102 results match your criteria: "Univ. of Massachusetts[Affiliation]"

Environmental monitoring using sensitive methods for detection and elimination of harborage sites of Listeria monocytogenes is key to the control of this organism. The 3M Petrifilm Environmental Listeria (EL) Plate-a no enrichment method-was compared with the USDA/FSIS, modified USDA/FSIS (mUSDA), and ISO methods for detection/recovery of L. monocytogenes on 4 environmental surfaces (brick, dairy board, stainless steel, and epoxy resin).

View Article and Find Full Text PDF

Improvement of stability of oil-in-water emulsions containing caseinate-coated droplets by addition of sodium alginate.

J Food Sci

November 2007

Biopolymers and Colloids Research Laboratory, Dept. of Food Science, Univ. of Massachusetts, Amherst, MA 01003, USA.

The potential of sodium alginate for improving the stability of emulsions containing caseinate-coated droplets was investigated. One wt% corn oil-in-water emulsions containing anionic caseinate-coated droplets (0.15 wt% sodium caseinate) and anionic sodium alginate (0 to 1 wt%) were prepared at pH 7.

View Article and Find Full Text PDF

The impact of sodium nitrite (NaNO2) on detection and recovery of Listeria monocytogenes from select ready-to-eat (RTE) foods including smoked salmon, smoked ham, beef frankfurters, and beef bologna was assessed. Nitrite-containing (NC; 100 to 200 ppm NaNO2) or nitrite-free (NF) foods were inoculated with a 5-strain cocktail of L. monocytogenes by immersion into Butterfield's buffer solution containing 5.

View Article and Find Full Text PDF

Conjugated linoleic acid (CLA) has been shown to reduce body fat and increase lean body mass in mice, rats, and pigs. A recent human trial indicated that CLA may work more effectively if used for prevention of body fat deposition and weight gain. To test this hypothesis, we conducted 2 experiments using relatively old mice (older than 6 mo): experiment 1, supplementation of CLA during dietary restriction and experiment 2, supplementation during ad libitum feeding followed by restriction.

View Article and Find Full Text PDF

There is a pressing need for edible delivery systems to encapsulate, protect, and release bioactive lipids within the food, medical, and pharmaceutical industries. The fact that these delivery systems must be edible puts constraints on the type of ingredients and processing operations that can be used to create them. Emulsion technology is particularly suited for the design and fabrication of delivery systems for encapsulating bioactive lipids.

View Article and Find Full Text PDF

Age-related resistance to skeletal muscle fatigue is preserved during ischemia.

J Appl Physiol (1985)

November 2007

Dept. of Kinesiology, Univ. of Massachusetts, 108 Totman Bldg., 30 Eastman Lane, Amherst, MA 01003, USA.

During voluntary contractions, the skeletal muscle of healthy older adults often fatigues less than that of young adults, a result that has been explained by relatively greater reliance on muscle oxidative metabolism in the elderly. Our aim was to investigate whether this age-related fatigue resistance was eliminated when oxidative metabolism was minimized via ischemia induced by cuff (220 mmHg). We hypothesized that 1) older men (n = 12) would fatigue less than young men (n = 12) during free-flow (FF) contractions; 2) both groups would fatigue similarly during ischemia; and 3) reperfusion would reestablish the fatigue resistance of the old.

View Article and Find Full Text PDF

Endothelin-1 (ET) induces increases in intracellular Ca(2+) concentration ([Ca(2+)](i)), Ca(2+) sensitization, and contraction of both bronchiole and pulmonary arteriole smooth muscle cells (SMCs) and may play an important role in the pathophysiology of asthma and pulmonary hypertension. However, because it remains unclear how changes in [Ca(2+)](i) and the Ca(2+) sensitivity regulate SMC contraction, we have studied mouse lung slices with phase-contrast and confocal microscopy to correlate the ET-induced contraction with the changes in [Ca(2+)](i) and Ca(2+) sensitivity of bronchiole and arteriole SMCs. In comparison with acetylcholine (ACh) or serotonin (5-HT), ET induced a stronger and long-lasting contraction of both bronchioles and arterioles.

