Colonic ketogenesis, a microbiota-regulated process, contributes to blood ketones and protects against colitis in mice

Ketogenesis is considered to occur primarily in liver to generate ketones as an alternative energy source for non-hepatic tissues when glucose availability/utilization is impaired. 3-Hydroxy-3-methylglutaryl-CoA synthase-2 (HMGCS2) mediates the rate-limiting step in this mitochondrial pathway. Publicly available databases show marked down-regulation of HMGCS2 in colonic tissues in Crohn's disease and ulcerative colitis. This led us to investigate the expression and function of this pathway in colon and its relevance to colonic inflammation in mice. Hmgcs2 is expressed in cecum and colon. As global deletion of Hmgcs2 showed significant postnatal mortality, we used a conditional knockout mouse with enzyme deletion restricted to intestinal tract. These mice had no postnatal mortality. Fasting blood ketones were lower in these mice, indicating contribution of colonic ketogenesis to circulating ketones. There was also evidence of gut barrier breakdown and increased susceptibility to experimental colitis with associated elevated levels of IL-6, IL-1β, and TNF-α in circulation. Interestingly, many of these phenomena were mostly evident in male mice. Hmgcs2 expression in colon is controlled by colonic microbiota as evidenced from decreased expression in germ-free mice and antibiotic-treated conventional mice and from increased expression in a human colonic epithelial cell line upon treatment with aqueous extracts of cecal contents. Transcriptomic analysis of colonic epithelia from control mice and Hmgcs2-null mice indicated an essential role for colonic ketogenesis in the maintenance of optimal mitochondrial function, cholesterol homeostasis, and cell-cell tight-junction organization. These findings demonstrate a sex-dependent obligatory role for ketogenesis in protection against colonic inflammation in mice.

Chowing down: diet considerations in rodent models of metabolic disease

Diet plays a substantial role in the etiology, progression, and treatment of chronic disease and is best considered as a multifaceted set of modifiable input variables with pleiotropic effects on a variety of biological pathways spanning multiple organ systems. This brief review discusses key issues related to the design and conduct of diet interventions in rodent models of metabolic disease and their implications for interpreting experiments. We also make specific recommendations to improve rodent diet studies to help better understand the role of diet on metabolic physiology and thereby improve our understanding of metabolic disease.

Genetic and Metabolic Determinants of Plasma Levels of ANGPTL8

CONTEXT

ANGPTL8 (A8) plays a key role in determining the tissue fate of circulating triglycerides (TGs). Plasma A8 levels are associated with several parameters of glucose and TG metabolism, but the causality of these relationships and the contribution of genetic variants to differences in A8 levels have not been explored.

OBJECTIVE

To characterize the frequency distribution of plasma A8 levels in a diverse population using a newly-developed enzyme-linked immunosorbent assay (ELISA) and to identify genetic factors contributing to differences in plasma A8 levels.

METHODS

We studied a population-based sample of Dallas County, comprising individuals in the Dallas Heart Study (DHS-1, n = 3538; DHS-2, n = 3283), including 2131 individuals with repeated measurements 7 to 9 years apart (age 18-85 years; >55% female; 52% Black; 29% White; 17% Hispanic; and 2% other). The main outcome measures were associations of A8 levels with body mass index (BMI), plasma levels of glucose, insulin, lipids, and hepatic TGs, as well as DNA variants identified by exome-wide sequencing.

RESULTS

A8 levels varied over a 150-fold range (2.1-318 ng/mL; median, 13.3 ng/mL) and differed between racial/ethnic groups (Blacks > Hispanics > Whites). A8 levels correlated with BMI, fasting glucose, insulin, and TG levels. A variant in A8, R59W, accounted for 17% of the interindividual variation in A8 levels but was not associated with the metabolic parameters correlated with plasma A8 concentrations.

CONCLUSIONS

A8 levels were strongly associated with indices of glucose and TG metabolism, but the lack of association of genetic variants at the A8 locus that impact A8 levels with these parameters indicates that differences in A8 levels are not causally related to the associated metabolic phenotypes.

