Modulation of immune responses to Mycobacterium bovis in cattle depleted of WC1(+) gamma delta T cells

It is accepted that cell-mediated immune responses predominate in mycobacterial infections. Many studies have shown that CD4(+) T cells produce Th1 cytokines, such as gamma interferon (IFN-gamma), in response to mycobacterial antigens and that the cytolytic activity of CD8(+) cells toward infected macrophages is important. However, the extent and manner in which gamma delta T cells participate in this response remain unclear. In ruminants, gamma delta T cells comprise a major proportion of the peripheral blood mononuclear cell population. We have previously shown that WC1(+) gamma delta T cells are involved early in Mycobacterium bovis infection of cattle, but their specific functions are not well understood. Here we describe an in vivo model of bovine tuberculosis in which the WC1(+) gamma delta T cells were depleted from the peripheral circulation and respiratory tract, by infusion of WC1(+)-specific monoclonal antibody, prior to infection. While no effects on disease pathology were observed in this experiment, results indicate that WC1(+) gamma delta T cells, which become significantly activated (CD25(+)) in the circulation of control calves from 21 days postinfection, may play a role in modulating the developing immune response to M. bovis. WC1(+)-depleted animals exhibited decreased antigen-specific lymphocyte proliferative response, an increased antigen-specific production of interleukin-4, and a lack of specific immunoglobulin G2 antibody. This suggests that WC1(+) gamma delta TCR(+) cells contribute, either directly or indirectly, toward the Th1 bias of the immune response in bovine tuberculosis--a hypothesis supported by the decreased innate production of IFN-gamma, which was observed in WC1(+)-depleted calves.     

Experimental mechanical and histologic evaluation of the Kennedy ligament augmentation device

Reconstruction of the knee with a chronic injury to the anterior cruciate ligament is an unsolved problem. Biologic graft substitutes have failed to maintain knee stability in the longer postreconstruction intervals. In an attempt to overcome the limitations in graft performance, synthetic materials have been proposed to augment the biologic tissue. In this study, a 6-mm polypropylene braid Ligament Augmentation Device (LAD) possessing a tensile strength of 1500 N and excellent fatigue and creep properties was investigated as an adjunct to the MacIntosh/Marshall Over-the-Top repair. A two-year animal study of 54 adult goats was conducted in which experimental ACL defects were created and reconstructed with a transplant consisting of a portion of the rectus femoris tendon, prepatellar tissue, and the central one-third of the patellar tendon. The goats were equally divided between nonaugmented and LAD-augmented groups and sacrificed at three, six, 12, and 24 months after surgery. Mechanically, the augmented transplants were substantially stronger at the time of initial implantation (364N versus 26N) and again at two years (841N versus 528N). Intermediate times did not demonstrate a difference in strength. Histologically, the augmented transplants consisted of a loosely organized fibrous capsule surrounding the LAD. At 24 months, "insertion fibers" were noted to provide continuity between the fibrous tissue and bone on both the tibia and femur.     

Behavioral trait associated with conditioned immunity

Inbred strains of mice were tested for their activity in an open field. Animals selected for high or low activity ("tails" of the normal distribution) were further inbred through nine generations (brother x sister) with further selection at each generation. Reciprocal skin grafts between the two groups were performed to ensure that little/no genetic drift occurred. Using a cyclophosphamide:saccharin conditioning paradigm (R. Ader & N. Cohen (1975) Psychosom. Med. 37, 333-342) we show that mice preselected for high activity in an open field were those in which it was most easy to demonstrate conditioned immunosuppression. There was no difference in the conditionability of the two groups as assessed by taste aversion. By use of a cross-fostering design we conclude that immunological conditioning (in adult mice) can be affected by a characteristic of the nursing mother which is associated with activity in an open-field trial.     

Reperfusion arrhythmias during coronary reperfusion therapy in man. Clinical and angiographic correlations

