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1.
Biosens Bioelectron ; 130: 245-253, 2019 Apr 01.
Article in English | MEDLINE | ID: mdl-30769289

ABSTRACT

Detailed knowledge regarding sensor based technologies for the detection of food contamination often remains concealed within scientific journals or divided between numerous commercial kits which prevents optimal connectivity between companies and end-users. To overcome this barrier The End user Sensor Tree (TEST) has been developed. TEST is a comprehensive, interactive platform including over 900 sensor based methods, retrieved from the scientific literature and commercial market, for aquatic-toxins, mycotoxins, pesticides and microorganism detection. Key analytical parameters are recorded in excel files while a novel classification system is used which provides, tailor-made, experts' feedback using an online decision tree and database introduced here. Additionally, a critical comparison of reviewed sensors is presented alongside a global perspective on research pioneers and commercially available products. The lack of commercial uptake of the academically popular electrochemical and nanomaterial based sensors, as well as multiplexing platforms became very apparent and reasons for this anomaly are discussed.


Subject(s)
Biosensing Techniques/methods , Food Contamination/analysis , Mycotoxins/isolation & purification , Pesticides/isolation & purification , Biosensing Techniques/classification , Databases, Factual , Humans , Mycotoxins/chemistry , Nanostructures/chemistry , Pesticides/chemistry
2.
J Mol Cell Cardiol ; 60: 151-60, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23632046

ABSTRACT

Nebulette (NEBL) is a sarcomeric Z-disk protein involved in mechanosensing and force generation via its interaction with actin and tropomyosin-troponin complex. Genetic abnormalities in NEBL lead to dilated cardiomyopathy (DCM) in humans and animal models. The objectives of this study are to determine the earliest preclinical mechanical changes in the myocardium and define underlying molecular mechanisms by which NEBL mutations lead to cardiac dysfunction. We examined cardiac function in 3-month-old non-transgenic (non-Tg) and transgenic (Tg) mice (WT-Tg, G202R-Tg, A592E-Tg) by cardiac magnetic resonance (CMR) imaging. Contractility and calcium transients were measured in isolated cardiomyocytes. A592E-Tg mice exhibited enhanced in vivo twist and untwisting rate compared to control groups. Ex vivo analysis of A592E-Tg cardiomyocytes showed blunted calcium decay response to isoproterenol. CMR imaging of G202R-Tg mice demonstrated reduced torsion compared to non-Tg and WT-Tg, but conserved twist and untwisting rate after correcting for geometric changes. Ex vivo analysis of G202R-Tg cardiomyocytes showed elevated calcium decay at baseline and a conserved contractile response to isoproterenol stress. Protein analysis showed decreased α-actinin and connexin43, and increased cardiac troponin I phosphorylation at baseline in G202R-Tg, providing a molecular mechanism for enhanced ex vivo calcium decay. Ultrastructurally, G202R-Tg cardiomyocytes exhibited increased I-band and sarcomere length, desmosomal separation, and enlarged t-tubules. A592E-Tg cardiomyocytes also showed abnormal ultrastructural changes and desmin downregulation. This study showed distinct effects of NEBL mutations on sarcomere ultrastructure, cellular contractile function, and calcium homeostasis in preclinical DCM in vivo. We suggest that these abnormalities correlate with detectable myocardial wall motion patterns.


Subject(s)
Calcium Signaling , Cardiomegaly/metabolism , Cytoskeletal Proteins/metabolism , Heart Defects, Congenital/metabolism , LIM Domain Proteins/metabolism , Mutation , Myocardium/metabolism , Myocytes, Cardiac/metabolism , Actinin/genetics , Actinin/metabolism , Animals , Cardiomegaly/genetics , Cardiomegaly/pathology , Cytoskeletal Proteins/genetics , Heart Defects, Congenital/genetics , Heart Defects, Congenital/pathology , LIM Domain Proteins/genetics , Mice , Mice, Transgenic , Myocardial Contraction/genetics , Myocardium/pathology , Myocytes, Cardiac/pathology , Sarcomeres/genetics , Sarcomeres/metabolism , Sarcomeres/pathology
3.
Mini Rev Med Chem ; 12(11): 1063-70, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22924484

