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Lee SC, Jaffar ZH, Wan KS, Holgate ST, Roberts K. Regulation of pulmonary T cell responses to inhaled antigen: role in Th1- and Th2-mediated inflammation. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1999; 162:6867-79. [PMID: 10352309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
DO11.10 transgenic mice, expressing an OVA-specific TCR, were used to study pulmonary T cell responses to inhaled Ags. Before OVA inhalation, the activation of lung parenchymal T cells elicited both strong proliferative responses and IL-2 production. However, following Ag inhalation the proliferative responses of the lung T cells, when restimulated in vitro with OVA323-339 peptide or immobilized anti-CD3, were severely attenuated and associated with a decrease in the level of production of IL-2 but not IFN-gamma. Such immune regulation was tissue-specific, because T cell responses in the lymph nodes and spleens were normal. This dramatic aerosol-induced attenuation of parenchymal T cell proliferation was also observed in BALB/c mice immunized with OVA and in BALB/c mice following adoptive transfer of DO11.10 T cells bearing either a Th1 or Th2 phenotype. In mice that had received Th2 cells, the reduced proliferative responses were associated with a decrease in IL-2 expression but augmented IL-4 and IL-5 production. Invariably, the inhibition of proliferation was a consequence of the action of F4/80+ interstitial macrophages and did not involve alveolar macrophages or their products. These observations demonstrate that clonal expansion of T cells in the lung compartment is prevented following the onset of either Th1- or Th2-mediated inflammation. This form of immune regulation, which appears as a selective defect in IL-2-driven proliferation, may serve to prevent the development of chronic pulmonary lymphoproliferative responses.
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Carew M, Roberts K. Care of the patient with gout. Geriatr Nurs 1999; 20:156-7. [PMID: 10661106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
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178
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Kent-First M, Muallem A, Shultz J, Pryor J, Roberts K, Nolten W, Meisner L, Chandley A, Gouchy G, Jorgensen L, Havighurst T, Grosch J. Defining regions of the Y-chromosome responsible for male infertility and identification of a fourth AZF region (AZFd) by Y-chromosome microdeletion detection. Mol Reprod Dev 1999; 53:27-41. [PMID: 10230814 DOI: 10.1002/(sici)1098-2795(199905)53:1<27::aid-mrd4>3.0.co;2-w] [Citation(s) in RCA: 150] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Cytogenetic and molecular deletion analyses of azoospermic and oligozoospermic males have suggested the existence of AZoospermia Factor(s) (AZF) residing in deletion intervals 5 and 6 of the human Y-chromosome and coinciding with three functional regions associated with spermatogenic failure. Nonpolymorphic microdeletions in AZF are associated with a broad spectrum of testicular phenotypes. Unfortunately, Sequence Tagged Sites (STSs) employed in screening protocols range broadly in number and mapsite and may be polymorphic. To thoroughly analyze the AZF region(s) and any correlations that may be drawn between genotype and phenotype, we describe the design of nine multiplex PCR reactions derived from analysis of 136 loci. Each multiplex contains 4-8 STS primer pairs, amplifying a total of 48 Y-linked STSs. Each multiplex consists of one positive control: either SMCX or MIC2. We screened four populations of males with these STSs. Population I consisted of 278 patients diagnosed as having significant male factor infertility: either azoospermia, severe oligozoospermia associated with hypogonadism and spermatogenic arrest or normal sperm counts associated with abnormal sperm morphology. Population II consisted of 200 unselected infertile patients. Population III consisted of 36 patients who had previously been shown to have aneuploidy, cytological deletions or translocations involving the Y-chromosome or normal karyotypes associated with severe phenotype abnormalities. Population IV consisted of 920 fertile (control) males. The deletion rates in populations I, II and III were 20.5%, 7% and 58.3%, respectively. A total of 92 patients with deletions were detected. The deletion rate in population IV was 0.87% involving 8 fertile individuals and 4 STSs which were avoided in multiplex panel construction. The ability of the nine multiplexes to detect pathology associated microdeletions is equal to or greater than screening protocols used in other studies. Furthermore, the data suggest a fourth AZF region between AZFb and AZFc, which we have termed AZFd. Patients with microdeletions restricted to AZFd may present with mild oligozoospermia or even normal sperm counts associated with abnormal sperm morphology. Though a definitive genotype/phenotype correlation does not exist, large deletions spanning multiple AZF regions or microdeletions restricted to AZFa usually result in patients with Sertoli Cell Only (SCO) or severe oligozoospermia, whereas microdeletions restricted to AZFb or AZFc can result in patients with phenotypes which range from SCO to moderate oligozoospermia. The panel of nine multiplexed reactions, the Y-deletion Detection System (YDDS), provides a fast, efficient and accurate method of assessing the integrity of the Y-chromosome. To date, this study provides the most extensive screening of a proven fertile male population in tandem with 514 infertile males, derived from three different patient selection protocols.
