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1.
Soc Sci Med ; 347: 116694, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38569315

ABSTRACT

PURPOSE: As wellbeing is culturally bound, wellbeing measures for Aboriginal and Torres Strait Islander peoples must be culturally relevant and grounded in Aboriginal and Torres Strait Islander values and preferences. We describe the development of a nationally-relevant and culturally grounded wellbeing measure for Aboriginal and Torres Strait Islander adults: the What Matters to Adults (WM2A) measure. METHODS: We used a mixed methods approach to measure development, combining Indigenist methodologies and psychometric methods. Candidate items were derived through a large national qualitative study. Think-aloud interviews (n = 17) were conducted to assess comprehension, acceptability, and wording of candidate items. Two national surveys collected data on the item pool (n = 312, n = 354). Items were analysed using exploratory factor analysis (EFA), and item response theory (IRT) to test dimensionality, local dependence and item fit. A Collaborative Yarning approach ensured Aboriginal and Torres Strait Islander voices were privileged throughout. RESULTS: Fifty candidate items were developed, refined, and tested. Using EFA, an eight factor model was developed. All items met pre-specified thresholds for maximum endorsement frequencies, and floor and ceiling effects; no item redundancy was identified. Ten items did not meet thresholds for aggregate adjacent endorsement frequencies. During Collaborative Yarning, six items were removed based on low factor loadings (<0.4) and twelve due to conceptual overlap, high correlations with other items, endorsement frequencies, and/or low IRT item level information. Several items were retained for content validity. The final measure includes 32 items across 10 domains (Balance & control; Hope & resilience; Caring for others; Culture & Country; Spirit & identity; Feeling valued; Connection with others; Access; Racism & worries; Pride & strength). CONCLUSIONS: The unique combination of Indigenist and psychometric methodologies to develop WM2A ensures a culturally and psychometrically robust measure, relevant across a range of settings and applications.


Subject(s)
Australian Aboriginal and Torres Strait Islander Peoples , Health Services, Indigenous , Adult , Humans , Emotions , Factor Analysis, Statistical , Indigenous Peoples , Psychometrics
2.
Sci Rep ; 14(1): 7810, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38565914

ABSTRACT

It is often assumed that future coastal cliff retreat rates will accelerate as global sea level rises, but few studies have investigated how SLR (sea level rise) might change cliff-front wave dynamics. Using a new simple numerical model, this study simulates the number and type (breaking, broken, or unbroken) of cliff-front waves under future SLR scenarios. Previous research shows breaking waves deliver more energy to cliffs than broken waves, and unbroken waves generate minimal impact. Here, we investigated six cliff-platform profiles from three regions (USA, New Zealand, and UK) with varied tidal ranges and wave climates. Model inputs included 2013-2100 hindcast/forecast incident wave height and tidal water level, and three future SLR scenarios. Results show the number of both cliff-front breaking and broken waves generally increase for a high-elevation (relative to tide) cliff-platform junction. In contrast, breaking/broken wave occurrence decrease by 38-92% for a near-horizontal shore platform with a low-elevation cliff-platform junction under a high SRL scenario, leading to high (96-97%) unbroken wave occurrence. Overall, results suggest the response of cliff-front waves to future SLR is complex and depends on shore platform geometries and SLR scenarios, indicating that future cliff retreat rates may not homogeneously accelerate under SLR.

4.
Commun Biol ; 6(1): 449, 2023 04 24.
Article in English | MEDLINE | ID: mdl-37095203

ABSTRACT

Complex and irregular cell architecture is known to statistically exhibit fractal geometry, i.e., a pattern resembles a smaller part of itself. Although fractal variations in cells are proven to be closely associated with the disease-related phenotypes that are otherwise obscured in the standard cell-based assays, fractal analysis with single-cell precision remains largely unexplored. To close this gap, here we develop an image-based approach that quantifies a multitude of single-cell biophysical fractal-related properties at subcellular resolution. Taking together with its high-throughput single-cell imaging performance (~10,000 cells/sec), this technique, termed single-cell biophysical fractometry, offers sufficient statistical power for delineating the cellular heterogeneity, in the context of lung-cancer cell subtype classification, drug response assays and cell-cycle progression tracking. Further correlative fractal analysis shows that single-cell biophysical fractometry can enrich the standard morphological profiling depth and spearhead systematic fractal analysis of how cell morphology encodes cellular health and pathological conditions.