ABSTRACT

Herein we discuss the effects of hormones on reproduction, but with a focus on the ripples that emanate from the main effects. That is, the role of hormones in reproductive events is both well-known and well accepted; less studied and understood are effects that appear to be ancillary to the primary objectives of the hormonal effects, which support, complement and extend their primary effects. We present evidence for how the hormonal stimulation of pregnancy constructs the maternal brain; makes it more efficient; enhances cognition; regulates stress responsiveness; modifies sensory systems (we discuss mainly olfaction); neurogenesis; and learning. Thus, steroid and other hormones and neuropeptides restructure the nervous system, particularly of females, to produce and regulate maternal behavior as well as behaviors and physiological systems that contribute to and support what is arguably the primary function of the hormones: survival and effective nurturance of the female's metabolic and genetic investment.


Subject(s)
Brain/physiology , Gonadal Steroid Hormones/metabolism , Reproduction , Animals , Brain/metabolism , Female , Humans , Learning , Neurogenesis , Olfactory Perception , Pregnancy , Stress, Physiological
4.
J Int Med Res ; 39(5): 1824-33, 2011.
Article in English | MEDLINE | ID: mdl-22117983

ABSTRACT

This placebo-controlled, randomized, crossover clinical study examined the effect of chronic wheat dextrin intake on calcium and magnesium absorption. Forty premenopausal and post menopausal women (mean ± SD age 49.9 ± 9.8 years) consumed wheat dextrin or placebo (15 g/day) for 2 weeks prior to (45)calcium ((45)Ca) and (26)magnesium ((26)Mg) absorption testing. After a standardized breakfast, serial blood and urine samples were obtained. The mean ± SD area under the curve from 0 to 9 h for (45)Ca specific activity was 0.81 ± 0.21 for wheat dextrin and 0.82 ± 0.22 for placebo, showing that wheat dextrin had no effect on calcium absorption. The mean ± SD percentage excess of (26)Mg/(24)Mg was 7.8% ± 2.1% for wheat dextrin and 7.9% ± 2.6% for placebo, showing that wheat dextrin had no effect on magnesium absorption. In conclusion, chronic wheat dextrin consumption did not inhibit calcium or magnesium absorption from the gastrointestinal tract in women.


Subject(s)
Calcium/metabolism , Dextrins/administration & dosage , Dietary Supplements , Magnesium/metabolism , Plant Extracts/administration & dosage , Absorption , Adult , Calcium/blood , Cross-Over Studies , Female , Gastrointestinal Tract/drug effects , Gastrointestinal Tract/metabolism , Humans , Magnesium/urine , Middle Aged , Postmenopause , Premenopause , Triticum/chemistry , Vitamin D/blood
5.
J Digit Imaging ; 24(6): 1031-43, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21479733

ABSTRACT

The use and benefits of a multimodality approach in the context of breast cancer imaging are discussed. Fusion techniques that allow multiple images to be viewed simultaneously are discussed. Many of these fusion techniques rely on the use of color tables. A genetic algorithm that generates color tables that have desired properties such as satisfying the order principle, the rows, and columns principle, have perceivable uniformity and have maximum contrast is introduced. The generated 2D color tables can be used for displaying fused datasets. The advantage the proposed method has over other techniques is the ability to consider a much larger set of possible color tables, ensuring that the best one is found. We asked radiologists to perform a set of tasks reading fused PET/MRI breast images obtained using eight different fusion techniques. This preliminary study clearly demonstrates the need and benefit of a joint display by estimating the inaccuracies incurred when using a side-by-side display. The study suggests that the color tables generated by the genetic algorithm are good choices for fusing MR and PET images. It is interesting to note that popular techniques such as the Fire/Gray and techniques based on the HSV color space, which are prevalent in the literature and clinical practice, appear to give poorer performance.


