bluuebunny/crossref_metadata_2025 huggingface dataset:
Clinical Rickets in Rural Kenyan Preschoolers
Authors: Neumann Charlotte Grantz , Bwibo Nimrod O
Published: June 2021

Clinical rickets is reemerging in industrialized and developing countries. Clinical rickets among preschoolers, associated risk factors, intervention, and outcomes in a rural Kenyan study is reported. Baseline evaluation of 1–4 year‐old preschool children (n=324) prior to a nutrition intervention study was conducted. Usual food intake was assessed by 24‐hr recall. Anthropometric measures were obtained. Health history and physical examinations, including signs of nutritional deficiency, were conducted. No biochemical analyses for vitamin D and calcium were performed. Of the 324 children examined, 28 (6.6%), including 3 sets of twins, were diagnosed with clinical rickets. Developmental delays of sitting, walking, and teething were found. Bone deformities such as frontal and parietal bossing of the skull, chest deformities and rachitic rosaries, widening of wrists and ankles, and bowing of the extremities were observed. Risk factors were weaning under 1y, use of cereal‐based, unfortified foods, negligible cow or goat milk consumption, and being kept indoors when mothers were working in the fields. Treatment included of whole milk daily, 500mg of vitamin D‐3 tablets daily, advice to mothers about daily exposure of children to sunshine and inclusion of milk and other animal foods in the daily diet. Most features of rickets disappeared after 3–6 months. Deficient intake of calcium, limited to exposure to sunshine (Vitamin D), and poor quality weaning diets appear to be major factors. USAID Global Livestock CRSP DAN‐1328‐G‐00‐0046‐00
Vitamin A supplementation modifies associations between intestinal immune responses and enteric pathogen infections among Mexican children.
Authors: Long Kurt Zane , Santos Jose I , Rosado Jorge L , Mamun Abdullah , Nanthakumar Nanda
Published: June 2021

The effect of vitamin A supplementation on childhood infectious disease outcomes may result from the regulatory effect it has on the pathogen‐specific immune response. The associations between intestinal cytokine responses and diarrheal pathogen infection durations were compared between children receiving vitamin A or a placebo in a randomized clinical trial carried out in Mexico City. Parametric hazards models incorporating categorized variables for TNF‐α, IFN‐γ and IL‐4 were fit to overall durations of enteropathogenic E. coli (EPEC), enterotoxigenic E. coli (ETEC), and G. lamblia infections and durations stratified by treatment arm. Overall, increased TNF‐α levels were associated with increased EPEC infection durations (HR 0.28 95% CI 0.09–0.84); increased IFN‐γ levels were associated with reduced EPEC durations and increased G. lamblia durations (HR 3.21 95% CI 1.24–8.29 and HR 0.12 95% CI 0.03–0.44, respectively); and increased IL‐4 levels were associated with increased EPEC durations but reduced ETEC durations (HR 0.01 95% CI 0.00–0.10 and 2.67 95% CI 1.08–6.60, respectively). Vitamin A eliminated the association between increased TNF‐α levels and increased EPEC durations and the association between increased IFN‐γ/IL‐4 levels and increased ETEC and G. lamblia durations. Vitamin A reduces the negative effects that TNF‐α and IFN‐γ have on the resolution of non‐invasive enteric infections.
POST‐TRANSLATIONAL REGULATION OF LXRβ: THE ROLE OF LIGAND IN ENHANCING PROTEIN STABILITY
Authors: Clarke Stephen L. , Repa Joyce J.
Published: June 2021

LXRs are ligand‐activated transcription factors that bind oxysterols to regulate the expression of genes involved in cholesterol homeostasis. In mouse models of athersclerosis, administration of synthetic LXR agonists reduces atherosclerotic lesions, but also increases hepatic fatty acid synthesis. This undesirable side‐effect is attributable to LXRα, thus the identification of LXRβ‐selective agonists is crucial to improving the therapeutic potential of synthetic agonists. Our goal is to identify novel regulatory mechanisms responsible for modulating LXR activity. We have created inducible cell lines expressing epitope‐tagged LXRα and LXRβ. Cells expressing LXRα and LXRβ exhibited a 10‐ and 2‐fold activation, respectively, of an idealized reporter, indicating that these proteins were functional. Interestingly, treatment with either the synthetic LXR ligand T1317 or 24(S),25‐epoxycholesterol increased LXRβ protein abundance, whereas LXRα was unchanged. Treatment with a RXR agonist did not alter the abundance of either protein, suggesting enhanced stability is not dependent on transactivation of the RXR/LXR heterodimer. In summary, we have identified a ligand‐dependent mechanism through which LXRβ protein stability is regulated, which will further our understanding of these sterol sensors in regulating reverse‐cholesterol transport and decreasing the risk of cardiovascular disease.
A Phase I/II Dose‐Escalation Trial of Vitamin D3 with Calcium Supplementation in Patients with Multiple Sclerosis
Authors: Kimball Samantha M , Burton Jodie , Vieth Reinhold , O'Connor Paul
Published: June 2021

There is evidence to suggest that vitamin D nutritional status may influence the development and progression of multiple sclerosis (MS). To characterize the safety profile of high‐dose oral vitamin D3 in MS, we conducted a phase I/II dose‐escalation trial of vitamin D3 with calcium supplementation in patients with MS.