Subject(s)
Lung Neoplasms , Humans
5.
Comput Struct Biotechnol J ; 21: 1598-1605, 2023.
Article in English | MEDLINE | ID: mdl-36874160

ABSTRACT

Current single-cell visualisation techniques project high dimensional data into 'map' views to identify high-level structures such as cell clusters and trajectories. New tools are needed to allow the transversal through the high dimensionality of single-cell data to explore the single-cell local neighbourhood. StarmapVis is a convenient web application displaying an interactive downstream analysis of single-cell expression or spatial transcriptomic data. The concise user interface is powered by modern web browsers to explore the variety of viewing angles unavailable to 2D media. Interactive scatter plots display clustering information, while the trajectory and cross-comparison among different coordinates are displayed in connectivity networks. Automated animation of camera view is a unique feature of our tool. StarmapVis also offers a useful animated transition between two-dimensional spatial omic data to three-dimensional single cell coordinates. The usability of StarmapVis is demonstrated by four data sets, showcasing its practical usability. StarmapVis is available at: https://holab-hku.github.io/starmapVis.

6.
Am J Orthopsychiatry ; 93(3): 236-244, 2023.
Article in English | MEDLINE | ID: mdl-36931837

ABSTRACT

Using models of risk and resilience as a guide, this study examined the mediating role of constructive conflict behaviors on the associations between maternal depressive symptoms, intimate partner violence (IPV), and child behavior problems. The nature of the mediation pathways was also examined for two groups of families, one experiencing high and another experiencing low levels of partner social support. Participants included 196 mothers and their preschool-aged children from diverse ethnic and socioeconomic backgrounds in Guyana. Constructive conflict behaviors partially mediated the link between maternal depressive symptoms and children's externalizing behaviors. Maternal depressive symptoms and physical intimate partner violence were directly related to children's internalizing behaviors. Constructive conflict behaviors were not a mediator of the association between risk factors and children's behavioral outcomes for families experiencing high or low levels of partner social support. In the context of families experiencing high partner social support, constructive conflict behaviors appeared to be more effective in reducing children's externalizing problem behaviors. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Subject(s)
Intimate Partner Violence , Problem Behavior , Child, Preschool , Female , Humans , Child , Guyana , Depression , Mothers
7.
Lab Chip ; 23(5): 1011-1033, 2023 03 01.
Article in English | MEDLINE | ID: mdl-36601812

ABSTRACT

Propelled by the striking advances in optical microscopy and deep learning (DL), the role of imaging in lab-on-a-chip has dramatically been transformed from a silo inspection tool to a quantitative "smart" engine. A suite of advanced optical microscopes now enables imaging over a range of spatial scales (from molecules to organisms) and temporal window (from microseconds to hours). On the other hand, the staggering diversity of DL algorithms has revolutionized image processing and analysis at the scale and complexity that were once inconceivable. Recognizing these exciting but overwhelming developments, we provide a timely review of their latest trends in the context of lab-on-a-chip imaging, or coined optofluidic imaging. More importantly, here we discuss the strengths and caveats of how to adopt, reinvent, and integrate these imaging techniques and DL algorithms in order to tailor different lab-on-a-chip applications. In particular, we highlight three areas where the latest advances in lab-on-a-chip imaging and DL can form unique synergisms: image formation, image analytics and intelligent image-guided autonomous lab-on-a-chip. Despite the on-going challenges, we anticipate that they will represent the next frontiers in lab-on-a-chip imaging that will spearhead new capabilities in advancing analytical chemistry research, accelerating biological discovery, and empowering new intelligent clinical applications.


