation. Given that cinnamaldehyde has no reported human toxicity and is not cost‐prohibitive, its potential impact is in reduction of MRSA morbidity and mortality.

Financial support for MWR was received from the DeNardo Education and Research Foundation.
Cyclin G2 Contributes to the Cell Cycle Arrest Response of Breast Cancer Cells to Estrogen Signaling‐Antagonists and the AMPK Agonist, Metformin
Authors: Horne Mary , Zimmermann Maike , Arachchige Don Aruni , Donaldson Michaela , Patriarchi Tommaso
Published: June 2021

Resistance to estrogen (E2) receptor (ER) antagonists limits long‐term abatement of ER+ breast cancer (BC). Defining cell cycle control proteins that modify tumor cell resistance to ER‐antagonists tamoxifen and fulvestrant will improve therapeutic approaches. Cyclin G2 (CycG2) is encoded by the ER repressed gene, CCNG2, and upregulated during cell cycle arrest responses to cellular stresses. Here we show that blockade of ER‐signaling enhances the expression and nuclear localization of CycG2 in E2‐dependent BC cell lines. Knockdown of CycG2 in E2‐deprived and fulvestrant‐treated MCF7 cells dampened their cell cycle arrest response. Moreover, loss of CycG2 increases phospho‐activation of MEK1 and inhibition of RB. Our work also indicates that CycG2 forms complexes with the CDK linked to inhibition of tamoxifen resistance and modulation of RAF/MEK/MAPK signaling, CDK10. We reported that signaling through insulin and IGF‐1R receptors strongly represses CycG2 expression. Recent studies suggest the insulin‐sensitizer metformin (MTFN) inhibits BC cell growth by promoting AMPK–mediated suppression of mTOR. Patients taking MTFN exhibit a dose‐dependent reduction in cancer risk. We found that MTFN treatment stimulates CycG2 expression and potentiates fulvestrant‐mediated upregulation of CycG2 and growth arrest of MCF7 cells. Moreover knockdown of CycG2 blunts MTFN‐enhancement of fulvestrant effects. Importantly, analysis of BC tumor microarrays indicates that CCNG2 transcripts are reduced in aggressive, poor‐prognosis BC and that high CCNG2 expression correlates with longer relapse free survival.
Development of a Surface Plasmon Resonance‐Based Assay to Detect Antiproliferative Factor in Interstitial Cystitis Patient Urine
Authors: Chavda Burzin , Ling Jun , Majernick Thomas , Planey Sonia
Published: June 2021

Interstitial cystitis (IC) is a chronic, painful bladder disease that affects mostly women and is frequently misdiagnosed due to lack of a non‐invasive test to detect the disease. Biomarkers for IC have been described, including antiproliferative factor (APF), a sialoglycopeptide that is detectable in the urine of 95‐97% of IC patients vs. normal controls. Validation of APF as a biomarker for IC has been hindered by the absence of robust assays to detect and measure its concentration in patient urine. In this study, we evaluated the utility of surface plasmon resonance (SPR) to detect and quantitate APF in solution through binding to its cellular receptor, cytoskeleton associated protein 4 (CKAP4). Five his‐tagged CKAP4 mutants were designed according to structural predictions in order to optimize the SPR assay. Each purified mutant was immobilized on a CM5 chip through amine‐coupling, and binding activity to APF and as‐APF (a desialylated APF analogue with full activity) was measured. Four of the CKAP4 mutants demonstrated a quantitative binding response to APF and as‐APF, albeit with altered sensitivities; moreover, as‐APF charged to control patient urine could be detected. Future efforts will focus on assay optimization to detect APF in urine from IC patients. USA MED Research ACQ Activity W81XWH‐13‐1‐0454
Spatiotemporal Profiling the Activities of Ectophosphatases on Cancer Cells by Molecular Imaging
Authors: Zhou Jie , Du Xuewen , Shi Junfeng , Xu Bing
Published: June 2021