Subject(s)
Algorithms , Breast Neoplasms/diagnosis , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Positron-Emission Tomography/methods , Breast Neoplasms/diagnostic imaging , Color , Female , Finite Element Analysis , Humans , Software
6.
Arch Oral Biol ; 55(9): 663-9, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20580345

ABSTRACT

OBJECTIVE: This study investigated the role of occlusion in the development of biomechanical properties of alveolar bone in the miniature pig, Sus scrofa. The hypothesis tested was that the tissues supporting an occluding tooth would show greater stiffness and less strain than that of a non-occluding tooth. DESIGN: Maxillary teeth opposing the erupting lower first molar (M(1)) were extracted on one side. Occlusion developed on the contralateral side. Serially administered fluorochrome labels tracked bone mineralisation apposition rate (MAR). A terminal experiment measured in vivo buccal alveolar bone strain on occluding and non-occluding sides during mastication. Ex vivo alveolar strains during occlusal loading were subsequently measured using a materials testing machine (MTS/Sintech). Whole specimen stiffness and principal strains were calculated. RESULTS: MAR tended to be higher on the extraction side during occlusion. In vivo buccal shear strains were higher in the alveolar bone of the occluding side vs. the extraction side (mean of 471 microvarepsilon vs. 281 microvarepsilon, respectively; p=0.04); however, ex vivo shear strains showed no significant differences between sides. Stiffness differed between extraction and occlusion side specimens, significantly so in the low load range (344 vs. 668 MPa, respectively; p=0.04). CONCLUSIONS: Greater in vivo shear strains may indicate more forceful chews on the occluding side, whereas the similarity in ex vivo bone strain magnitude suggests a similarity in alveolar bone structure and occlusal load transmission regardless of occlusal status. The big overall change in specimen stiffness that was observed was likely attributable to differences in the periodontal ligament rather than alveolar bone.


Subject(s)
Alveolar Process/physiology , Dental Occlusion , Tooth Extraction , Animals , Biomechanical Phenomena , Compressive Strength , Dental Stress Analysis , Electromyography , Masseter Muscle/growth & development , Mastication/physiology , Maxilla/surgery , Periodontal Ligament/physiology , Shear Strength , Swine , Swine, Miniature , Tooth Calcification/physiology
7.
Orthod Craniofac Res ; 13(2): 106-13, 2010 May.
Article in English | MEDLINE | ID: mdl-20477970

ABSTRACT

OBJECTIVES: The purpose of this study was to investigate the effects of reduced masticatory function on midline suture growth and morphology in growing pigs. SETTING AND SAMPLE POPULATION: The sample was 20 pigs separated into two dietary groups and raised at the Department of Anthropology, Harvard University. Midline suture specimens were analyzed at the Department of Orthodontics, University of Washington. MATERIALS AND METHODS: Ten farm pigs and 10 minipigs, all male, were randomly assigned to hard (n = 9) and soft-diet (n = 11) groups. Fluorochromic mineral labels were administered to document bone apposition, and the animals were killed after 12 weeks. Undecalcified sections of the interfrontal, interparietal, internasal, and intermaxillary sutures were evaluated for bone quantity and sutural thickness, interdigitation ratio and growth rate. RESULTS: Soft-diet pigs were characterized by a slower rate of weight gain and less bone than their hard-diet counterparts. Even after correction for weight gain, soft-diet pigs had reduced suture growth rate and thickness. However, no difference in interdigitation ratio was detected between dietary groups. CONCLUSIONS: Restriction to a soft diet reduces midline suture growth and bone apposition in the growing pig.


Subject(s)
Cranial Sutures/growth & development , Diet , Mastication/physiology , Animal Feed , Animals , Bone Density , Linear Models , Male , Models, Animal , Osteogenesis/physiology , Random Allocation , Sus scrofa , Swine , Swine, Miniature
8.
J Biomech ; 42(12): 1961-6, 2009 Aug 25.
Article in English | MEDLINE | ID: mdl-19501361

ABSTRACT

Alveolar bone supports teeth during chewing through a ligamentous interface with tooth roots. Although tooth loads are presumed to direct the development and adaptation of these tissues, strain distribution in the alveolar bone at different stages of tooth eruption and periodontal development is unknown. This study investigates the biomechanical effects of tooth loading on developing alveolar bone as a tooth erupts into occlusion. Mandibular segments from miniature pigs, Sus scrofa, containing M(1) either erupting or in functional occlusion, were loaded in compression. Simultaneous recordings were made from rosette strain gages affixed to the lingual alveolar bone and the M(2) crypt. Overall, specimens with erupting M(1)s were more deformable than specimens with occluding M(1)s (mean stiffness of 246 vs. 944 MPa, respectively, p=0.004). The major difference in alveolar strain between the two stages was in orientation. The vertically applied compressive loads were more directly reflected in the alveolar bone strains of erupting M(1)s, than those of occluding M(1)s, presumably because of the mediation of a more mature periodontal ligament (PDL) in the latter. The PDL interface between occluding teeth and alveolar bone is likely to stiffen the system, allowing transmission of occlusal loads. Alveolar strains may provide a stimulus for bone growth in the alveolar process and crest.