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Mao CS, Berman N, Roberts K, Ipp E. Glucose entrainment of high-frequency plasma insulin oscillations in control and type 2 diabetic subjects. Diabetes 1999; 48:714-21. [PMID: 10102686 DOI: 10.2337/diabetes.48.4.714] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Regular high-frequency oscillations of insulin secretion are characteristic of normal beta-cell function. These oscillations are easily entrainable to an exogenous rhythm by small changes in glucose concentration in vitro. We tested whether high-frequency insulin oscillations in vivo would also be entrainable by glucose and whether a lack of entrainment would characterize the diabetic beta-cell. We tested 13 control subjects and 11 patients with type 2 diabetes. Subjects underwent serial blood sampling at 1-min intervals for 60-120 min in the basal state or with small (15 mg/kg) boluses of glucose injected intravenously at exact 29-min intervals. Time series analysis was carried out using spectral analysis. Oscillations of basal plasma glucose concentrations were observed in both control and type 2 diabetic subjects, with a mean period of 11.3 +/- 3.1 and 11.6 +/- 2.0 min, respectively. These oscillations were entrained to mean periods of 15.0 +/- 0.6 and 14.2 +/- 0.9 min, respectively, by exogenous glucose. Regular high-frequency insulin oscillations were observed in control subjects; the mean period of basal plasma insulin oscillations was 10.7 +/- 1.2 min and was entrained to exogenously injected glucose, with a period of 15.2 +/- 0.1 min. In contrast, in the type 2 diabetic subjects, spontaneous insulin oscillations were unchanged by the glucose rhythm; the mean periods were 10.0 +/- 1.0 min during the basal period, and 10.1 +/- 0.0 min during glucose injections. These results demonstrate that spontaneous high-frequency insulin oscillations can be successfully entrained by glucose in control subjects. However, these oscillations in type 2 diabetic subjects are not similarly entrained. We conclude that loss of entrainment of spontaneous high-frequency insulin oscillations in type 2 diabetes is a highly sensitive manifestation of beta-cell secretory dysfunction.
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Tunnicliffe WS, Fletcher TJ, Hammond K, Roberts K, Custovic A, Simpson A, Woodcock A, Ayres JG. Sensitivity and exposure to indoor allergens in adults with differing asthma severity. Eur Respir J 1999; 13:654-9. [PMID: 10232442 DOI: 10.1183/09031936.99.13365499] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
In asthma, it is uncertain whether there is an association between degrees of exposure to domestic allergens and asthma severity. The pattern of sensitivity and exposure to common indoor allergens was examined in subjects with differing asthma severity. Sensitivity to house dust mite, dog and cat allergen and exposure to Der p 1, Can f 1 and Fel d 1 were assessed by skin prick tests and settled dust analysis in 28 subjects with severe asthma and 28 age- and sex-matched subjects with mild asthma (two declined skin prick test). All severe asthmatic subjects had at least one positive skin test and 20 of the 28 subjects were positive to all three allergens. Fourteen of the 26 subjects with mild asthma who took skin prick tests were positive to at least one, and one of these subjects was positive to the three allergens tested. Except for bedroom Fel d 1, the proportion of severe asthmatics both sensitized and exposed to each allergen at each site was significantly greater than the proportion sensitized and exposed in the mild asthma group. The geometric mean allergen concentrations, with the exception of bedroom Fel d 1, were greater in sensitized severe asthmatics than the sensitized mild asthmatics, which was significant for Der p 1 in bedroom samples and Can f 1 in bedroom and living room samples. These results support an association between the degrees of domestic allergen exposure in sensitized individuals and asthma severity.