Subject(s)
Deep Learning , Microscopy/methods , Lab-On-A-Chip Devices , Image Processing, Computer-Assisted , Oligonucleotide Array Sequence Analysis
8.
Nat Commun ; 14(1): 508, 2023 01 31.
Article in English | MEDLINE | ID: mdl-36720884

ABSTRACT

Global environmental change is identified as a driver of physical transformation of coral reef islands over the past half-century, and next 100 years, posing major adaptation challenges to island nations. Here we resolve whether these recent documented changes in islands are unprecedented compared with the pre-industrial era. We utilise radiometric dating, geological, and remote sensing techniques to document the dynamics of a Maldivian reef island at millennial to decadal timescales. Results show the magnitude of island change over the past half-century (±40 m movement) is not unprecedented compared with paleo-dynamic evidence that reveals large-scale changes in island dimension, shape, beach levels, as well as positional changes of ±200 m since island formation ~1,500 years ago. Results highlight the value of a multi-temporal methodological approach to gain a deeper understanding of the dynamic trajectories of reef islands, to support development of adaptation strategies at timeframes relevant to human security.


Subject(s)
Acclimatization , Asian People , Humans , Coral Reefs , Geology
10.
Lab Chip ; 20(20): 3696-3708, 2020 10 21.
Article in English | MEDLINE | ID: mdl-32935707

ABSTRACT

The association of the intrinsic optical and biophysical properties of cells to homeostasis and pathogenesis has long been acknowledged. Defining these label-free cellular features obviates the need for costly and time-consuming labelling protocols that perturb the living cells. However, wide-ranging applicability of such label-free cell-based assays requires sufficient throughput, statistical power and sensitivity that are unattainable with current technologies. To close this gap, we present a large-scale, integrative imaging flow cytometry platform and strategy that allows hierarchical analysis of intrinsic morphological descriptors of single-cell optical and mass density within a population of millions of cells. The optofluidic cytometry system also enables the synchronous single-cell acquisition of and correlation with fluorescently labeled biochemical markers. Combined with deep neural network and transfer learning, this massive single-cell profiling strategy demonstrates the label-free power to delineate the biophysical signatures of the cancer subtypes, to detect rare populations of cells in the heterogeneous samples (10-5), and to assess the efficacy of targeted therapeutics. This technique could spearhead the development of optofluidic imaging cell-based assays that stratify the underlying physiological and pathological processes based on the information-rich biophysical cellular phenotypes.


Subject(s)
Deep Learning , Biophysics , Flow Cytometry , Image Cytometry , Phenotype
11.
Int J Biol Macromol ; 163: 833-841, 2020 Nov 15.
Article in English | MEDLINE | ID: mdl-32653378

ABSTRACT

The study of the experimental and calculated heat capacity, Cp of fish collagen (silver carp) with contents of several additive components was presented. The experimental low-temperature heat capacity was measured in the temperature range of 1.85 to 302.8 K using a Quantum Design Physical Property Measurement System (PPMS) and the higher temperature Cp from 223.15 K to 382.15 K by Differential Scanning Calorimetry (DSC) method. For an interpretation of the experimental, low-temperature data, the vibrational heat capacity of the pure silver carp collagen was calculated based on the contribution of a sum of the vibrational heat capacity of 4248 amino acids. The vibrational heat capacity for each amino acids was taken from Advanced Thermal Analysis System (ATHAS) Data Bank for individual poly (amino acid) residues based on their group and skeletal vibrational spectra. Comparing of the experimental heat capacity of the collagen with additive components and the calculated vibrational heat capacity of the pure silver carp collagen shows that the differences range from around 10% at 100 K to 14% at 300 K temperature. Such thermal analysis can provide information about the contribution to Cp of unknown components or impurities in the investigated system.