View Article and Find Full Text PDF

ATP-dependent sugar transport complexity in human erythrocytes.

Am J Physiol Cell Physiol

February 2007

Dept. of Biochemistry and Molecular Pharmacology, Univ. of Massachusetts Medical School, 364 Plantation St., Worcester, MA 01605, USA.

Human erythrocyte glucose sugar transport was examined in resealed red cell ghosts under equilibrium exchange conditions ([sugar](intracellular) = [sugar](extracellular), where brackets indicate concentration). Exchange 3-O-methylglucose (3MG) import and export are monophasic in the absence of cytoplasmic ATP but are biphasic when ATP is present. Biphasic exchange is observed as the rapid filling of a large compartment (66% cell volume) followed by the slow filling of the remaining cytoplasmic space.

View Article and Find Full Text PDF

Considerable attention has focused on the role of protein kinase C (PKC) in triggering the profound infarct-sparing effect of ischemic preconditioning (PC). In contrast, the involvement of inositol 1,4,5-trisphosphate [Ins(1,4,5)P(3)], the second messenger generated in parallel with the diacylglycerol-PKC pathway, remains poorly understood. We hypothesized that, if Ins(1,4,5)P(3) signaling [i.

View Article and Find Full Text PDF

Doublet discharges in motoneurons of young and older adults.

J Neurophysiol

May 2006

Department of Exercise Science, Univ. of Massachusetts at Amherst, Totman Bldg., Amherst, MA 01003-9258, USA.

The purpose of this study was to investigate the occurrence of motor unit doublet discharges in young and older individuals at different rates of increasing force. Participants included eight young (21.9 +/- 3.

View Article and Find Full Text PDF

Prophylactic treatment with D-myo-inositol 1,4,5-trisphosphate hexasodium [D-myo-Ins(1,4,5)P3], the sodium salt of the endogenous second messenger Ins(1,4,5)P3, triggers a reduction of infarct size comparable in magnitude to that seen with ischemic preconditioning (PC). However, the mechanisms underlying D-myo-Ins(1,4,5)P3-induced protection are unknown. Accordingly, our aim was to investigate the role of four archetypal mediators implicated in PC and other cardioprotective strategies (i.

View Article and Find Full Text PDF

Contractile effects of adenosine A1 and A2A receptors in isolated murine hearts.

Am J Physiol Heart Circ Physiol

January 2006

Dept. of Physiology, Univ. of Massachusetts Medical School, 55 Lake Ave. N., Worcester, MA 01655, USA.

The adenosine A1 receptor (A1R) inhibits beta-adrenergic-induced contractile effects (antiadrenergic action), and the adenosine A2A receptor (A2AR) both opposes the A1R action and enhances contractility in the heart. This study investigated the A1R and A2AR function in beta-adrenergic-stimulated, isolated wild-type and A2AR knockout murine hearts. Constant flow and pressure perfused preparations were employed, and the maximal rate of left ventricular pressure (LVP) development (+dp/dt(max)) was used as an index of cardiac function.

View Article and Find Full Text PDF

The purpose of this study was to determine if gender differences exist in the variability of various lower extremity (LE) segment and joint couplings during an unanticipated cutting maneuver. 3-D kinematics were collected on 24 college soccer players (12 M, 12 F) while each performed the cutting maneuver. The following intralimb couplings were studied: thigh rotation (rot)/leg rot; thigh abduction-adduction/leg abd-add; hip abd-add/knee rot; hip rot/knee abd-add; knee flexion-extension/knee rot; knee flx-ext/hip rot.

View Article and Find Full Text PDF

Age-related changes in ATP-producing pathways in human skeletal muscle in vivo.

J Appl Physiol (1985)

November 2005

Dept. of Exercise Science, Totman 108, Univ. of Massachusetts, Amherst, MA 01003, USA.

