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1.
Regul Toxicol Pharmacol ; 114: 104669, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32360443

ABSTRACT

Pectin is a fermentable soluble fiber that can be used as a thickener in formulas for infants and young children. The Joint FAO/WHO Expert Committee on Food Additives concluded that pectin is not of concern for inclusion in infant formula at up to 0.2%. As part of the safety assessment of the suitability of pectin for young infants (≤12 weeks of age), we conducted a 3-week dietary study in a neonatal pig model to 1) investigate the impact of pectin at different doses on neonatal pigs' growth and 2) explore the potential explanation for the dose response. Male and female neonatal pigs were fed milk replacer containing 0, 0.2%, or 1% pectin beginning on postnatal day 2 for 21 days. Body weight, feed intake, and apparent ileal digestibility of dry matter, crude protein, and energy were reduced in pigs fed diets containing 1% pectin (P < 0.01) but not in pigs fed with 0.2% pectin. These data indicate that inclusion of pectin in the diet at 0.2%, equivalent to 704 mg/kg BW/day is safe, well tolerated, and did not result in any adverse health effects in this neonatal pig study.


Subject(s)
Animal Feed , Dietary Fiber/pharmacology , Digestion/drug effects , Milk/chemistry , Nutrients/pharmacology , Pectins/pharmacology , Swine/growth & development , Swine/metabolism , Animal Nutritional Physiological Phenomena , Animals , Animals, Newborn/growth & development , Dietary Fiber/administration & dosage , Dietary Supplements , Dose-Response Relationship, Drug , Female , Male , Models, Animal , Nutrients/administration & dosage , Pectins/administration & dosage , Time Factors
2.
Animal ; 13(5): 1000-1008, 2019 May.
Article in English | MEDLINE | ID: mdl-30322418

ABSTRACT

Trace minerals have important roles in immune function and oxidative metabolism; however, little is known about the relationships between supplementation level and source with outcomes in dairy cattle. Multiparous Holstein cows (n=48) beginning at 60 to 140 days in milk were utilized to determine the effects of trace mineral amount and source on aspects of oxidative metabolism and responses to intramammary lipopolysaccharide (LPS) challenge. Cows were fed a basal diet meeting National Research Council (NRC) requirements except for no added zinc (Zn), copper (Cu) or manganese (Mn). After a 4-week preliminary period, cows were assigned to one of four topdress treatments in a randomized complete block design with a 2×2 factorial arrangement of treatments: (1) NRC inorganic (NRC levels using inorganic (sulfate-based) trace mineral supplements only); (2) NRC organic (NRC levels using organic trace mineral supplements (metals chelated to 2-hydroxy-4-(methythio)-butanoic acid); (3) commercial inorganic (approximately 2×NRC levels using inorganic trace mineral supplements only; and (4) commercial organic (commercial levels using organic trace mineral supplements only). Cows were fed the respective mineral treatments for 6 weeks. Treatment effects were level, source and their interaction. Activities of super oxide dismutase and glutathione peroxidase in erythrocyte lysate and concentrations of thiobarbituric acid reactive substances (TBARS) and total antioxidant capacity (TAC) in plasma were measured as indices of oxidative metabolism. Effects of treatment on those indices were not significant when evaluated across the entire experimental period. Plasma immunoglobulin G level was higher in cows supplemented with organic trace minerals over the entire treatment period; responses assessed as differences of before and after Escherichia coli J5 bacterin vaccination at the end of week 2 of treatment period were not significant. Cows were administered an intramammary LPS challenge during week 5; during week 6 cows fed commercial levels of Zn, Cu and Mn tended to have higher plasma TAC and cows fed organic sources had decreased plasma TBARS. After the LPS challenge, the extent and pattern of response of plasma cortisol concentrations and clinical indices (rectal temperature and heart rate) were not affected by trace mineral level and source. Productive performance including dry matter intake and milk yield and composition were not affected by treatment. Overall, results suggest that the varying level and source of dietary trace minerals do not have significant short-term effects on oxidative metabolism indices and clinical responses to intramammary LPS challenge in midlactation cows.