Ectoenzymes, which have the catalytic domains outside the plasma membrane of cells, usually carry out dual or multiple functions in many types of cells. Despite overexpression of ectophosphatases represents a generic difference between certain cancer and normal cells, the evaluation of their activities is rather difficult and receives little attention. Here we report the use of molecular imaging to profile the activities of ectophosphatases on cancer cells based on enzyme‐catalyzed self‐assembly of a self‐assembling D‐peptide that form fluorescent molecular nanofibrils. Possessing an environment‐sensitive fluorophore and acting as an enzyme substrate, the designed precursor can turn into the corresponding self‐assembling molecules via enzymatic dephosphorylation, which results in the fluorescent nanofibrils that hardly diffuse in cellular environment. Our study reveals the significantly higher activities of ectophosphatases on cancer cells than on stromal cells in co‐culture (Figure 1) and shows an inherent and dynamic difference in phosphatase activities between drug sensitive and resistant cancer cells or between cancer cells with and without hormonal stimulation. Besides providing an approach to achieve high spatiotemporal resolution for profiling the activities of phosphatases, a ubiquitous class of enzymes, in mixed population of live cells, the integration of enzyme catalysis with self‐assembly serves as a novel approach to profile the activities of enzymes and to control the fate of cells
Overweight, Obesity and Cardio‐metabolic Indicators of Peruvian Adolescents Whose Mothers Participated in a Prenatal Zinc Supplementation Trial
Authors: Zavaleta Nelly , Garcia Teresa , Lazarte Fabiola , Caulfield Laura
Published: June 2021

To characterize the nutritional status and cardio‐metabolic indicators of two groups of adolescents 14 yrs old, born from prenatal supplemented mothers. Methods: We evaluated a group of 86 adolescents from mothers that received iron and folic acid (group A), and 75 from mothers that received iron, folic acid and zinc (Group B).

Results

In group A, 16 (18.6%) were overweight and 24.4% were obese; in group B, 15 (20%) were overweight and 16% were obese (NS). Among the overweight and obese children (n=64), mean Hb in group A was 13.5 g/dl and 12.8 g/dl in group B (p=0.007), there were no differences on mean serum zinc, ferritin, PCR, triglycerides, HD cholesterol, glucose, fasting insulin, blood pressure, waist circumference. In group A, 16 (43.2 %), 15 (40.5%) and 5 children (13.5%); in Group B, 13 (48.1%), 8 (29.6%) and 3 children (11.1%) had 1, 2 and 3 or more abnormal cardio metabolic indicators (NS). In 53 (82.8%) children had PCR > 5mg/L, in 56 (87.5%) had HDL cholesterol < 40 mg/dl (NS between groups). Results have shown a high prevalence of overweight and obesity in this population, cardio‐metabolic indicators shown a trend to develop metabolic syndrome. Differences were not associated to group of maternal supplementation. Supported by Nestle Foundation.
Associations of Community‐Level Sanitation and Child Stunting in Bengali and Tribal Populations in Bangladesh: A Cross‐Sectional Study
Authors: Sinharoy Sheela , Waid Jillian , Stein Aryeh
Published: June 2021

Objective

To describe trends and determinants of stunting prevalence among tribal and Bengali children in the Chittagong Hill Tracts of Bangladesh.

Methods

We analyzed surveillance data collected from 2003 – 2006 among 12,006 children aged 6‐23 months.

Results

Mean height‐for‐age z‐score (HAZ) was stable for Bengali children (‐1.88 in 2003 to ‐1.90 in 2006) but increased for tribal children (‐1.87 in 2003 to ‐1.68 in 2006). The difference between groups was significant in 2005 (p=0.0017) and 2006 (p=0.0014). In both groups, HAZ was negatively associated with age in months (p=0.001) and distance to health center (p=0.039) and positively associated with mother's height (p=0.012). HAZ was also positively associated with father's schooling (p=0.009) among Bengali children and with consumption of animal source foods (p=0.007) and goat ownership (p=0.045) among tribal children, and negatively associated with village‐level prevalence of open defecation among tribal children (p=0.022). Blinder‐Oaxaca decomposition demonstrated a significant difference in pooled coefficients between the two groups (p=0.003). This was explained primarily by village‐level open defecation, which was significant only for tribal children (p=0.018).

Conclusions

Village‐level prevalence of open defecation is an important explanatory factor for the difference in HAZ between tribal and Bengali populations. Open defecation may also act a proxy for unmeasured factors such as household environmental conditions and food hygiene.

