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Binocular rivalry in autistic and socially anxious adults. Front Psychiatry 2023; 14:1181797. [PMID: 37547197 PMCID: PMC10400451 DOI: 10.3389/fpsyt.2023.1181797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 06/05/2023] [Indexed: 08/08/2023] Open
Abstract
Background Social anxiousness is a pervasive symptom in both social anxiety disorder and autism spectrum conditions. Binocular rivalry, which occurs when different images are presented to each eye, has been used to explore how visual and cognitive processing differs across various clinical diagnoses. Previous studies have separately explored whether individuals with autism or anxiety experience binocular rivalry in ways that are different from neurotypical individuals. Methods We applied rivalry paradigms that are similar to those used in previous studies of autism and general anxiety to individuals experiencing symptoms of social anxiousness at clinical or subclinical levels. We also incorporated rivalrous stimuli featuring neutral and emotional facial valances to explore potential overlap of social processing components in social anxiety and autism. Results We hypothesized that higher levels of social anxiousness would increase binocular rivalry switch rates and that higher levels of autistic traits would decrease switch rates. However, stimulus condition did not affect switch rates in either diagnostic group, and switch rate was not significantly predictive of dimensional measures of either autism or social anxiety. Discussion This may suggest a common mechanism for atypical visual cognition styles previously associated with social anxiety and autism. Alternatively, differences in switch rates may only emerge at higher trait levels than reported by the participants in our studies. Furthermore, these findings may be influenced by sex differences in our unique sample.
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2
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Response of Turkey Poults to Soybean Lectin Levels Typically Encountered in Commercial Diets. 2. Effect on Intestinal Development and Lymphoid Organs. Poult Sci 2006; 85:870-7. [PMID: 16673765 DOI: 10.1093/ps/85.5.870] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Lectins are capable of altering intestinal morphology by binding to and disrupting the intestinal brush border membrane. They are also known to alter the weight of lymphoid organs. Therefore, we evaluated the effect of soybean lectin (SBL) on intestinal morphology and lymphoid organ weights of poults fed diets containing SBL. Dietary treatments evaluated in this study included a cornstarch and casein-based control (lectin-free) semipurified diet (PD) and semipurified diets containing 0.024 or 0.048% SBL (PDL and PDH, respectively). Experimental diets were fed from hatch to 14 d. Morphological evaluation of the intestine involved measurement of the villi height and perimeter, crypt depth, villus:crypt, and thickness of the muscle layer in the jejunum. Intestinal physical characteristics were also determined by measuring intestinal weight, length, and volume. Results indicated that 0.048% SBL in PDH increased villus:crypt and reduced total intestinal length in turkey poults. In addition, both the 0.024 and 0.048% dietary SBL levels reduced thymus weights. It was concluded that dietary SBL up to 0.048% enhanced intestinal development by increasing villus:crypt, but might alter the structural integrity of lymphoid organs.
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3
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Intestinal adaptation to diet in the young domestic and wild turkey (Meleagris gallopavo). Comp Biochem Physiol A Mol Integr Physiol 2006; 143:184-92. [PMID: 16406824 DOI: 10.1016/j.cbpa.2005.11.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2005] [Revised: 11/17/2005] [Accepted: 11/19/2005] [Indexed: 11/29/2022]
Abstract
The short-term effects of diet on jejunal growth, alanine transport rate, and leucine aminopeptidase activity (LAP) were compared in the domestic and wild turkey poult. One-day-old poults of each strain were fed diets of high vs., low protein, with carbohydrate varied to maintain isocaloric conditions. Prior to feeding, relative jejunal mass and alanine transport rates were not significantly different in the two turkey strains, whereas LAP activity was 270% higher in wild poults. After feeding for 72 h, relative jejunal mass doubled in both turkey strains. In domestic turkeys, alanine transport rate and LAP activity were reduced by approximately 42% and 25%, respectively, in poults fed a 24% protein-69% carbohydrate diet vs. a 49% protein-35% carbohydrate diet. Analysis of the combined data from feeding experiments revealed that alanine transport rate was not correlated with total food, protein or lipid intake, but was negatively correlated with carbohydrate consumption (P<0.05). In wild turkeys, neither alanine transport rate nor LAP activity were altered by diet. These results reveal that domestic turkey hatchlings can modulate protein digestive and absorptive functions as protein/carbohydrate composition of the diet changes and suggest that high dietary carbohydrate down-regulates the intestinal alanine transporter.
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4
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TGF-beta inhibits muscle differentiation through functional repression of myogenic transcription factors by Smad3. Genes Dev 2001; 15:2950-66. [PMID: 11711431 PMCID: PMC312830 DOI: 10.1101/gad.925901] [Citation(s) in RCA: 303] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Transforming growth factor-beta (TGF-beta) is a potent inhibitor of skeletal muscle differentiation, but the molecular mechanism and signaling events that lead to this inhibition are poorly characterized. Here we show that the TGF-beta intracellular effector Smad3, but not Smad2, mediates the inhibition of myogenic differentiation in MyoD-expressing C3H10T1/2 cells and C2C12 myoblasts by repressing the activity of the MyoD family of transcriptional factors. The Smad3-mediated repression was directed at the E-box sequence motif within muscle gene enhancers and the bHLH region of MyoD, the domain required for its association with E-protein partners such as E12 and E47. The repression could be overcome by supplying an excess of E12, and covalent tethering of E47 to MyoD rendered the E-box-dependent transcriptional activity refractory to the effects of Smad3 and TGF-beta. Smad3 physically interacted with the HLH domain of MyoD, and this interaction correlated with the ability of Smad3 to interfere with MyoD/E protein heterodimerization and binding of MyoD complexes to oligomerized E-box sites. Together, these results reveal a model for how TGF-beta, through Smad3-mediated transcriptional repression, inhibits myogenic differentiation.
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5
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ASHP survey of ambulatory care responsibilities of pharmacists in managed care and integrated health systems--2001. Am J Health Syst Pharm 2001; 58:2151-66. [PMID: 11760918 DOI: 10.1093/ajhp/58.22.2151] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The results of a 2001 national survey of the ambulatory care responsibilities of pharmacists in managed care organizations (MCOs) and integrated health systems are reported and compared with the results of similar surveys conducted in 1997 and 1999. Three hundred and seventy-six MCOs and integrated health systems participated in the telephone survey. The surveyelicited data about organizational structure and pharmacist functions in the ambulatory care environment. Survey respondents were asked about 24 specific ambulatory care pharmacist functions. The performance of functions was related to five "enabling" factors: pharmacists on interdisciplinary care teams, automated dispensing systems, integrated electronic medical records, very supportive medical staff, and very supportive senior management. Twenty previously measured functions decreased since 1999. Decreases were greatest in negotiating pharmaceutical contracts (-28%), administering immunizations (-27%), and immunization screening (-24%). Enabling factors supported continued expansion. Two clusters of functions, patient-related and population-related activities, were identified and supported differentially by enabling factors. Group-model and staff-model HMOs had the most enabling factors and the broadest scope of pharmacist functions. Independent practice associations had fewer enabling factors and a different mix of functions, with an emphasis on population-focused functions. Ambulatory care functions of pharmacists have expanded to new areas and have decreased in more traditional areas, perhaps because of the current pharmacist shortage and the increase in the number of prescriptions and patients.