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Steurer W, Stadlmann S, Roberts K, Fischer M, Margreiter R, Gnaiger E. Quality assessment of isolated pancreatic rat islets by high-resolution respirometry. Transplant Proc 1999; 31:650. [PMID: 10083280 DOI: 10.1016/s0041-1345(98)01600-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Roberts K, Fagan C, Foti K, Jung B, Kovatcheva S, Machacek L. Tackling Youth Unemployment in East-Central Europe. JOURNAL OF EAST EUROPEAN MANAGEMENT STUDIES 1999. [DOI: 10.5771/0949-6181-1999-3-238] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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184
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Jaffar Z, Roberts K, Pandit A, Linsley P, Djukanovic R, Holgate S. B7 costimulation is required for IL-5 and IL-13 secretion by bronchial biopsy tissue of atopic asthmatic subjects in response to allergen stimulation. Am J Respir Cell Mol Biol 1999; 20:153-62. [PMID: 9870929 DOI: 10.1165/ajrcmb.20.1.3255] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Asthma is a complex disorder characterized by airway hyperreactivity and inflammation. To analyze cellular interactions required for the secretion of cytokines by the bronchial mucosa, we have evaluated the ex vivo response of tissue explants to allergen. Endobronchial mucosal biopsy tissue from mild atopic asthmatic subjects and normal control subjects were maintained in culture for 24 h. To detect reactivity to allergen, the explants were stimulated with dust mite extract Dermatophagoides pteronyssinus (Der p). Our analysis revealed that without any overt stimulation, mRNA transcripts for interleukin (IL)-5 and IL-13 were expressed by asthmatic but not normal bronchial tissue. In contrast, the expression of interferon-gamma was observed in a higher proportion of cultured bronchial biopsies from the normal control subjects than in those from asthmatic subjects. Addition of Der p allergen did not change the cytokine profile of the explants from control volunteers but augmented the expression of IL-5 mRNA and induced secretion of the protein by the asthmatic bronchial tissue. In most cases, allergen also increased the production of IL-13 by bronchial tissue from asthmatic subjects. The allergen-induced secretion of IL-5 and IL-13 was inhibited by the fusion protein CTLA-4Ig, reflecting a requirement for CD80 (B7-1) and/or CD86 (B7-2) costimulation for the expression of the Th2 cytokines. This requirement for B7/CD28 costimulation is consistent with the hypothesis that IL-5 and IL-13 are produced by allergen-specific T cells resident in the asthmatic bronchial mucosa.
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Nath R, Roberts K, Ng M, Peschel R, Chen Z. Correlation of medical dosimetry quality indicators to the local tumor control in patients with prostate cancer treated with iodine-125 interstitial implants. Med Phys 1998; 25:2293-307. [PMID: 9874821 DOI: 10.1118/1.598440] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
The treatment of prostate cancer by 125I interstitial implants has been extensively studied with mixed results by one institution or another. A recent study from Hahnemann [Int. J. Radiat. Oncol., Biol., Phys. 21,955-960 (1991)] reported results that were extremely poor compared to those reported in an earlier study at Yale [Int. J. Radiat. Oncol., Biol., Phys. 14, 1153-1157 (1988)] or those in an Eastern Virginia Study [Cancer 63, 2415-2420 (1989)]; differences in 5-yr survival rates being more than a factor of 2. Such large discrepancies from institution to institution led us to a reexamination of the dosimetry. This study analyzed quantitatively three-dimensional dosimetric parameters of 110 prostate cancer patients treated with 125I interstitial implants. The study searched for "cutoff" values in each parameter that divided the patients into two groups with statistically significant differences in the local recurrence-free survival rates. A comparison of the three-dimensional isodose surfaces of patients with favorable values in all of the parameters to those patients with all unfavorable parameters show how these characteristics translated into poor dose coverage and much inhomogeneity within the implant even for cases that met the traditional criteria for adequacy (160 Gy to the tumor volume). Patients in the favorable group had 10-yr survival rates higher by a factor of up to 2 compared to those in the unfavorable group. The strong correlation of three-dimensional volume-dose parameters to the local control rate observed in this study further emphasizes how important it is to assess the three-dimensional dosimetric adequacy of interstitial implants before deciding on their clinical efficacy. If implants are performed with appropriate attention to dosimetry parameters, excellent clinical results are obtained. On the other hand, if dosimetry parameters are not correct, the implant results can be poor.