In 52‐week trial patients with MS were matched (age, gender, disease duration, Expanded Disability Status Scale, disease modifying therapy, and MS subtype), stratified, and randomized to treatment or control. The treatment group received escalating doses of vitamin D3 (4,000â 40,000 IU/d) and calcium (1200mg/d). The primary endpoint was change in serum calcium concentrations in the treatment group. Baseline and end‐of‐trial measures of disease progression will be compared. Immune system biomarkers will be compared between baseline and end‐of‐study within the treatment group and between treatment and control subjects. Interim analysis: 9/25 treatment patients remain in‐study while 15/25 have finished. Serum and urine calcium levels have remained within normal ranges (2.2â 2.6mmol/L) for all participants with no incidence of hypercalcemia or hypercalciura. There was no significant difference between control and treatment groups. Mean serum 25(OH)D concentrations have increased significantly from 73.5 to 402.1 nmol/L (p<0.001) at the highest dose (n=14). Further results to follow.
Gamma Delta T Cell Dependent Inflammation and Wound Healing in the Mouse Corneal Epithelium
Authors: Byeseda Sarah Elizabeth , Tawil Ahmad , Li Zhijie , Burns Alan , Smith C. Wayne
Published: June 2021

We found that γδ T cells migrate into murine corneal epithelium in response to epithelial wounding, and wound healing and inflammation are significantly reduced in TCRδ −/− mice (Am. J. Pathol 171:838–845, 2007). The current work is to define mechanisms for migration of γδ T cells into corneal epithelium. Limbal and paralimbal corneal epithelium was collected at 0 and 3 hrs after central abrasion in female C57BL/6 mice for qrtPCR, and immunocytology. Results: ICAM‐1 mRNA was increased 26 fold at 3 hrs. Anti‐ICAM‐1 staining was negative at 0 hr, but strongly positive over the limbal and paralimbal epithelium at 3 hrs. γ/δ T cells increased at 3 hrs after injury, but ICAM‐1−/− mice failed to show an increase. Of 11 chemokine receptors probed, only CCR3 and CCR5 were significantly increased in wildtype mice at 3 hrs. mRNA for chemokines recognized by these receptors was significantly increased: CCL3 (MIP‐1α), CCL4 (MIP‐1β), CCL5 (RANTES) and CCL7 (MCP‐3). Further, CXCL10 (IP‐10) mRNA was also significantly increased. CXCL10 is known to attract some γδ T cells, but its receptor (CXCR3) was not evident here. Conclusion: The migration of γδ T cells into murine corneal epithelium in response to epithelial abrasion appears to depend on ICAM‐1 expression, and since CCR5 is reported on some γδ T cells, our observations suggest a mechanism for attraction into corneal epithelium.

Source of research support: General Clinical Research Centers
Oxidative damage to human cortex in aging an antioxidant use
Authors: Sonnen Joshua Aaron , Gray Shelly , Larson Eric B. , Montine Thomas Jude
Published: June 2021

Oxidative damage has been proposed as an underlying mechanism of the neurodegenerative processes in age‐related cognitive decline and dementia. Frozen parietal cortex from rapid autopsies from the Adult Changes in Thought study, a longitudinal, community‐based study of aging with extensive medication and clinical history and neuropathologic endpoints, was evaluated for absolute content of oxidative products of arachadonic acid (IsoP), docosahexaenoic acid (NeuroP) and adrenic acid (MyeloP) as surrogates for oxidative damage to plasma membranes, neuron cell membranes and myelin membranes respectively. Current smoking, but not obesity were associated with increased IsoP and NeuroP, but not MyeloP levels, and history of Vit C and E use failed to moderate this effect.
Neurodegenerative Phenotypes Induced by MYC‐Driven Neuronal Cell Cycle Re‐entry: Relevance to Alzheimer Disease
Authors: Smith Mark A. , Casadesus Gemma , Richardson Sandy L. , Perry George , Petersen Robert B. , Lee Hyoung‐gon
Published: June 2021

Aberrant cell cycle activation in neurons has emerged as a potential pathogenic mechanism of neuronal dysfunction/death in many neurodegenerative diseases such as Alzheimer disease (AD). However, the exact role of cell cycle re‐entry in disease pathogenesis is unclear, primarily because of the absence of research models to study the effects of cell cycle re‐entry in mature neurons in vivo. To address this issue, we recently developed a new transgenic mouse model which can be induced to specifically re‐drive forebrain neurons into the cell cycle (CaMKII‐MYC). Analysis of these animals shows that driving neurons into the cell cycle leads to many phenotypic changes characteristic of AD including: 1) ectopic expression of cell cycle proteins; 2) hyperphosphorylation of tau; 3) accumulation of intraneuronal amyloid‐beta; 4) a “neurodegenerative” (TUNEL) phenotype; 5) astrogliois; and 6) major cognitive deficits (Y‐maze and Morris Water Maze). Our findings provide compelling evidence that dysregulation of cell cycle re‐entry plays a causative role in neurodegeneration in vivo.
A clinicopathological correlation study of cognitive status and senile plaques and neurofibrillary tangles in clinically well‐characterized individuals of extreme old age
Authors: Purohit Dushyant , Batheja Nirmala , Haroutunian Vahram , Sano Mary , Grossman Hillel , Perl Daniel
Published: June 2021

We describe the distribution of senile plaques (SP) and neurofibrillary tangles (NFT) in a series of 34 brain specimens derived from 90+ year‐old individuals (see table below) who had been systematically evaluated for cognitive function with the final assessments expressed using the Clinical Dementia Rating score (CDR; mean 2.62, SD ±1.27, range 0–5). We determined the extent of SP as a mean density of 5 neocortical areas and of NFT using aggregate density assessments in neocortex, hippocampus and entorhinal cortex. Due to the relatively small sample, we grouped the cases into normal to mild/moderate dementia and severe dementia as follows, and used the Wilcoxon Two‐Sample Test to compare the two groups.

Although our sample size is relatively small, there was a statistically significant positive correlation between the extent of dementia (in CDR scores) and SP density score (one sided p=0.011), but not for the NFT density score (one sided p=0.076). This study is ongoing with the hope providing further insights on correlates for both normal cognitive function and dementia in additional prospectively evaluated subjects of extreme old age.

