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Rubiño M, Cruz A, Garcia JA, Hita E. Discomfort glare indices: a comparative study. APPLIED OPTICS 1994; 33:8001-8008. [PMID: 20963016 DOI: 10.1364/ao.33.008001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
From the luminance distribution measured with a stereoluminancemeter we have studied the variation in the principal indices of discomfort glare while considering the orientation of the line of vision of the observer and the limiting luminance of the glare source. This method provides the ideal orientation for the observer in a lighted environment, minimizes the detrimental effects of glare, and determines the reliability of the indices calculated for discomfort glare.
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Martínez ME, del Campo MT, Sánchez-Cabezudo MJ, Garcia JA, Sánchez Calvín MT, Torrijos A, Coya J, Munuera L. Relations between calcidiol serum levels and bone mineral density in postmenopausal women with low bone density. Calcif Tissue Int 1994; 55:253-6. [PMID: 7820775 DOI: 10.1007/bf00310401] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The relationship between vitamin D and bone density was studied in 150 selected, mature (45-74), postmenopausal women with a lumbar spine Z score below 0. Vitamin D status was evaluated using calcidiol serum levels. Serum calcitriol and parathyroid hormone (PTH) values were also evaluated in some subjects. Bone mass was evaluated by ascertaining bone density and Z and T scores in the lumbar spine and femur region. The reference group consisted of 25 premenopausal women. The postmenopausal group was divided into subgroups according to age, i.e., under or over 60 years old. Additionally, the whole group was also subdivided according to their lumbar spine Z scores into group I (Z > -1), group II (Z < -1; > -2), and group III (Z < -2). Group III of postmenopausal women had higher PTH and lower calcitriol levels than premenopausal women. Calcidiol serum levels were lower in postmenopausal women groups II or III than in the group I and premenopausal women. Calcidiol serum levels and the bone mass values for the lumbar spine were correlated positively in all the postmenopausal women; in the women over 60 years of age, calcidiol levels also correlated with the bone mass values expressed as the bone density in three femur regions: femoral neck, trocanter, and Ward's triangle. In conclusion, mature post-menopausal woman showed high PTH levels and low calcidiol and calcitriol values. Calcidiol status is significantly related to bone mineral density in the lumbar spine and in women over 60 years, calcidiol levels also correlated with bone density in the femur regions.
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Martins CA, Velasco ED, Garcia JA, Caetano R. [Poisoning caused by external use of iodoform]. REVISTA DO HOSPITAL DAS CLINICAS 1994; 49:177-8. [PMID: 7871328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A case of iodoform toxicity caused by use of 5% iodoformed bandage in occlusive surgical dressings for tamponing of diffuse hemorrhage in pelvic cavity, following amputation for treatment of rectum adenocarcinoma. Despite the frequent use of iodoformed dressings following surgical procedures, the signs and symptoms of iodoform toxicity syndrome can be easily mistook for other syndromes. A revision of the published observations suggest that this syndrome is not as rare as thought but probably has been underdiagnosed.
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McMinn SB, Garcia JA, Zuckerman JH, Levine BD. 716 THE RIGHT VENTRICLE DURING EXERCISE AT HIGH ALTITUDE. Med Sci Sports Exerc 1994. [DOI: 10.1249/00005768-199405001-00718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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55
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Abstract
Gastric volvulus and wandering spleen are related to anomalies in the intraperitoneal visceral attachments. When encountered during infancy, they have a congenital origin with acquired predisposing factors. Wandering spleen is a rare clinical entity with a diverse form of presentation. To our knowledge, gastric volvulus associated with wandering spleen has not been reported previously in literature.
