Publications by authors named "Spears J"

Copper is an essential trace element that functions in a diverse array of biochemical processes that include mitochondrial respiration, neurotransmitter biogenesis, connective tissue maturation, and reactive oxygen chemistry. The Ctr1 protein is a high-affinity Cu(+) importer that is structurally and functionally conserved in yeast, plants, fruit flies, and humans and that, in all of these organisms, is localized to the plasma membrane and intracellular vesicles. Although intestinal epithelial cell-specific deletion of Ctr1 in mice demonstrated a critical role for Ctr1 in dietary copper absorption, some controversy exists over the localization of Ctr1 in intestinal epithelial cells in vivo.

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Many cytochrome P450 enzymes are involved in xenobiotic metabolism and elimination. In humans, genetic variation in some of these enzymes contributes to inter-individual drug responses, sometimes having significant clinical effects. Transcript levels of eight P450 genes were evaluated in liver to investigate potential differences in breed and sex in cattle.

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Thirty-six Angus and Angus×Simmental steers were fed one of three dietary treatments; (1) control (no supplemental B), (2) 5 mg supplemental B/kg, and (3) 15 mg supplemental B/kg for 47 days to determine the effects of dietary boron (B) on disease resistance following an inoculation with bovine herpesvirus type-1 (BHV-1). On day 34 of the study steers were inoculated intranasally with BHV-1. Rectal temperatures began to elevate at day 2, and plasma tumor necrosis factor-α concentrations increased (P<0.

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A 56-d experiment was designed to examine the effect of high dietary Fe on metal transporters involved in Fe and Mn metabolism. Fourteen weaned Holstein calves were stratified by weight and randomly assigned to 1 of 2 treatments: 1) no supplemental Fe (normal Fe) or 2) 750mg of supplemental Fe/kg of dry matter (high Fe). Jugular blood was collected on d 0, 35, and 56.

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To investigate the effects of dietary iron (Fe) and age on Fe metabolism, we used 36 weaned barrows in a 2 x 3 design with 2 concentrations of dietary Fe [97 (control) and 797 (high Fe) mg Fe/kg dry matter] and 3 time points of tissue collection (after 21, 42, or 63 d on diets). Pigs were weighed and bled on d 0, 20, 41, and 62. High Fe reduced feed efficiency but did not affect pig weight gain.

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Objective: Dural arteriovenous fistulae (DAVF) of the hypoglossal canal region are rare lesions. We describe three cases of DAVF of the hypoglossal canal presenting with ocular symptoms and discuss the endovascular management options.

Methods: Three consecutive patients with DAVF of the hypoglossal canal region presented with proptosis, chemosis and disturbances of extra-ocular mobility.

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A 493-d study was conducted to determine the impact of a severe, long-term Cu deficiency on Fe metabolism in beef cattle. Twenty-one Angus calves were born to cows receiving one of the following treatments: 1) adequate Cu (+Cu), 2) Cu deficient (-Cu), and 3) Cu deficient plus high Mn (-Cu+Mn). Copper deficiency was induced through the addition of 2 mg of Mo/kg of DM.

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Four hundred thirty-two crossbred yearling steers (339 kg +/- 4.8) were used to investigate the effects of water quality and dietary potassium concentration and source on feedlot performance and carcass merit. The study was conducted using a 2 x 3 factorial treatment arrangement.

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Copper chaperone for Cu, Zn superoxide dismutase (CCS) has been shown to be reflective of Cu status in mice and rats. The objective of this study was to evaluate liver and erythrocyte CCS as an indicator of Cu status in beef cattle (Exp. 1), and to test the acute-phase properties of CCS under conditions of inflammation (Exp.

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Though altruism and patient advocacy are promoted in medical education curricula, students are given few opportunities to develop these skills. Student-run clinics focusing on the health needs of the underserved can provide important health services to needy patients while providing students with career-influencing primary care experiences. The Columbia-Harlem Homeless Medical Partnership (CHHMP)-a project initiated by medical students to provide primary care to Northern Manhattan's homeless population-serves as a new model of service learning in medical education.

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Background: HHT is an autosomal dominant disease with an estimated prevalence of at least 1/5000 which can frequently be complicated by the presence of clinically significant arteriovenous malformations in the brain, lung, gastrointestinal tract and liver. HHT is under-diagnosed and families may be unaware of the available screening and treatment, leading to unnecessary stroke and life-threatening hemorrhage in children and adults.

Objective: The goal of this international HHT guidelines process was to develop evidence-informed consensus guidelines regarding the diagnosis of HHT and the prevention of HHT-related complications and treatment of symptomatic disease.