Energy for muscle contractions is supplied by ATP generated from 1) the net hydrolysis of phosphocreatine (PCr) through the creatine kinase reaction, 2) oxidative phosphorylation, and 3) anaerobic glycolysis. The effect of old age on these pathways is unclear. The purpose of this study was to examine whether age may affect ATP synthesis rates from these pathways during maximal voluntary isometric contractions (MVIC).

View Article and Find Full Text PDF

Influence of Cosolvent Systems on the Gelation Mechanism of Globular Protein: Thermodynamic, Kinetic, and Structural Aspects of Globular Protein Gelation.

Compr Rev Food Sci Food Saf

July 2005

Authors Baier and McClements are with Biopolymer and Colloids Research Laboratory, Dept. of Food Science, Univ. of Massachusetts, Amherst, MA 01003.

How thermostability and gelation of globular protein are affected by cosolvent systems present in food systems is critical to understanding their functionality. The expression of these functional attributes depends on the molecular structure and thermal-mechanical history of the protein, as well as its chemical environment. To improve the design of processing protein-containing food systems, one must fully understand the thermodynamic, kinetic, and structural impact of cosolvent on globular protein gelation.

View Article and Find Full Text PDF

The alpha-actinin 3 (ACTN3) gene encodes a protein of the Z disk of myofibers, and a polymorphism of ACTN3 results in complete loss of the protein. The ACTN3 genotype (R577X) has been found to be associated with performance in Australian elite athletes (Yang N, MacArthur DG, Gulbin JP, Hahn AG, Beggs AH, Easteal S, and North K. Am J Hum Genet 73: 627-631, 2003).

View Article and Find Full Text PDF

The mitochondrial membrane potential (DeltaPsi(m)) underlies many mitochondrial functions, including Ca(2+) influx into the mitochondria, which allows them to serve as buffers of intracellular Ca(2+). Spontaneous depolarizations of DeltaPsi(m), flickers, have been observed in isolated mitochondria and intact cells using the fluorescent cationic lipophile tetramethylrhodamine ethyl ester (TMRE), which distributes across the inner mitochondrial membrane in accordance with the Nernst equation. Flickers in cardiomyocytes have been attributed to uptake of Ca(2+) released from the sarcoplasmic reticulum (SR) via ryanodine receptors in focal transients called Ca(2+) sparks.

View Article and Find Full Text PDF

Neurotensin (NT), a hormone released from intestine by ingested fat, facilitates lipid digestion by stimulating pancreatic secretion and slowing the movement of chyme. In addition, NT can contract the gall bladder and enhance the enterohepatic circulation (EHC) of bile acids to promote micelle formation. Our recent finding that NT enhanced and an NT antagonist inhibited [(3)H]taurocholate ([(3)H]TC) absorption from proximal rat small intestine indicated a role for endogenous NT in the regulation of EHC.

View Article and Find Full Text PDF

Period gene expression in mouse endocrine tissues.

Am J Physiol Regul Integr Comp Physiol

September 2003

Dept. of Biology, Program in Neuroscience, and Center for Neuroendocrine Studies, Univ. of Massachusetts, Amherst, MA 01003, USA.

Circadian rhythms are generated by the oscillating expression of the Per1 and Per2 genes, which are expressed not only in the central brain pacemaker but also in peripheral tissues. Hormones are likely to coordinate physiological function in time. We performed in situ hybridization to localize mPer1 and mPer2 mRNA to particular cell types and tissue compartments in adrenal, thyroid, and testis.

View Article and Find Full Text PDF

Sorption and desorption of naphthalene by soil organic matter: importance of aromatic and aliphatic components.

J Environ Qual

April 2003

Department of Plant and Soil Sciences, Univ. of Massachusetts, Stockbridge Hall, Amherst, MA 01003-7245, USA.

Nonlinear isotherm behavior has been reported for the sorption of hydrophobic organic compounds (HOCs) in soil organic matter (SOM), but the exact mechanisms are unknown. Our objective was to provide insight into the sorption mechanism of HOCs in SOM by studying the sorption-desorption processes of naphthalene in a mineral soil, its humic fractions, and lignin. Additionally, humin and lignin were used for studying the effects of temperature and cosolvent on HOC sorption.