Source of Research Support

Laney Graduate School (Emory University) and HKI
Predictors of Undernutrition and Stunting Among Adolescents in Tanzania: a Rural/Urban Comparison
Authors: Otis N , Nelson‐Peterman J , Cordeiro L
Published: June 2021

Adolescents remain one of the world's most neglected, difficult to measure, and hard to reach populations. Sub‐Saharan Africa is the only region in the world where the adolescent population continues to grow relative to the total population, and where prevalence rates of malnutrition remain stagnant. This cross‐sectional study examined data on adolescents (10‐14 yrs; n=1125) in Tanzania. Undernutrition was classified as BMI for age <‐2SD and stunting was classified as height‐for‐age <‐2SD using WHO 2007 reference. Multivariate linear regression analysis tested associations between urban/rural residence and BMIZ, as well as HAZ. Prevalence of undernutrition was 10.9% among rural and 6.2% among urban adolescents (p<0.05). Stunting was prevalent in 64.2% of rural and 3.9% of urban adolescents (p<0.05). Significant predictors of BMIZ were gender, child age, urban/rural status, and number of assets owned (p<0.001). Significant predictors of HAZ were identical but included ownership of a modern floor (p<0.001). BMIZ was 0.41 units lower in rural adolescents (p<0.001), and HAZ was 2.025 units lower in rural adolescents (p<0.001), when all other covariates were identical. Our findings suggest that adolescents in rural settings experience higher rates of undernutrition and stunting than urban youth. Longitudinal studies are needed to determine whether adolescent nutritional status in developing countries has a physiological explanation and whether growth trajectories differ across urban/rural settings. Policies directed at improving the nutritional status and health of adolescents should be concurrent with those directed at improving morbidity and mortality outcomes in children under five years.
Child‐level dual burden of malnutrition in the MENA and LAC regions: prevalence and predictors
Authors: Ghattas Hala , Acharya Yubraj , Assi Moubadda , El Asmar Khalil , Jones Andrew
Published: June 2021

Whilst the prevalence of obesity has rapidly increased in the Middle East and North Africa (MENA) and Latin America and the Caribbean (LAC) regions, child undernutrition remains a public health challenge. We examined region‐specific sociodemographic determinants of the co‐occurrence of within‐child stunting and overweight using the most recent Demographic and Health Survey (DHS) and Multiple Indicator Cluster Survey (MICS) data (2004‐2013) from 8 countries in the MENA (n=103,879) and 8 countries in the LAC (n=49,918) regions. We used multiple logistic regression to model country‐ and region‐specific associations of sex, maternal education, household wealth, and area of residence with stunting, overweight and the co‐occurrence of within‐child stunting and overweight in children aged 6‐59 months. The prevalence of stunting, overweight, and their co‐occurrence within children in the MENA and LAC regions respectively, were 21% and 17%; 12% and 6.9%; and 6.1% and 1.3%. In both regions, higher maternal education and household wealth were associated with lower odds of stunting and higher odds of overweight. Post‐secondary education among mothers (OR (95% CI): 0.62 (0.43, 0.90)) and greater household wealth (0.52 (0.30, 0.90)) were associated with a lower odds of concurrent child stunting and overweight in the LAC region but not the MENA region. Stunted‐overweight children were more likely to be boys in both regions. There was no association between rural/urban residence and any nutritional outcomes in either region. Child stunting and overweight coexist throughout the MENA and LAC regions, and cross urban/rural and sociodemographic divides.
Overweight is Prevalent among Cameroonian Women and is Associated with Increased Waist Circumference, Region, and Household Characteristics
Authors: Engle‐Stone Reina , Nankap Martin , Ndjebayi Alex , Friedman Avital , Tarini Ann , Brown Kenneth
Published: June 2021

We examined the prevalence of overweight and obesity, and associated household and dietary risk factors, in a national sample of Cameroonian women and children, and the change in these values within urban areas after 3 y.

In a 2009 national survey (3 strata: South, North, Yaoundé/Douala, 30 clusters/stratum, 10 households/cluster), information on dietary intake, household characteristics, and height/length and weight were obtained from women 15‐49 y and children 12‐59 mo. A 2012 study in Yaoundé/Douala surveyed the same 30 clusters; in addition to the above measures, women's waist and hip circumferences were measured.

In 2009, 32% of non‐pregnant women had BMI 蠅 25.0 and 11% of women had BMI 蠅 30. Prevalence of BMI 蠅 25 differed among regions (40% South, 11% North, 48% Yaoundé/Douala), but not between urban and rural areas (36 vs 27%, P=0.11). Greater maternal age, TV ownership, and, in the North, socio‐economic status, were associated with BMI 蠅 25. Weight‐for‐height Z score > 2SD among children was < 4% in all regions. Mean BMI among women in Yaoundé/Douala was 26.0 and 26.9 kg/m2 and BMI 蠅 25 was 48% and 57%, respectively, in 2009 and 2012 (P > 0.1). Overweight/obese women had greater waist‐to‐hip ratios and were more likely to have waist circumference > 88 cm compared to women with BMI < 25 (P < 0.001).