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Ecotypic and genetic variation in poplar bark storage protein gene expression and accumulation. TREE PHYSIOLOGY 2001; 21:1289-1297. [PMID: 11696416 DOI: 10.1093/treephys/21.17.1289] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Bark storage proteins (BSP) store nitrogen (N) translocated from senescing leaves in autumn, and supply reduced N for spring growth. Expression of bsp and BSP accumulation are associated with short day photoperiod. To determine if photoperiod-associated bsp expression varies among poplars native to different latitudes, Populus deltoides Bartr. clones originating from six latitudes were grown under natural conditions at a common location. Relative amounts of BSP mRNA in these clones were measured at 2-week intervals from August 7 to October 16. The date of maximum BSP mRNA accumulation was correlated with latitude of origin, and maximum accumulation of BSP mRNA occurred earlier in clones native to northern latitudes than in clones native to southern latitudes. This pattern of variation is consistent with photoperiodic responses of plants native to temperate climates. Genotypic variations in BSP accumulation, bark protein concentration and bark N concentration were compared among clones of six hybrid poplar (Populus trichocarpa Torr. and Gray x P. deltoides) full-sib families (three F(2) families, two F(1) families and one BC(1) family) after 6 weeks in a short day photoperiod and at midwinter. Significant differences in BSP accumulation occurred among clones within four of the six full-sib families after 6 weeks in a short day photoperiod and also at midwinter for outdoor-grown plants. Bark protein and bark N concentrations also varied significantly among clones within certain families. In general, the greatest variation was found in F(2) and BC(1) families. Within several families, relative BSP amounts were positively correlated with bark protein concentration and total bark N concentration. These results indicate a role of photoperiod in regulating bsp expression and demonstrate a genetic component underlying seasonal BSP accumulation. The results could have significance in selecting for clones with improved N storage capacity and N-use efficiency.
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Activated notch inhibits myogenic activity of the MADS-Box transcription factor myocyte enhancer factor 2C. Mol Cell Biol 1999; 19:2853-62. [PMID: 10082551 PMCID: PMC84078 DOI: 10.1128/mcb.19.4.2853] [Citation(s) in RCA: 109] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/1998] [Accepted: 12/15/1998] [Indexed: 11/20/2022] Open
Abstract
Skeletal muscle gene expression is dependent on combinatorial associations between members of the MyoD family of basic helix-loop-helix (bHLH) transcription factors and the myocyte enhancer factor 2 (MEF2) family of MADS-box transcription factors. The transmembrane receptor Notch interferes with the muscle-inducing activity of myogenic bHLH proteins, and it has been suggested that this inhibitory activity of Notch is directed at an essential cofactor that recognizes the DNA binding domains of the myogenic bHLH proteins. Given that MEF2 proteins interact with the DNA binding domains of myogenic bHLH factors to cooperatively regulate myogenesis, we investigated whether members of the MEF2 family might serve as targets for the inhibitory effects of Notch on myogenesis. We show that a constitutively activated form of Notch specifically blocks DNA binding by MEF2C, as well as its ability to cooperate with MyoD and myogenin to activate myogenesis. Responsiveness to Notch requires a 12-amino-acid region of MEF2C immediately adjacent to the DNA binding domain that is unique to this MEF2 isoform. Two-hybrid assays and coimmunoprecipitations show that this region of MEF2C interacts directly with the ankyrin repeat region of Notch. These findings reveal a novel mechanism for Notch-mediated inhibition of myogenesis and demonstrate that the Notch signaling pathway can discriminate between different members of the MEF2 family.
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8
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Abstract
Metazoans contain multiple types of muscle cells that share several common properties, including contractility, excitability, and expression of overlapping sets of muscle structural genes that mediate these functions. Recent biochemical and genetic studies have demonstrated that members of the myocyte enhancer factor-2 (MEF2) family of MADS (MCM1, agamous, deficiens, serum response factor)-box transcription factors play multiple roles in muscle cells to control myogenesis and morphogenesis. Like other MADS-box proteins, MEF2 proteins act combinatorially through protein-protein interactions with other transcription factors to control specific sets of target genes. Genetic studies in Drosophila have also begun to reveal the upstream elements of myogenic regulatory hierarchies that control MEF2 expression during development of skeletal, cardiac, and visceral muscle lineages. Paradoxically, MEF2 factors also regulate cell proliferation by functioning as endpoints for a variety of growth factor-regulated intracellular signaling pathways that are antagonistic to muscle differentiation. We discuss the diverse functions of this family of transcription factors, the ways in which they are regulated, and their mechanisms of action.
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Abstract
The C57BL/6 (B6) mouse is more sensitive to the effects of a high-fat diet than the A/J strain. The B6 mouse develops severe obesity, hyperglycemia, and hyperinsulinemia when fed this dietary regimen. This study was conducted to determine the effects of dietary fat and sucrose concentrations on body composition and intestinal sucrase (EC 3.2.1.48) and maltase (EC 3.2.1.20) activity in these two mouse strains. High-fat diets, regardless of sucrose content, resulted in significant weight gain, higher body fat, and lower body protein and water content in both strains of mice. The shift toward higher body fat and lower protein and water content was far greater in the B6 strain. Low-fat, high-sucrose diets resulted in lower body weight in both strains, as well as significantly greater body protein content in B6 mice. Analysis of intestinal sucrase showed that the enzyme was less active in B6 mice when the diet was high in sucrose. Both sucrase and maltase had lower activity in the presence of high dietary fat in both mouse strains. The percent reduction of intestinal enzyme activity due to dietary fat was similar in both strains. The B6 mouse exhibits disproportionate weight gain and altered body composition on a high-fat diet. This coupled with the reduced body weight and increased body protein on a low-fat, high-sucrose diet suggests that factors-relative to fat metabolism rather than sucrose metabolism are responsible for obesity.
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The myogenic regulatory gene Mef2 is a direct target for transcriptional activation by Twist during Drosophila myogenesis. Genes Dev 1998; 12:422-34. [PMID: 9450935 PMCID: PMC316486 DOI: 10.1101/gad.12.3.422] [Citation(s) in RCA: 130] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/1997] [Accepted: 11/25/1997] [Indexed: 02/05/2023]
Abstract
MEF2 is a MADS-box transcription factor required for muscle development in Drosophila. Here, we show that the bHLH transcription factor Twist directly regulates Mef2 expression in adult somatic muscle precursor cells via a 175-bp enhancer located 2245 bp upstream of the transcriptional start site. Within this element, a single evolutionarily conserved E box is essential for enhancer activity. Twist protein can bind to this E box to activate Mef2 transcription, and ectopic expression of twist results in ectopic activation of the wild-type 175-bp enhancer. By use of a temperature-sensitive mutant of twist, we show that activation of Mef2 transcription via this enhancer by Twist is required for normal adult muscle development, and reduction in Twist function results in phenotypes similar to those observed previously in Mef2 mutant adults. The 175-bp enhancer is also active in the embryonic mesoderm, indicating that this enhancer functions at multiple times during development, and its function is dependent on the same conserved E box. In embryos, a reduction in Twist function also strongly reduced Mef2 expression. These findings define a novel transcriptional pathway required for skeletal muscle development and identify Twist as an essential and direct regulator of Mef2 expression in the somatic mesoderm.