Current Status of Healthy Aging and Dementia Research: A Symposium Summary

The purpose of the 'First Regional Healthy Aging and Dementia Research Symposium' was to discuss the latest research in healthy aging and dementia research, public health trends related to neurodegenerative diseases of aging, and community-based programs and research studying health, nutrition, and cognition. This symposium was organized by the Garrison Institute on Aging (GIA) of the Texas Tech University Health Sciences Center (TTUHSC), and was held in Lubbock, Texas, October 24-25, 2018. The Symposium joined experts from educational and research institutions across the United States. The two-day Symposium included all GIA staff and researchers. Students, postdoctoral fellows, and faculty members involved in dementia research presented at the Symposium. Healthcare professionals, from geriatricians to social workers working with patients with neurodegenerative diseases, also presented. In addition, experts traveled from across the United States to participate. This event was comprised of multiple sessions, each with several oral presentations, followed by questions and answers, and discussion.

The Nab experiment: A precision measurement of unpolarized neutron beta decay

Neutron beta decay is one of the most fundamental processes in nuclear physics and provides sensitive means to uncover the details of the weak interaction. Neutron beta decay can evaluate the ratio of axial-vector to vector coupling constants in the standard model, λ = gA/gV, through multiple decay correlations. The Nab experiment will carry out measurements of the electron-neutrino correlation parameter a with a precision of δa/a = 10−3 and the Fierz interference term b to δb = 3 × 10−3 in unpolarized free neutron beta decay. These results, along with a more precise measurement of the neutron lifetime, aim to deliver an independent determination of the ratio λ with a precision of δλ/λ = 0.03% that will allow an evaluation of Vud and sensitively test CKM unitarity, independent of nuclear models. Nab utilizes a novel, long asymmetric spectrometer that guides the decay electron and proton to two large area silicon detectors in order to precisely determine the electron energy and an estimation of the proton momentum from the proton time of flight. The Nab spectrometer is being commissioned at the Fundamental Neutron Physics Beamline at the Spallation Neutron Source at Oak Ridge National Lab. We present an overview of the Nab experiment and recent updates on the spectrometer, analysis, and systematic effects.

Early postnatal growth of low birthweight infants in the WIC program

Patterns of early postnatal growth were analyzed among low birthweight infants enrolled in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). Infants were divided into four groups according to their neonatal status: (1) term, normal birthweight (NBW); (2) term, low birthweight (LBW); (3) moderately preterm LBW; and (4) very preterm LBW. Comparison of mean weight and length z-scores indicated that term NBW and very preterm LBW infants were at or near the national reference averages at 8, 12, and 18 months. Term LBW and moderately preterm infants were lighter and shorter than the other two study groups at each visit. Term LBW and moderately preterm infants displayed evidence of catch-up growth during the study period. Catch-up growth was defined as a decrease in the percentage of infants below the 10th percentile for weight. The effect of neonatal body proportions on postnatal growth was investigated in term LBW infants. The infants were divided into two groups based on their ponderal index (PI) at birth (low PI and proportionate PI). Comparison of weight and length z-scores indicated that both groups of term LBW infants improved in z-scores between birth and the first visit (approximately 8 months). However, infants with evidence of asymmetric intrauterine growth restriction (low PI) continued to improve in weight and length z-scores, whereas those with symmetric growth restriction (proportionate PI) remained lighter and shorter.

The positive predictive value of cervical smears in previously screened postmenopausal women: the Heart and Estrogen/progestin Replacement Study (HERS)

BACKGROUND

The benefits and risks of performing annual cervical smears on postmenopausal women are not well defined. The independent effect of hormone replacement therapy on development of cytologic abnormalities is unknown.

OBJECTIVE

To determine the positive predictive value of cervical smears in previously screened postmenopausal women and to determine the effect of oral estrogen plus progestin on incident cervical cytologic abnormalities.

DESIGN

Prospective cohort study (incidence) and randomized, double-blind, placebo-controlled trial (hormone therapy).

SETTING

20 U.S. outpatient and community clinical centers.

PARTICIPANTS

2561 women with a uterus and normal cytologic characteristics at baseline.

INTERVENTIONS

Annual smears; oral conjugated equine estrogens, 0. 625 mg/d, plus medroxyprogesterone acetate, 2.5 mg/d, or identical placebo.