Subject(s)
Alveolar Process/physiology , Tooth Eruption/physiology , Alveolar Process/growth & development , Animals , Biomechanical Phenomena , Bone Development , Mandible , Stress, Mechanical , Swine
9.
J Food Sci ; 72(9): R152-8, 2007 Nov.
Article in English | MEDLINE | ID: mdl-18034744

ABSTRACT

Despite more than 20 y of awareness of the importance of calcium to health, U.S. calcium intakes remain suboptimal. Fortification of foods with shortfall nutrients is probably the optimal strategy for dealing with widespread nutrient deficiencies, as it has the best chance of reaching the population segments most at risk, as contrasted with attempts at changing individuals' food choices or relying on voluntary supplement taking. Given the wide array of potential calcium fortificants and fortification levels, there is not much to guide manufacturers interested in improving the nutritional value of their products. In this review, we assemble the calcium salts/complexes that have been used or proposed for use as fortificants and describe certain of their measured characteristics that relate to incorporation into foods, particularly what is known of their absorbability. The calcium salts most commonly used as supplements or fortificants exhibit similar absorbability when tested in pure chemical form. Choice of salt will depend mainly upon cost, compatability with the manufacturing process, and consumer acceptability. However, interaction with food, tablet, or beverage matrices can degrade intrinsic absorbability substantially. As a consequence, each product must be explicitly tested to establish the degree to which its calcium is available to consumers.


Subject(s)
Calcium Compounds/therapeutic use , Calcium, Dietary , Dietary Supplements , Food, Fortified , Nutritional Status/drug effects , Biological Availability , Humans , Nutrition Policy , United States
10.
Clin Exp Allergy ; 37(6): 808-22, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17517094

ABSTRACT

The aim of this systematic review was to evaluate the efficacy of amino acid-based formulas (AAF) in patients with cow's milk allergy (CMA). Studies were identified using electronic databases and bibliography searches. Subjects eligible for inclusion were patients of any age with CMA or symptoms suggestive of it. Comparisons of interest were AAF vs. extensively hydrolysed formula (eHF), AAF vs. soy-based formula (SF) and AAF vs. cow's milk or cow's milk-based formula. Outcomes of interest were gastrointestinal (GI), dermatological, respiratory and behavioural symptoms as well as growth. A total of 20 studies [three head-to-head randomized controlled trials (RCTs), three cross-over challenge RCTs, seven clinical trials (CTs) and seven case reports (CRs)] were included in the review. In infants with confirmed or suspected CMA, the use of an AAF was shown to be safe and efficacious. Findings from RCT comparisons of AAF with eHF showed that both formulas are equally efficacious at relieving the symptoms of CMA in confirmed or suspected cases. However, infants in specific subgroups (e.g. non-IgE mediated food-induced gastro-enterocolitis-proctitis syndromes with failure to thrive, severe atopic eczema, or with symptoms during exclusive breastfeeding) were more likely overall to benefit from AAF, as intolerance to eHF may occur. In such cases, symptoms persisting despite eHF feeding usually remit on AAF, and catch-up growth may be seen. Meta-analysis of the findings was not possible due to lack of homogenous reporting of outcomes in the original trials. This systematic review shows clinical benefit from use of AAF in both symptoms and growth in infants and children with CMA who fail to tolerate eHF. Further studies are required to determine the relative medical or economic value of initial treatment with AAF in infants at high risk of eHF intolerance.