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Multiple roles for the MyoD basic region in transmission of transcriptional activation signals and interaction with MEF2. Mol Cell Biol 1998; 18:69-77. [PMID: 9418854 PMCID: PMC121453 DOI: 10.1128/mcb.18.1.69] [Citation(s) in RCA: 121] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Establishment of skeletal muscle lineages is controlled by the MyoD family of basic helix-loop-helix (bHLH) transcription factors. The ability of these factors to initiate myogenesis is dependent on two conserved amino acid residues, alanine and threonine, in the basic domains of these factors. It has been postulated that these two residues may be responsible for the initiation of myogenesis via interaction with an essential myogenic cofactor. The myogenic bHLH proteins cooperatively activate transcription and myogenesis through protein-protein interactions with members of the myocyte enhancer factor 2 (MEF2) family of MADS domain transcription factors. MyoD-E12 heterodimers interact with MEF2 proteins to synergistically activate myogenesis, while homodimers of E12, which lack the conserved alanine and threonine residues in the basic domain, do not interact with MEF2. We have examined whether the myogenic alanine and threonine in the MyoD basic region are required for interaction with MEF2. Here, we show that substitution of the MyoD basic domain with that of E12 does not prevent interaction with MEF2. Instead, the inability of alanine-threonine mutants of MyoD to initiate myogenesis is due to a failure to transmit transcriptional activation signals provided either from the MyoD or the MEF2 activation domain. This defect in transcriptional transmission can be overcome by substitution of the MyoD or the MEF2 activation domain with the VP16 activation domain. These results demonstrate that myogenic bHLH-MEF2 interaction can be uncoupled from transcriptional activation and support the idea that the myogenic residues in myogenic bHLH proteins are essential for transmission of a transcriptional activation signal.
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12
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Abstract
Two lines of turkey poults, one selected for rapid growth at 16 wk of age (F line) and the other a randombred control line (RBC2) were used to investigate the effect of selection for rapid growth on jejunal O2 consumption and glucose transport as well as whole-body O2 consumption. All trials used unsexed poults and were designed as a randomized complete block with day and line as independent variables. In Trial 1, 120 turkey poults, fed a standard starter ration (25.5% CP), were used to examine the effect of selection on feed intake, body weight gain, and efficiency from hatching (Day 0) to 13 d of age. At Day 14, 36 of 60 birds from each line were killed to measure intestinal length and weight and jejunal O2 consumption after 18 h of feed deprivation. Compared with the RBC2 line, the F line had relatively shorter but heavier small intestinal segments when adjusted by 18 h feed-deprived body weight (FBW; P < 0.001). The F line consumed more O2 over the entire jejunum adjusted to FBW than RBC2 line (43.8 vs 34.6 nmol O2/min.g FBW; P < 0.001). Jejunal ouabain- and cycloheximide-sensitive O2 consumption were greater (P < 0.05) in the F line. In Trial 2, 16 14-d-old poults from each line were used to measure in vitro jejunal glucose transport rate. There was no difference in glucose transport of the jejunum (nanomoles per minute per gram of FBW) between the lines. In Trial 3, 20 poults from each line were used to measure whole-body O2 consumption at 7 to 10 d of age. The F and RBC2 lines had similar whole-body O2 consumption rate per gram of FBW. These data suggest that selection of turkeys for rapid growth at 16 wk of age did not increase efficiency of jejunal glucose uptake in 14-d-old turkey poults.
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Abstract
Myocyte enhancer factor 2 (MEF2) proteins serve as important muscle transcription factors. In addition, MEF2 proteins have been shown to potentiate the activity of other cell-type-specific transcription factors found in muscle and brain tissue. While transcripts for MEF2 factors are widely expressed in a variety of cells and tissues, MEF2 proteins and binding activity are largely restricted to skeletal, smooth, and cardiac muscle and to brain. This disparity between MEF2 protein and mRNA expression suggests that translational control may play an important role in regulating MEF2 expression. In an effort to identify sequences within the MEF2A message which control translation, we isolated the mouse MEF2A 3' untranslated region (UTR) and fused it to the chloramphenicol acetyltransferase (CAT) reporter gene. Here, we show by CAT assay that the MEF2A 3' UTR dramatically inhibits CAT gene expression in vivo and that this inhibition is due to an internal region within the highly conserved 3' UTR. RNase protection analyses demonstrated that the steady-state level of CAT mRNA produced in vivo was not affected by fusion of the MEF2A 3' UTR, indicating that the inhibition of CAT activity resulted from translational repression. Furthermore, fusion of the MEF2A 3' UTR to CAT inhibited translation in vitro in rabbit reticulocyte lysates. We also show that the translational repression mediated by the 3' UTR of MEF2A is regulated during muscle cell differentiation. As muscle cells in culture differentiate, the translational inhibition caused by the MEF2A 3' UTR is relaxed. These results demonstrate that the MEF2A 3' UTR functions as a cis-acting translational repressor both in vitro and in vivo and suggest that this repression may contribute to the tissue-restricted expression and binding activity of MEF2A.
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Abstract
PURPOSE To examine the effectiveness of percussion of the superficial temporal artery for identification of the external carotid artery (ECA). MATERIALS AND METHODS The temporal artery tap maneuver was performed on 324 carotid arteries (163 patients). Evidence for transmission of the effect of the temporal tap was sought in the pulsed Doppler ultrasound waveforms of the ECA, common carotid artery (CCA), and internal carotid artery (ICA). The location and severity of stenotic lesions were recorded. The relative amplitudes of the oscillations created by the tap were compared. RESULTS The temporal tap effect could be seen in 262 ECAs (81%), 174 CCAs (54%), and 106 ICAs (33%). The tap effect can be seen in the ICA at all grades of ICA disease. When the oscillations were seen in only one of the two major branches, that branch was always the ECA. When the temporal tap effect was found in the ICA, the amplitudes of the oscillations were the same as or greater than those of the ECA in 26% of cases. CONCLUSION Waveform oscillations from the temporal tap maneuver often can be found beyond the ECA in the CCA and ICA. Thus, the temporal tap alone may not reliably distinguish the ECA from the ICA or CCA.
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Selection for growth does not affect apparent energetic efficiency of jejunal glucose uptake in mice. J Nutr 1996; 126:2851-60. [PMID: 8914957 DOI: 10.1093/jn/126.11.2851] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Five-wk-old male mice from high growth (M16) and randomly bred control (ICR) lines, plus their reciprocal crosses, ICR x M16 and M16 x ICR, were used to investigate whether whole-body O2 consumption, jejunal respiration, jejunal glucose absorption and the apparent energetic efficiency of jejunal active glucose uptake in mice are altered by genetic selection for growth as well as by heterosis and maternal effects. Whole-body O2 consumption was measured in 12 mice from each line or cross. The mice were later killed for measurement of jejunal O2, using tissue respiration chambers and jejunal glucose transport determined by 3H-3-O-methylglucose accumulation. No heterosis or maternal effects were detected in jejunal glucose active transport and active glucose uptake. Selection for growth (M16 vs. ICR) increased daily gain (1.54 vs. 1.09 g, P < 0.001), small intestinal length and weight, but did not enhance jejunal glucose transport. The apparent energetic efficiency of jejunal active glucose uptake among lines was not different (54.0, 50.4, 51.6 and 47.1 nmol ATP expended/nmol glucose uptake for M16, ICR, M16 x ICR and ICR x M16, respectively, P > 0.63). Selection for growth in mice did not result in more energetically efficient jejunal glucose absorption.