The results indicate that overweight/obesity is prevalent among women in some regions of Cameroon. A comprehensive public health strategy is needed to combine chronic disease prevention with efforts to address micronutrient deficiencies and infectious diseases.
Maternal Glycemia and Preterm Birth in the PRECONCEPT Cohort in Vietnam
Authors: Ford Nicole , Nguyen Phuong , Ramakrishnan Usha , Martorell Reynaldo
Published: June 2021

Objective

Studies on gestational glycemia have focused primarily on developed country and predominantly overweight populations. Despite low prevalence of traditional risk factors, Vietnamese women have a high burden of gestational diabetes. Our study examined the role of maternal hyperglycemia in predicting preterm birth in rural Vietnam.

Methods

The PRECONCEPT study recruited women pre‐pregnancy for a randomized micronutrient intervention with prospective data collection through delivery. This analysis is based on a sub‐sample of the cohort with complete information on gestational age and maternal glycemia (N=975). Maternal hyperglycemia was defined as fasting blood glucose 蠅5.1 mmol/L at 23‐28 weeks gestation. Multivariate logistic models assessed the role of maternal hyperglycemia in predicting preterm birth (<37 weeks) and explored predictors of maternal glycemia.

Results

Overall, 46.1% of women had hyperglycemia, and 8.7% had a preterm birth. Maternal hyperglycemia was not associated with preterm birth (RR 0.84; 95% CI 0.53‐1.32). None of the candidate predictors of maternal hyperglycemia, including parity, pre‐pregnancy BMI, gestational weight gain, and physical activity were significant in multivariate analyses (p>.05).

Conclusion

While 46% of women had maternal hyperglycemia, it was not associated with risk of preterm. We were unable to identify risk factors for maternal hyperglycemia, suggesting that universal screening may be required. Future work is needed to examine potential consequences of maternal hyperglycemia for women and their offspring in this population and better define the public health significance of this condition in Vietnam.
Prevalence and Associated Factors of Malnutrition Among Primary School Students in the Rakai District of Uganda
Authors: Brown Erika , Kern Mark
Published: June 2021

Anthropometric measurements are used to identify three key markers of malnutrition in children. These measures can be compared to the World Health Organization (WHO) growth reference standards for children 5‐19 years old. The purpose of this study was to use anthropometry to determine prevalence of stunting, underweight, and wasting in students at a boarding school in rural Southern Uganda. This was a cross‐sectional descriptive study of the nutrition status of 320 students. Prevalence of stunting, underweight and wasting were determined by calculating height‐for‐age (HAZ), weight‐for‐age (WAZ), and BMI‐for‐age Z‐scores, respectively. These factors of malnutrition were then tested for associations with age, gender and residency status of the students. The prevalence of stunting was 26.6%; underweight was 12.8% and wasting was 3.8%. Overall, the average HAZ and WAZ scores for the total population were ‐1.26 (1.15) and ‐1.37 (1.01), respectively, indicating mild malnutrition across the population. Results of the chi‐square tests revealed prevalence of stunting was dependent on age group and a greater number of children in the younger age group were stunted compared to the older age group. No other significant associations were found between malnutrition factors and gender or residency status. Malnutrition is prevalent among the school children in the Rakai District of Uganda, with stunting affecting a higher percentage of the children than underweight or wasting. Additionally, age significantly influenced stunting prevalence in the study population.
Relationship of Feeding Human Milk by Breast Versus Bottle with Infant Growth
Authors: Wilson Kelsey , Lovelady Cheryl
Published: June 2021