Subject(s)
Amino Acids , Infant Food , Infant Formula , Milk Hypersensitivity , Milk, Human , Milk , Soy Milk , Amino Acids/adverse effects , Animals , Breast Feeding/adverse effects , Cattle , Cross-Over Studies , Databases, Factual , Dermatitis, Atopic/diet therapy , Dermatitis, Atopic/immunology , Dermatitis, Atopic/pathology , Enteritis/diet therapy , Enteritis/immunology , Enteritis/pathology , Failure to Thrive/diet therapy , Failure to Thrive/immunology , Failure to Thrive/pathology , Humans , Immunoglobulin E/immunology , Infant , Infant Food/adverse effects , Infant, Newborn , Meta-Analysis as Topic , Milk/adverse effects , Milk Hypersensitivity/diet therapy , Milk Hypersensitivity/immunology , Milk Hypersensitivity/pathology , Proctitis/diet therapy , Proctitis/immunology , Proctitis/pathology , Randomized Controlled Trials as Topic
11.
Arch Oral Biol ; 50(5): 497-506, 2005 May.
Article in English | MEDLINE | ID: mdl-15777531

ABSTRACT

Few studies of distraction osteogenesis in the craniofacial region have examined the dynamic nature of the bone healing process. This study investigated bone formation in distraction sites at various times following slow, moderate, and rapid rates of mandibular distraction in adult rats. After a 3-day latency period, 16 groups of 8-9 rats underwent unilateral mandibular distraction for 5 days at four different rates (0, 0.2, 0.4, and 0.6 mm/day) and were sacrificed at four different time points (6, 10, 24, and 38 days). Vital bone labels were injected prior to sacrifice and histological sections were examined under epifluorescence to measure mineral apposition rate (MAR) and the number of red and green pixels that corresponded to the wavelengths of the two bone labels. These pixel counts were designed to quantify the amount of fluorescent bone formation. For MAR and the pixel counts, no significant differences were found between the distraction rate groups. Over time, MAR was significantly higher (p < 0.001) at 24 days (4.50 microm/day) compared to 38 days (3.78 microm/day). Thus, MAR appears to be elevated at mid-consolidation compared to late consolidation. The pixel counts showed that the 6-day (mid-distraction) and 10-day (early consolidation) time points had significantly lower total fluorescent activity compared to the 24-day (mid-consolidation) and 38-day (late consolidation) time points (p < 0.001). The red, green, and red + green pixel counts were found to correlate significantly but weakly with microdensity (r = 0.318, 0.307, and 0.334, respectively). The pixel counts and microdensity both showed similar patterns over time.


Subject(s)
Bone Regeneration , Mandible/surgery , Osteogenesis, Distraction , Animals , Male , Mandible/physiology , Osteogenesis, Distraction/methods , Postoperative Period , Rats , Rats, Sprague-Dawley , Time Factors
12.
J Hum Evol ; 43(5): 645-57, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12457853

ABSTRACT

In this study we use molar microwear analyses to examine the trophic distinctions among various taxa of Malagasy subfossil lemurs. High resolution casts of the teeth of Megaladapis, Archaeolemur, Palaeopropithecus, Babakotia, and Hadropithecus were examined under a scanning electron microscope. Megaladapis was undoubtedly a browsing folivore, but there are significant differences between species of this genus. However, dietary specialists appear to be the exception; for example, Palaeopropithecus and Babakotia probably supplemented their leaf-eating with substantial amounts of seed-predation, much like modern indrids. Hadropithecus was decidedly not like the modern gelada baboon, but probably did feed on hard objects. Evidence from microwear and coprolites suggests that Archaeolemur probably had an eclectic diet that differed regionally and perhaps seasonally. Substantial trophic diversity within Madgascar's primate community was diminished by the late Quaternary extinctions of the large-bodied species (>9 kg).