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Hogg L, Roberts K. Temporal arteritis. Geriatr Nurs 1998; 19:336-7. [PMID: 9919119 DOI: 10.1016/s0197-4572(98)90122-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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187
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Tamagnone L, Merida A, Stacey N, Plaskitt K, Parr A, Chang CF, Lynn D, Dow JM, Roberts K, Martin C. Inhibition of phenolic acid metabolism results in precocious cell death and altered cell morphology in leaves of transgenic tobacco plants. THE PLANT CELL 1998; 10:1801-16. [PMID: 9811790 PMCID: PMC143962 DOI: 10.1105/tpc.10.11.1801] [Citation(s) in RCA: 117] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Several complex phenotypic changes are induced when the transcription factor AmMYB308 is overexpressed in transgenic tobacco plants. We have previously shown that the primary effect of this transcription factor is to inhibit phenolic acid metabolism. In the plants that we produced, two morphological features were prominent: abnormal leaf palisade development and induction of premature cell death in mature leaves. Evidence from the analysis of these transgenic plants suggests that both changes resulted from the lack of phenolic intermediates. These results emphasize the importance of phenolic secondary metabolites in the normal growth and development of tobacco. We suggest that phenolic acid derivatives are important signaling molecules in the final stages of leaf palisade formation and that phenolic acid derivatives also play a prominent role in tissue senescence.
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Tamagnone L, Merida A, Stacey N, Plaskitt K, Parr A, Chang CF, Lynn D, Dow JM, Roberts K, Martin C. Inhibition of phenolic acid metabolism results in precocious cell death and altered cell morphology in leaves of transgenic tobacco plants. THE PLANT CELL 1998; 10:1801-1816. [PMID: 9811790 DOI: 10.2307/3870905] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Several complex phenotypic changes are induced when the transcription factor AmMYB308 is overexpressed in transgenic tobacco plants. We have previously shown that the primary effect of this transcription factor is to inhibit phenolic acid metabolism. In the plants that we produced, two morphological features were prominent: abnormal leaf palisade development and induction of premature cell death in mature leaves. Evidence from the analysis of these transgenic plants suggests that both changes resulted from the lack of phenolic intermediates. These results emphasize the importance of phenolic secondary metabolites in the normal growth and development of tobacco. We suggest that phenolic acid derivatives are important signaling molecules in the final stages of leaf palisade formation and that phenolic acid derivatives also play a prominent role in tissue senescence.
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189
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Sakawi Y, Groudine S, Roberts K, Chang B, Shah D, Lumb P. Carotid endarterectomy surgery and ICU admissions: a regional anesthesia perspective. J Neurosurg Anesthesiol 1998; 10:211-7. [PMID: 9796604 DOI: 10.1097/00008506-199810000-00002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Stroke is a major cause of mortality and morbidity in the United States. This study was performed to determine whether the authors' practice of monitoring the majority of patients in the postanesthesia care unit for 2 hours, selectively admitting the recovering carotid endarterectomy patients to the intensive care unit when feasible, and using regional anesthesia for the majority of cases, resulted in adverse outcomes or compromised the safety of the operation at a tertiary care academic medical center. The records of 337 patients (a total of 420 procedures) who underwent carotid endatertectomy surgery without concurrent heart surgery during a consecutive 18-month period ending in June, 1995 were reviewed. Regional anesthesia was the technique used in 97% of the procedures. Shunt placement was deemed necessary in 7% of the procedures. Postoperative strokes occurred in approximately 1% of patients. No shunted patients had a postoperative stroke. The rate of admission to intensive care units was 4%. Blood pressure control accounted for 73% of the patients admitted to intensive care units. Most patients required 2 hours of monitoring in the postanesthesia care unit before triage to the appropriate level of postoperative care. These results suggest that a monitoring period of 2 hours in the postanesthesia care unit allows for safe assessment of the postoperative carotid endarterectomy patient, and that routine intensive care unit admission after carotid endarterectomy surgery is not necessary.