Subject(s)
Cattle/physiology , Dietary Supplements , Milk/metabolism , Minerals/administration & dosage , Trace Elements/administration & dosage , Animal Feed , Animals , Antioxidants/metabolism , Copper/administration & dosage , Diet/veterinary , Female , Lactation/drug effects , Lipopolysaccharides/administration & dosage , Manganese/administration & dosage , Oxidation-Reduction , Zinc/administration & dosage
3.
Physiother Theory Pract ; 31(7): 518-26, 2015.
Article in English | MEDLINE | ID: mdl-26395829

ABSTRACT

BACKGROUND: Freezing of gait (FOG) is a serious gait disorder affecting up to two-thirds of people with Parkinson's disease (PD). Cueing has been explored as a method of generating motor execution using visual transverse lines on the floor. However, the impact of a laser light visual cue remains unclear. OBJECTIVE: To determine the biomechanical effect of a laser cane on FOG in a participant with PD compared to a healthy age- and gender-matched control. METHODS: The participant with PD and healthy control were given a task of initiating gait from standing. Electromyography (EMG) data were collected from the tibialis anterior (TA) and the medial gastrocnemius (GS) muscles using an 8-channel system. A 10-camera system (Qualisys) recorded movement in 6 degrees of freedom and a calibrated anatomical system technique was used to construct a full body model. Center of mass (COM) and center of pressure (COP) were the main outcome measures. RESULTS: The uncued condition showed that separation of COM and COP took longer and was of smaller magnitude than the cued condition. EMG activity revealed prolonged activation of GS, with little to no TA activity. The cued condition showed earlier COM and COP separation. There was reduced fluctuation in GS, with abnormal, early bursts of TA activity. Step length improved in the cued condition compared to the uncued condition. CONCLUSION: Laserlight visual cueing improved step length beyond a non-cued condition for this patient indicating improved posture and muscle control.


Subject(s)
Cues , Gait , Lasers , Motor Activity , Muscle, Skeletal/innervation , Parkinson Disease/therapy , Photic Stimulation/instrumentation , Visual Perception , Biomechanical Phenomena , Electromyography , Humans , Image Interpretation, Computer-Assisted , Imaging, Three-Dimensional , Male , Middle Aged , Parkinson Disease/diagnosis , Parkinson Disease/physiopathology , Parkinson Disease/psychology , Treatment Outcome
4.
J Dairy Sci ; 95(8): 4568-77, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22818471

ABSTRACT

The aim of this study was to compare effects of inorganic sulfate versus chelated forms of supplemental Cu, Mn, and Zn on milk production, plasma and milk mineral concentrations, neutrophil activity, and antibody titer response to a model vaccination. Holstein cows (n=25) were assigned in 2 cohorts based on calving date to a 12-wk randomized complete block design study. The first cohort consisted of 17 cows that had greater days in milk (DIM; mean of 77 DIM at the start of the trial) than the second cohort of 8 cows (32 DIM at the start of the trial). Diets were formulated to supplement 100% of National Research Council requirements of Cu, Mn, and Zn by either inorganic trace minerals (ITM) in sulfate forms or chelated trace minerals (CTM) supplied as metal methionine hydroxy analog chelates, without accounting for trace mineral contribution from other dietary ingredients. Intake and milk production were recorded daily. Milk composition was measured weekly, and milk Cu, Mn, and Zn were determined at wk 0 and 8. Plasma Cu and Zn concentrations and neutrophil activity were measured at wk 0, 4, 8, and 12. Neutrophil activity was measured by in vitro assays of chemotaxis, phagocytosis, and reactive oxygen species production. A rabies vaccination was administered at wk 8, and vaccine titer response at wk 12 was measured by both rapid fluorescent focus inhibition test and ELISA. Analyzed dietary Cu was 21 and 23mg/kg, Mn was 42 and 46mg/kg, and Zn was 73 and 94mg/kg for the ITM and CTM diets, respectively. No effect of treatment was observed on milk production, milk composition, or plasma minerals. Dry matter intake was reduced for CTM compared with ITM cows, but this was largely explained by differences in body weight between treatments. Milk Cu concentration was greater for CTM than ITM cows, but this effect was limited to the earlier DIM cohort of cows and was most pronounced for multiparous compared with primiparous cows. Measures of neutrophil function were unaffected by treatment except for an enhancement in neutrophil phagocytosis with the CTM treatment found for the later DIM cohort of cows only. Rabies antibody titer in CTM cows was 2.8 fold that of ITM cows as measured by ELISA, with a trend for the rapid fluorescent focus inhibition test. Supplementation of Cu, Mn, and Zn as chelated sources may enhance immune response of early lactation dairy cows compared with cows supplemented with inorganic sources.