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16
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Selection for body composition does not affect energetic efficiency of jejunal glucose uptake in mice. J Nutr 1996; 126:2861-6. [PMID: 8914958 DOI: 10.1093/jn/126.11.2861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Five-wk-old male mice from three lines were used to examine whether the apparent energetic efficiency of active jejunal glucose uptake in mouse jejunum is altered by genetic selection for different body composition. The mice lines were selected as follows: HE, high percentage of body fat with no change in body weight as a constraint; LF, low percentage of body fat; and RS, randomly bred control. Body weight was similar in all lines. Total jejunal O2 consumption and ouabain-sensitive O2 consumption were used to estimate the energy expenditure associated with glucose absorption and Na+/K(+)-ATPase activity. Tritiated 3-O-methyl-D-glucose was used to determine glucose uptake by mouse jejunum. Line LF, when compared with line HE, had lower body fat as indicated by epididymal fat pad weight (143 vs. 362 mg/mouse, P < 0.001). There were no significant differences in small intestinal weight, length and density (mg/cm) between LF and HE lines. Jejunal villus width was greater in line LF compared with line HE (115 vs. 92 microm, P < 0.002). Jejunal glucose transport and O2 consumption were not different between LF and HE lines. Ouabain-sensitive O2 consumption was not significantly different among the three lines. No differences were noted in the apparent energetic efficiency of active glucose uptake among lines.
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Cooperative transcriptional activation by the neurogenic basic helix-loop-helix protein MASH1 and members of the myocyte enhancer factor-2 (MEF2) family. J Biol Chem 1996; 271:26659-63. [PMID: 8900141 DOI: 10.1074/jbc.271.43.26659] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Establishment of skeletal muscle and neural cell types is controlled by families of myogenic and neurogenic basic helix-loop-helix (bHLH) proteins, respectively. Myogenic bHLH proteins have been shown to activate skeletal muscle transcription in collaboration with members of the myocyte enhancer factor-2 (MEF2) family of MCM1-agamous-deficiens-serum response factor (MADS)-box transcription factors, which are expressed in differentiated myocytes and neurons. Here, we show that the neurogenic bHLH protein MASH1 interacts with members of the MEF2 family and that this interaction, mediated by the DNA binding and dimerization domains of these factors, results in synergistic activation of transcription through either the MASH1 or the MEF2 DNA binding site. Consistent with their involvement in activation of neuronal gene expression, members of the MEF2 family are expressed in P19 embryonal carcinoma cells that have been induced to form neurons following treatment with retinoic acid. These results suggest that members of the MEF2 family perform similar roles in synergistic activation of transcription in myogenic and neurogenic lineages by serving as cofactors for cell type-specific bHLH proteins.
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18
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Abstract
Terminal hydrolysis of oligosaccharides at the small intestinal brush border yields monomeric glucose, most of which is then absorbed by the transepithelial route. This involves carrier-mediated processes requiring specialized functional proteins situated in the brush border (SGLT1) and basolateral (GLUT2) membranes. Glucose translocation at the enterocyte apical membrane is an active, Na(+)-dependent and saturable process, whereas exit from enterocytes is by facilitated diffusion and is energy-independent. Specific adaptation of glucose active transport occurs in response to changes in the proportion of glucose in the diet. The regulatory signals responsible for transport induction are imprecisely defined, although numerous protein hormones and gut regulatory proteins are implicated. Epidermal growth factor and peptide YY invoke up-regulation of jejunal active glucose transport in vivo. Recently, peptide YY has been shown to stimulate active glucose transport in mice without altering oxygen consumption of jejunal tissue. Several other peptides whose presence in tissues of the small bowel imply that they exert control over epithelial nutrient transport are considered, and the relevance of these physiological manipulations, with various regulatory peptides and hormones, to animal agriculture are discussed.
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19
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Abstract
There are four members of the myocyte enhancer binding factor 2 (MEF2) family of transcription factors, MEF2A, -B, -C, and -D, that have homology within an amino-terminal MADS box and an adjacent MEF2 domain that together mediate dimerization and DNA binding. MEF2A, -C, and -D have previously been shown to bind an A/T-rich DNA sequence in the control regions of numerous muscle-specific genes, whereas MEF2B was reported to be unable to bind this sequence unless the carboxyl terminus was deleted. To further define the functions of MEF2B, we analyzed its DNA binding and transcriptional activities. In contrast to previous studies, our results show that MEF2B binds the same DNA sequence as other members of the MEF2 family and acts as a strong transactivator through that sequence. Transcriptional activation by MEF2B is dependent on the carboxyl terminus, which contains two conserved sequence motifs found in all vertebrate MEF2 factors. During mouse embryogenesis, MEF2B transcripts are expressed in the developing cardiac and skeletal muscle lineages in a temporospatial pattern distinct from but overlapping with those of the other Mef2 genes. The mouse Mef2b gene maps to chromosome 8 and is unlinked to other Mef2 genes; its intron-exon organization is similar to that of the other vertebrate Mef2 genes and the single Drosophila Mef2 gene, consistent with the notion that these different Mef2 genes evolved from a common ancestral gene.
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MESH Headings
- Amino Acid Sequence
- Animals
- Base Sequence
- Cell Line
- Consensus Sequence
- Crosses, Genetic
- DNA-Binding Proteins/biosynthesis
- DNA-Binding Proteins/chemistry
- DNA-Binding Proteins/metabolism
- Embryo, Mammalian
- Enhancer Elements, Genetic
- Female
- Gene Expression Regulation, Developmental
- Genomic Library
- Heart/embryology
- MEF2 Transcription Factors
- Male
- Mice
- Mice, Inbred C57BL
- Molecular Sequence Data
- Muridae
- Muscle, Skeletal/embryology
- Muscle, Skeletal/metabolism
- Mutagenesis, Site-Directed
- Myocardium/metabolism
- Myogenic Regulatory Factors
- Open Reading Frames
- Promoter Regions, Genetic
- Recombinant Proteins/biosynthesis
- Recombinant Proteins/metabolism
- Sequence Homology, Amino Acid
- Trans-Activators/biosynthesis
- Transcription Factors/biosynthesis
- Transcription Factors/chemistry
- Transcription Factors/metabolism
- Transcription, Genetic
- Transfection
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The effect of hydrocortisone and thyroxine on development of calcium homeostasis in embryonic intestinal epithelium. EXPERIENTIA 1996; 52:558-63. [PMID: 8698089 DOI: 10.1007/bf01969728] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Cytoplasmic Ca2+ concentration of epithelial cells from 14-day embryonic chick duodena decreased during 72 h of organ culture to a value 54% of that found at 17 days in vivo. The ability of cells to maintain a constant Ca2+ concentration when challenged with high extracellular calcium was also significantly reduced. Addition of 1 microM hydrocortisone during culture restored both parameters of Ca2+ homeostasis to that of 16-day uncultured duodena, and rise in cytoplasmic Ca2+ was significant within 4 h of hormone treatment. Thyroxine influenced epithelial Ca2+ similarly, but to a lesser degree and only after 48-72 h of culture. These data indicate that glucocorticoids, and possibly thyroid hormones, influence the development of calcium homeostasis in intestinal epithelium.