View Article and Find Full Text PDF

Earth-Based Observations of the Galileo Probe Entry Site.

Science

May 1996

G. Orton, J. Friedson, T. Martin, P. Yanamandra-Fisher, Mail Stop 169-237, Jet Propulsion Laboratory (JPL), California Institute of Technology, Pasadena, CA 91109; J. L. Ortiz, Mail Stop 169-237, JPL, and Instituto de Astrofisica de Andalucia, CSIC, P.O. Box 3004, 18080 Granada, Spain; K. Baines, Mail Stop 183-601, JPL; G. Bjoraker, D. Deming, D. Jennings, G. McCabe, P. Sada, Code 693, NASA Goddard Space Flight Center, Greenbelt, MD 20771; U. Carsenty, DLR Institute for Planetary Exploration, Rudower Chaussee 5, D-12489 Berlin, Germany; F. Colas, Bureau des Longitudes, 75015 Paris, France; A. Dayal and W. Hoffmann, Stewart Observatory, Univ. of Arizona, Tucson, AZ 85721; P. Drossart and J. Lecacheux, DESPA, Observatoire de Paris-Meudon, 92195 Meudon Cedex, France; E. Frappa and P. Laques, Observatoire Midi-Pyrenees, 65200 Bagneres de Bigorre, France; J. Goguen, Mail Stop 183-501, JPL; W. Golisch, D. Griep, C. Kaminski, J. Hora, Institute for Astronomy, Univ. of Hawaii, Honolulu, HI 96822; C. Hernandez, 9430 S.W. 29 Terrace, Miami, FL 33165; J. Kuhn, H. Lin, J. Varsik, National Solar Observatory, Sunspot, NM 88349; S. Limaye, Space Science and Engineering Center, Univ. of Wisconsin, Madison, WI 53706; T. Momary, 3806 Geology Building, Univ. of California, Los Angeles, CA 90024-1567; D. Parker, 12911 Lerida Street, Coral Gables, FL 33156; R. Puetter, CASS, Univ. of California at San Diego, La Jolla, CA 92093-0111; M. Ressler, Mail Stop 169-506, JPL; G. Reyes, Mail Stop 300-329, JPL; J. Spencer, Lowell Observatory, 1400 Mars Hill Road, Flagstaff, AZ 86001; J. Spitale and S. Stewart, Division of Geological and Planetary Sciences, 170-20, California Institute of Technology, Pasadena, CA 91125; J. Warell, Uppsala Astronomical Observatory, Box 515, S-75120 Uppsala, Sweden; W. Wild, Department of Astronomy and Astrophysics, Univ. of Chicago, Chicago, IL 60637; G. Fazio, Smithsonian Astrophysical Observatory, Cambridge, MA 02138; L. Deutsch, Five College Astronomy Department, Univ. of Massachusetts, Amherst, MA 01003.

Earth-based observations of Jupiter indicate that the Galileo probe probably entered Jupiter's atmosphere just inside a region that has less cloud cover and drier conditions than more than 99 percent of the rest of the planet. The visual appearance of the clouds at the site was generally dark at longer wavelengths. The tropospheric and stratospheric temperature fields have a strong longitudinal wave structure that is expected to manifest itself in the vertical temperature profile.

View Article and Find Full Text PDF

Appearance of increased proportions of monocytes bearing the 72kd(FcRI) receptor for IgG correlated to aberrant monocyte (MO) functions, depressed immune functions, and poor clinical outcome. The trauma patients' FcRI+ MO subpopulation produced the majority of their elevated IL-6, TNF alpha, TGF beta, and PGE2. IgG stimulation of patients' MO through FcRI not only stimulated TNF alpha, IL-6, and PGE2 levels, but also greatly augmented the levels of these monokines produced after subsequent bacterial challenge.

View Article and Find Full Text PDF