Supported by NIH grants PO1 AG‐02219 and P50 AG‐05138
MGMT Promoter Methylation Status Predicts Survival in Pediatric Glioblastoma
Authors: Zhang Wenyong William , Mehta Vidya , Courteau Girard R , Su Jack , Lau Ching , Webb Renee , Adesina Adekunle M
Published: June 2021

Pediatric glioblastoma (pGBM) represents 15% of pediatric brain tumors with a 3‐year survival rate of < 20%. Effective DNA repair is an important cellular mechanism for resistance to chemotherapy and radiation. The role of this mechanism in pGBM remains poorly understood. We evaluated the expression pattern of proteins (by immunohistochemistry) involved in the repair of DNA damage induced by alkylating agents, as well as, mismatch and base excision repairs including hMLH1, hMSH2 and PARP in fifteen pGBMs. MGMT promoter methylation was analyzed using methylation specific PCR and pyrosequencing. The relationship between DNA repair pathway alteration and survival was analyzed.

MGMT promoter methylation was detected in 33% of tumors. Loss of hMLH1 and hMSH2 protein expression was seen in 47% and 53% of tumors, respectively. PARP expression was seen in 100% of pGBMs. hMLH1, hMSH2 and PARP expressions did not correlate with either event free survival or overall survival (p > 0.05). MGMT promoter methylation correlated significantly with better overall survival (p = 0.035). We conclude that MGMT promoter methylation status is a predictor of better survival in treated pGBM.
Adding to the controversy: Continuously‐infused human C‐reactive protein reduces atherosclerosis in apolipoprotein E‐deficient mice
Authors: Ortiz Miguel A , Sosa Marcelo J , Walker Candace L , Woods John R , Campana Gonzalo L , Labarrere Carlos A
Published: June 2021

The role of C‐reactive protein (CRP) in atherosclerosis mouse models remains controversial, with studies showing both proatherogenic and no effects. We hypothesized that the discrepancies might relate to the use of azide‐ or endotoxin‐contaminated native (n) CRP, its episodic administration, to the use of CRP transgenic vs. non‐transgenic mice, or to biased sampling of the aorta in evaluating atherosclerotic lesions. We administered azide‐ and endotoxin‐free human nCRP (n=11) or placebo (n=11) to 12‐week‐old apolipoprotein E‐deficient (apoE−/−) male mice as a continuous infusion for 4 weeks (20.4 μg/day). Animals treated with nCRP developed fewer lesions (7.24 ± 1.59%) in the whole aorta than controls (9.90 ± 2.11%) (p= 0.0026; R2 = 0.3578). When aortic regions were analyzed separately, the extent of atherosclerotic lesions showed significant differences for nCRP‐treated vs. controls in the thoraco‐abdominal region (3.14 ± 1.27% vs. 4.67 ± 1.89%) (p = 0.0322; R2 =0.2004); but the differences were not significant in the aortic arch (3.71 ±1.15% vs. 4.63 ± 1.16%) (p = 0.0715; R2 = 0.1465), the iliac region (0.40 % ± 0.35 vs. 0.62; ± 0.30%) (p = 0.1247; R2 = 0.1086), or the aortic root (65.02 ± 7.81% vs. 64.71± 9.65%) (p= 0.9393; R2 = 0.0004). These comparisons show an unexpected reduction of atherosclerosis in nCRP‐treated mice. They also emphasize the methodological importance of examining the whole aorta, rather than arbitrarily selected regions, to gain a valid understanding of atherosclerosis in this model.
DNA Replication and Latency in Herpes Simplex Viruses
Authors: Lehman I. Robert
Published: June 2021

The 152‐kbp herpes simplex virus type 1 (HSV‐1) genome encodes 75 genes of which seven are indispensable for DNA replication. During lytic infection, the HSV‐1 genome circularizes and replication proceeds in two phases: The first is a theta type mechanism initiated at one of the three origins. The product of one of the essential seven genes, the UL 9 protein, serves as the replication initiator, which binds to and unwinds DNA at a viral origin. The Theta phase is followed by rolling circle replication, the predominant mode of HSV‐1 replication. The rolling circle phase has been reconstituted with the six remaining essential gene products which include a DNA polymerase with its associated processivity factor, a single stranded DNA binding protein and a heterotrimeric helicase – primase. The UL 9 protein is the limiting component in DNA replication and is the site at which HSV‐1 DNA replication is regulated.

After replication in infected epithelial cells of the skin or bucal mucosa, HSV‐1 gains entrance to sensory nerve termini and establishes a latent infection. The mechanism that leads to the establishment of latency is not understood. We have found that the phosphorylated form of the UL9 protein interacts with the human neural F‐box‐42kDa protein (NFB 42) a neuron specific component of the E3 ubiquitin ligase complex. It is polyubiquinated and then degraded via the 26 S proteosome pathway. NFB 42 is found primarily in the cytosol, whereas the UL 9 protein is located predominantly in the nucleus. We have identified an HSV‐1 dependent shuttling of NFB 42 between the cytosol and the nucleus which mediates the nuclear export of the UL 9 protein. These results suggest a mechanism by which the latency of HSV‐1 can be established in neuronal cells.