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Mutational analysis of the DNA binding, dimerization, and transcriptional activation domains of MEF2C. Mol Cell Biol 1996; 16:2627-36. [PMID: 8649370 PMCID: PMC231253 DOI: 10.1128/mcb.16.6.2627] [Citation(s) in RCA: 160] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
There are four members of the myocyte enhancer factor 2 (MEF2) family of transcription factors in vertebrates, MEF2A, -B, -C, and -D, which have homology within a MADS box at their amino termini and an adjacent motif known as the MEF2 domain. These factors activate muscle gene expression by binding as homo- and heterodimers to an A/T-rich DNA sequence in the control regions of muscle-specific genes. To understand the mechanisms of muscle gene activation of MEF2 factors, we generated a series of deletion and site-directed mutants of MEF2C. These mutants demonstrated that the MADS and MEF2 domains mediate DNA binding and dimerization, whereas the carboxyl terminus is required for transcriptional activation. Amino acids that are essential for MEF2 site-dependent transcription but which do not affect DNA binding were also identified in the MEF2 domain. This type of positive-control mutant demonstrates that the transcription activation domain of MEF2C, although separate from the MEF2 domain, is dependent on this domain for transcriptional activation through the MEF2 site. MEF2 mutants that are defective for DNA binding act as dominant negative mutants and can inhibit activation of MEF2-dependent genes by wild-type MEF2C.
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Abstract
Members of the myocyte enhancer factor-2 (MEF2) family of MADS domain transcription factors cannot induce myogenesis in transfected fibroblasts, but when coexpressed with the myogenic basic-helix-loop-helix (bHLH) proteins MyoD or myogenin they dramatically increase the extent of myogenic conversion above that seen with either myogenic bHLH factor alone. This cooperativity required direct interactions between the DNA-binding domains of MEF2 and the myogenic bHLH factors, but only one of the factors needed a transactivation domain, and only one of the factors needed to be bound to DNA. These interactions allow either factor to activate transcription through the other's binding site and reveal a novel mechanism for indirect activation of gene expression via protein-protein interactions between the DNA-binding domains of heterologous classes of transcription factors.
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Abstract
PURPOSE To determine the clinical importance and origin of a bifid configuration of the fetal sacrum seen during routine fetal sonography. MATERIALS AND METHODS An apparent bifid malformation of the sacral spine was seen in 24 fetuses at antenatal sonography. An attempt was made to recreate this configuration prospectively in 111 consecutive second- and third-trimester fetuses. Three cadavers were also imaged to determine the origin of this configuration. RESULTS Outcome information was available for 22 of the 24 fetuses; all fetuses were normal. In the prospective study, the bifid sacrum configuration was recreated in 75 of the 111 fetuses studied. The configuration could never be produced earlier than 20 weeks gestational age, was seen in some fetuses at 20-25 weeks, and could always be seen after 25 weeks. Findings from imaging studies of the three cadavers revealed that this configuration was dependent on the demonstration of the alar ossification centers of the sacral vertebra. CONCLUSION The bifid sacrum artifact is a skewed representation of normal anatomy and should not be interpreted as a true anomaly.
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The mouse MRF4 promoter is trans-activated directly and indirectly by muscle-specific transcription factors. J Biol Chem 1995; 270:2889-92. [PMID: 7852366 DOI: 10.1074/jbc.270.7.2889] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
MRF4 is a member of the basic helix-loop-helix (bHLH) family of muscle-specific transcription factors, which also includes MyoD, myogenin, and myf5. The myocyte enhancer binding factor 2 (MEF2) proteins also serve as important muscle-specific transcription factors. In addition to activating the expression of many muscle-specific structural genes, various members of these two classes of proteins activate their own expression and the expression of each other in a complex transcriptional network that results in the establishment and maintenance of the muscle phenotype. To begin to determine how the expression of MRF4 is regulated by other muscle-specific transcription factors, we have isolated a region of the MRF4 gene that confers muscle-specific expression and have analyzed this promoter region for cis-acting elements involved in trans-activation by the myogenic bHLH and MEF2 transcription factors. Here, we show that in 10T1/2 fibroblasts the MRF4 promoter is trans-activated by myogenin, MyoD, myf5, and by the MEF2 factors, but that MRF4 does not activate expression of its own promoter. Myogenin activated the MRF4 promoter directly by an E box-dependent mechanism, while MEF2 factors activated the promoter through an indirect pathway. The E box-dependent regulation of the MRF4 promoter is in contrast to the regulation of the myogenin and MyoD promoters and may represent a mechanism for the differential expression of these factors during myogenesis.
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Abstract
Small intestinal glucose absorption and gastrointestinal morphology were compared in adult bovine somatotropin transgenic (MT-bGH) and control mice. The MT-bGH mice were 57% heavier than controls, although both groups consumed comparable amounts of food during the 5 d before transport measurements were made. Stomach, cecum and colon were 98, 53, and 81% heavier (P < 0.001), and small intestinal tract 52% heavier and 27% longer in MT-bGH than in control mice (P < 0.001). As a proportion of live weight, MT-bGH mice tended to have a shorter small intestine than controls (P < 0.07), whereas there was no difference for either small or large bowel relative weights. Villus dimensions, crypt depth and thickness of external muscle layers in the jejunum were not significantly different in control and MT-bGH mice. Active glucose transport rate per milligram of jejunum was 24% less than in control mice (P < 0.05). Jejunal active glucose transport rate per gram of live weight in MT-bGH mice was approximately half that of control mice. The larger small intestinal mass of MT-bGH mice compensated for the reduced rate of glucose transport per unit weight of intestine such that there was no significant difference in total small intestinal tract glucose transport between control and MT-bGH mice. These results suggest that there are substantial differences in nutrient absorptive efficiency between intestinal tract from MT-bGH and control mice.
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Duodenal calcium uptake, femur ash, and eggshell quality decline with age and increase following molt. Poult Sci 1994; 73:1590-6. [PMID: 7816734 DOI: 10.3382/ps.0731590] [Citation(s) in RCA: 105] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
An experiment was conducted to test the hypothesis that the decline in eggshell quality over time during egg production, and its improvement after molting, paralleled the rate of calcium uptake by the duodenum of the laying hen. In vitro duodenal calcium uptake rate and femur ash (percentage of femur weight) were determined at 37, 45, 51, 58, 68, and 72 wk of age. Percentage shell and shell thickness (millimeters) were determined at 22, 29, 36, 44, 50, 57, and 71 wk of age. Molt was induced at 63 wk of age. Three commercial strains DeKalb XL-Link, ISA/Babcock B-300V, and Hy-Line W-36 were compared. There were no differences in duodenal calcium uptake rate among strains. There was a significant decline (P < .01) in duodenal calcium uptake from 408 pmol/mg tissue per min at 37 wk of age to 329 pmol/mg per min at 58 wk of age. Femur ash decreased (P < .01) from 50.8% at 37 wk of age to 47.6% at 58 wk of age. Percentage shell and shell thickness declined (P < .01) from 9.79% and .403 mm at 22 wk of age to 8.88% and .373 mm at 57 wk of age, respectively. After the induced molt, duodenal calcium uptake increased (P < .01) to 402 pmol/mg tissue per min, and percentage shell and shell thickness increased (P < .01) to 10.23% and .389 mm, respectively. Duodenal calcium uptake increased immediately postmolt, whereas femur ash did not increase until 72 wk of age (P < .01).