Subject(s)
Carps , Collagen/chemistry , Fish Proteins/chemistry , Hot Temperature , Algorithms , Amino Acids , Animals , Calorimetry, Differential Scanning , Chemical Phenomena , Models, Theoretical , Polymers/chemistry , Thermodynamics
12.
Bioinformatics ; 36(9): 2778-2786, 2020 05 01.
Article in English | MEDLINE | ID: mdl-31971583

ABSTRACT

MOTIVATION: New single-cell technologies continue to fuel the explosive growth in the scale of heterogeneous single-cell data. However, existing computational methods are inadequately scalable to large datasets and therefore cannot uncover the complex cellular heterogeneity. RESULTS: We introduce a highly scalable graph-based clustering algorithm PARC-Phenotyping by Accelerated Refined Community-partitioning-for large-scale, high-dimensional single-cell data (>1 million cells). Using large single-cell flow and mass cytometry, RNA-seq and imaging-based biophysical data, we demonstrate that PARC consistently outperforms state-of-the-art clustering algorithms without subsampling of cells, including Phenograph, FlowSOM and Flock, in terms of both speed and ability to robustly detect rare cell populations. For example, PARC can cluster a single-cell dataset of 1.1 million cells within 13 min, compared with >2 h for the next fastest graph-clustering algorithm. Our work presents a scalable algorithm to cope with increasingly large-scale single-cell analysis. AVAILABILITY AND IMPLEMENTATION: https://github.com/ShobiStassen/PARC. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Subject(s)
Algorithms , Single-Cell Analysis , Cluster Analysis , RNA-Seq , Software , Exome Sequencing
13.
Transbound Emerg Dis ; 67(4): 1532-1542, 2020 Jul.
Article in English | MEDLINE | ID: mdl-31961008

ABSTRACT

This study investigated the potential of pooled milk as an alternative sample type for foot-and-mouth disease (FMD) surveillance. Real-time RT-PCR (rRT-PCR) results of pooled milk samples collected weekly from five pooling facilities in Nakuru County, Kenya, were compared with half-month reports of household-level incidence of FMD. These periodic cross-sectional surveys of smallholder farmers were powered to detect a threshold household-level FMD incidence of 2.5% and collected information on trends in milk production and sales. FMD virus (FMDV) RNA was detected in 9/219 milk samples, and using a type-specific rRT-PCR, serotype SAT 1 was identified in 3/9 of these positive samples, concurrent with confirmed outbreaks in the study area. Four milk samples were FMDV RNA-positive during the half-months when at least one farmer reported FMD; that is, the household-level clinical incidence was above a threshold of 2.5%. Additionally, some milk samples were FMDV RNA-positive when there were no reports of FMD by farmers. These results indicate that the pooled milk surveillance system can detect FMD household-level incidence at a 2.5% threshold when up to 26% of farmers contributed milk to pooling facilities, but perhaps even at lower levels of infection (i.e., below 2.5%), or when conventional disease reporting systems fail. Further studies are required to establish a more precise correlation with estimates of household-level clinical incidence, to fully evaluate the reliability of this approach. However, this pilot study highlights the potential use of this non-invasive, routinely collected, cost-effective surveillance tool, to address some of the existing limitations of traditional surveillance methods.


Subject(s)
Cattle Diseases/epidemiology , Disease Outbreaks/veterinary , Foot-and-Mouth Disease Virus/isolation & purification , Foot-and-Mouth Disease/epidemiology , Milk/virology , Animals , Cattle , Cattle Diseases/virology , Cross-Sectional Studies , Epidemiological Monitoring/veterinary , Farmers , Foot-and-Mouth Disease/virology , Foot-and-Mouth Disease Virus/genetics , Incidence , Kenya/epidemiology , Pilot Projects , Real-Time Polymerase Chain Reaction/veterinary , Reproducibility of Results , Serogroup
14.
Light Sci Appl ; 9: 8, 2020.
Article in English | MEDLINE | ID: mdl-31993126