Supported by NIH Grant AI 26538
N‐Terminal and C‐terminal fragments of dentin matrix protein 1(DMP1) are distributed differently in bone, dentin and cells.
Authors: Maciejewska Izabela , Svoboda Kathy , Butler William , Qin Chunlin
Published: June 2021

DMP1 is critical for biomineralization. In the extracellular matrix of bone and dentin, DMP1 shows as N‐terminal and C‐terminal fragments derived from proteolitic cleavage. In vitro study showed that the C‐terminal fragment promotes mineralization. Information about the N‐terminal fragment function is lacking. Aim of this study was to examine if DMP1 N‐terminal and C‐terminal fragments were localized differently in bone or dentin. Rat bones and teeth were stained immunohistochemically with antibodies that specifically recognized DMP1 N‐terminal and C‐terminal fragments and subsequently assessed with a confocal microscope. Different distribution of both fragments was observed. In the growth plate of bone only N‐terminal fragment was present in a proliferation and hypertrophic zone, while the C‐terminal fragment occupied ossification zone. In tooth, predentin reacted stronger with anti‐N‐terminal fragment antibody, while dentin reacted stronger with the anti‐C‐terminal fragment antibody. Different localization of the N‐terminal and C‐terminal fragments suggests that they have diverse roles in biomineralization. We believe that the C‐terminal fragment promotes mineralization, while the N‐terminal fragment serves as an inhibitor. Supported by NIH grant DE005092 (CQ).
Development of an education track in anatomy PhD at Indiana University School of Medicine
Authors: Brokaw James Joseph
Published: June 2021

The last two decades have witnessed fundamental changes in the way graduate students are trained in anatomy departments. No longer are students routinely required to learn and teach the traditional anatomical subdisciplines to earn their PhDs. Paradoxically, a doctorate in anatomy no longer guarantees any expert knowledge of anatomy. As classically trained anatomists retire and leave the workforce, they are not being replaced by newly minted PhDs with the requisite training and career focus needed to maintain the teaching mission. In consequence, the nation's health professional schools are faced with a growing shortage of qualified anatomy instructors, especially in gross anatomy. To help address this problem, the Department of Anatomy and Cell Biology, in consultation with the School of Education, designed a separate PhD track for students who desire a career focus in education rather than biomedical research. The goal of the education track is twofold: (1) to provide students with extensive training in all of the anatomical subdisciplines coupled with sufficient teaching experience to be fully prepared to assume major educational responsibilities upon graduation and (2) to train students to conduct rigorous, hypothesis‐driven medical education research and other scholarly work necessary for promotion and tenure. The proposed five‐year training program will require formal coursework in anatomy (31 hours), education (18 hours), statistics (6 hours), and electives (9 hours), as well as 26 hours for an educational research project. Once approved, the education track will produce a small but stable supply of doctoral‐level anatomy educators for a growing academic market.
A Mitochondrial Paradigm for Metabolic and Degenerative Diseases, Aging, and Cancer
Authors: Wallace Douglas C.
Published: June 2021

The human cell is assembled from two different organisms: the nucleo‐cytosol organism which specializes in structure and whose genes are Mendelian and the mitochondrial organism which specializes in energy and whose genes are maternal and stochastic. Inherited pathogenic mitochondrial DNA (mtDNA) mutations have been linked to a wide range of metabolic and degenerative diseases and the introduction of mtDNA mutations into the mouse germline has demonstrated that mtDNA mutations are sufficient to cause age‐related diseases. Somatic mtDNA mutations accumulate with age in a broad spectrum of organisms and introduction of catalase into the mouse mitochondrial matrix reduces the mtDNA somatic mutation rate and extends life span. Increasing Drosophila cAMP levels also reduces mitochondrial reactive oxygen species (ROS) and extends life span, and treating short‐lived Drosophila mutants with mitochondrially‐targeted antioxidants can restore the life span. Ancient adaptive mtDNA polymorphisms have been associated with altered risk for metabolic and neurodegenerative diseases and somatic mtDNA mutations are elevated in the brains of patients with neurodegenerative disease. Finally, both germline and somatic mtDNA mutations are associated with various cancers. Therefore, diseases which appear “complex” when viewed exclusively from the nucleo‐cytosol perspective might be more readily understood if the contribution of the mitochondrial organism were also considered.
Lipids as ligands of nuclear receptor mediated gene expression
Authors: Repa Joyce J. , Clarke Stephen L. , McDonald Jeffrey G.
Published: June 2021

The liver X receptors (LXRalpha and LXRbeta) are members of the nuclear hormone receptor family of ligand‐activated transcription factors. LXRs have been identified as cellular sterol sensors that are activated by cholesterol‐derived oxysterols to increase the expression of genes that contribute to cholesterol catabolism, efflux and elimination. These qualities make the LXRs attractive therapeutic targets for intervention in atherosclerosis. The majority of studies defining the actions of LXRs have been performed in the mouse model, taking advantage of genetically modified mouse strains devoid of LXRs. When an LXRalpha‐null mouse is fed dietary cholesterol, it fails to increase the expression of LXR target genes and consequently accumulates plasma and hepatic cholesterol and shows no increase in plasma and liver triglycerides. Interestingly, the Golden Syrian hamster also shows this dietary cholesterol‐induced phenotype, and fails to exhibit upregulation of hepatic LXR target genes such as CYP7A1 and SREBP‐1c. These observations prompted us to ask if the LXR‐signaling pathway is intact in the hamster, and whether we could use these qualities to further investigate LXR biology using the cholesterol‐fed hamster.

We have cloned and characterized hamster LXRalpha, evaluated the promoter motifs of LXR target genes, and compared the effects of dietary cholesterol and synthetic LXR ligands on cholesterol homeostasis and hepatic gene regulation to define this differential response to dietary cholesterol in this valuable animal model.

Supported by a grant from the American Heart Association (JJR)
Structural models of inhibition in neurotransmitter sodium symporters
Authors: Singh Satinder Kaur , Gouaux J. Eric
Published: June 2021

Neurotransmitter sodium symporters (NSS) play a critical role in terminating synaptic transmission by utilizing preexisting ion gradients to catalyze the thermodynamically unfavorable movement of small molecules, including the biogenic amines, from the synapse to neuronal and glial cytoplasms. Their dysfunction has been implicated in many neuropsychiatric diseases, and they are the target of a broad array of therapeutic and addictive compounds. Steady‐state kinetic data have revealed the existence of both competitive and noncompetitive modes of inhibition. Despite these strides, atomic‐level insight into inhibitor action has remained elusive. To address this dearth of knowledge, we employed LeuT, a leucine transporter and prokaryotic NSS homologue, as a structural paradigm. Through a combination of steady‐state kinetics, radioligand binding, dissociation assays, and X‐ray crystallography, we have pinpointed an allosteric antagonist binding site in an extracellular‐facing vestibule located approximately 11 Å above the substrate binding site. More importantly, we have defined molecular principles that may be germane to noncompetitive inhibition in eukaryotic NSS members and permit the rational design of novel noncompetitive inhibitors with therapeutic potential.