Subject(s)
Diet , Lemur/anatomy & histology , Molar/anatomy & histology , Adaptation, Physiological , Animals , Biological Evolution , Dental Enamel/anatomy & histology , Dental Enamel/pathology , Fossils , Lemur/physiology , Molar/pathology
13.
Article in English | MEDLINE | ID: mdl-11733178

ABSTRACT

Among non-mammalian vertebrates, rigid skulls with tight sutural junctions are associated with high levels of cranial loading. The rigid skulls of mammals presumably act to resist the stresses of mastication. The pig, Sus scrofa, is a generalized ungulate with a diet rich in resistant foods. This report synthesizes previous work using strain gages bonded to the bones and sutures of the braincase, zygomatic arch, jaw joint, and mandible with new studies on the maxilla. Strains were recorded during unrestrained mastication and/or in anesthetized pigs during muscle stimulation. Bone strains were 100-1000 micro epsilon, except in the braincase, but sutural strains were higher, regardless of region. Strain regimes were specific to different regions, indicating that theoretical treatment of the skull as a unitary structure is probably incorrect. Muscle contraction, especially the masseter, caused strain patterns by four mechanisms: (1) direct loading of muscle attachment areas; (2) a compressive reaction force at the jaw joint; (3) bite force loading on the snout and mandible; and (4) movement causing new points of contact between mandible and cranium. Some expected patterns of loading were not seen. Most notably, strains did not differ for right and left chewing, perhaps because pigs have bilateral occlusion and masseter activity.


Subject(s)
Jaw/physiology , Mammals/physiology , Mastication , Muscles/physiology , Animals , Biomechanical Phenomena
14.
Am J Clin Nutr ; 74(3): 343-7, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11522558

ABSTRACT

BACKGROUND: Intake of carbonated beverages has been associated with increased fracture risk in observational studies. The usual explanation given is that one or more of the beverage constituents increase urinary calcium. OBJECTIVE: We assessed the short-term effects on urinary calcium excretion of carbonated beverages of various compositions. DESIGN: An incomplete random block design was used to study 20-40-y-old women who customarily consumed > or =680 mL carbonated beverages daily. Four carbonated beverages were tested: 2 with caffeine and 2 without. Two contained phosphoric acid as the acidulant and 2 contained citric acid. The study included one neutral control (water) and one positive control (skim or chocolate milk). Serving size was 567 mL for the carbonated beverages and water and 340 mL for the milks. Beverages were consumed with a light breakfast after an overnight fast; no other foods were ingested until urine collection was complete. pH, titratable and total acidity, sodium, creatinine, and calcium were measured in 2-h (morning) fasting and 5-h postbeverage urine specimens. RESULTS: Relative to water, urinary calcium rose significantly only with the milks and the 2 caffeine-containing beverages. The excess calciuria was approximately 0.25 mmol, about the same as previously reported for caffeine alone. Phosphoric acid without caffeine produced no excess calciuria; nor did it augment the calciuria of caffeine. CONCLUSIONS: The excess calciuria associated with consumption of carbonated beverages is confined to caffeinated beverages. Acidulant type has no acute effect. Because the caffeine effect is known to be compensated for by reduced calciuria later in the day, we conclude that the net effect of carbonated beverage constituents on calcium economy is negligible. The skeletal effects of carbonated beverage consumption are likely due primarily to milk displacement.


Subject(s)
Caffeine/adverse effects , Calcium/urine , Carbonated Beverages/analysis , Fractures, Bone/etiology , Adult , Animals , Calcium/metabolism , Carbonated Beverages/adverse effects , Citric Acid/administration & dosage , Creatinine/urine , Fasting , Female , Fractures, Bone/metabolism , Humans , Hydrogen-Ion Concentration , Milk , Phosphoric Acids/administration & dosage , Risk Factors , Sodium/urine
15.
J Immunol ; 166(3): 1482-91, 2001 Feb 01.
Article in English | MEDLINE | ID: mdl-11160187

ABSTRACT

Osteoprotegerin (OPG) is a CD40-regulated gene in B cells and dendritic cells (DCs). We investigated the role of OPG in the immune system by generating opg(-/-) mice. Like its role as a regulator of bone metabolism, OPG also influences processes in the immune system, notably in B cell development. Ex vivo, opg(-/-) pro-B cells have enhanced proliferation to IL-7, and in opg(-/-) spleen, there is an accumulation of type 1 transitional B cells. Furthermore, opg(-/-) bone marrow-derived DCs are more effective in stimulating allogeneic T cells than control DCs. When challenged with a T-dependent Ag, opg(-/-) mice had a compromised ability to sustain an IgG3 Ag-specific response. Thus, in the immune system, OPG regulates B cell maturation and development of efficient Ab responses.