Subject(s)
Cattle/immunology , Metals, Heavy/administration & dosage , Sulfates/administration & dosage , Animals , Antibodies, Viral/blood , Chelating Agents/administration & dosage , Cohort Studies , Copper/administration & dosage , Copper/immunology , Eating/immunology , Female , Lactation , Manganese/administration & dosage , Manganese/immunology , Metals, Heavy/immunology , Milk/metabolism , Rabies Vaccines/administration & dosage , Random Allocation , Sulfates/immunology , Zinc/administration & dosage , Zinc/immunology
5.
Poult Sci ; 88(1): 118-31, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19096066

ABSTRACT

Leg problems and resulting mortality can exceed 1% per week in turkey toms starting at approximately 15 wk of age. Dietary supplementation of organic trace minerals (MIN) and 25-hydroxycholecalciferol (HyD) may improve performance, decrease incidence of leg abnormalities, and increase bone strength. Nicholas 85X700 toms were assigned to 4 treatments consisting of a factorial arrangement of 2 concentrations of MIN (0 and 0.1% of Mintrex P(Se), which adds 40, 40, 20, and 0.3 mg/kg of Zn, Mn, Cu, and Se, respectively) and 2 concentrations of HyD (0 and 92 microg/kg of HyD). Diets were formulated to be equal in nutrient content and fed ad libitum as 8 feed phases. Feed intake and BW were measured at 6, 12, 15, 17, and 20 wk of age. Valgus, varus, and shaky leg defects were determined at 12, 15, 17, and 20 wk of age. Tibia and femur biomechanical properties were evaluated by torsion and bending tests at 17 wk of age. There were no treatment effects on BW. Only MIN significantly improved feed conversion ratio through to 20 wk of age. Cumulative mortality at 3 wk of age was greater among the MIN birds, but it was lower by 20 wk (P = 0.085). The MIN decreased the incidence of varus defects at 17 wk of age; shaky leg at 12, 15, and 17 wk of age; and valgus defects at 15, 17, and 20 wk of age. There were no MIN x HyD interaction effects on individual gait problems. Maximum load and the bending stress required for tibias to break in a 4-point assay were increased with MIN supplementation, especially when HyD was also added. Maximum shear stress at failure of femoral bones in a torsion assay was increased by supplementation with both MIN and HyD together. Dietary supplementation of MIN and HyD may improve biomechanical properties of bones. Dietary MIN supplementation may improve feed conversion of turkeys, likely by decreasing leg problems.


Subject(s)
Calcifediol/pharmacology , Hindlimb/pathology , Lameness, Animal/drug therapy , Trace Elements/pharmacology , Turkeys/growth & development , Animal Feed/analysis , Animal Nutritional Physiological Phenomena , Animals , Biomechanical Phenomena , Bone Development/drug effects , Bone and Bones/drug effects , Diet , Dietary Supplements , Male , Walking/physiology
6.
Poult Sci ; 86(5): 877-87, 2007 May.
Article in English | MEDLINE | ID: mdl-17435021

ABSTRACT

Mintrex Zn, Mintrex Cu, and Mintrex Mn organic trace minerals contain 16% Zn, 15% Cu, and 13% Mn with 80, 78, and 76% 2-hydroxy-4-(methylthio)butanoic acid (HMTBA) by weight as the organic ligand, respectively. Our objective was to determine if HMTBA from Mintrex was fully available as a Met source. In experiment 1, thirty-six broilers (7 to 10 d old) were orally gavaged with methyl-(14)C-labeled HMTBA, either as free HMTBA (Alimet feed supplement) or Zn bis(-2-hydroxy-4-methylthiobutyrate) (Mintrex Zn). Radiolabel incorporation from either source into protein was measured as a marker of bioavailable Met activity. Results demonstrated that the HMTBA from Mintrex Zn was equally available as free HMTBA to support protein synthesis. In experiment 2, five hundred seventy-six 1-d-old broilers were allotted to 12 dietary treatments (TRT) for a 21-d growth assay. A TSAA-deficient diet containing 0.70% total TSAA (TRT 1) was supplemented with 0.05, 0.10, 0.15, and 0.20% free HMTBA (TRT 2 to 5) to establish the standard Met response curve. Treatment 6 was analogous to TRT 2 but had an additional 160 ppm Zn, 80 ppm Cu, and 160 ppm Mn as sulfates. Treatments 7 to 12 were identical to TRT 2 but supplemented with 40 or 160 ppm Zn from Mintrex Zn, 20 or 80 ppm Cu from Mintrex Cu, or 40 or 160 ppm Mn from Mintrex Mn, respectively. For TRT 1 through 6, growth performance increased due to increasing Met addition (P < 0.01) but not to increasing inorganic trace minerals. For Mintrex Zn, Cu, and Mn (TRT 7 to 12), there was a linear increase in cumulative gain:feed ratio (P < 0.04), and for Mintrex Zn and Mn, there was a linear increase in cumulative gain (P < 0.03) to increasing Mintrex addition. A 1-slope broken-line model was used to calculate bioavailable Met activity from Mintrex for comparison with actual intake values. Results indicated that HMTBA from Mintrex was fully available as a Met source.