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Garcia JA, Gaynor RB. The human immunodeficiency virus type-1 long terminal repeat and its role in gene expression. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 1994; 49:157-96. [PMID: 7863006 DOI: 10.1016/s0079-6603(08)60050-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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57
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Herzberg AJ, Garcia JA, Kerns BJ, Jordan PA, Pence JC, Rotter SM, Dzubow LM. DNA ploidy of basal cell carcinoma determined by image cytometry of fresh smears. J Cutan Pathol 1993; 20:216-22. [PMID: 8366211 DOI: 10.1111/j.1600-0560.1993.tb00646.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Image analysis of nuclear DNA content (DNA ploidy) was performed on smears of basal cell carcinoma (BCC) obtained during Mohs microscopically-controlled surgery from 51 tumors. DNA ploidy was compared with histologic growth pattern and the contour of the invading edge. There was a statistically significantly increased frequency of DNA aneuploidy in smears from BCC exhibiting partial or total diffuse (infiltrative and superficial multicentric) growth patterns (80%; 32 of 40) as compared to solely circumscribed growth patterns (0%; 0 of 11) (p < 0.001).
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58
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Wolf HK, Garcia JA, Bossen EH. Oncocytic differentiation in intrahepatic biliary cystadenocarcinoma. Mod Pathol 1992; 5:665-8. [PMID: 1369804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/25/2023]
Abstract
An intrahepatic biliary cystadenocarcinoma in a 56-yr-old white man was characterized by pronounced oncocytic differentiation. Grossly the tumor was a well-demarcated cyst filled with numerous branching papillary fronds. Most tumor cells had abundant granular, intensely eosinophilic cytoplasm on light microscopic examination and large numbers of densely packed mitochondria by electron microscopy. Mucin-secreting cells were also present. The patient returned 20 mo after resection of the primary tumor with recurrent tumor in the liver and widely disseminated disease throughout the abdominal cavity, and he died 5 mo later. Although less differentiated, the recurrent tumor again contained greatly increased numbers of mitochondria. The partial loss of oncocytic differentiation in the evolution of the present case and the benign nature of purely oncocytic tumors suggest that in the presence of mixed histologic features the potential for tumor progression is primarily determined by the lesser differentiated or nononcocytic component. To the best of our knowledge, oncocytic differentiation has not been previously described in biliary neoplasia.
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Garcia JA, Ou SH, Wu F, Lusis AJ, Sparkes RS, Gaynor RB. Cloning and chromosomal mapping of a human immunodeficiency virus 1 "TATA" element modulatory factor. Proc Natl Acad Sci U S A 1992; 89:9372-6. [PMID: 1409643 PMCID: PMC50133 DOI: 10.1073/pnas.89.20.9372] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
A critical regulatory element in many promoters transcribed by RNA polymerase II is the "TATA" box, which is located 25-30 nucleotides upstream of the transcription initiation site. TFIID is a biochemically defined HeLa cell nuclear fraction containing a transcription factor activity that binds specifically to the TATA box and is critical in determining both basal and regulated promoter activity. Recently, the gene for a TATA-binding protein was cloned and found to bind to various TATA elements and to substitute for TFIID in stimulating basal gene expression in in vitro transcription systems. However, it is possible that additional cellular factors can bind to the TATA element and influence the level of gene expression. By using lambda gt11 expression cloning with oligonucleotides corresponding to the human immunodeficiency virus 1 TATA element, we report the identification of a cellular protein with a calculated molecular mass of 123 kDa that we designate TATA element modulatory factor (TMF). TMF binds to the human immunodeficiency virus 1 TATA element in gel-retardation assays and inhibits activation of the viral long terminal repeat by the TATA-binding protein in in vitro transcription assays. TMF contains leucine-zipper amino acid motifs and exhibits homology in its DNA binding domain with the phage-encoded DNA binding protein Ner. Chromosomal mapping localizes the TMF gene to human chromosome 3p12-p21, which is a site of frequent rearrangements in lung and renal carcinomas. Thus, TMF is a transcription factor that likely regulates the expression of both viral and cellular genes.
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Garcia JA, Romero J, Barco LJ, Hita E. Improved formula for evaluating color-differential thresholds. APPLIED OPTICS 1992; 31:6292-6298. [PMID: 20733843 DOI: 10.1364/ao.31.006292] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
A new group of color-difference formulas is proposed that gives better results than the previous formulas supplied by Romero et al. [Appl. Opt. 28, 4697-4702 (1989)]. The new formulas are deduced from chromatic discrimination data and behave more consistently at the boundaries between regions of similar hue in the CIE-1931 diagram. They also fit well with experimental color-difference data.