ABSTRACT

Parallelized fluorescence imaging has been a long-standing pursuit that can address the unmet need for a comprehensive three-dimensional (3D) visualization of dynamical biological processes with minimal photodamage. However, the available approaches are limited to incomplete parallelization in only two dimensions or sparse sampling in three dimensions. We hereby develop a novel fluorescence imaging approach, called coded light-sheet array microscopy (CLAM), which allows complete parallelized 3D imaging without mechanical scanning. Harnessing the concept of an "infinity mirror", CLAM generates a light-sheet array with controllable sheet density and degree of coherence. Thus, CLAM circumvents the common complications of multiple coherent light-sheet generation in terms of dedicated wavefront engineering and mechanical dithering/scanning. Moreover, the encoding of multiplexed optical sections in CLAM allows the synchronous capture of all sectioned images within the imaged volume. We demonstrate the utility of CLAM in different imaging scenarios, including a light-scattering medium, an optically cleared tissue, and microparticles in fluidic flow. CLAM can maximize the signal-to-noise ratio and the spatial duty cycle, and also provides a further reduction in photobleaching compared to the major scanning-based 3D imaging systems. The flexible implementation of CLAM regarding both hardware and software ensures compatibility with any light-sheet imaging modality and could thus be instrumental in a multitude of areas in biological research.

15.
J Dairy Sci ; 102(4): 3569-3583, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30738665

ABSTRACT

Lipopolysaccharide (LPS) administration causes immunoactivation, which negatively affects production and fertility, but experimental exposure via an acute bolus is unlikely to resemble natural infections. Thus, the objectives were to characterize effects of chronic endotoxemia on production parameters and follicular development in estrous-synchronized lactating cows. Eleven Holstein cows (169 ± 20 d in milk; 681 ± 16 kg of body weight) were acclimated to their environmental surroundings for 3 d and then enrolled in 2 experimental periods (P). During P1 (3 d) cows consumed feed ad libitum and baseline samples were obtained. During P2 (7 d), cows were assigned to continuous infusion of either (1) saline-infused and pair-fed (CON-PF; 40 mL/h of saline i.v.; n = 5) or (2) LPS infused and ad libitum fed (LPS-AL; Escherichia coli O55:B5; 0.017, 0.020, 0.026, 0.036, 0.055, 0.088, and 0.148 µg/kg of body weight/h i.v. on d 1 to 7, respectively; n = 6). Controls were pair-fed to the LPS-AL group to eliminate confounding effects of dissimilar nutrient intake. Infusing LPS temporally caused mild hyperthermia on d 1 to 3 (+0.49°C) relative to baseline. Dry matter intake of LPS-AL cows decreased (28%) on d 1 of P2, then progressively returned to baseline. Relative to baseline, milk yield from LPS-AL cows was decreased on d 1 of P2 (12%). No treatment differences were observed in milk yield during P2. Follicular growth, dominant follicle size, serum progesterone (P4), and follicular P4 and 17ß-estradiol concentrations were similar between treatments. Serum 17ß-estradiol tended to increase (115%) and serum amyloid A and LPS-binding protein were increased (118 and 40%, respectively) in LPS-AL relative to CON-PF cows. Compared with CON-PF, neutrophils in LPS-AL cows were initially increased (45%), then gradually decreased. In contrast, monocytes were initially decreased (40%) and progressively increased with time in the LPS-AL cows. Hepatic mRNA abundance of cytochrome P450 family 2 subfamily C (CYP2C) or CYP3A was not affected by LPS, nor was there a treatment effect on toll-like receptor 4 or LBP; however, acyloxyacyl hydrolase and RELA subunit of nuclear factor kappa B tended to be increased in LPS-AL cows. These data suggest lactating dairy cows become tolerant to chronic and exponentially increasing LPS infusion in terms of production and reproductive parameters.