Research was supported by NIH and HHMI.
Chromatin Assembly and Disassembly During Genomic Processes
Authors: Tyler Jessica K , Williams Stephanie , Chen Chin‐Chuan , Carson Joshua
Published: June 2021

Chromatin assembly and disassembly has long been acknowledged to accompany the process of DNA replication. Accordingly, we previously discovered a key histone chaperone involved in the assembly of chromatin during DNA replication, termed Asf1 (Tyler et al., Nature 1999). It appeared likely, but unproven, that chromatin would also need to be disassembled to enable DNA repair and transcription to occur, and then reassembled after these processes are complete. By continuing our analysis of the defects of yeast that lack specific histone chaperones, we have found that disassembly of chromatin from promoter regions is a broadly‐utilized mechanism for the regulation of Eukaryotic activation, while chromatin reassembly onto promoters is required for transcriptional repression (Adkins et al., Molecular Cell, 2004; Adkins and Tyler, Molecular Cell, 2006). We will present our most recent mechanistic insights into these chromatin dynamics. In addition, we will present data demonstrating that chromatin is also disassembled and reassembled during double‐strand DNA repair, and the influence of these chromatin dynamics on cell survival.
Under the hood of the replisome: A single‐molecule view of DNA replication
Authors: Van Oijen Antoine M
Published: June 2021

Advances in optical imaging and molecular manipulation techniques have made it possible to observe individual enzymes and record molecular movies that provide new insight into their dynamics and reaction mechanisms. In a biological context, most of these enzymes function in concert with other enzymes in multiprotein complexes, so an important future direction will be the utilization of single‐molecule techniques to unravel the orchestration of large macromolecular assemblies. I will discuss results of single‐molecule experiments on the replisome, the molecular machinery that is responsible for replication of DNA. We stretch individual DNA molecules and use their elastic properties to obtain dynamic information on the proteins that unwind the double helix and copy its genetic information. Furthermore, we use fluorescence microscopy to obtain detailed information about the spatial distribution of eukaryotic replication origins along DNA.
Growth and survival signaling by lipid kinases
Authors: Cantley Lewis C.
Published: June 2021

The phosphoinositide 3‐kinase (PI3K) pathway plays a critical role in cell growth regulation. PI3K generates the lipid, phosphatidylinositol‐3,4,5‐trisphosphate (PIP3), that acts as a membrane bound second messenger to activate AKT/PKB family protein Ser/Thr kinases as well Tec family protein‐Tyr kinases. PIP3 also regulates proteins that control Arf, Rac and Ras family GTP‐binding proteins. This lipid is elevated in cancers, either due to loss of PTEN, the phosphatases that degrades it, or due to constitutive PI3K activity because of activating mutations in PIK3CA or an upstream activator of PI3K. The ultimate consequence of activating PI3K is to generate changes in signaling networks and gene expression patterns that promote cell growth, cell survival and cell movement. In order to elucidate the role of the PI3K pathway in normal cell growth and in cancer, we have generated mice in which genes for PI3K are deleted or activated in specific tissues. In addition, we have investigated the biochemical mechanisms by which PI3K becomes activated in human cancers. Our progress in these areas will be summarized.
Prevalence of Oxidative Stress and Metabolic Syndrome in Adults with and without spinal cord injury
Authors: Nelson Mindy J Dopler , Burri Betty Jane , Neidlinger Terry R , Stanhope Kimber , Havel Peter J
Published: June 2021

Objectives: To investigate the extent of oxidative stress and metabolic syndrome (MetS) in people with spinal cord injuries (SCI) and to identify the major factors associated with oxidative stress and MetS in this population.

Methods: Twenty‐four subjects with paraplegia (PARA), 26 subjects with tetraplegia (TETRA), and 28 able‐bodied controls (CNTL) were recruited from Northern California. MetS was defined as having ≥ 3 of the following components: (a) BMI ≥ 30.0 kg/m2; (b) fasting plasma high‐density lipoprotein <40 mg/dL for males; <50 mg/dL for females; (c) fasting plasma triglyceride >150 mg/dL; (d) ≥ 130mmHg systolic (SBP) or ≥ 85mmHg diastolic blood pressure (DBP) (e) fasting plasma glucose 100–125 mg/dL, fasting plasma insulin ≥ 20uU /mL, or homeostasis model assessment of insulin resistance ≥ 4.0. Antioxidant activity was measured using vitamin E and TBARS.

Results: Subjects with SCI had greater incidence of MetS than CNTL (29.2% of PARA, 15.4% of TETRA, and 3.6% of CNTL.) MetS was not significantly correlated with vitamin E or TBARS. Location of spinal cord lesion correlated with SBP (r=0.522; p<0.0001) and DBP (r=0.319; p=0.026.) TBARS was 20.3% higher in PARA with lesions at L3‐L4 than in TETRA with C2‐C5 lesions (p=0.044.)

Conclusion: People with SCI are at greater risk for MetS than CNTL and location of spinal cord lesion may contribute to this risk.