Research suggests that infants fed human milk from a bottle versus the breast may have higher weight gains in the first 6 to 12 months of life. The purpose of this study was to determine if infants fed human milk directly from the breast differed in growth and adiposity measurements compared to those fed human milk from the bottle. Infant's weight, length, and tricep and subscapular skinfold thickness were measured at 2 and 4 months. Mothers reported birth weight and length and completed monthly questionnaires on infant feeding practices (e.g., number of human milk feedings by bottle or breast per day, age of introduction to complementary foods, and infant bottle‐emptying behavior). Infants were placed into 2 groups based on their reported mode of feeding at 3 months: Nursing Group (NG, n=15), infants fed predominantly at the breast with less than 25% of the feeds from a bottle and Bottle Group (BG, n=10), infants fed human milk from the bottle more than 25% of the feeds. Change in BMI Z scores from 2 to 4 months were significantly different between groups (NG=‐0.18 ± 0.67 vs BG=0.48 ± 0.73, p=0.03). Changes in skinfold thickness from 2 to 4 months were not statistically different between groups. Weight gain velocity from 2 to 4 months was compared to WHO weight velocity standards. Only 3 infants in each group exceeded the 75th percentile for weight gain velocity. The majority of parents reported those infants fed human milk from the bottle finished the bottle “most of the time” or “all of the time.” None of the infants were introduced to complementary foods before 4 months. The results of this study suggest that bottle‐feeding human milk may be related to differences in weight gain during 2 to 4 months. However, follow up for a longer time period with a larger sample size is necessary to fully investigate the relationship of bottle‐feeding with infant growth.
A Case‐Control Study of Diabetes during Pregnancy and Low Milk Supply
Authors: Nommsen‐Rivers Laurie , Riddle Sarah
Published: June 2021

Low milk supply is one of the most common reasons for stopping breastfeeding. Correlates of glucose intolerance are risk factors for delayed secretory activation, but it is not known if glucose intolerance is associated with persistent low milk supply. Our objective was to determine whether exposure to diabetes in pregnancy is greater among women with low milk supply as compared to women with latch problems in a Breastfeeding Medicine Clinic (BMC). We conducted a case‐control analysis of electronic medical records. We defined cases as low milk supply, but without latch or nipple problem; and controls as latch or nipple problem without low milk supply. We calculated odds of exposure to diabetes in cases versus controls in an unadjusted model and after adjusting for covariates (maternal and infant age, Cesarean delivery, preterm birth) and comorbidities (PCOS, hypothyroid or infertility). After excluding 74 with dual diagnoses, 14.9% of cases (26/175) versus 6.2% of controls (14/226) were exposed to diabetes (OR [95%CI], 2.6[1.3‐5.2]), a relation that remained robust after adjustment for covariates and comorbidities (AOR [95%CI], 2.4[1.2‐4.9]). Thus, women with low milk supply were significantly more likely to have been exposed to diabetes than those with latch or nipple problems. Identification of physiologic parameters that underlie the association between glucose intolerance and low milk supply is needed to enable more effective therapy options.
Beliefs Regarding Lactation Success among Mothers on a University Campus
Authors: Dinour Lauren , Bai Yeon
Published: June 2021

The purpose of this study is to characterize the beliefs of university‐affiliated women regarding pumping breast milk on campus. Using convenience sampling, women were recruited via e‐mail, social media, and posted fliers. Semi‐structured interviews were conducted to elicit respondents' behavioral, normative, and control beliefs regarding pumping on campus. Two researchers independently coded and categorized responses based on common themes, and response frequencies were calculated and compared between employees and students. Thirty‐two women (21 employees, 11 students) participated in the interview. Both groups of women most often reported that maintaining milk supply/extending breastfeeding duration was an advantage to pumping on campus. Employees most frequently identified time/scheduling issues as a disadvantage to pumping on campus, while students more often reported mother's discomfort as a disadvantage. Peers and mothers were the most commonly perceived supporters among employees and students, respectively. On the other hand, employees most commonly perceived those who are unaware, uninformed, and/or disapproving of breastfeeding as opponents to pumping on campus, while students most frequently identified superiors (instructors, professors) as oppositional. Regarding control beliefs, students most frequently identified lack of available pumping space as a barrier, while employees most often reported that space availability was a facilitator to pumping on campus. Both employees and students also frequently stated that scheduling and time constraints were a pumping barrier. These results suggest that universities can do more to support all women who wish to continue a breastfeeding relationship while at work or school. Employees and students have common and unique pumping needs that warrant further examination.
Influences on Breastfeeding Exclusivity and Duration
Authors: Wells Jody , Virmani Misty , Crook Tina , Phelps Josh , Hakkak Reza
Published: June 2021