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190
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Roberts K. Patchwork and quilting as holistic health practice. THE AUSTRALIAN JOURNAL OF HOLISTIC NURSING 1998; 5:4-6. [PMID: 10428887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Patchwork and quilting can be part of holistic care to clients and their loved ones. Nurses can encourage clients to use these skills to promote health and divert their attention from their illness. They can also encourage clients' loved ones to make commemorative quilts. Such strategies will help to enhance the emotional and spiritual side of nursing.
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Fraser CM, Norris SJ, Weinstock GM, White O, Sutton GG, Dodson R, Gwinn M, Hickey EK, Clayton R, Ketchum KA, Sodergren E, Hardham JM, McLeod MP, Salzberg S, Peterson J, Khalak H, Richardson D, Howell JK, Chidambaram M, Utterback T, McDonald L, Artiach P, Bowman C, Cotton MD, Fujii C, Garland S, Hatch B, Horst K, Roberts K, Sandusky M, Weidman J, Smith HO, Venter JC. Complete genome sequence of Treponema pallidum, the syphilis spirochete. Science 1998; 281:375-88. [PMID: 9665876 DOI: 10.1126/science.281.5375.375] [Citation(s) in RCA: 697] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The complete genome sequence of Treponema pallidum was determined and shown to be 1,138,006 base pairs containing 1041 predicted coding sequences (open reading frames). Systems for DNA replication, transcription, translation, and repair are intact, but catabolic and biosynthetic activities are minimized. The number of identifiable transporters is small, and no phosphoenolpyruvate:phosphotransferase carbohydrate transporters were found. Potential virulence factors include a family of 12 potential membrane proteins and several putative hemolysins. Comparison of the T. pallidum genome sequence with that of another pathogenic spirochete, Borrelia burgdorferi, the agent of Lyme disease, identified unique and common genes and substantiates the considerable diversity observed among pathogenic spirochetes.
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Femenia A, Garosi P, Roberts K, Waldron KW, Selvendran RR, Robertson JA. Tissue-related changes in methyl-esterification of pectic polysaccharides in cauliflower (Brassica oleracea L. var. botrytis) stems. PLANTA 1998; 205:438-444. [PMID: 9640669 DOI: 10.1007/s004250050341] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Pectic substances are a major component of cell walls in vegetable plants and have an important influence on plant food texture. Cauliflower (Brassica oleracea L. var. botrytis) stem sections at different regions of the mature plant stem have been monitored for tissue-related changes in the native pectic polysaccharides. Chemical analysis detected appreciable differences in the degree of methyl-esterification (ME) of pectic polysaccharides. About 65% of galacturonic acid (GalpA) residues were methyl-esterified in floret tissues. Relative ME showed a basipetal decrease, from 94% in the upper stem to 51% in the lower-stem vascular tissues. The decrease was not related to a basipetal increase in glucuronic acid (GlcpA) residues. The monoclonal antibodies, JIM 5 and JIM 7, produced distinct labelling patterns for the relatively low-methylesterified and high-methyl-esterified pectin epitopes, respectively. Labelling was related to cell type and tissue location in the stem. Floret cell walls contained epitopes for both JIM 5 and JIM 7 throughout the wall. Stem vascular tissues labelled more strongly with JIM 5. Whereas pith parenchyma in the upper stem labelled more strongly with JIM 7, in the lower-stem pith parenchyma, JIM 5 labelling predominated. Localization of pectic polysaccharide epitopes in cell walls provides an insight into how structural modifications might relate to the textural and nutritional properties of cell walls.