Supported by Spinal Cord Injury Research Foundation Grant #1803, Paralyzed Veterans of America
Increased water intake reduces metabolic syndrome over 12 mo in overweight dieting women, independent of diet composition, activity and weight loss
Authors: Stookey Jodi , Gardner Christopher , Popkin Barry
Published: June 2021

Drinking water acutely influences glycemic control, lipid metabolism, and blood pressure. To determine if drinking water reduces risk of the metabolic syndrome over time, secondary analyses were conducted on data from the Stanford A TO Z weight loss intervention on 155 overweight women (25–50 y) who reported less than 1L/d drinking water at baseline. Diet, physical activity, anthropometry, blood chemistries, and blood pressure were assessed at baseline, 2, 6, and 12 mo. At each time point, mean daily intakes of drinking water, total energy, macronutrients (% of Energy) and food water content were estimated using three unannounced 24‐hr diet recalls. In mixed models, drinking 1L or more water per day was associated with significant decreases in fasting insulin, HOMA, triglycerides, total cholesterol, LDL, and blood pressure over 12 mo. Drinking 1L or more water per day was associated with significantly increased odds of recovering from the metabolic syndrome (NCEP ATPIII) over 12 mo (OR: 3.9, 95%CI: 1.7–8.8, p = 0.001). The associations were independent of age, baseline status, weight loss diet group, energy intake, diet composition, physical activity and weight change. The results suggest that drinking water may reduce risk of the metabolic syndrome.
Choline intakes at AI levels are sufficient in preventing liver dysfunction in Mexican American men but are not optimal in minimizing plasma total homocysteine increases after a methionine load
Authors: Caudill Marie A , Veenema Kristin , Solis Claudia , Wang Wei , Li Rui , Maletz Charles
Published: June 2021

This controlled feeding study investigated the influence of choline intake ranging from 300 to 2200mg/d on biomarkers of choline status. Mexican American men (n=60) differing in methylenetetrahydrofolate reductase (MTHFR) C677T genotype (29 677TT, 31 677CC) consumed a diet providing 300mg/d choline plus supplemental choline intakes of 0, 250, 800 or 1900 mg/d for total choline intakes of 300, 550 (choline AI), 1100 or 2200mg/d, respectively for 12‐wk; 400mcg/d as dietary folate equivalents and 173mg/d betaine were consumed throughout the study. Plasma choline and betaine increased (P<0.05) in response to 550, 1100 and 2200mg/d choline (2200>1100=550) whereas no change was observed on the 300mg/d group. Plasma phosphatidylcholine declined (P<0.05) in response to 300mg/d possibly due to declining folate status; no changes were observed in the other choline intake groups. After a methionine load, choline intakes of 1100 and 2200 mg/d groups attenuated (P<0.006) the rise in plasma tHcy relative to the 300 and 550 mg/d groups. No changes in plasma ALT or AST concentrations were detected regardless of choline intake. These data suggest that 550 mg/d choline is sufficient to prevent liver dysfunction in this population; higher intakes are needed to optimize other measured end‐points. Supported by NIH Grant #S06GM053933.
Regulation of Prostaglandin E2 (PGE2)‐induced IL‐6 production by Epigallocatechin‐3‐gallate (EGCG) in rheumatoid arthritis synovial fibroblasts
Authors: AHMED SALAHUDDIN , KWAN KEVIN , MAROTTE HUBERT , KOCH ALISA E.
Published: June 2021

Prostaglandin E2 (PGE2) induces joint inflammation and bone destruction in rheumatoid arthritis (RA), at least in part, by producing the bone destructive cytokine interleukin‐6 (IL‐6) via E‐prostanoid (EP) receptors. In the present study using RA synovial fibroblasts, we evaluated (a) the mechanism through which PGE2 induces IL‐6 production; and (b) the efficacy of green tea polyphenol epigallocatechin‐3‐gallate (EGCG) in suppressing PGE2‐induced IL‐6 production. The results showed that PGE2 induced time‐ and concentration‐dependent IL‐6 production in RA synovial fibroblasts, which was mimicked by a selective EP2 agonist, butaprost (p<0.05, n=4). Blockade of the EP4 receptor by a selective competitive antagonist GW627368X further enhanced PGE2 induced IL‐6 production, suggesting a possible compensatory mechanism. Pretreatment with EGCG (10 and 20 μM) significantly inhibited PGE2‐induced IL‐6 production in RA synovial fibroblasts (p<0.05, n=3). Evaluation of signaling pathways using specific inhibitors pointed to an important mediatory role of Janus protein tyrosine kinases (JAKs) and nuclear factor‐κB (NF‐κB) in PGE2‐ induced IL‐6 production. These in vitro findings suggest that EGCG inhibits PGE2‐induced IL‐6 production possibly via modulation of PGE2‐induced JAK/STAT and NF‐κB pathways. Thus, EGCG may be of potential therapeutic value in regulating bone destruction observed in RA.
Osteoporosis prevention using soy: the OPUS study
Authors: Wong William W. , Lewis Richard D. , Steinberg Francene M. , Murray Michael J. , Cramer Margaret A. , Amato Paula , Young Ronald L. , Barnes Stephen , Ellis Kenneth J. , Shypailo Roman J. , Fischer Joan , Fraley J. Kennard , Konzelmann Karen L. , Smith E. O’Brian
Published: June 2021