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Abstract
In 1989, the American Cancer Society funded three Community Cancer Detection, Education and Prevention Demonstrations Projects for socioeconomically disadvantaged populations in Miami, Harlem, and West Oakland. Each project has demonstrated that by using a multifunction, multisite cancer control model with an action theory that integrates individual and structural influences, many barriers to screening and follow-up can be minimized.
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Abstract
The effects of epidermal growth factor on intestinal glucose transport were examined in mice. Glucose transport measurements were performed using an in vitro assay system that estimated the rate of accumulation of [3H]3-O-methyl-D-glucose. In Experiment 1, two-mo-old male and female mice were subcutaneously injected once daily with 0, 150 or 300 micrograms epidermal growth factor/kg body weight for 3 d. Jejunal glucose active transport was increased in a dose-dependent manner. There were no gender-related differences in intestinal glucose transport or the response to exogenous epidermal growth factor. In Experiment 2, 2-, 10- and 18-mo-old mice were administered 0 or 300 micrograms epidermal growth factor/kg body weight using a treatment similar to that used in Experiment 1. Active intestinal glucose transport was 30% greater in response to epidermal growth factor in each of the three age groups. Ouabain-sensitive and -insensitive jejunal oxygen consumption was increased in response to epidermal growth factor such that total jejunal respiration was stimulated 15 to 31%. The epidermal growth factor related percentage increase in glucose absorption was similar to the percentage increase in oxygen consumption such that the apparent energetic efficiency of glucose transport was unaffected. In both experiments, the active component of glucose transport was increased by epidermal growth factor while passive transport was not affected. Jejunal morphology and mucosal DNA and protein concentration were not altered by epidermal growth factor treatment. Epidermal growth factor-induced increases in intestinal absorption was not attributable to mucosal hyperplasia.
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Abstract
Vesicular stomatitis virus infection causes a rapid and potent inhibition of both host transcription and translation. Recently, the viral matrix (M) protein was shown to inhibit host-directed transcription in vivo in the absence of any other viral component (B. L. Black and D. S. Lyles, J. Virol. 66:4058-4064, 1992). The goal of this study was to determine the effect of M protein on host-directed translation. In vitro-transcribed mRNAs encoding M protein and chloramphenicol acetyltransferase (CAT) were cotransfected into BHK cells to determine the effect of M protein expression on translation of CAT mRNA. The results presented here show that M protein did not inhibit host-directed translation of CAT mRNA. On the contrary, this study gave the unexpected result that M protein actually stimulated host-directed translation under the same conditions in which it potently inhibited host-directed transcription. Under these conditions, the combined effect on host gene expression was a greater-than-20-fold inhibition. Furthermore, the enhancement of host translation mediated by M protein was genetically correlated with M protein's ability to inhibit host transcription. Thus, the results of this study establish that M protein does not inhibit host protein synthesis under the same conditions in which it potently inhibits host transcription and suggest that the inhibition of transcription and that of translation by vesicular stomatitis virus require separate viral gene products.
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The role of vesicular stomatitis virus matrix protein in inhibition of host-directed gene expression is genetically separable from its function in virus assembly. J Virol 1993; 67:4814-21. [PMID: 8392615 PMCID: PMC237868 DOI: 10.1128/jvi.67.8.4814-4821.1993] [Citation(s) in RCA: 87] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Recently, the vesicular stomatitis virus matrix (M) protein has been shown to be capable of inhibition of host cell-directed transcription in the absence of other viral components (B. L. Black and D. S. Lyles, J. Virol. 66:4058-4064, 1992). M protein is a major structural protein that is known to play a critical role in virus assembly by binding the helical ribonucleoprotein core of the virus to the cytoplasmic surface of the cell plasma membrane during budding. In this study, two M protein mutants were tested to determine whether the inhibition of host transcription by M protein is an indirect effect of its function in virus assembly or whether it represents an independent function of M protein. The mutant M protein of the conditionally temperature-sensitive (ts) vesicular stomatitis virus mutant, tsO82, was found to be defective in its ability to inhibit host-directed gene expression, as shown by its inability to inhibit expression of a cotransfected target gene encoding chloramphenicol acetyltransferase. The ability of the tsO82 M protein to function in virus assembly was similar to that of wild-type M protein, as shown by its ability to complement the group III ts M protein mutant, tsO23. Another mutant, MN1, which lacks amino acids 4 to 21 of M protein demonstrated that the abilities of M protein to inhibit chloramphenicol acetyltransferase gene expression and to localize to the nucleus were unaffected by deletion of this lysine-rich amino-terminal region but that the ability to function in virus assembly was ablated. Thus, the two M protein mutants examined in this study exhibited complementary phenotypes: tsO82 M protein functioned in virus assembly but was defective in inhibition of host-directed gene expression, while MN1 M protein functioned in inhibiting gene expression but was unable to function in virus assembly. These data demonstrate that the role of M protein in inhibition of host transcription can be separated genetically from its role in virus assembly.
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Abstract
Discussed herein are the constraints of nutrient delivery from the gastrointestinal tract that are placed on postabsorptive synthetic processes in highly selected strains of domestic livestock or livestock treated with growth promotants exogenously or via transgenic manipulation. Emphasis is placed on the discussion of recent advances in the knowledge of the regulation and manipulation of digestion and the absorption by the intestinal epithelium. Slaframine, a muscarinic exocrine secretagogue with a high affinity for the gastrointestinal tract, and epidermal growth factor may have practical potential for the manipulation of digestion and absorption, respectively. Special consideration is given to energetic considerations that must accompany any manipulation of gastrointestinal function. Down-regulation and up-regulation of mechanisms must be equally considered as this area is explored further.
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Report on the American Cancer Society Workshop on Community Cancer Detection, Education, and Prevention Demonstration Projects for Underserved Populations. CA Cancer J Clin 1993; 43:226-33. [PMID: 8324655 DOI: 10.3322/canjclin.43.4.226] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The American Cancer Society has been funding six pilot projects organized with the stated purpose of demonstrating how to implement cancer prevention and control projects for socioeconomically disadvantaged and underserved populations. This article reports on the results of a workshop held to evaluate project experiences and develop recommendations for the future.