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Schneider K, Mathur J, Boudonck K, Wells B, Dolan L, Roberts K. The ROOT HAIRLESS 1 gene encodes a nuclear protein required for root hair initiation in Arabidopsis. Genes Dev 1998; 12:2013-21. [PMID: 9649505 PMCID: PMC316963 DOI: 10.1101/gad.12.13.2013] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The epidermis of Arabidopsis wild-type primary roots, in which some cells grow hairs and others remain hairless in a position-dependent manner, has become an established model system to study cell differentiation. Here we present a molecular analysis of the RHL1 (ROOT HAIRLESS 1) gene that, if mutated, prevents the formation of hairs on primary roots and causes a seedling lethal phenotype. We have cloned the RHL1 gene by use of a T-DNA-tagged mutant and found that it encodes a protein that appears to be plant specific. The predicted RHL1 gene product is a small hydrophilic protein (38.9 kD) containing putative nuclear localization signals and shows no significant homology to any known amino acid sequence. We demonstrate that a 78-amino-acid sequence at its amino terminus is capable of directing an RHL1-GFP fusion protein to the nucleus. The RHL1 transcript is present throughout the wild-type plant and in suspension culture cells, but in very low amounts, suggesting a regulatory function for the RHL1 protein. Structural evidence suggests a role for the RHL1 gene product in the nucleolus. We have examined the genetic relationship between RHL1 and GL2, an inhibitor of root hair initiation in non-hair cells. Our molecular and genetic data with double mutants, together with the expression analysis of a GL2 promoter-GUS reporter gene construct, indicate that the RHL1 gene acts independently of GL2.
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194
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Biddle J, Roberts K, Rosenman KD, Welch EM. What percentage of workers with work-related illnesses receive workers' compensation benefits? J Occup Environ Med 1998; 40:325-31. [PMID: 9571523 DOI: 10.1097/00043764-199804000-00006] [Citation(s) in RCA: 126] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
This study estimates the rate at which workers suffering from occupational illnesses file for workers' compensation lost wage benefits and identifies some of the factors that affect the probability that a worker with an occupational illness will file. A database of reports of known or suspected cases of occupational illness is matched with workers' compensation claims data. Overall, between 9% and 45% of reported workers file for benefits. Data limitations prevent a more precise estimate of this rate, but a large proportion of workers with occupational illnesses clearly does not utilize the worker's compensation system. Logit analysis of a choice-based sample shows that women and employees of small firms are more likely than others to file for worker's compensation and that filing rates vary considerably across industries and diagnostic categories. Acute conditions related to the current job are no more likely to lead to claims than chronic conditions with long latency periods between exposure and development of disease.
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Crawford AN, Boye U, Baggett J, Roberts K. The transfer of child patients from the community dental service to the general dental service. Br Dent J 1998; 184:134-6. [PMID: 9524375 DOI: 10.1038/sj.bdj.4809562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVE To determine an effective strategy for the transfer of children from the CDS to the GDS. DESIGN Single centre study comprising a retrospective analysis of a 50% random sample of dental records for children transferred from CDO to GDP. SETTING Community dental clinic in an urban area of south Manchester with relatively little material deprivation. SUBJECTS AND METHODS Between 1990 and 1995, a GDP worked up to 5 hours a week in the CDS clinic seeing routine child patients referred by the CDO. MAIN OUTCOME MEASURES Numbers of children registered with a GDP after varying periods of time. Attendance records of children transferred from CDS to GDS and rates of failed appointments. RESULTS After 4 1/2 years, 264 child patients had been registered with the GDP under capitation and a further 55 adults were registered under continuing care. The majority of children had retained registration for more than 2 1/2 years. The mean rate of failed appointments was 16%. CONCLUSION Children can be transferred successfully from the CDS to the GDS if the GDP works at the community clinic and there are further benefits which accrue to the scheme.