Breastfeeding is the natural and medically optimal method of human infant feeding. Efforts to understand the factors associated with successful breastfeeding are vitally important to the medical community. The purpose of this study was to determine which factors have the strongest influence on breastfeeding duration and breast milk exclusivity. A questionnaire was administered to 114 breastfeeding mothers who elected to initiate breastfeeding after delivery at the University of Arkansas for Medical Sciences Hospital. Outcome measures included number of days infant breastfed, whether they were exclusively breastfed or supplemented with formula, if mothers had social support, the level of perceived medical support, if mothers had previous experience with breastfeeding, and if mothers received breastfeeding education prior to delivery.Significant correlations were found between breastfeeding duration and both previous breastfeeding experience and higher perceived quality of medical support for breastfeeding. Logistic regression showed that social support had an OR = 16.721 related to breast milk exclusivity. Significant correlations were also found between breast milk exclusivity and both maternal race and personal breastfeeding experience. Our findings suggested that social support and previous breastfeeding experience were the best predictors of breast milk exclusively and duration. The results of this study will help guide efforts to improve breastfeeding duration rates and social image of the breastfeeding method.
Filling the Gap: Trends in and Factors Related to Infant Feeding Choice in the U.S. from 1925‐1964
Authors: Pilles K , Dong YQ , Willett WC , Michels KB , Forman MR
Published: June 2021

Identifying infant feeding (IF) practices of the mothers of the nurse daughters in the Nurses' Health Cohort Studies provides early life data to link to the daughter's adult disease risk.

The objective is to describe the rates of exclusive breastfeeding (XBR); of ever breastfeeding i.e. XBR plus breast and bottle‐feeding (Ever BR); and of exclusive bottle‐feeding (XBot) from 1925‐1964; and to identify the factors influencing IF choice by birth cohort via a retrospective cohort in the Nurses' Health Cohort Studies (N= 39,743). Multiple logistic regression analysis was used to calculate the adjusted odds ratios for Ever BR and XBR.

80% of mothers in the Great Depression Ever BR and this rate steadily declined to 37% in 1964. A declining trend also appeared in XBR from 41% to 10%. Factors positively associated with Ever BR were: any maternal college education compared to <12 years of education and delivering a low or high compared to normal birth weight nurse daughter. Factors negatively associated with Ever BR were: smoking during pregnancy, C‐section delivery, pre‐term births, birth orders 2+, and nurse daughters born after 1939. Factors differed for birth cohort specific models, e.g. maternal age was associated with XBR during the Great Depression, while maternal education was associated with XBR from the 1950's on. Among the XBot, the majority used canned evaporated milk until 1959 and then switched to infant formula. Obesity prior to and weight gain during pregnancy were not related to IF choice in contrast with determinants of today.

The Nurses' Mother's Cohort Study fills a gap in rates of and factors influencing IF choice in the U.S. from 1925‐1964. Our results are birth cohort era specific and differ with current determinants.
Mothers' Experiences Expressing Breastmilk for VLBW Infants: A Phenomenological Case Study
Authors: Bower K , Burnette T , Lewis D , Wright C , Kavanagh K
Published: June 2021

The purpose of this phenomenological study was to gain an understanding of mothers' experiences expressing breastmilk for their very‐low‐birth‐weight (VLBW) infants in a Level III Neonatal Intensive Care Unit (NICU). Using purposive sampling, mothers with VLBW infants in the NICU were invited to participate if they had ever expressed breastmilk during their infant's stay. Mothers were eligible if they were English‐speaking, 18 years or older, maintaining custody post discharge, and their breastmilk was not contraindicated for any reason. In‐depth, semi‐structured interviews were conducted in person in a private room at the NICU or over the phone, per the mother's preference. Consistent with phenomenological methods, interviews began with the question: “tell me about your experience pumping breastmilk for your baby.” Additional questions prompted for further detail to better capture the mother's experiences. All interviews were audio‐recorded, transcribed verbatim, and analyzed using Colaizzi's methodology. To date, 11 mothers have consented and been interviewed. Results are based on preliminary findings from these first interviews. Emergent themes related to expressing breastmilk include: 1) breastmilk has more benefits than formula for NICU infants; 2) mothers can actively participate in infants' care; 3) pumping is time consuming; and 4) ease of formula‐feeding may influence mothers to quit pumping. Data analysis will continue until saturation has been achieved. Mothers will be re‐contacted to validate the researchers' interpretations or the results. Results will be used to inform development of a pilot intervention to promote breastmilk expression in the NICU setting.