Soy isoflavones are believed to have anti‐osteoporotic properties. To evaluate the effect of soy isoflavones on bone loss, 403 early postmenopausal women (54.0±4.0 y) were enrolled in an intent‐to‐treat, multi‐site, 2‐year follow‐up, randomized, double‐blind study with 1/3 on placebo, 1/3 on 80 mg/d of isoflavones, and 1/3 on 120 mg/d of isoflavones along with 1,000 mg/d of CaCO3 and a daily multivitamin with 400 IU of vitamin D. Bone mineral density (BMD) of the whole body (WB), hip and spine and serum bone turnover markers (osteocalcin, bone specific alkaline phosphatase, and cross‐linked N‐telopeptides of type 1 collagen) were measured at baseline and annual intervals. Baseline characteristics were similar in the three groups. A significant protective effect on the decrease in WB BMD was observed with 120 mg/d of soy isoflavones vs. placebo after 1 y (p = 0.027) and 2 y (p = 0.048) of supplementation. No differences were observed in regional BMD measurements or in bone turnover markers. In conclusion, soy isoflavone supplementation reduces the loss of WB BMD at the highest supplementation level, but was not protective at the regional sites. Supported by Initiative for Future Agriculture and Food Systems Grant no. 2001‐52102‐11255 from the USDA CSREES.
Risk of severe depressive mood decreases with improving hemoglobin levels, but only when daytime salivary cortisol concentration is low
Authors: Rahn Maike , Haas Jere D , Hernández‐Cordero Sonia L , Campirano Fabricio A , Villapando Salvador , Rivera Juan
Published: June 2021

Previous research indicates that stressor exposure increases risk of severe depressive mood in iron deficient Hispanic women (Rahn 2007). Iron status, severity of depressive mood (Beck depression inventory, BDI), and salivary cortisol concentration were assessed in 48 female Mexican factory workers from the state of Morelos. Iron status measures were hemoglobin, ferritin, protoporphyrin, MCV and transferrin saturation. Salivary cortisol was sampled as a biological marker of stress for 2 successive days. The area under the cortisol concentration curve (AUC) over 7 daytime hours was estimated. Fatigue was assessed with the Fatigue Severity Scale. Mean age was 29 years; mean hemoglobin was 131 g/L (SD=18) and ranged from 8.8 to 16.1 g/L. Anemia with iron depletion occurred in 25% of subjects, while severe depressive mood (BDI score≥29) was found in 31%. The outcome of the logistic regression analysis was risk of severe depressive mood (BDI ≥29) compared to the reference group (BDI<29). Hemoglobin (continuous) and AUC (<median, ≥median) were combined in an interaction term; additional covariates were fatigue, and household crowding and SES. Women with AUC<median had a 6% decrease (p‐value of subgroup=0.04) in odds of severe depressive mood with every one g/L increase of hemoglobin (p‐value of interaction=0.08); no significant slope was found with AUC≥median.

This research was supported by the NIH predoctoral nutrition training grant 3 T32 DK007158‐29, the Einaudi Center for International Studies and the N.S. Meinig Professorship, Cornell University.
Overweight duration interacts with added salt intake in increasing odds of hypertension among adult women in Cebu, Philippines
Authors: Lee Nanette , Adair Linda
Published: June 2021

Being overweight (OW) and high salt intake are known to increase hypertension (HTN) risk. Less is known about the effect of OW duration on HTN risk and whether it interacts with salt intake. Using a sample of 2,003 Filipino women (ages 35–69 yrs) followed for 22 years (1983–2005), this study examined the independent and joint effects of duration of OW (BMI>=25 kg/m2) and high added salt intake on HTN risk. We used data from the Cebu Longitudinal Health and Nutrition Survey and identified 5 patterns of OW history and duration: OW >15 yrs (19%), OW 7–15 yrs (12%), OW <7 yrs (11%), history of OW but not currently OW (10%) and never OW (48%). Added salt intake was deemed high if above mean values. Adjusting for current BMI, age and other confounders, the odds of being hypertensive increases with longer duration of OW. Odds (95% CI) of HTN were highest among women with longest OW duration: 2.0 (1.2, 3.4) for OW >15 yrs, 1.5 (0.9, 2.4) for OW 7–15 yrs, and 1.1 (0.7, 1.7) for OW <7 yrs compared to never OW women. HTN odds among women with high added salt intake were 1.5 (1.1, 2.1) times that of women with low added salt intake. There is significant interaction between OW duration and added salt intake. The odds of HTN among women OW >15 yrs with high added salt intake were 4.4 (2.4, 8.1) times compared to never OW women with low added salt intake. To reduce HTN prevalence, efforts to prevent earlier weight gain and decrease added salt intake should be strengthened.

Funding: NIH 5 R01 TW05596‐04 and 5 D43 TW00633‐06‐09
Eating patterns and risk for overweight in children with Attention Deficit Hyperactive Disorder (ADHD)
Authors: Barak Anat , McCrory Megan A , Lovejoy Jennifer C , Weber Wendy
Published: June 2021

Children with ADHD may be at increased risk for overweight. Although meal skipping, frequent snacking, and excessive consumption of foods high in fat and sugar have been associated with both a tendency toward obesity and poor behavioral symptoms, the link between ADHD and excess weight is poorly understood. We examined BMI distribution and eating patterns in children with different types of ADHD: combined Inattentive/Hyperactivity (IH; n=13) vs. Inattentive (I; n=8). A retrospective chart review of children with ADHD treated at the

Bastyr Center for Natural Health from 2001–2006 and who completed a 3‐day diet diary was conducted. We found a non‐significant difference between the ADHD subtypes in BMI distribution (27% of IH vs 50% of I children were at risk for overweight). There were no significant differences between ADHD subtypes in dietary intake. However, a low variety of energy weak foods relative to energy dense foods was associated with a higher BMI percentile (r=−0.45 in all children and r=−0.76 in the I group; P=0.05). ADHD symptom severity was not associated with either BMI percentile or dietary intake. This study suggests there may be a relationship between BMI and ADHD subtype, which may be partially explained by dietary variety. Further research is needed to understand the obesity‐ADHD connection.

Grant Funding Source: none
Can variability in energy intake be attributed to one meal versus another?
Authors: Sieber Jessica Lynne , Raynor Hollie , Carriquiry Alicia , Jahns Lisa
Published: June 2021

Objective: Stability of meal patterns has been suggested to be associated with lower body weight. To examine the stability of energy contribution by meal type, estimates of within‐ (WIV) and between‐(BIV) individual variation (WIV) in energy intake by meal was compared to determine which meal accounts for the largest variation in daily energy intake among young adults.