Subject(s)
B-Lymphocytes/immunology , Bone and Bones/metabolism , Glycoproteins/physiology , Receptors, Cytoplasmic and Nuclear/physiology , Animals , B-Lymphocyte Subsets/pathology , B-Lymphocytes/pathology , Bone and Bones/pathology , Cell Differentiation/genetics , Cell Differentiation/immunology , Dendritic Cells/immunology , Gene Targeting , Glycoproteins/biosynthesis , Glycoproteins/deficiency , Glycoproteins/genetics , Hematopoiesis/genetics , Hematopoiesis/immunology , Immunoglobulin Class Switching/genetics , Immunoglobulin D/biosynthesis , Immunoglobulin Isotypes/biosynthesis , Immunoglobulin M/biosynthesis , Lymphocyte Activation/genetics , Lymphocyte Activation/immunology , Lymphocyte Count , Lymphocytosis/genetics , Lymphocytosis/immunology , Lymphocytosis/pathology , Mice , Mice, Inbred Strains , Mice, Knockout , Osteoporosis/genetics , Osteoporosis/immunology , Osteoporosis/metabolism , Osteoprotegerin , Receptors, Cytoplasmic and Nuclear/biosynthesis , Receptors, Cytoplasmic and Nuclear/deficiency , Receptors, Cytoplasmic and Nuclear/genetics , Receptors, Tumor Necrosis Factor , T-Lymphocytes/immunology
16.
J Exp Biol ; 203(Pt 14): 2093-104, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10862722

ABSTRACT

Despite a number of previous biomechanical studies on the zygomatic arch, unanswered questions remain about its three-dimensional loading and growth. Using young miniature swine, we have for the first time recorded strains from both the medial and lateral aspects of the squamosal bone during mastication and masseter muscle stimulation. Strains from the zygomatic bone flange and zygomatic arch growth data were also obtained from the same animals. A second study on a younger group of animals examined the growth of the zygomatic flange following partial removal of the masseter. Strain data indicated that the squamosal bone is bent out-of-plane and that this pattern of loading is quite different from that of the adjacent zygomatic bone, which experiences much lower strains with little evidence of out-of-plane bending. Surprisingly, strains were higher in the zygomatic flange during contralateral chews and contralateral masseter stimulations than during ipsilateral chews/stimulations. These strains proved to arise from movement of the condyle, explaining why partial removal of the masseter had little effect on the growth of the flange. Other growth results indicated an approximately threefold greater rate of subperiosteal deposition on the lateral surface of the squamosal bone than on the zygomatic bone. This difference in growth rate is attributed to the presence of sutures that contribute to the lateral displacement of the zygomatic bone but not the squamosal bone. This explanation does not exclude the possibility that the rapid apposition on the lateral squamosal surface is regulated by the high surface strains that result from out-of-plane bending.


Subject(s)
Mastication/physiology , Zygoma/physiology , Animals , Electric Stimulation , Electromyography , Female , Fluorescent Dyes , Male , Masseter Muscle/growth & development , Masseter Muscle/physiology , Muscle Development , Stress, Mechanical , Swine , Swine, Miniature , Weight-Bearing , Zygoma/anatomy & histology , Zygoma/growth & development
17.
Am J Clin Nutr ; 71(5): 1166-9, 2000 May.
Article in English | MEDLINE | ID: mdl-10799379

ABSTRACT

BACKGROUND: Calcium-fortified soy milk is growing in popularity, particularly among vegetarians, but the bioavailability of its calcium was not previously known. Additionally, the validity of isotopic labeling methods for fortified liquid products had not been established. OBJECTIVES: The objectives of this study were to compare the bioavailability of the calcium in fortified soy milk with that of calcium in cow milk and to evaluate the method of labeling soy milk for bioavailability testing. DESIGN: A within-subject comparison of extrinsically labeled cow milk with intrinsically and extrinsically labeled soy milks was undertaken in 16 healthy men. In all tests, 300-mg Ca loads were given as a part of a light breakfast after an overnight fast. The milks were physically partitioned into liquid and solid phases to enable evaluation of tracer distribution. RESULTS: Calcium from intrinsically labeled soy milk was absorbed at only 75% the efficiency of calcium from cow milk. Extrinsic labeling of soy milk did not produce uniform tracer distribution throughout the liquid and solid phases and resulted in a 50% overestimate of true absorbability. CONCLUSION: Calcium-fortified soy milk does not constitute a calcium source comparable to cow milk, and extrinsic labeling of such calcium particulate suspensions does not produce the uniform tracer distribution needed for bioavailability testing. Hence, intrinsic labeling of the fortificant is required for such liquid suspensions.