We hypothesized that patients suffering acute myocardial infarction who have reperfusion arrhythmias (RPA) during intracoronary streptokinase infusion (ICSK) would have different clinical and angiographic characteristics and a larger infarction size than those who achieved reperfusion without RPA. Of 35 patients who received intracoronary streptokinase, 27 had successful reperfusion documented by angiography. Successful reperfusion was accompanied by RPA in eight patients and no RPA in 19 patients. RPA included episodes of ventricular tachycardia in one, idioventricular rhythm in four, junctional bradycardia in one, or AV block in two patients which occurred at the time of reperfusion. Myocardial infarction size was calculated using creatine kinase-MB (CK-MB) isoenzyme time activity curves using standard methods. The mean CK-MB g equivalents (eq) for those with RPA was 71 +/- 25 (+/- 1 SD) and for those with no RPA was 45 +/- 24 (p less than .04). In patients with RPA, ejection fraction rose 5 +/- 14 percentage points before discharge, but fell 10 +/- 13 points in those with RPA (p less than .03). There was no difference between groups in total dose of streptokinase, final degree of stenosis of the affected vessel, reocclusion rate, or time from onset of symptoms to reperfusion. We conclude that patients suffering acute myocardial infarction who have RPA during ICSK in most cases have a larger infarction site or a more "stunned myocardium," as indicated by greater CK-MB release and fall in ejection fraction which is not due to increased time of ischemia.     

Measuring and understanding public awareness of fetal alcohol spectrum disorders in Alberta,Canada

Journal of Public Health - Efforts to increase public awareness about fetal alcohol spectrum disorders (FASD) sometimes fail to translate into direct changes in attitudes or behaviors regarding...     

Acceptability and Feasibility of a 13-Week Pilot Randomised Controlled Trial Testing the Effects of Incremental Doses of Beetroot Juice in Overweight and Obese Older Adults

Nitrate-rich food can increase nitric oxide production and improve vascular and brain functions. This study examines the feasibility of a randomised controlled trial (RCT) testing the effects of prolonged consumption of different doses of dietary nitrate (NO₃⁻) in the form of beetroot juice (BJ) in overweight and obese older participants. A single-blind, four-arm parallel pilot RCT was conducted in 62 overweight and obese (30.4 ± 4 kg/m²) older participants (mean ± standard deviation (SD), 66 ± 4 years). Participants were randomized to: (1) high-NO₃⁻ (HN: 2 × 70 mL BJ/day) (2) medium-NO₃⁻ (MN: 70 mL BJ/day), (3) low-NO₃⁻ (LN: 70 mL BJ on alternate days) or (4) Placebo (PL: 70 mL of NO₃⁻-depleted BJ on alternate days), for 13 weeks. Compliance was checked by a daily log of consumed BJ, NO₃⁻ intake, and by measuring NO₃⁻ and NO₂⁻ concentrations in plasma, saliva, and urine samples. Fifty participants completed the study. Self-reported compliance to the interventions was >90%. There were significant positive linear relationships between NO₃⁻ dose and the increase in plasma and urinary NO₃⁻ concentration (R² = 0.71, p < 0.001 and R² = 0.46 p < 0.001, respectively), but relationships between NO₃⁻ dose and changes in salivary NO₃⁻ and NO₂⁻ were non-linear (R² = 0.35, p = 0.002 and R² = 0.23, p = 0.007, respectively). The results confirm the feasibility of prolonged BJ supplementation in older overweight and obese adults.     

Effects of COVID-19 on University Student Food Security

During COVID-19 restrictions in spring 2020, college students experienced closed dormitories and increased unemployment and many students moved in with their families. College students were vulnerable to food insecurity pre-pandemic and this study examined how the living situations and food security status changed for Midwestern university students due to COVID-19 restrictions. An email survey administered to Iowa State University students between the ages of 18 and 30 who physically attended campus prior to its closure produced 1434 responses. Students living with a parent or guardian increased by 44% and were less likely to experience food insecurity or less likely to work. They had lower stress and ate more home-cooked meals. Students living on their own had higher rates of food insecurity, greater stress, poorer health status, higher cooking self-efficacy, and worked more hours. Seventeen percent of all students were food insecure; related factors were non-White ethnicity, lower cooking self-efficacy, undergraduate status, receipt of financial aid, employment, stress, living in the same situation as before the campus closure, and consumption of more take-out or fast food. These individuals had more barriers to food access. Knowledge of these factors provide useful information to inform future support services for this population in similar conditions.     

Does Perceived Quality of Care Moderate Postpartum Depression? A Secondary Analysis of a Two-Stage Survey

Maternal and Child Health Journal - The purpose of this study was to examine if women’s perceptions of the quality of hospital care during childbirth moderate their risks for symptoms of...     

Rift Valley Fever and Crimean-Congo Hemorrhagic Fever Viruses in Ruminants,Jordan

The epidemiology of Rift Valley fever virus (RVFV) and Crimean-Congo hemorrhagic fever virus (CCHFV) in Jordan is unknown. Our investigation showed 3% of 989 tested dairy cattle, sheep, and goats were RVFV seropositive and 14% were CCHFV seropositive. Ongoing surveillance is needed to assess risk to humans and protect public health.