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Myers SA, Prose NS, Garcia JA, Wilson KH, Dunsmore KP, Kamino H. Bacillary angiomatosis in a child undergoing chemotherapy. J Pediatr 1992; 121:574-8. [PMID: 1403392 DOI: 10.1016/s0022-3476(05)81148-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Bacillary angiomatosis is an infectious disease of the skin and viscera characterized by vascular lesions, originally described in patients with human immunodeficiency virus infection. There are also case reports of bacillary angiomatosis occurring in immunocompetent patients and in noninfected patients with suppressed immune function. We report a case of bacillary angiomatosis in a child undergoing chemotherapy for acute leukemia.
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Fernandez-Garayzabal JF, Blanco M, Vazquez-Boland JA, Briones V, Garcia JA, Delgado C, Domingo M, Marco J, Dominguez L. A direct plating method for monitoring the contamination of Listeria monocytogenes in silage. ZENTRALBLATT FUR VETERINARMEDIZIN. REIHE B. JOURNAL OF VETERINARY MEDICINE. SERIES B 1992; 39:513-8. [PMID: 1455943 DOI: 10.1111/j.1439-0450.1992.tb01200.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Twenty-two silage samples were analyzed for the presence of L. monocytogenes using five Listeria selective plating media, with and without previous selective enrichment step. L. monocytogenes was recovered from 3 samples by both procedures, but direct plating allowed the quantification of Listeria population. Two of these positive samples were implicated in outbreaks of listeriosis in sheep; the L. monocytogenes population in these samples was about 10(6) cells/g. The L. monocytogenes population in the other positive sample was 10(3) cells/g. Direct isolation of L. monocytogenes was only possible from LPM, PALCAM and LSAMm media. MOX and LSM media were not selective enough to allow direct Listeria isolation. In our hands, LSAMm was the most suitable plating medium for the direct isolation and specific quantification of L. monocytogenes from silage employing a red blood cells overlay technique.
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Spiro RC, Freeze HH, Sampath D, Garcia JA. Uncoupling of chondroitin sulfate glycosaminoglycan synthesis by brefeldin A. J Cell Biol 1991; 115:1463-73. [PMID: 1955486 PMCID: PMC2289244 DOI: 10.1083/jcb.115.5.1463] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Brefeldin A has dramatic, well-documented, effects on the structural and functional organization of the Golgi complex. We have examined the effects of brefeldin A (BFA) on the Golgi-localized synthesis and addition of chondroitin sulfate glycosaminoglycan carbohydrate side chains. BFA caused a dose-dependent inhibition of chondroitin sulfate glycosaminoglycan elongation and sulfation onto the core proteins of the melanoma-associated proteoglycan and the major histocompatibility complex class II-associated invariant chain. In the presence of BFA, the melanoma proteoglycan core protein was retained in the ER but still acquired complex, sialylated, N-linked oligosaccharides, as measured by digestion with endoglycosidase H and neuraminidase. The initiation of glycosaminoglycan synthesis was not affected by BFA, as shown by the incorporation of [6-3H]galactose into a protein-carbohydrate linkage region that was sensitive to beta-elimination. The ability of cells to use an exogenous acceptor, p-nitrophenyl-beta-D-xyloside, to elongate and sulfate core protein-free glycosaminoglycans, was completely inhibited by BFA. The effects of BFA were completely reversible in the absence of new protein synthesis. These experiments indicate that BFA effectively uncouples chondroitin sulfate glycosaminoglycan synthesis by segregating initiation reactions from elongation and sulfation events. Our findings support the proposal that glycosaminoglycan elongation and sulfation reactions are associated with the trans-Golgi network, a BFA-resistant, Golgi subcompartment.