Subject(s)
Calcium, Dietary/pharmacokinetics , Food, Fortified , Glycine max/chemistry , Adult , Animals , Beverages , Biological Availability , Calcium Phosphates/chemistry , Calcium Phosphates/metabolism , Calcium Radioisotopes/chemistry , Calcium Radioisotopes/metabolism , Calcium, Dietary/administration & dosage , Humans , Male , Middle Aged , Milk/chemistry , Milk/metabolism , Random Allocation , Scintillation Counting , Glycine max/metabolism , Spectrophotometry, Atomic
18.
J Clin Endocrinol Metab ; 85(12): 4635-8, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11134120

ABSTRACT

Five clinical studies of calcium intake, designed with a primary skeletal end point, were reevaluated to explore associations between calcium intake and body weight. All subjects were women, clustered in three main age groups: 3rd, 5th, and 8th decades. Total sample size was 780. Four of the studies were observational; two were cross-sectional, in which body mass index was regressed against entry level calcium intake; and two were longitudinal, in which change in weight over time was regressed against calcium intake. One study was a double-blind, placebo-controlled, randomized trial of calcium supplementation, in which change in weight during the course of study was evaluated as a function of treatment status. Significant negative associations between calcium intake and weight were found for all three age groups, and the odds ratio for being overweight (body mass index, >26) was 2.25 for young women in the lower half of the calcium intakes of their respective study groups (P: < 0.02). Relative to placebo, the calcium-treated subjects in the controlled trial exhibited a significant weight loss across nearly 4 yr of observation. Estimates of the relationship indicate that a 1000-mg calcium intake difference is associated with an 8-kg difference in mean body weight and that calcium intake explains approximately 3% of the variance in body weight.


Subject(s)
Body Weight/drug effects , Calcium, Dietary/administration & dosage , Adult , Aged , Aged, 80 and over , Body Mass Index , Calcium, Dietary/therapeutic use , Cross-Sectional Studies , Double-Blind Method , Female , Humans , Middle Aged , Osteoporosis/prevention & control
20.
J Morphol ; 242(2): 167-79, 1999 Nov.
Article in English | MEDLINE | ID: mdl-10521876

ABSTRACT

The growth and morphology of craniofacial sutures are thought to reflect their functional environment. However, little is known about in vivo sutural mechanics. The present study investigates the strains experienced by the internasal, nasofrontal, and anterior interfrontal sutures during masticatory activity in 4-6-month-old miniature swine (Sus scrofa). Measurements of the bony/fibrous arrangements and growth rates of these sutures were then examined in the context of their mechanical environment. Large tensile strains were measured in the interfrontal suture (1,036 microepsilon +/- 400 SD), whereas the posterior internasal suture was under moderate compression (-440 microepsilon +/- 238) and the nasofrontal suture experienced large compression (-1,583 microepsilon +/- 506). Sutural interdigitation was associated with compressive strain. The collagen fibers of the internasal and interfrontal sutures were clearly arranged to resist compression and tension, respectively, whereas those of the nasofrontal suture could not be readily characterized as either compression or tension resisting. The average linear rate of growth over a 1-week period at the nasofrontal suture (133.8 micrometer, +/- 50.9 S.D) was significantly greater than that of both the internasal and interfrontal sutures (39.2 micrometer +/- 11.4 and 65. 5 micrometer +/- 14.0, respectively). Histological observations suggest that the nasofrontal suture contains chondroid tissue, which may explain the unexpected combination of high compressive loading and rapid growth in this suture.


Subject(s)
Cranial Sutures/growth & development , Craniofacial Dysostosis , Mastication/physiology , Animals , Cranial Sutures/ultrastructure , Female , Linear Models , Male , Stress, Mechanical , Swine , Swine, Miniature
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