Subject(s)
Animal Feed , Chickens/growth & development , Chickens/metabolism , Methionine/metabolism , Trace Elements/metabolism , Animal Nutritional Physiological Phenomena , Animals , Diet/veterinary , Dietary Supplements , Duodenum/chemistry , Isotope Labeling , Jejunum/chemistry , Liver/chemistry , Male , Muscle, Skeletal/chemistry , Pancreas/chemistry
7.
Poult Sci ; 84(9): 1397-405, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16206561

ABSTRACT

Poultry diets are typically supplemented with DL-2-hydroxy-4(methylthio) butanoic acid (HMTBA, or the hydroxy analog of methionine) or DL-methionine (DLM). Although HMTBA and DLM provide methionine activity, they are structurally distinct molecules with different physiological characteristics until they are converted to L-methionine. The relative rates of intestinal HMTBA vs. DLM absorption have been controversial, and it has been claimed that HMTBA is not fully absorbed. We measured the uptake of HMTBA and DLM in an in vitro everted intestinal slice model. Sections of intestinal slices (jejunum and ileum) were incubated with 0.1 to 50 mM HMTBA that was radiolabeled or DLM that was radiolabeled, and absorption was measured by scintillation counting. The HMTBA uptake was equal to or greater than DLM absorption in each tissue and at every time point with one exception. Furthermore, the rates of HMTBA absorption were always equal to or significantly greater than DLM uptake. In a separate in vivo experiment, absorption of HMTBA and L-methionine was monitored along the entire gastrointestinal (GI) tract. Broilers were fed commercial-type corn-soy diets supplemented with 0.21% HMTBA. Digesta was collected from crop, proventriculus, gizzard, duodenum, jejunum, ileum, large intestine, and cloaca and analyzed for the concentration of free HMTBA and free methionine in each compartment. These studies demonstrated that HMTBA is absorbed completely and along the entire GI tract, especially the upper GI tract. Furthermore, there was a higher concentration of free L-methionine than HMTBA in the digesta from every segment distal to the gizzard.


Subject(s)
Chickens/metabolism , Intestinal Absorption , Methionine/analogs & derivatives , Methionine/pharmacokinetics , Animals , Diet , Ileum/anatomy & histology , Ileum/metabolism , Jejunum/anatomy & histology , Jejunum/metabolism , Kinetics , Methionine/analysis , Glycine max , Zea mays
8.
J Bone Joint Surg Br ; 87(7): 937-9, 2005 Jul.
Article in English | MEDLINE | ID: mdl-15972906

ABSTRACT

In this cross-over study, we evaluated two types of knee brace commonly used in the conservative treatment of osteoarthritis of the medial compartment. Twelve patients confirmed radiologically as having unilateral osteoarthritis of the medial compartment (Larsen grade 2 to grade 4) were studied. Treatment with a simple hinged brace was compared with that using a valgus corrective brace. Knee kinematics, ground reaction forces, pain and function were assessed during walking and the Hospital for Special Surgery scores were also determined. Significant improvements in pain, function, and loading and propulsive forces were seen with the valgus brace. Treatment with a simple brace showed only significant improvements in loading forces. Our findings suggest that although both braces improved confidence and function during gait, the valgus brace showed greater benefit.


Subject(s)
Braces , Osteoarthritis, Knee/therapy , Walking , Aged , Biomechanical Phenomena , Cross-Over Studies , Female , Gait/physiology , Humans , Knee Joint/physiopathology , Male , Middle Aged , Osteoarthritis, Knee/physiopathology , Pain/physiopathology , Treatment Outcome
9.
Poult Sci ; 84(4): 634-43, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15844822

ABSTRACT

This report will review the history of antibiotic growth promoter (AGP) use in the animal industry, concerns about development of antimicrobial resistance, and response in the European Union and United States to these concerns. A brief description of the history of legislation regarding feed use of antimicrobials in Denmark and the experience of animal producers following the 1998 ban will serve to illustrate the consequences on animal performance and health of withdrawing the approval for this use. The biological basis for antibiotic effects on animal growth efficiency will consider effects on intestinal microbiota and effects on the host animal and will use the germ-free animal to illustrate effects of the conventional microflora. The probability that no single compound will replace all of the functions of antimicrobial growth promoters will be considered, and methods to consolidate and analyze the enlarging database will be discussed.