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To investigate the effects of dietary iron (Fe) on manganese (Mn) metabolism, 24 weaned pigs (21 d old) were blocked by litter and weight and randomly assigned to the following treatments: 1) no supplemental Fe [low Fe (L-Fe)]; 2) 100 mg supplemental Fe/kg [adequate Fe (A-Fe)]; and 3) 500 mg supplemental Fe/kg [high Fe (H-Fe)]. The basal diet was analyzed to contain 20 mg Fe/kg. Tissues were harvested after 32 d of feeding.

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High dietary Fe can negatively affect absorption of other minerals and cause tissue damage through the production of free radicals. Cattle are often exposed to high dietary Fe, and soil ingestion may represent a major dietary source of Fe. Iron in soil is often found in the ferric form bound in insoluble complexes; however, exposure to an acidic environment similar to that occurring during silage fermentation may cause this Fe to be reduced to the more soluble ferrous form.

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Thirty-six Angus and Angus x Simmental cross steers (initial BW 269.5 +/- 22.3 kg) were used to determine the effects of dietary boron (B) on performance and immune function.

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Introduction: The purpose of this paper is to evaluate the Silver Bullet Wound Closure Device (SBWCD, Boehringer Laboratories, Norristown, PA), a new device for delayed primary closure of fasciotomy wounds.

Materials And Methods: A retrospective review was performed over a period of 36 months of all patients with an upper extremity fasciotomy that could not be closed primarily. Cases that underwent fasciotomy closure with the SBWCD were separated from the patients that had a split thickness skin graft (STSG).

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A study was conducted evaluating the effect of long-term Cu deficiency, with or without high Mn, on growth, gene expression and Cu status of beef cattle. Twenty-one Angus calves were born to cows receiving one of the following treatments: (1) 10 mg supplemental Cu/kg DM (+Cu); (2) no supplemental Cu and 2 mg Mo/kg DM ( - Cu); (3) - Cu diet plus 500 mg supplemental Mn/kg DM ( - Cu+Mn). Calves were weaned at approximately 183 d of age and individually fed throughout the growing and finishing phases.

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Objective: Resistant maltodextrin has been shown to increase fecal bulk by resisting digestion and being partially fermented by colonic bacteria to short-chain fatty acids (SCFA). The objective of this experiment was to determine potential prebiotic effects, gastrointestinal tolerance, and fecal characteristics of free-living humans fed a novel resistant maltodextrin or a normal maltodextrin control.

Methods: Subjects (n = 38) were enrolled in a randomized, double-blind study where they were assigned to one of three daily treatments: 15 g maltodextrin; 7.

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An Mn for Cu substitution on cellular prion proteins (PrP(c)) in the brain that results in biochemical changes to PrP(c) has been implicated in the pathogenesis of transmissible spongiform encephalopathies. Recent research in the mature bovine does not support this theory. The present study tested this hypothesis by using progeny from gestating cows receiving Cu-deficient diets or Cu-deficient diets coupled with high dietary Mn.

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The proliferation of new endovascular devices and therapeutic strategies calls for a prudentand rational evaluation of their clinical benefit. This evaluation must be done in an effective manner and in collaboration with industry. Such research initiative requires organisation a land methodological support to survive and thrive in a competitive environment.

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Background: Cancer patients value emotional support but may encounter difficulties in accessing appropriate sources of support. This study explored the emotional support, as perceived by patients, that ward nurses give to sarcoma patients at a large cancer centre.

Methods: A purposive sample of five sarcoma patients who had experienced numerous admissions throughout their chemotherapy took part.

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A number of antioxidants and trace minerals have important roles in immune function and may affect health in transition dairy cows. Vitamin E and beta-carotene are important cellular antioxidants. Selenium (Se) is involved in the antioxidant system via its role in the enzyme glutathione peroxidase.

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Uptake and transport of Zn from (65)Zn-labeled ZnSO(4) and Zn proteinate (ZnProt) by ruminal and omasal epithelia were examined by using a parabiotic chamber system. Uptake was measured during a 4-h incubation with 10, 20, or 200 microM Zn as ZnSO(4) or ZnProt in the mucosal buffer (pH 6.0, Krebs-Ringer phosphate).

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Phytate P utilization from soybean meal (SBM) included in broiler diets has been shown to be poor and highly dependent on dietary Ca intake. However, the effect of Ca on P utilization and on the optimal ratio of Ca to nonphytate P (Ca:NPP) when diets contained varying levels of phytate has not been clearly shown and was the objective of this research. A factorial treatment structure was used with 4 dietary Ca levels from 0.

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The adjoint form of the photon transport equation is applied to a generalized fluorescence detection problem, and its accuracy is empirically tested. This approach can be interpreted as mathematically reversing the temporal flow of fluorescent photons; that is, they are tracked from the detector back to potential sites of origin in the scattering medium. The result is a distribution of potential fluorescing sites that, when properly normalized, gives a probability field of the relative importance of the photon starting position and direction to the resulting signal.

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