MEASUREMENTS

Incident cytologic abnormalities (atypical squamous cells of undetermined significance, atypical glandular cells of undetermined significance, low-grade squamous epithelial lesion, and high-grade squamous epithelial lesion) and final histologic diagnoses.

RESULTS

The incidence of new cytologic abnormalities in the 2 years following a normal smear was 110 per 4895 person-years (23 per 1000 person-years [95% CI, 18 to 27 per 1000 person-years]). Among the 103 women with known histologic diagnoses, one had mild to moderate dysplasia. The positive predictive value of any smear abnormality identified 1 year after a normal smear, therefore, was 0% (CI, 0% to 5.0%) (0 of 78 women); the positive predictive value of abnormalities found within 2 years was 0.9% (CI, 0.0% to 3.0%) (1 of 110 women). In hormone-treated compared with non-hormone-treated women, the incidence of cytologic abnormalities was nonsignificantly higher (relative hazard, 1.36 [CI, 0.93 to 1.99]), largely because of a nonsignificant 58% greater incidence of atypical squamous cells of undetermined significance (relative hazard, 1.58 [CI, 0.99 to 2.52]).

CONCLUSIONS

Because of a poor positive predictive value, cervical smears should not be performed within 2 years of normal cytologic results in postmenopausal women. Therapy with oral estrogen plus progestin does not significantly affect the incidence of cytologic abnormalities.

Health care social workers' views of ethical issues, practice, and policy in end-of-life care

End-of-life care decision making is perhaps the most difficult practice situation faced by health care social workers. Complex ethical issues arise from decisions regarding use of advancing medical technologies and/or other artificial treatments that may prolong life and/or compromise its quality. NASW has set forth a policy to help guide social workers dealing with end-of-life care decisions and the preservation of client self-determination in these situations. However, the present study (N = 63) revealed that a majority (57%) of social workers were not aware of the existence of, or were only somewhat familiar with the policy. Ethical dilemmas most often faced in end-of-life care situations related primarily to issues of communication between and among patients, families, and professionals. Practitioners indicated that more specific practice guidelines and increased education regarding bioethics and issues of end-of-life care are needed to be effective in assisting patients and families in end-of-life decision making.

Changes in women's fear of success and fear of appearing incompetent in business

The primary purpose of this research was to examine whether fear of success and of appearing incompetent among women have changed recently. Another purpose was to examine whether such fears differed among women who hold Traditional views and those who hold Progressive views about the roles of women in the workplace. The Fear of Success Scale, the Fear of Appearing Incompetent Scale, and the Attitude Toward Women Scale were completed by 61 male and 52 female graduating seniors. Significant differences were found between the groups for scores on the Attitude Toward Women Scale, but none between the sexes for scores on the Fear of Success Scale or the Fear of Appearing Incompetent Scale. Significant differences were found, however, on the latter two scales when women were separated into Traditional and Progressive groups.

[Diagnosis and therapy of acute rejection in patients after orthotopic heart transplantation]

OBJECTIVE

In organ allotransplantation represents a serious problem acute rejection, which is the reaction of recipient organism aimed to reject the transplanted organ.

AIM

To obtain experience in the field of routine long term are of patients after heart transplantation living in Slovakia.

METHOD

33 patients after orthotopic heart transplantation (HTx) were included in our long term care by the 1. June 1996. According to the accepted protocol we make the whole set of examinations is performed. This includes endomyocardial biopsy which is the only reliable method for the detection of rejection and also the criterion of sufficiency of immunosuppressive therapy.

RESULTS

Acute rejection was revealed in 14 (43%) patients.

CONCLUSIONS

Tactics of therapy and the length of the interval to subsequent biopsy were determined according to the histological findings of preceding biopsy, the clinical status and the combination of immunosuppression therapy. (Tab. 2, Ref. 13.)

Venovenous bypass in adult orthotopic liver transplantation: routine or selective use?

BACKGROUND

The role of venovenous bypass (VVB) during orthotopic liver transplantation (OLT) remains controversial. The aims of this study were to evaluate the current role of VVB at all major centers in North America, to examine the results of OLT and complications of VVB between two periods with a strict policy for routine versus selective use of VVB, and to review the literature.