Funding: Univ. of TN, Professional Development Fund
“Las Dos Cosas” on the U.S.‐México Border
Authors: Anchondo Ines , Flores Angela , Huang Cindy , Finch Casey
Published: June 2021

Objective

Determine breastfeeding barriers on the U.S‐México border (El Paso, Texas), with high breastfeeding initiation (84%, hospital discharge), but low duration (16%, 3 months after delivery).

Methods: 300 mostly Mexican‐American low‐income mothers answered a 14‐question survey about infant feeding, socio‐demographics, and health habits.

Results: Breastfeeding barriers included deciding to breastfeed and formula feed (72%) or do “las dos cosas” after delivery. Only 61 mothers (20%) chose exclusive breastfeeding and 22 mothers (7%) chose exclusive formula feeding after delivery. Although new mothers were educated about breastfeeding, 32% still chose to formula feed in the immediate postpartum period. Multiple regression analysis showed barriers to breastfeeding included deciding during pregnancy not to exclusively breastfeed and not having breastfed previous children. Other barriers included not having enough breast milk (33%), planning to go back to work or school (17%), and not having a female relative to provide support. Acculturation did not play a role in breastfeeding decision. The ‘any’ breastfeeding rate was 94% and exclusive breastfeeding rate was 22%.

Conclusion

Mexican‐American mothers who decide to breastfeed during pregnancy or have breastfed other children are more likely to choose exclusive breastfeeding after delivery. Official breastfeeding rates for Mexican‐American mothers are misleading, because although these mothers' breastfeeding initiation is high, many begin to offer formula immediately after birth. This practice of “las dos cosas” must be considered when providing breastfeeding support to these mothers.

Research support: Texas Tech University Health Sciences Center ‐ Pediatrics
Obese Mothers Have a Lower Prevalence of Exclusive Breastfeeding<6 Mo as Compared to Non‐Obese Mothers: Data From the 2012 National Health and Nutrition Survey
Authors: Gonzalez de Cosío Teresita , Escobar Leticia , González‐Castell Luz Dinorah
Published: June 2021

Objective

To estimate the prevalence of exclusive breastfeeding <6 mo (EBF<6m) by level of obesity in Mexican women who participated in the 2012 National Nutrition Survey.

Methods: A representative sample of 477 postpartum women 12‐49 y and their <6 mo infants were studied. EBF<6m information obtained by status quo method; EBF<6mo indicator was constructed as recommended by the WHO‐2008. Maternal weight and height were measured wearing light clothing ‐ no shoes. Maternal BMI (kg/m2) categorized in non‐obese, obese‐1 or obese‐2+ (BMI<30, 30‐< 35 and 35+ respectively). To compare proportions of EBF< 6m per BMI we used Student's t test and the Mann‐ Kendall test for trend. P < 0.05 was declared statistically significant.

Results: Prevalence of EBF<6m was 17.4, 7.1 and 3.2 % in non‐obese, obese‐1 and obese‐2+ women respectively (p< 0.05 for proportions, p=0.012, test for trend). Results are similar when excluding teenage mothers from the analysis.

Conclusion

Obesity inhibits breastfeeding through an inadequate prolactin response to suckling, which in turn associates with delayed onset lactogenesis II, hindering the establishment of successful breastfeeding in obese mothers. Results of this study derived from nationally representative data show that the risk of inadequate breastfeeding is significantly higher in obese women, and this risk increases with increasing obesity. The information is alarming given the current obesity pandemic concurrent with the declining prevalence of breastfeeding in Mexico.

Funded by the National Institute of Public Health, Mexico
Branch Chain Fatty Acids of Human Milk: Influenced by Maternal Diet?
Authors: Dingess K , Valentine C , Davidson B , Peng Y , Guerrero M L , Ruiz‐Palacios G , Ollberding N , Summer S , Ward D , Newburg D , Brenna J T , McMahon R , Morrow A
Published: June 2021