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Araújo CM, Souhami L, Gil RA, Carvalho R, Garcia JA, Froimtchuk MJ, Pinto LH, Canary PC. A randomized trial comparing radiation therapy versus concomitant radiation therapy and chemotherapy in carcinoma of the thoracic esophagus. Cancer 1991. [PMID: 1707338 DOI: 10.1002/1097-0142(19910501)67:9<2258::aid-cncr2820670908>3.0.co;2-g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
From September 1982 to December 1985, 59 previously untreated patients with Stage II squamous cell carcinoma of the thoracic esophagus were randomly assigned to receive radiation therapy (RT) alone versus the concomitant use of RT and chemotherapy (CT) with 5-fluorouracil (5-FU), mitomycin C, and bleomycin (RT + CT). Thirty-one patients were randomized to the RT regimen and 28 to the RT + CT regimen. The complete local response rate was 58% for the RT group and 75% for the RT + CT group (P = 0.77). The median duration of response was 8 months for both groups. The overall 5-year survival rates were 6% and 16% (P = 0.16) for the RT and RT + CT groups, respectively. Acute toxicities were more pronounced in the RT + CT group. This clinical trial did not detect a difference in outcome with combined-technique therapy. This result must be interpreted with caution because of the small number of patients entered in this trial. Confirmation of the value or lack of value for combined therapy will require additional larger clinical trials.
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Araújo CM, Souhami L, Gil RA, Carvalho R, Garcia JA, Froimtchuk MJ, Pinto LH, Canary PC. A randomized trial comparing radiation therapy versus concomitant radiation therapy and chemotherapy in carcinoma of the thoracic esophagus. Cancer 1991; 67:2258-61. [PMID: 1707338 DOI: 10.1002/1097-0142(19910501)67:9<2258::aid-cncr2820670908>3.0.co;2-g] [Citation(s) in RCA: 162] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
From September 1982 to December 1985, 59 previously untreated patients with Stage II squamous cell carcinoma of the thoracic esophagus were randomly assigned to receive radiation therapy (RT) alone versus the concomitant use of RT and chemotherapy (CT) with 5-fluorouracil (5-FU), mitomycin C, and bleomycin (RT + CT). Thirty-one patients were randomized to the RT regimen and 28 to the RT + CT regimen. The complete local response rate was 58% for the RT group and 75% for the RT + CT group (P = 0.77). The median duration of response was 8 months for both groups. The overall 5-year survival rates were 6% and 16% (P = 0.16) for the RT and RT + CT groups, respectively. Acute toxicities were more pronounced in the RT + CT group. This clinical trial did not detect a difference in outcome with combined-technique therapy. This result must be interpreted with caution because of the small number of patients entered in this trial. Confirmation of the value or lack of value for combined therapy will require additional larger clinical trials.
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66
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Galindo MC, Campos MS, Garcia JA, Lisbona F. Influence of ouabain of electrolyte and water transport in the rabbit ileum and colon in vitro and in vivo. DIE NAHRUNG 1991; 35:577-80. [PMID: 1787845 DOI: 10.1002/food.19910350604] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
We studied the influence of the Na(+)-K+ pump inhibitor ouabain on water and electrolyte transport in the rabbit distal ileum and proximal colon in vitro and in vivo. Under in vitro conditions, ouabain markedly reduced the absorption of water, sodium, chloride and bicarbonate, and reduced potassium secretion in both the ileum and the colon. In vivo results were similar but less marked than those obtained in vitro, with significant differences only at the level of the distal ileum.
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Coves F, Lisbona F, Campos MS, Garcia JA, Lopez-Aliaga I, Barrionuevo M. Influence of intestinal resection and type of diet on the digestive and metabolic utilization of fats in rats. DIE NAHRUNG 1991; 35:503-11. [PMID: 1922277 DOI: 10.1002/food.19910350515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The effects of the quality of dietary fat, and the influence of ursodeoxycholic acid, an exogenous bile acid, on the digestive and metabolic utilization of fat were studied in rats in which 50% of the distal small intestine was resected. The fat content of the diets was quantitatively equivalent (4%), and differed only in the type of fat: olive oil (diet A) or 1/3 medium chain triglycerides (MCT), 1/3 sunflower oil and 1/3 olive oil (diet B). The removal of 50% of the distal small intestine led to a highly significant decline in the digestive utilization of fat (ADC) in animals given diet A. Rats fed diet B showed an increase in ADC to values approaching those seen in control animals. The addition of ursodeoxycholic acid to diet B failed to cause a further rise in the ADC of fat. After intestinal resection, serum levels of triglycerides and cholesterol fell more markedly in animals given diet A than in the diet B group, while the addition of ursodeoxycholic acid to diet B led to no further change. Serum lipid levels showed no significant influence of intestinal resection, but did accurately reflect the differences in fat composition between the two types of diet tested.