STUDY DESIGN

A survey of 50 major liver transplant centers was conducted using mailed questionnaires. A retrospective chart review was performed for 547 OLT patients having transplantation during two distinct periods with a strict policy for routine versus selective use of VVB at the University of Toronto, Canada, and at Duke University Medical Center, Durham, North Carolina. The literature was reviewed with a focus on the benefits and indications for routine versus selective use of VVB.

RESULTS

Thirty-eight (76%) of 50 centers responded. Sixteen (42%) of them used VVB routinely, with a reported complication rate of 10-30%. Lymphocele and hematoma were the most common complications, but patients having major vascular injury, air embolism, and death were reported. A recent change to selective use of VVB was reported in 30% of the centers (11 of 38). In the Duke-Toronto series, the complication rates were similar between the two periods, at 13.4% and 18.8%, respectively. The outcome of OLT was not influenced by the policy of routine or selective use of VVB.

CONCLUSIONS

There is a trend away from the routine use of VVB during OLT. Intraoperative hemodynamic instability during the hepatectomy and a failed trial of hepatic venous occlusion were the most important criteria for using VVB. We conclude that VVB should be used selectively to avoid associated complications and to decrease operative time and costs.

Human cytotrophoblast differentiation/invasion is abnormal in pre-eclampsia

During human placental development, cytotrophoblast stem cells differentiate and invade the uterus. Simultaneously, the cells modulate their expression of several classes of stage-specific antigens that mark transitions in the differentiation process and play a role in either uterine invasion (integrin cell-extracellular matrix receptors and matrix metalloproteinase-9) or immune interactions (HLA-G). The pregnancy disease pre-eclampsia is associated with shallow cytotrophoblast invasion. Previously we showed, by immunofluorescence localization on placental tissue, that in pre-eclampsia invasive cytotrophoblasts fail to properly modulate their integrin repertoire. This finding suggests possible abnormalities in the differentiation pathway that leads to uterine invasion. Here we used a culture system that supports this differentiation process to compare the differentiative and invasive potential of cytotrophoblasts obtained from control (n = 8, 22 to 38 weeks) and pre-eclamptic (n = 9, 24 to 38 weeks) placentas. In culture, the cells from pre-eclamptic placentas failed to properly modulate alpha1 integrin and matrix metalloproteinase-9 expression at the protein and mRNA levels. Their invasive potential was also greatly reduced. Likewise, the cells failed to up-regulate HLA-G protein and mRNA expression. These results suggest that defective cytotrophoblast differentiation/invasion can have significant consequences to the outcome of human pregnancy (ie, development of pre-eclampsia) and that, by the time delivery becomes necessary, the defect is not reversed by removing the cells from the maternal environment.

[Quality of life after heart transplantation--psychosocial aspects]

The aim of this study was to evaluate psychosocial quality of life after heart transplantation. We examined 29 patients (25 M and 4 F), average age was 43.5 y (18-62 y). The age at time of heart transplantation was 43 years (17-55 y). The time after heart transplantation was 3.3 year (0.3-9 y). Spielberger's Questionnaire of Anxiety, Knobloch's inventory of neuroticism, Freiburg's Personality Inventory and Quality of Life Inventory were used, 33% of patients demonstrated increasing frequency and 29% of patients increasing intensity of neurotic symptoms. 23% of patients presented increasing levels of anxiety (as a state). The personality dimensions (depression, excitability and low emotional stability) displayed high frequency. The results showed that patients were more satisfied with family support, with sexual activities, and less satisfied with financial situation, social activities, social isolations, sleep, memory, excitability, fatigue. 41.5% of patients returned back to work. The results indicate that these psychosocial factors play an important role in quality of life after heart transplantation. That is why if is necessary to dedicate an increasing attention to them. (Tab. 1, Fig. 6, Ref. 14.)

[Dilated cardiomyopathy and heart transplantation]

Authors compare selected demographic, clinical, methodological and laboratory parameters in 20 patients who underwent heart transplantation (HTx) because of dilated cardiomyopathy (DKMP) with those, who have had HTx because of progressive and otherwise unresolved coronary artery disease (KCH). Patients operated because of DKMP were younger than those who underwent HTx for KCH. Women were only in the group of DKMP. Otherwise there were no differences between these two groups. The global analysis showed, that the majority of patients after HTx were asymptomatic. However, high incidence of obesity, hyperlipoproteinemia, cytopoenia, renal and hepatal dysfunction were found. Finally the authors presented an overview of standard chronic therapy after HTx and proposed some approaches to undesirable habits and disorders which aggravated the prognosis of the patients after HTx.