Subject(s)
Animal Feed , Animal Husbandry/methods , Anti-Bacterial Agents/pharmacology , Animal Feed/adverse effects , Animal Husbandry/legislation & jurisprudence , Animal Husbandry/trends , Animals , Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/adverse effects , Bacteria/drug effects , Denmark , Drug Resistance, Bacterial , Drug Utilization/legislation & jurisprudence , Drug Utilization/trends , European Union , United States
10.
Clin Rehabil ; 17(5): 565-71, 2003 Aug.
Article in English | MEDLINE | ID: mdl-12952165

ABSTRACT

OBJECTIVE: To investigate which knee kinematic characteristics show the greatest differences between stroke patients with minimal residual disability and age-matched healthy volunteers as a first step towards the development of a sensitive, objective measure of performance of movement for use in the clinical setting. DESIGN: A comparative study. SETTING: A movement analysis laboratory. SUBJECTS: Ten patients between 6 and 12 months post stroke aged between 65 and 74 years and 10 age-matched healthy volunteers. All patients had made a good recovery and were able to complete all of the functional tasks. INTERVENTIONS: Each subject had reflective markers placed on anatomical landmarks and was filmed performing three movement tasks: sit-to-stand, walking, and step on block. MAIN OUTCOME MEASURES: Knee kinematic characteristics involving timing, joint angle and angular velocity at key points during each task. RESULTS: Significant differences were found between patients and volunteers for only some of the timing and joint angle characteristics but for all angular velocity characteristics for which the mean differences ranged from 31.85 degrees/s for sit-to-stand (p = 0.013) to 82.5 degrees/s (p = 0.014) for the swing phase of gait. CONCLUSIONS: These preliminary findings suggest that angular velocity of the knee during functional tasks might have potential as a sensitive, objective measure of performance of movement after stroke for patients with minimal residual disability.


Subject(s)
Biomechanical Phenomena , Knee , Movement/physiology , Stroke Rehabilitation , Walking , Aged , Case-Control Studies , Humans , Time Factors
11.
Nucleic Acids Res ; 29(12): E59-9, 2001 Jun 15.
Article in English | MEDLINE | ID: mdl-11410682

ABSTRACT

We have constructed new yeast vectors for targeted integration of desired sequences at the Saccharomyces cerevisiae HO locus. Insertion at HO has been shown to have no effect on yeast growth, and thus these integrations should be neutral. One vector contains the KanMX selectable marker, and integrants can be selected by resistance to G418. The other vector contains the hisG-URA3-hisG cassette, and integrants can be selected by uracil prototrophy. Subsequent growth on 5-FOA permits identification of colonies where recombination between the hisG tandem repeats has led to loss of the URA3 marker and return to uracil auxotrophy. We also describe several new bacterial polylinker vectors derived from pUC21 (ampicillin resistance) and pUK21 (kanamycin resistance).


Subject(s)
DNA, Fungal/genetics , Deoxyribonucleases, Type II Site-Specific/metabolism , Genetic Vectors/genetics , Recombination, Genetic/genetics , Saccharomyces cerevisiae/genetics , Ampicillin Resistance , DNA, Bacterial/genetics , DNA, Fungal/metabolism , Drug Resistance, Microbial/genetics , Escherichia coli/genetics , Fungal Proteins/genetics , Genes, Fungal/genetics , Genetic Markers/genetics , Gentamicins/pharmacology , Kanamycin Resistance , Molecular Sequence Data , Orotic Acid/analogs & derivatives , Orotic Acid/pharmacology , Restriction Mapping , Saccharomyces cerevisiae/drug effects , Saccharomyces cerevisiae/enzymology , Saccharomyces cerevisiae/growth & development , Saccharomyces cerevisiae Proteins , Tandem Repeat Sequences/genetics
12.
J Immunol ; 166(6): 3855-64, 2001 Mar 15.
Article in English | MEDLINE | ID: mdl-11238629

ABSTRACT

Signal transduction initiated by B cell Ag receptor (BCR) cross-linking plays an important role in the development and activation of B cells. Therefore, considerable effort has gone into determining the biochemical signaling events initiated by the BCR and delineating which events participate in specific biological responses to Ag. We used two inhibitors of mitogen-activated protein kinase/extracellular signal-regulated kinase kinase (MEK) 1 and MEK2, PD98059, and U0126, to assess the role the Ras-mitogen-activated protein kinase pathway plays in several BCR-induced responses. PD98059 or U0126 treatment substantially inhibited the BCR-induced activation of the extracellular signal-regulated kinase (ERK) forms of mitogen-activated protein kinase in the immature B cell line WEHI-231, in immature splenic B cells, and in mature splenic B cells. However, MEK-ERK inhibition did not block BCR-induced growth arrest or apoptosis of WEHI-231 cells or apoptosis of immature splenic B cells, indicating that the MEK-ERK pathway is not required for these events. In contrast, PD98059 and U0126 treatment did inhibit the up-regulation of specific BCR-induced proteins, including the transcription factor Egr-1 in WEHI-231 and mature splenic B cells, and the CD44 adhesion molecule and CD69 activation marker in mature splenic B cells. Moreover, both inhibitors suppressed BCR-induced proliferation of mature splenic B cells, in the absence and in the presence of IL-4. Therefore, activation of the MEK-ERK pathway is necessary for a subset of B cell responses to Ag.