Human milk (HM) fatty acid (FA) composition differs between mothers. The FA of HM include branched chain fatty acids (BCFA). HM BCFA may be influenced by maternal consumption of ruminant products; data are lacking. We examined BCFA concentrations in HM from 3 urban populations with differing diets: Cincinnati, Shanghai and Mexico City. Sample collection was standardized as part of the GEHM study. Enrollment was limited to healthy mothers of term, singleton infants. FA were extracted from milk using Bligh‐Dyer and analyzed by gas chromatography. Dietary analysis included three 24 hour dietary recalls, limited to Cincinnati mothers. Statistical analysis was done using ANOVA. Samples from ~115 women were analyzed per site at postpartum week 4. Cincinnati, Shanghai and Mexican mothers, respectively, had mean age in years of 32, 29, and 25; prepregnancy BMIs of 28, 21, and 24; and parity of 2, 1, and 2. The BCFA iso14:0, iso16:0, iso18:0, iso20:0, anteiso15:0, anteiso17:0 all differed in concentration (p<0.0001) among cohorts. With linear regression of BCFA, site differences persisted after controlling for delivery mode, maternal age and BMI. Intake of dairy was associated with iso14:0, anteiso15:0 and iso16:0 but not the longer BCFA. Beef intake was not associated with any BCFA. The BCFA intake of breastfed infants differs significantly worldwide; its significance requires investigation.
Milk Mineral and Cytokine Concentrations Differ in Guatemalan Mothers with Subclinical Mastitis (SCM) by Stage of Lactation
Authors: Li Chen , Wren Hilary , Solomons Noel , Scott Marilyn , Koski Kristine
Published: June 2021

Background

Little is known about the impact of SCM on the immunological and mineral concentrations of human breast milk. Our objective was to determine if minerals and cytokines differed in mothers with and without SCM during 3 stages of lactation.

Methods

Transitional milk (TM: 5‐17d, n=21), early mature milk (EMM: 18‐46d, n=32) and mature milk (MM: 109‐187d, n=59) samples were collected from Mam‐Mayan women. Inductively Coupled Plasma Mass Spectrometry was used to analyze the concentration of 13 minerals (Na, K, Ca, Mg, Mn, Zn, Cu, Cr, Sr, Se, Rb, Fe, P) and immunoassay with Luminex was used to determine the concentration of 4 cytokines (IL‐1β, IL‐6, IL‐8, TNF‐α).

Results

Prevalences of SCM, using Na/K > 0.6, were 26.3% in TM, 15.6% in EMM and 8.9% in MM. Na, K, P, Cu, Fe, Rb, Zn and IL6 were higher in TM and EMM whereas Mg was higher in MM, as was IL‐8. SCM was associated with changes in P and Se and with the presence of 3 cytokines (IL‐6, IL‐8, and TNF‐α) in TM only. Regression analyses for each mineral showed that cytokines were associated with higher milk mineral concentrations: IL‐1β with P, Fe and Mn; IL‐6 with Na, K, Ca and Cu; IL‐8 with Zn; and TNF‐α with Na, Mn and Se.

Conclusion

Milk minerals and cytokines concentrations vary by lactation stages. The cytokines are associated with changes in milk mineral concentrations. Our finding suggests that IL‐6 is associated with elevated Na/K ratio.

Funding

McGill University International Mobility Award
Effect of Breastmilk Leptin and Macronutrient Content on Gastric Emptying in Term Breastfed Infants
Authors: Geddes Donna , Gridneva Zoya , Cannon Anna , Hepworth Anna , Tie Wan , Lai Ching , Hartmann Peter
Published: June 2021

Higher breastmilk casein concentration increases gastric emptying in preterm infants, however there are limited information regarding whether casein or other components of breastmilk affect gastric emptying in term infants. In this study we investigated associations of macronutrient and skim milk leptin concentrations with gastric emptying.

Term fully breastfed infants (n=20, aged 6 to 32 weeks) were examined with ultrasound before and after one feed, and then at 10‐20 minute intervals until the next feed. Stomach volumes were calculated from transverse and sagittal ultrasound scans of the infant stomach. Milk intake was measured by the test‐weigh method. Breastmilk samples (1‐2 mL) were collected and analyzed for fat, lactose, total protein, whey and casein protein and skim milk leptin. Leptin dose was calculated as an average concentration multiplied by the feed volume

After accounting for the total feed volume and the time since the end of the feed post‐feed stomach volumes were not associated with leptin dose (P=0.998), leptin (P=0.91), fat (P=0.78), protein (P=0.80), whey (P=0.15), casein (P=0.37) or lactose (P=0.59) concentrations. Leptin dose was positively associated with protein (P<0.001) but not with fat (P=0.58), whey (P=0.76), casein (P=0.75) or lactose (P=0.77) concentration after accounting for the total feed volume.

Gastric emptying in term infants does not appear to be affected by milk composition in the same way that it is in preterm infants.