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Development of Ca2+ homeostasis in epithelial cells from embryonic and neonatal intestine. THE AMERICAN JOURNAL OF PHYSIOLOGY 1992; 263:G371-9. [PMID: 1415549 DOI: 10.1152/ajpgi.1992.263.3.g371] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The fluorescent probe fura-2 was used to assay Ca2+ levels in epithelial cell suspensions from embryonic and neonatal chick duodenum. Cell preparations maintained high viability, completely hydrolyzed fura-2/AM to fura-2, retained 92% of cellular fura-2 within the cytoplasmic compartment, and gave low autofluorescence values during assay. Fura-2 leakage from loaded cells occurred at all ages, but could be corrected for in subsequent calculations of cellular Ca2+. Cytoplasmic Ca2+ concentration was 76-80 nM in cells from 14- to 16-day embryonic intestine, rose significantly to 92-98 nM at 17-20 days, and reached 209 nM at 1-day post-hatch when assayed in buffers containing 1.3 mM Ca2+. The developmental rise in cytoplasmic Ca2+ was accompanied by an enhanced ability of cells to maintain a constant Ca2+ concentration at increased levels of extracellular Ca2+ and by a highly correlated rise in alkaline phosphatase (ALP) activity. Epithelial Ca2+ subsequently decreased to the "adult" value of 133-142 nM and was constant along the crypt-villus axis of neonatal intestine. These results verify that fura-2 can be used to compare baseline cytoplasmic Ca2+ values of epithelial cells from developing intestine, reveal that significant changes in Ca2+ homeostasis occur during ontogeny, and suggest that epithelial Ca2+ may modulate ALP activity during the differentiation of embryonic enterocytes.
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Vesicular stomatitis virus matrix protein inhibits host cell-directed transcription of target genes in vivo. J Virol 1992; 66:4058-64. [PMID: 1318397 PMCID: PMC241208 DOI: 10.1128/jvi.66.7.4058-4064.1992] [Citation(s) in RCA: 119] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Infection by vesicular stomatitis virus (VSV) results in a rapid inhibition of host cell transcription and translation. To determine whether the viral matrix (M) protein was involved in this inhibition of host cell gene expression, an M protein expression vector was cotransfected with a target gene vector, encoding the target gene, encoding chloramphenicol acetyltransferase (CAT). Expression of M protein caused a decrease in CAT activity in a gene dosage-dependent manner, and inhibition was apparent by 12 h posttransfection. The inhibitory effect of M protein was quite potent. The level of M protein required for a 10-fold inhibition of CAT activity was less than 1% of the level of M protein produced during the sixth hour of VSV infection. Northern (RNA) analysis of cotransfected cells showed that expression of M protein caused a reduction in the steady-state level of the vector-encoded mRNAs. Expression of both CAT and M mRNAs was reduced in cells cotransfected with a plasmid encoding M protein, indicating that expression of small amounts of M protein from plasmid DNA inhibits further expression of both M and CAT mRNAs. Nuclear runoff transcription analysis demonstrated that expression of M protein inhibited transcription of the target genes. This is the first report of a viral gene product which is capable of inhibiting transcription in vivo in the absence of any other viral component.
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Isolation of Nocardia asteroides from respiratory specimens by using selective buffered charcoal-yeast extract agar. J Clin Microbiol 1992; 30:1320-2. [PMID: 1583139 PMCID: PMC265276 DOI: 10.1128/jcm.30.5.1320-1322.1992] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Nocardiosis is difficult to diagnose clinically and by laboratory methods. A patient presented with disease compatible with pulmonary malignancy, but Nocardia asteroides was isolated on buffered charcoal-yeast extract agar. Investigation revealed that this medium may be a suitable selective primary isolation medium for Nocardia species from respiratory specimens.
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Medicare and Medicaid fraud and abuse regulations. AMERICAN JOURNAL OF HOSPITAL PHARMACY 1991; 48:2434-7. [PMID: 1746579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Specific business arrangements that are protected under legislation and regulations governing parties doing business with Medicare or Medicaid are discussed. Regulations implementing the Medicare and Medicaid Patient Protection Act of 1987 specify practices and activities that are not subject to criminal penalties under the antikickback provisions of the Social Security Act or to exclusion from Medicare or state health-care programs. As of July 29, 1991, all organized health-care settings that receive payments from either Medicare or state health-care programs must comply with these regulations. The final rule sets forth "safe harbors"--exceptions to prohibitions against (1) kickbacks, bribes, rebates, and other illegal activities involving remunerations for patient referrals and (2) inducements to purchase or lease goods paid for by Medicare or state health-care programs. The safe harbors comprise 11 broad categories--investment interests, space rental, equipment rental, personal services and management contracts, purchase of a medical practice, referral services, warranties, discounts, employees, group purchasing organizations, and waiver of deductibles and coinsurance. Implications for pharmacy are discussed. These regulations will affect the purchase of pharmaceuticals by institutional pharmacies. Each institution should review its current practices to determine whether they are within the safe harbors.
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Is there a chiropractic science? J Manipulative Physiol Ther 1991; 14:442-4. [PMID: 1940680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Abstract
The cancer patient's perceptions about treatment, prognosis, and long-term care have emerged in the context of interaction with the changing healthcare system. A brief overview of cancer patients' perceptions regarding their disease and subsequent care is provided. The economic, organizational, and technological environment in which this care is provided and the patient's perceptions of that environment are discussed. In addition to economic pressures, the ever-increasing number of cancer patients, prolonged survival, and patients' perceptions have created changes in the healthcare system. These changes are mediated by important socioeconomic, cultural, and demographic characteristics of the cancer patient. Recommendations to address these changes are discussed.
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Abstract
Because life-style patterns affect many cancer risks, research on health-risk behavior and behavior change is critical to cancer prevention. This report recommends priorities for the next decade of psychosocial research on cancer prevention and detection. The leading priority for future research is to fill gaps in basic knowledge left by the rush to intervention and outcome studies. Such research must be theoretically driven and should aim to develop broad principles applicable to diverse health behaviors. Studies that include relevant process data on various stages of behavior change are considered more desirable than simple outcome studies. Epidemiologic investigations should be expanded to include measures of relevant behaviors, so that their impact on clinical outcomes might be established. More research is needed on lay perception of health risks and on individual and health-system barriers to effective cancer prevention and detection. Studies that address the needs of minority and underprivileged populations are crucial. Funding agencies' narrow categorical mandates impede interdisciplinary research on multiple risk factors and their interactions; these boundaries must be relaxed to promote such approaches. Funding agencies should also consider basic research as a long-term investment towards the development of effective interventions.
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Focal toxicity of oxysterols in vascular smooth muscle cell culture. A model of the atherosclerotic core region. THE AMERICAN JOURNAL OF PATHOLOGY 1990; 137:425-34. [PMID: 2201200 PMCID: PMC1877599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Cell necrosis and reactive cellular processes in and near the atherosclerotic core region might result from short-range interactions with toxic lipids. To model these interactions in cell culture, focal crystalline deposits of cholestane-3 beta,5 alpha,6 beta-triol, 25-OH cholesterol, and cholesterol were overlaid by a collagen gel, on which canine aortic smooth muscle cells were seeded. Oxysterols, but not cholesterol, caused focally decreased plating efficiency and cell death, leading to the formation of a persistent circular gap in the cell culture. Cholestanetriol was largely removed from the culture dishes over 3 to 4 weeks, whereas cholesterol and 25-OH cholesterol were largely retained. Smooth muscle cells were motile even in proximity to oxysterol crystals, with occasional suicidal migration toward the crystals. Chemoattraction, however, could not be demonstrated. Despite toxicity, cholestanetriol did not appear to alter the fraction of cells exhibiting 3H-thymidine uptake, even in areas close to the crystals. Thus, oxysterols may be toxic to some cells, without causing major impairment of the migration and proliferation of nearby cells. This would allow the simultaneous occurrence of cell death and proliferation evident in atherosclerosis.