Subject(s)
Antigens/immunology , B-Lymphocyte Subsets/enzymology , B-Lymphocyte Subsets/immunology , Immediate-Early Proteins , MAP Kinase Kinase Kinases/antagonists & inhibitors , MAP Kinase Signaling System/immunology , Mitogen-Activated Protein Kinases/antagonists & inhibitors , Animals , Antigens, CD/biosynthesis , Antigens, Differentiation, T-Lymphocyte/biosynthesis , Apoptosis/drug effects , Apoptosis/immunology , B-Lymphocyte Subsets/cytology , B-Lymphocyte Subsets/drug effects , Butadienes/pharmacology , Cell Differentiation/drug effects , Cell Differentiation/immunology , Cell Division/drug effects , Cell Division/immunology , Cell Separation , Cells, Cultured , DNA-Binding Proteins/antagonists & inhibitors , DNA-Binding Proteins/biosynthesis , Early Growth Response Protein 1 , Enzyme Activation/drug effects , Enzyme Activation/immunology , Enzyme Inhibitors/pharmacology , Female , Flavonoids/pharmacology , Growth Inhibitors/pharmacology , Hyaluronan Receptors/biosynthesis , Lectins, C-Type , Lymphocyte Activation/drug effects , MAP Kinase Kinase Kinases/metabolism , MAP Kinase Kinase Kinases/physiology , MAP Kinase Signaling System/drug effects , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Inbred DBA , Mitogen-Activated Protein Kinases/metabolism , Mitogen-Activated Protein Kinases/physiology , Nitriles/pharmacology , Receptors, Antigen, B-Cell/antagonists & inhibitors , Receptors, Antigen, B-Cell/physiology , Spleen/cytology , Spleen/immunology , Transcription Factors/antagonists & inhibitors , Transcription Factors/biosynthesis , Tumor Cells, Cultured , Up-Regulation/drug effects , Up-Regulation/immunology
13.
J Biol Chem ; 271(11): 6458-66, 1996 Mar 15.
Article in English | MEDLINE | ID: mdl-8626447

ABSTRACT

B cell antigen receptor (BCR) cross-linking activates both Src family and Syk tyrosine kinases, resulting in increased cellular protein-tyrosine phosphorylation and activation of several downstream signaling enzymes. To define the role of Syk in these events, we expressed the BCR in the AtT20 mouse pituitary cell line. These nonlymphoid cells endogenously expressed the Src family kinase Fyn but not Syk. Anti-IgM stimulation of these cells failed to induce most of the signaling events that occur in B cells. BCR-expressing AtT20 transfectants were generated that also expressed Syk. Syk expression reconstituted several signaling events upon anti-IgM stimulation, including Syk phosphorylation and association with the BCR, tyrosine phosphorylation of numerous proteins including Shc, and activation of mitogen-activated protein kinase. In contrast, Syk expression did not reconstitute anti-IgM-induced inositol phosphate production. A catalytically inactive Syk mutant could associate with the BCR and become tyrosine phosphorylated but could not reconstitute downstream signaling events. Expression of the Src family kinase Lck instead of Syk also did not reconstitute signaling. Thus, wild type Syk was required to reconstitute several BCR-induced signaling events but was not sufficient to couple the BCR to the phosphoinositide signaling pathway.


Subject(s)
Enzyme Precursors/metabolism , Protein-Tyrosine Kinases/metabolism , Receptors, Antigen, B-Cell/metabolism , Amino Acid Sequence , Animals , Antibodies, Anti-Idiotypic/administration & dosage , B-Lymphocytes/immunology , B-Lymphocytes/metabolism , Base Sequence , Calcium-Calmodulin-Dependent Protein Kinases/metabolism , Cell Line , Cloning, Molecular , DNA Primers/genetics , DNA, Complementary/genetics , Enzyme Precursors/genetics , Gene Expression Regulation, Enzymologic , Intracellular Signaling Peptides and Proteins , Mice , Molecular Sequence Data , Phosphatidylinositols/metabolism , Protein-Tyrosine Kinases/genetics , Receptors, Antigen, B-Cell/genetics , Signal Transduction , Syk Kinase , Transfection
14.
Mil Med ; 160(12): 631-5, 1995 Dec.
Article in English | MEDLINE | ID: mdl-8775391