Cross cultural communication to help physician assistants provide unbiased health care

Teaching cross cultural communication typically involves instruction in differences between groups. As part of this course in cross cultural communication, six specific underserved population groups are introduced to students as a cultural experience. Additionally, instruction is provided to sensitize students to their personal biases and prejudices through videotaped mock interviews. The combination of instruction and experience forms a paradigm for teaching cross cultural communication in a way that has personal and immediate impact on faculty members and students. The model, "Differences + Discomforts = Discoveries," inhibits factionalizing and promotes depth of knowledge about underserved groups as well as personal awareness of prejudicial feelings. As a result, students learn techniques to provide unbiased health care to these, and other, populations.

Effects of fetal anemia on PO2 difference between uterine venous and umbilical venous blood

In the fetus, the functional equivalent of the alveolar-arterial blood PO2 difference is the uterine venous-umbilical venous blood PO2 difference. Generally, factors that affect one of the venous blood PO2s produce equivalent effects on the other. We previously showed that fetal anemia produces increases in umbilical venous blood PO2. To determine whether this increase was associated either with equivalent increases in uterine venous blood PO2 or with reductions in the uterine venous-umbilical venous PO2 difference, we studied eight chronically catheterized pregnant sheep and fetal lambs. Measurements of O2 gas tensions and O2 saturations, uterine and umbilical blood flows, and uterine, fetal, and placental O2 consumptions were made in animals with normal fetal hematocrits and during reductions in fetal hematocrit of 35% (moderate fetal anemia) or 60% (severe fetal anemia). Fetal anemia produced reductions in the uterine venous-umbilical venous blood PO2 difference; in some cases the PO2 difference was less than 2 mmHg (compared with normal values of 20 mmHg). The development of both moderate and severe fetal anemia had no effect on uterine and umbilical blood flows or placental O2 consumption but did reduce total uterine and fetal O2 consumption. These data indicate that fetal anemia induces changes in placental gas transport. These changes may be due to improvements in gas diffusion, reductions in perfusion mismatching, or reductions in vascular shunting. Our data further indicate that placental O2 consumption rate, which is high in normal pregnant sheep, plays no role in the maintenance of the uterine venous-umbilical venous blood PO2 difference in pregnant sheep.

The need to expand minority recruitment

Involvement of minorities in the PA profession does not match the changing demographics of the United States. A concrete affirmative action plan should be developed to recruit more minorities into the profession to help meet the health care needs of underserved populations.

Effects of reductions in hemoglobin-oxygen affinity and hematocrit level on oxygen consumption and acid-base state in fetal lambs

To determine whether the high oxygen affinity of fetal blood, compared with that of the adult, is advantageous to the fetus during fetal anemia we studied 16 chronically catheterized fetal lambs. Half of the lambs had hemoglobin-oxygen affinity reduced acutely by isovolemic exchange transfusion with fresh adult whole blood; the other half served as controls. In both groups of fetuses, we measured fetal oxygen delivery, oxygen consumption, and acid-base state at normal fetal hematocrit levels and during reductions in the hematocrit level of 30% (moderate anemia) and 60% (severe anemia) produced by isovolemic exchange transfusions with plasma. At normal fetal hematocrit levels, reductions in hemoglobin-oxygen affinity had no effect on fetal oxygen consumption or acid-base state. During moderate anemia, fetal oxygen delivery decreased in both series of fetuses, but oxygen consumption and base excess fell only in those fetuses whose circulations contained adult hemoglobin. During severe anemia, oxygen consumption and base excess decreased in both groups of fetuses, although these changes were more pronounced in fetuses with adult hemoglobin than in those with fetal hemoglobin. Our data indicate that, even though a high hemoglobin-oxygen affinity may not be essential to a healthy fetus, it is critical for normal metabolism in a fetus subjected to a hypoxic stress such as anemia.