Methods: Mean ± SD and estimated coefficients of variation (CVw, CVb) in energy intake for self‐defined breakfast (B), lunch (L), dinner (D), and snack (S) meals were calculated using a mixed effects regression model. Intake was measured using 7 day food records (FR) entered into NDSR for analysis. Subjects were 105 18–19 yo college students.

Results: Mean daily energy intake was 2180 ± 847 kcal, of which S contributed 20% (438 ± 507 kcal). CVw and CVb for B, L, D, S were 93/57, 74/31, 68/31, and 101/55%, respectively. Ratios of WIV and BIV were 1.6, 2.4, 2.2, and 1.8 for B,L, D, S, respectively.

Conclusion: S were associated with the greatest CVw and D with the least, however, the higher WIV/BIV ratios for L and D suggest that there may be much more variation in these meals. All ratios exceeded unity, suggesting there is greater variation within individuals than between individuals.
Toll‐like receptor‐2 and CD47 co‐stimulatory signaling regulates neutrophil transmigration
Authors: Chin Alex Chung Kyu , Reaves Titus A. , Lee Winston Y. , Peatman Eric J. , Parkos Charles A.
Published: June 2021

Tissue infiltration by neutrophils (PMN) is a hallmark of acute inflammation and is crucial for the rapid removal of microbial pathogens. Previous studies have shown that PMN transmigration is regulated by the cell surface protein CD47, however this phenomenon in the context of microbial invasion and subsequent Toll‐like receptor (TLR) signaling is poorly understood. In this study we assessed the role of TLR2 and CD47 co‐stimulation in regulating PMN transmigration. PMN transepithelial migration (TEM; T84 monolayers) towards the bacterial chemoattractant fMLP was significantly delayed for 30min by 1μM Pam3CSK4 (TLR2/1 agonist), 100nM MALP‐2 (TLR2/6 agonist) or 20μg/ml anti‐human CD47 mAbs (C5/D5). In addition, Pam3CSK4 or MALP‐2 and C5/D5 added together further delayed PMN TEM by 2h. C57BL/6 murine bone marrow‐derived PMN transfilter migration (TFM) towards fNLP was inhibited (50%) by 200nM MALP‐2 or 20μg/ml anti‐mouse CD47 mAbs (MIAP), while, in combination, blocked PMN TFM by 75%. Conversely TFM using TLR2−/− or MyD88−/− bone marrow PMN was not inhibited by MALP‐2 or MIAP. TLR2 agonists did not increase human or murine PMN surface CD47 expression (flow cytometry). Collectively, these findings suggest that TLR activation may serve as “stop” signals, and facilitate antimicrobial functions including CD47‐mediated PMN transmigration.
Ethnicity and differences in mammary myoepithelial cell layers and inflammatory cell infiltration: Implications for differences in tumor development and behavior
Authors: Man Yan‐gao , Sheng Joy , Firpo Adolfo , Zhang Xichen
Published: June 2021

Objective:

The incidence and clinical course of breast cancer vary significantly between Asian and Western females. Despite tremendous intervention efforts focused on tumor cells, the trend has remained unchanged during the past 30 years. This study attempted to examine the tumor surroundings that may contribute to the racial disparity. Methods: Tissue sections from 15 Western and 15 Asian females with similar breast tumors were compared for a panel of tumor suppressor‐ and inflammation‐related markers.

Results:

Compared to their Asian counterparts, Western females had the following unique features: [1] a significantly higher frequency of focal disruptions and lower tumor suppressor expression in myoepithelial (ME) cell layers, [2] significantly higher rate of leukocyte and mast cell infiltration.

Conclusions:

As the ME cell layer is the physical barrier to prevent tumor invasion, and chronic inflammation is a potential tumor promoter, these differences in tumor surroundings may contribute to the observed higher incidence and severity of breast cancer in Western women (Supported by grant 2006CB910505 from the Ministry of Chinese Science and Technology Department, and DAMD17‐01‐1‐0129, DAMD17‐01‐1‐0130, and PC051308 from US Congressionally Directed Medical Research Programs, and BCTR0706983 from The Susan G. Komen Breast Cancer Foundation).
Phosphorylation of beta‐catenin by PKA promotes vascular smooth muscle cell proliferation in response to purinergic receptor stimulation.
Authors: Taurin Sebastien , Dulin Nickolai O.
Published: June 2021

Extracellular ATP stimulates proliferation of vascular smooth muscle cells (VSMC) through activation of P2Y purinergic receptors. We have previously shown that a) ATP stimulates a transient activation of protein kinase A (PKA), which is required for maximal DNA synthesis in VSMC; and b) PKA can phosphorylate beta‐catenin at two novel sites (Ser552 and Ser675) in COS7‐overexpression cell model. Beta‐catenin is a signaling molecule which is regulated through degradation / stabilization mechanism, and which promotes cell proliferation by activation of T cell factor (TCF) transcription factors. In the present study, using the new phospho‐specific antibodies against pSer552 or pSer675 sites of beta‐catenin, we show that ATP can stimulate PKA‐dependent phosphorylation of endogenous beta‐catenin at both of these sites without affecting its expression levels in VSMC. This translates to a PKA‐dependent stimulation of TCF transcriptional activity, in part, through an increased association of phosphorylated (by PKA) beta‐catenin with TCF‐4. Using adenovirus‐mediated transduction of PKA inhibitor, PKI, or of dominant negative TCF‐4 mutant, we show that ATP stimulates cyclin D1 promoter activation, cyclin D1 protein expression and proliferation of VSMC – all in PKA‐ and TCF‐dependent manner. In conclusion, we show a critical role of ATP‐induced phosphorylation of beta‐catenin by PKA in proliferation of VSMC.