ABSTRACT

This article explores the Operation Desert Shield/Storm performance of soldiers receiving predeployment treatment in the Alcohol and Drug Abuse Prevention and Control Program (ADAPCP). It describes the impact that ADAPCP soldiers' performance has on their units, both from the soldiers' and the leadership's points of view. Examination of the ADAPCP's predeployment and deployment role indicates that the ADAPCP can do more for soldiers who, while attempting to overcome substance abuse problems, face the new challenge of coping with the upheaval of deployment to a war zone. Suggestions are also made for developing an ADAPCP peace-to-war transition plan.


Subject(s)
Alcohol Drinking/prevention & control , Military Medicine , Military Personnel , Substance-Related Disorders/prevention & control , Warfare , Adult , Female , Humans , Male , Saudi Arabia , United States
15.
Ann N Y Acad Sci ; 766: 195-201, 1995 Sep 07.
Article in English | MEDLINE | ID: mdl-7486656

ABSTRACT

The antigen receptor of B lymphocytes (BCR) plays important roles in recognition of foreign antigens and self-components to allow the immune system to make appropriate antibody responses. The BCR is a complex between membrane immunoglobulin and the Ig-alpha and Ig-beta heterodimer. Site-directed mutagenesis experiments have shown that the mu heavy chain transmembrane domain plays a key role in the association of mIgM with Ig-alpha/Ig-beta. In the absence of complex formation, mIgM is retained in the endoplasmic reticulum, and this function is also specified by the mu chain transmembrane domain. The ability of various mutant mIgM molecules to associate with Ig-alpha/Ig-beta correlates well with their ability to induce signal transduction reactions such as protein tyrosine phosphorylation and phosphoinositide breakdown. Thus, the signaling ability of the BCR appears to reside in the Ig-alpha/Ig-beta heterodimer. The cytoplasmic domains of Ig-alpha and Ig-beta each contain an ITAM sequence, which is defined by its limited homology with subunits of the T-cell antigen receptor and of Fc receptors. Moreover, chimeric proteins containing these ITAMs and surrounding sequences from the cytoplasmic domains of Ig-alpha or Ig-beta exhibit signaling function characteristics of the intact BCR. The Ig-alpha and Ig-beta chimeras are each capable of inducing all of the BCR signaling events tested and thus represent redundant functions. Cross-linking these chimeras leads to their phosphorylation and to binding of the intracellular tyrosine kinases Lyn and Syk. The BCR expressed in the nonlymphoid AtT20 cells, which express the Src-family tyrosine kinase Fyn but not Syk, was not able to trigger vigorous signaling reactions. Introduction of the active form of Syk into these cells restored some signaling events. These results are consistent with a model in which the ITAMs act to initiate the BCR signaling reactions by binding and activating tyrosine kinases.


Subject(s)
B-Lymphocytes/immunology , Receptors, Antigen, T-Cell/physiology , Signal Transduction/immunology , Animals , Antigens/immunology , Cell Membrane/immunology , Cell Membrane/physiology , Cytoplasm/immunology , Humans , Macromolecular Substances , Receptors, Antigen, B-Cell/physiology
16.
Leuk Lymphoma ; 15(3-4): 273-9, 1994 Oct.
Article in English | MEDLINE | ID: mdl-7866275

ABSTRACT

We report the complications and outcome of high-dose melphalan and TBI combined with ABMT used in the treatment of multiple myeloma at a single centre. Twenty-three patients, aged 65 years or less, who underwent the procedure are reviewed. All had chemosensitive disease. Response to ABMT assessed at 3 months showed 75% of evaluable patients to have further tumour cytoreduction of at least 50%, with 24% of patients who entered ABMT with residual disease eventually achieving CR. There was one toxic death. The overall survival is 60% and the progression-free survival is 49.8% at a median follow-up time of 17 months. Relapse or disease progression has occurred in 27% of patients, of whom half have died. No significant prognostic factors affecting survival were found although those patients with IgG myeloma had a better outcome. Patients transplanted in first plateau appeared to do significantly better if they had been resistant to their first-line chemotherapy but had then responded to further conventional chemotherapy (p = 0.029).