Subject(s)
Cattle , Endotoxemia/veterinary , Lipopolysaccharides/pharmacology , Ovarian Follicle/drug effects , Reproductive Health , Animals , Diet/veterinary , Endotoxemia/physiopathology , Estradiol/blood , Estrus , Female , Fertility , Lactation , Liver/metabolism , Milk , Ovarian Follicle/metabolism
16.
J Dairy Sci ; 102(4): 3584-3597, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30660419

ABSTRACT

Experimental objectives of this study were to characterize the systemic and intracellular metabolic response to continuous lipopolysaccharide (LPS) infusion in mid-lactation Holstein cows (169 ± 20 d in milk; 681 ± 16 kg of body weight). Following 3 d of acclimation, cows were enrolled in 2 experimental periods (P). During P1 (3 d), cows were fed ad libitum and baseline data were collected. In P2 (8 d), cows were assigned to 1 of 2 treatments: (1) saline-infused and pair-fed (CON-PF; i.v. sterile saline at 40 mL/h; n = 5) or (2) LPS-infused and fed ad libitum (LPS-AL; Escherichia coli O55:B5 at 0.017, 0.020, 0.026, 0.036, 0.055, 0.088, 0.148, and 0.148 µg/kg of body weight per hour for d 1 through 8, respectively; n = 6). During P2, CON-PF cows were pair-fed to LPS-AL cows to eliminate confounding effects of dissimilar nutrient intake. Blood samples were collected on d 1 and 2 of P1 and d 1, 3, 5, and 7 of P2. Following the P2 d 7 a.m. milking, adipose tissue, skeletal muscle, and liver biopsies were collected for reverse transcription quantitative PCR and Western blot analysis. To assess whole-body nutrient trafficking, an i.v. glucose tolerance test (GTT) was performed following the a.m. milking on P2 d 8; 4 h after the GTT, cows received an epinephrine challenge. During P2, there were no treatment differences in circulating glucose. Relative to P1, CON-PF cows had or tended to have decreased plasma ß-hydroxybutyrate and insulin (29 and 47%, respectively) during P2, whereas neither variable changed in LPS-AL cows, leading to an overall increase in ß-hydroxybutyrate and insulin (41 and 140%, respectively) relative to CON-PF cows. Circulating nonesterified fatty acids were increased from d 1 to 3 and subsequently decreased from d 3 to 7 in cows from both treatments. Blood urea nitrogen gradually decreased in CON-PF cows and increased in LPS-AL cows from d 1 to 5 of P2, resulting in an overall 25% increase in LPS-AL versus CON-PF cows. In response to the GTT, the glucose and insulin area under the curve were increased 33 and 56%, respectively, in LPS-AL compared with CON-PF cows; changes reflective of whole-body insulin resistance. However, protein abundance of insulin signaling markers within muscle, liver, and adipose tissue were similar between treatments. There were no observable treatment differences in the glucose or nonesterified fatty acids response to the epinephrine challenge. No treatment differences were observed in hepatic mRNA abundance of key gluconeogenic or lipid export enzymes. In conclusion, chronic LPS exposure altered multiple parameters of basal and stimulated metabolism, but did not appear to affect the molecular machinery evaluated herein.


Subject(s)
Cattle/metabolism , Lactation , Lipopolysaccharides/pharmacology , 3-Hydroxybutyric Acid/blood , Animals , Blood Glucose/metabolism , Body Weight , Cattle/blood , Diet , Fatty Acids, Nonesterified/blood , Female , Gluconeogenesis , Glucose Tolerance Test/veterinary , Insulin/blood , Insulin Resistance , Liver , Milk
17.
Cytometry B Clin Cytom ; 94(6): 935-940, 2018 11.
Article in English | MEDLINE | ID: mdl-30350400