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Tamagnone L, Merida A, Parr A, Mackay S, Culianez-Macia FA, Roberts K, Martin C. The AmMYB308 and AmMYB330 transcription factors from antirrhinum regulate phenylpropanoid and lignin biosynthesis in transgenic tobacco. THE PLANT CELL 1998; 10:135-154. [PMID: 9490739 DOI: 10.2307/3870694] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
MYB-related transcription factors are known to regulate different branches of flavonoid metabolism in plants and are believed to play wider roles in the regulation of phenylpropanoid metabolism in general. Here, we demonstrate that overexpression of two MYB genes from Antirrhinum represses phenolic acid metabolism and lignin biosynthesis in transgenic tobacco plants. The inhibition of this branch of phenylpropanoid metabolism appears to be specific to AmMYB308 and AmMYB330, suggesting that they recognize their normal target genes in these transgenic plants. Experiments with yeast indicate that AmMYB308 can act as a very weak transcriptional activator so that overexpression may competitively inhibit the activity of stronger activators recognizing the same target motifs. The effects of the transcription factors on inhibition of phenolic acid metabolism resulted in complex modifications of the growth and development of the transgenic plants. The inhibition of monolignol production resulted in plants with at least 17% less lignin in their vascular tissue. This reduction is of importance when designing strategies for the genetic modification of woody crops.
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197
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Tamagnone L, Merida A, Parr A, Mackay S, Culianez-Macia FA, Roberts K, Martin C. The AmMYB308 and AmMYB330 transcription factors from antirrhinum regulate phenylpropanoid and lignin biosynthesis in transgenic tobacco. THE PLANT CELL 1998; 10:135-54. [PMID: 9490739 PMCID: PMC143979 DOI: 10.1105/tpc.10.2.135] [Citation(s) in RCA: 334] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
MYB-related transcription factors are known to regulate different branches of flavonoid metabolism in plants and are believed to play wider roles in the regulation of phenylpropanoid metabolism in general. Here, we demonstrate that overexpression of two MYB genes from Antirrhinum represses phenolic acid metabolism and lignin biosynthesis in transgenic tobacco plants. The inhibition of this branch of phenylpropanoid metabolism appears to be specific to AmMYB308 and AmMYB330, suggesting that they recognize their normal target genes in these transgenic plants. Experiments with yeast indicate that AmMYB308 can act as a very weak transcriptional activator so that overexpression may competitively inhibit the activity of stronger activators recognizing the same target motifs. The effects of the transcription factors on inhibition of phenolic acid metabolism resulted in complex modifications of the growth and development of the transgenic plants. The inhibition of monolignol production resulted in plants with at least 17% less lignin in their vascular tissue. This reduction is of importance when designing strategies for the genetic modification of woody crops.
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Domingo C, Roberts K, Stacey NJ, Connerton I, Ruíz-Teran F, McCann MC. A pectate lyase from Zinnia elegans is auxin inducible. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 1998; 13:17-28. [PMID: 9680962 DOI: 10.1046/j.1365-313x.1998.00002.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The Zinnia mesophyll cell system consists of isolated leaf mesophyll cells in culture that can be induced, by auxin and cytokinin, to reproducibly trans-differentiate into tracheary elements (TE) after 96 h, while in the presence of auxin alone the cells simply elongate. In a search for genes involved in modifications to cell-wall architecture before any overt signs of cell differentiation, a differential hybridization of a 72-h cDNA library with probes from mRNA at time-points of 24 h and 72 h was done revealing a number of transcripts up-regulated between these times. One of these cDNAs shows homology to pectate lyase, a pectin-degrading enzyme. The complete cDNA sequence (ZePel) corresponds to a translated protein of 44 kDa with an N-terminal signal peptide of about 2 kDa, and one potential N-glycosylation site. Northern analysis confirms that the strong expression of this gene during TE induction occurs at a very early stage of the process and is due solely to the presence of auxin in the induction medium. In situ hybridization studies in young Zinnia stems show that ZePel expression is associated with vascular bundles and shoot primordia. Recombinant protein made in Escherichia coli possesses calcium-dependent pectate lyase activity. Pectate lyase activity is detected in elongating and differentiating in vitro cell populations. The role of this enzyme in remodelling the cell wall during cell elongation and differentiation is discussed.