Subject(s)
Bone Marrow Transplantation , Multiple Myeloma/therapy , Adult , Bone Marrow Transplantation/adverse effects , Combined Modality Therapy , Disease Progression , Dose-Response Relationship, Drug , Female , Humans , Male , Melphalan/therapeutic use , Middle Aged , Multiple Myeloma/drug therapy , Multiple Myeloma/radiotherapy , Treatment Outcome , Whole-Body Irradiation
18.
Clin Oncol (R Coll Radiol) ; 5(6): 378-83, 1993.
Article in English | MEDLINE | ID: mdl-8305360

ABSTRACT

In view of increasing controversy regarding the role of double hemibody irradiation (DHBI) in the treatment of multiple myeloma, we have analysed the use of this technique at our institution over a 6-year period. Fifty-five patients with multiple myeloma were treated with both upper and lower hemibody irradiation between January 1985 and January 1991; 42 had relapsed post-plateau and 13 were chemoresistant to initial therapy. Fifteen patients received alpha IFN-2b maintenance therapy post-DHBI, at a dose of 3 Mu three times per week, as part of a randomized trial. Ninety-five per cent of patients experienced symptomatic improvement in bone pain post-DHBI, 21% of whom discontinued opiate analgesics altogether; 63% had a minor biochemical response and 38% had a partial biochemical response. The overall survival (OS) and progression free survivals (PFS) in all patients were 11 months and 8 months respectively. No significant difference was noted in either OS or PFS, according to whether patients were chemoresistant or had relapsed post-plateau. alpha IFN did not appear to prolong survival (OS or PFS) post-DHBI. Cytopenia was a significant problem, such that only 60% of patients had counts adequate enough to be eligible for alpha IFN. We conclude that DHBI is an effective treatment in patients with relapsed multiple myeloma and in those who are chemoresistant to initial therapy.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Hemibody Irradiation , Multiple Myeloma/radiotherapy , Adult , Aged , Antineoplastic Agents/therapeutic use , Combined Modality Therapy , Erythrocyte Transfusion , Female , Hemibody Irradiation/adverse effects , Humans , Interferon alpha-2 , Interferon-alpha/adverse effects , Interferon-alpha/therapeutic use , Male , Middle Aged , Multiple Myeloma/mortality , Multiple Myeloma/pathology , Neoplasm Staging , Platelet Transfusion , Radiation Pneumonitis/etiology , Radiodermatitis/etiology , Recombinant Proteins , Recurrence , Survival Rate , Treatment Outcome
19.
Appl Opt ; 32(16): 2901-6, 1993 Jun 01.
Article in English | MEDLINE | ID: mdl-20829893

ABSTRACT

Existing experimental configurations to excite surface plasmons are reviewed, and a new experimental method for exciting surface plasmons is described. A transverse magnetic polarized wave is guided by a polarization-preserving optical fiber, collimated by a gradient-index lens, and launched into an optical cell filled with index-matching fluid. The wave is reflected off of a rotating mirror and excites a surface plasmon on a dielectric-metal interface by attenuated total reflection. The reflectance and incidence angles are measured simultaneously with a position-sensitive photodiode. The main advantages of this new method, compared with existing methods, are the low equipment costs and the ease with which a variety of surface-plasmon experiments can be performed.

20.
Leuk Lymphoma ; 8(4-5): 409-13, 1992 Nov.
Article in English | MEDLINE | ID: mdl-1290966

ABSTRACT

We report two cases of acute myelomonocytic leukaemia with abnormal eosinophils (M4Eo) in which the presenting feature was small bowel obstruction. We suggest there is a unique clinicopathological association between small intestine involvement with leukaemia and the M4Eo subtype. Central nervous system involvement by myeloblastoma occurred in one of the two cases which is a recognised feature of M4Eo and should necessitate prophylaxis with intrathecal therapy. Inversion of chromosome 16 which is a cytogenetic marker for M4Eo was demonstrable in one of the two cases.


Subject(s)
Cerebral Cortex/pathology , Chromosome Inversion , Chromosomes, Human, Pair 16/ultrastructure , Duodenal Neoplasms/pathology , Eosinophils/pathology , Jejunal Neoplasms/pathology , Leukemia, Myeloid/pathology , Leukemia, Myelomonocytic, Acute/pathology , Leukemic Infiltration/pathology , Biomarkers, Tumor , Bone Marrow Examination , Diagnosis, Differential , Duodenal Neoplasms/genetics , Female , Humans , Incidence , Intestinal Obstruction/diagnosis , Intestinal Obstruction/etiology , Jejunal Neoplasms/genetics , Leukemia, Myeloid/epidemiology , Leukemia, Myelomonocytic, Acute/classification , Leukemia, Myelomonocytic, Acute/diagnosis , Leukemia, Myelomonocytic, Acute/genetics , Leukemic Infiltration/epidemiology , Leukocyte Count , Male , Middle Aged , Precursor Cell Lymphoblastic Leukemia-Lymphoma/diagnosis , Prognosis
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