ABSTRACT

BACKGROUND: Bone marrow (BM) aspirate analysis by flow cytometry (FC) is a key hematopathologic technique but dry taps hinder diagnosis. We describe the utility and limitations of a method of mechanically disaggregating BM trephine biopsies for FC. METHOD: Trephine biopsies mechanically disaggregated for FC between 2010 and 2016 were reviewed. We recorded cell yield, pathological findings, and turnaround time. Where available, results of trephine FC were compared with aspirate FC. RESULTS: Eighty BM trephine samples were processed, representing 4.3% of BM biopsies. Mechanical disaggregation yielded cellular samples in 98% of cases (median yield 3 × 106 nucleated cells). The most frequent diagnoses were B cell lymphoproliferative disorders (n = 26) and acute leukemia (n = 18). Trephine FC correlated with histochemistry findings in 94% of cases, but two Hodgkin lymphoma infiltrates were missed by FC, and trephine FC underestimated B cell infiltrate burden compared to immunohistochemistry (IHC). Fluorescence intensity of CD34 and CD45 on disease populations was similar in processed trephine and contemporaneous aspirate samples. Trephine FC results were available 2 days earlier than stained IHC slides. CONCLUSION: Mechanical disaggregation of BM trephine samples provided a cellular suspension suitable for diagnostic FC in most cases. Limitations were similar to aspirate FC: disease burden was underestimated and some infiltrates were missed. Trephine FC results were available earlier than trephine IHC. We conclude that trephine FC is a useful technique to complement trephine IHC in the event of a failed aspirate, providing rapid diagnostic immunophenotyping. © 2018 International Clinical Cytometry Society.


Subject(s)
Biopsy , Bone Marrow/pathology , Flow Cytometry , Adolescent , Adult , Aged , Aged, 80 and over , Bone Marrow/immunology , Bone Marrow Examination , Female , Humans , Immunohistochemistry , Immunophenotyping , Male , Middle Aged , Retrospective Studies , Young Adult
18.
J Dairy Sci ; 101(6): 5515-5530, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29550130

ABSTRACT

Activated immune cells are insulin sensitive and utilize copious amounts of glucose. Because chromium (Cr) increases insulin sensitivity and may be immunomodulatory, our objective was to evaluate the effect of supplemental Cr (KemTrace Cr propionate, 20 g/d; Kemin Industries Inc., Des Moines, IA) on immune system glucose utilization and immune system dynamics following an intravenous endotoxin challenge in lactating Holstein cows. Twenty cows (320 ± 18 d in milk) were randomly assigned to 1 of 4 treatments: (1) pair-fed (PF) control (PF-CON; 5 mL of saline; n = 5), (2) PF and Cr supplemented (PF-Cr; 5 mL of saline; n = 5), (3) lipopolysaccharide (LPS)-euglycemic clamp and control supplemented (LPS-CON; 0.375 µg/kg of body weight LPS; n = 5), and (4) LPS-euglycemic clamp and Cr supplemented (LPS-Cr; 0.375 µg/kg of body weight LPS; n = 5). The experiment was conducted serially in 3 periods (P). During P1 (3 d), cows received their respective dietary treatments and baseline values were obtained. At the initiation of P2 (2 d), either a 12-h LPS-euglycemic clamp was conducted or cows were PF to their respective dietary counterparts. During P3 (3 d), cows consumed feed ad libitum and continued to receive their respective dietary treatment. During P2, LPS administration decreased dry matter intake (DMI; 40%) similarly among diets, and by experimental design the pattern and magnitude of reduced DMI were similar in the PF cohorts. During P3, LPS-Cr cows tended to have decreased DMI (6%) relative to LPS-CON cows. Relative to controls, milk yield from LPS-challenged cows decreased (58%) during P2 and LPS-Cr cows produced less (16%) milk than LPS-CON cows. During P3, milk yield progressively increased similarly in LPS-administered cows, but overall milk yield remained decreased (24%) compared with PF controls. There were no dietary treatment differences in milk yield during P3. Circulating insulin increased 9- and 15-fold in LPS-administered cows at 6 and 12 h postbolus, respectively, compared with PF controls. Compared with LPS-CON cows, circulating insulin in LPS-Cr cows was decreased (48%) at 6 h postbolus. Relative to PF cows, circulating LPS binding protein and serum amyloid A from LPS-administered cows increased 2- and 5-fold, respectively. Compared with PF cows, blood neutrophil counts in LPS-infused cows initially decreased, then gradually increased 163%. Between 18 and 48 h postbolus, the number of neutrophils was increased (12%) in LPS-Cr versus LPS-CON cows. The 12-h total glucose deficit was 220 and 1,777 g for the PF and LPS treatments, respectively, but glucose utilization following immune activation was not influenced by Cr. In summary, supplemental Cr reduced the insulin response and increased circulating neutrophils following an LPS challenge but did not appear to alter the immune system's glucose requirement following acute and intense activation.