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Abstract
Atherosclerotic lipid deposits found in the core region of fibrous plaques are almost entirely extracellular, but it is not known whether they are derived from necrosis of cells containing accumulated lipid or from direct extracellular lipid accumulation. New evidence pertaining to this question has been obtained through the use of recently developed techniques for preserving and staining lipids in electron microscopy, and through a detailed morphologic and chemical examination of human aortic fibrolipid lesions, which are progenitor lesions for fibrous plaques. The evidence favours a substantial role, perhaps a dominant role, for extracellular lipid accumulation in the formation of the fibrous plaque core region.
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Abstract
The potential role of calcium as a regulator of goblet cell differentiation was tested by culturing duodenal explants from 14-day chicken embryos in media containing a range of calcium concentrations. Extracellular calcium in vitro approximated the range of plasma calcium concentration that was found to rise by 16% during the third week of embryonic development. As ionic calcium was increased from 0.9 to 2.0 mM in 48-h cultures, the number of goblet cells per 100 ridges increased progressively from 29 +/- 2.2 to 158 +/- 6.9 while attaining a distribution on the previllous ridges similar to that in ovo. The rate of goblet cell differentiation in vitro exceeded that in ovo when extracellular calcium was increased to 1.1 mM and was maximal at 1.6-2.0 mM calcium. Neither the growth of previllous ridges nor gross morphology of the tissue was altered as extracellular calcium was increased. Goblet cell differentiation in 1.3 mM calcium was stimulated by 0.1 microM calcium ionophore and inhibited by the calmodulin antagonist trifluoperazine, indicating an intracellular site for calcium action. These results indicate that calcium plays a primary role in regulating goblet cell differentiation in embryonic intestine and suggest that rising levels of plasma calcium influence the rate of differentiation in ovo.
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Preparation of microvillus membrane vesicles from the intestine of embryonic and young chicks. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. B, COMPARATIVE BIOCHEMISTRY 1989; 93:39-48. [PMID: 2752732 DOI: 10.1016/0305-0491(89)90213-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
1. A procedure is described for the isolation of microvillus membranes from 19-day old embryonic, newly hatched, and 2-day old chicken intestine. 2. The magnesium concentration of epithelial cell homogenates is shown to be a crucial factor in obtaining membranes of equal purity from the three age groups. 3. Microvillus membranes are purified 20-25 fold over the original homogenate and form vesicles which are tightly sealed based on the Na+-dependent accumulation of glucose to levels four to five times equilibrium values. 4. These membrane preparations should prove useful in future studies concerning the embryonic and neonatal development of microvillus enzymes and nutrient transport systems in the chicken.
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Influence of hormones on glycogen and glucose metabolism in embryonic chick intestine. THE AMERICAN JOURNAL OF PHYSIOLOGY 1988; 254:G65-73. [PMID: 3337234 DOI: 10.1152/ajpgi.1988.254.1.g65] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Previous studies on the development of embryonic intestine in vitro have revealed a stimulation of epithelial differentiation by the hormones hydrocortisone (HC) and thyroxine (T4). To determine whether these hormones also influence epithelial metabolism, duodena from 14-day-old chicken embryos were cultured for 72 h in the absence of hormones (controls) or in the presence of 1 nM T4 or 1 microM HC. In control cultures, glycogen accumulated within the duodenal epithelium to the level found at 17 days in vivo. T4 reduced glycogen accumulation to 34% of control values, whereas HC increased epithelial glycogen content by 45%. These hormonal effects were due, in part, to modulation of glycogen degradation. In T4 cultures, glucose oxidation activities within the epithelial layer and submucosal tissue were 300 and 140% of control values, respectively, and glucose utilization (removal from the culture medium) was increased. HC significantly decreased both glucose oxidation activity within the submucosal tissue and glucose utilization. These results are consistent with the hypothesis that HC regulates the early phase of epithelial differentiation that is characterized by low metabolic rate and accumulation of energy stores, whereas T4 elicits the prehatching phase of differentiation that is correlated with an increase in metabolic rate and utilization of stored products.
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Development of glucose active transport in embryonic chick intestine. Influence of thyroxine and hydrocortisone. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. A, COMPARATIVE PHYSIOLOGY 1988; 90:379-86. [PMID: 2901307 DOI: 10.1016/0300-9629(88)90205-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
1. Glucose active transport is detectable in 12-day-old embryonic chick duodenum and increases at least 11-fold after 4 days of postnatal life. 2. Glucose active transport develops at the in vivo rate in 72-hr cultures of 14-day embryonic duodenum. 3. In the presence of either 1 nM thyroxine or 1 microM hydrocortisone in vitro, glucose active transport reaches levels approximately 200% of control values (equivalent to 18-19 day levels in vivo). 4. Thyroxine and hydrocortisone act by different mechanisms based on their antagonistic interaction and differences in time course of action, requirement for protein synthesis and modulation by extracellular calcium.
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Hospital diversification: how to involve the pharmacy. AMERICAN JOURNAL OF HOSPITAL PHARMACY 1987; 44:1059-68. [PMID: 3605115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Participation by hospital pharmacy departments in planning and development of diversified services is described. Diversification requires market planning. Seven basic marketing steps are identification of mission, goals, and objectives; identification of growth strategies (market penetration, market development, product development, and diversification); market analysis of external factors (size, growth, and logistics; reimbursement and financial considerations; competition; regulatory issues; and legal issues); market analysis of internal factors (departmental organization and reporting lines, demographics of the institution, and costs and productivity associated with the new service); program development and design; implementation; and evaluation. Hospitals can diversify by expanding acute-care services through management contracts and mergers; developing new services to include long-term-care, ambulatory-care, occupational-health, and wellness programs; starting other health-care ventures, such as consulting, continuing medical education, and continuing education for nurses; and expanding into non-health-care businesses. Vertical diversification is finding new markets for existing services; horizontal diversification is development of new services for new markets. To diversify, an institution may need to change its corporate structure; it may form a family of corporations that includes a university, nonprofit hospitals, holding companies, for-profit corporations, joint ventures, and service organizations. Through diversification, institutions and pharmacy departments can create alternative sources of funding and offer more comprehensive services to patients.
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Home health care. Ann Intern Med 1987; 106:643. [PMID: 3826980 DOI: 10.7326/0003-4819-106-4-643_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
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Impact of PROs on hospitals and pharmacy practice. AMERICAN JOURNAL OF HOSPITAL PHARMACY 1987; 44:77-84. [PMID: 3548342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Controversial issues in home health care: a roundtable discussion. AMERICAN JOURNAL OF HOSPITAL PHARMACY 1986; 43:933-46. [PMID: 3706341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Controversial issues in home health care (HHC) were discussed by a panel of four individuals involved in or knowledgeable about HHC. The panel addressed the following issues: reluctance of health professionals to participate in home care, challenges in providing HHC services, assigning responsibility for HHC services, reimbursement considerations in joint-venture arrangements, assuming fiscal responsibility for unreimbursed care, selecting HHC providers, defining patient rights, selecting drug products for home-care patients, competing with community pharmacists, circumvention of pharmacist input in preparation of solutions for home infusion, and the future of HHC. Hospital pharmacists who plan to become involved or are already involved in providing HHC services should become familiar with these controversial issues.
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