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Chung JY, Roberts K, Peschel RE, Nath R, Pourang R, Kacinski B, Wilson L. Treatment of recurrent pelvic and selected primary gynecologic malignancies with 241Am. RADIATION ONCOLOGY INVESTIGATIONS 1997; 5:227-34. [PMID: 9372545 DOI: 10.1002/(sici)1520-6823(1997)5:5<227::aid-roi3>3.0.co;2-#] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The purpose of this study was to update the experience and demonstrate the effectiveness and limitations of 241Am applicators for previously irradiated patients and for selected patients with primary gynecologic malignancies. Between October 1986 and May 1994, 30 patients were treated with 241Am. The median patient age was 68 years, ranging from 41 to 91 years. Patients were retrospectively categorized by treatment intent, i.e., palliative vs. curative. Patients undergoing curative therapy were further classified as to whether 241Am brachytherapy was directed at microscopic residua after surgery or to gross primary tumor. Of the 30 patients, 18 had recurrent pelvic malignancies from various primary sites and were reirradiated with 241Am for palliation. Six patients had microscopic disease after surgical resection and were managed with postoperative radiotherapy (RT) that included 241Am. Six patients had gynecologic cancers managed with primary RT that included treatment with 241Am. Overall, 50% (9/18) of the patients with recurrent pelvic malignancies were locally controlled after reirradiation with 241Am. Including surgical salvage, the ultimate local control rate was 61% (11/18). Postoperative 241Am with or without external beam radiation therapy (XRT) was effective in 83% (5/6) of the patients with microscopic disease. Including surgical salvage, 100% (6/6) of the patients were ultimately free of disease. Fifty percent (3/6) of the patients treated with primary RT that included 241Am brachytherapy experienced local control. Including surgical salvage, 67% (4/6) of the patients were ultimately controlled with 241Am. In conclusion, reirradiation utilizing 241Am was effective in palliating patients with recurrent pelvic malignancies. 241Am was effective in 83% (5/6) of the patients with microscopic disease managed with postoperative RT. 241Am was of marginal benefit in patients with gynecologic tumors managed with primary RT.
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Grossberg S, Roberts K, Aguilar M, Bullock D. A neural model of multimodal adaptive saccadic eye movement control by superior colliculus. J Neurosci 1997; 17:9706-25. [PMID: 9391024 PMCID: PMC6573406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/1997] [Revised: 09/23/1997] [Accepted: 09/25/1997] [Indexed: 02/05/2023] Open
Abstract
How does the saccadic movement system select a target when visual, auditory, and planned movement commands differ? How do retinal, head-centered, and motor error coordinates interact during the selection process? Recent data on superior colliculus (SC) reveal a spreading wave of activation across buildup cells the peak activity of which covaries with the current gaze error. In contrast, the locus of peak activity remains constant at burst cells, whereas their activity level decays with residual gaze error. A neural model answers these questions and simulates burst and buildup responses in visual, overlap, memory, and gap tasks. The model also simulates data on multimodal enhancement and suppression of activity in the deeper SC layers and suggests a functional role for NMDA receptors in this region. In particular, the model suggests how auditory and planned saccadic target positions become aligned and compete with visually reactive target positions to select a movement command. For this to occur, a transformation between auditory and planned head-centered representations and a retinotopic target representation is learned. Burst cells in the model generate teaching signals to the spreading wave layer. Spreading waves are produced by corollary discharges that render planned and visually reactive targets dimensionally consistent and enable them to compete for attention to generate a movement command in motor error coordinates. The attentional selection process also helps to stabilize the map-learning process. The model functionally interprets cells in the superior colliculus, frontal eye field, parietal cortex, mesencephalic reticular formation, paramedian pontine reticular formation, and substantia nigra pars reticulata.
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