Subject(s)
Blood Glucose/metabolism , Cattle/immunology , Chromium/pharmacology , Lactation , Leukocytes/immunology , Animal Feed , Animals , Diet , Energy Metabolism/drug effects , Energy Metabolism/physiology , Female , Milk
19.
Reproduction ; 155(4): R169-R181, 2018 04.
Article in English | MEDLINE | ID: mdl-29363567

ABSTRACT

Endotoxemia can be caused by obesity, environmental chemical exposure, abiotic stressors and bacterial infection. Circumstances that deleteriously impact intestinal barrier integrity can induce endotoxemia, and controlled experiments have identified negative impacts of lipopolysaccharide (LPS; an endotoxin mimetic) on folliculogenesis, puberty onset, estrus behavior, ovulation, meiotic competence, luteal function and ovarian steroidogenesis. In addition, neonatal LPS exposures have transgenerational female reproductive impacts, raising concern about early life contacts to this endogenous reproductive toxicant. Aims of this review are to identify physiological stressors causing endotoxemia, to highlight potential mechanism(s) by which LPS compromises female reproduction and identify knowledge gaps regarding how acute and/or metabolic endotoxemia influence(s) female reproduction.


Subject(s)
Endotoxemia/etiology , Endotoxins/adverse effects , Reproduction/drug effects , Animals , Female , Humans
20.
J Dairy Sci ; 100(5): 4113-4127, 2017 May.
Article in English | MEDLINE | ID: mdl-28342610

ABSTRACT

Study objectives were to evaluate the effects of intentionally reduced intestinal barrier function on productivity, metabolism, and inflammatory indices in otherwise healthy dairy cows. Fourteen lactating Holstein cows (parity 2.6 ± 0.3; 117 ± 18 d in milk) were enrolled in 2 experimental periods. Period 1 (5 d) served as the baseline for period 2 (7 d), during which cows received 1 of 2 i.v. treatments twice per day: sterile saline or a gamma-secretase inhibitor (GSI; 1.5 mg/kg of body weight). Gamma-secretase inhibitors reduce intestinal barrier function by inhibiting crypt cell differentiation into absorptive enterocytes. During period 2, control cows receiving sterile saline were pair-fed (PF) to the GSI-treated cows, and all cows were killed at the end of period 2. Administering GSI increased goblet cell area 218, 70, and 28% in jejunum, ileum, and colon, respectively. In the jejunum, GSI-treated cows had increased crypt depth and reduced villus height, villus height-to-crypt depth ratio, cell proliferation, and mucosal surface area. Plasma lipopolysaccharide binding protein increased with time, and tended to be increased 42% in GSI-treated cows relative to PF controls on d 5 to 7. Circulating haptoglobin and serum amyloid A concentrations increased (585- and 4.4-fold, respectively) similarly in both treatments. Administering GSI progressively reduced dry matter intake (66%) and, by design, the pattern and magnitude of decreased nutrient intake was similar in PF controls. A similar progressive decrease (42%) in milk yield occurred in both treatments, but we observed no treatment effects on milk components. Cows treated with GSI tended to have increased plasma insulin (68%) and decreased circulating nonesterified fatty acids (29%) compared with PF cows. For both treatments, plasma glucose decreased with time while ß-hydroxybutyrate progressively increased. Liver triglycerides increased 221% from period 1 to sacrifice in both treatments. No differences were detected in liver weight, liver moisture, or body weight change. Intentionally compromising intestinal barrier function caused inflammation, altered metabolism, and markedly reduced feed intake and milk yield. Further, we demonstrated that progressive feed reduction appeared to cause leaky gut and inflammation.


Subject(s)
Gastrointestinal Tract/microbiology , Lactation , 3-Hydroxybutyric Acid/blood , Animal Feed , Animals , Cattle , Diet/veterinary , Fatty Acids, Nonesterified/blood , Female , Inflammation/metabolism , Milk/metabolism
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