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Garcia JA, Ingram CW, Granger D. Persistent neutrophilic meningitis due to Pseudallescheria boydii. REVIEWS OF INFECTIOUS DISEASES 1990; 12:959-60. [PMID: 2237138 DOI: 10.1093/clinids/12.5.959] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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69
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Wolf HK, Burchette JL, Garcia JA, Michalopoulos G. Exocrine pancreatic tissue in human liver: a metaplastic process? Am J Surg Pathol 1990; 14:590-5. [PMID: 2186646 DOI: 10.1097/00000478-199006000-00011] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Numerous microscopic foci of exocrine pancreatic tissue consisting of acini and small ductules were distributed throughout the liver of a 41-year-old patient with severe posthepatitic cirrhosis. The acinar cells were characterized by abundant zymogen granules on electron microscopic examination and a strong reaction with antibodies to alpha-amylase on immunoperoxidase staining. The pancreatic tissue was associated with proliferations of bile ductules within areas of fibrosis. No relationship with hepatocytes was observed. A metaplastic origin of the pancreatic tissue from the intrahepatic biliary epithelium is suggested.
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70
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Romero J, Garcia JA, Barco LJ, Hita E. Color difference formulas tested by use with chromatic discrimination data and new formulas. APPLIED OPTICS 1989; 28:4697-4702. [PMID: 20555934 DOI: 10.1364/ao.28.004697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
A set of five color difference formulas, cdf-G*, one for each of five regions of the CIE1931 chromatic diagram, is proposed and compared with the CIELUV, CIELAB, and LABNHU formulas. The cdf-G* formulas fit more closely several sets of color difference data. They are useful for color difference applications.
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Garcia JA, Harrich D, Soultanakis E, Wu F, Mitsuyasu R, Gaynor RB. Human immunodeficiency virus type 1 LTR TATA and TAR region sequences required for transcriptional regulation. EMBO J 1989; 8:765-78. [PMID: 2721501 PMCID: PMC400873 DOI: 10.1002/j.1460-2075.1989.tb03437.x] [Citation(s) in RCA: 163] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
The human immunodeficiency virus (HIV) type 1 LTR is regulated at the transcriptional level by both cellular and viral proteins. Using HeLa cell extracts, multiple regions of the HIV LTR were found to serve as binding sites for cellular proteins. An untranslated region binding protein UBP-1 has been purified and fractions containing this protein bind to both the TAR and TATA regions. To investigate the role of cellular proteins binding to both the TATA and TAR regions and their potential interaction with other HIV DNA binding proteins, oligonucleotide-directed mutagenesis of both these regions was performed followed by DNase I footprinting and transient expression assays. In the TATA region, two direct repeats TC/AAGC/AT/AGCTGC surround the TATA sequence. Mutagenesis of both of these direct repeats or of the TATA sequence interrupted binding over the TATA region on the coding strand, but only a mutation of the TATA sequence affected in vivo assays for tat-activation. In addition to TAR serving as the site of binding of cellular proteins, RNA transcribed from TAR is capable of forming a stable stem-loop structure. To determine the relative importance of DNA binding proteins as compared to secondary structure, oligonucleotide-directed mutations in the TAR region were studied. Local mutations that disrupted either the stem or loop structure were defective in gene expression. However, compensatory mutations which restored base pairing in the stem resulted in complete tat-activation. This indicated a significant role for the stem-loop structure in HIV gene expression. To determine the role of TAR binding proteins, mutations were constructed which extensively changed the primary structure of the TAR region, yet left stem base pairing, stem energy and the loop sequence intact. These mutations resulted in decreased protein binding to TAR DNA and defects in tat-activation, and revealed factor binding specifically to the loop DNA sequence. Further mutagenesis which inverted this stem and loop mutation relative to the HIV LTR mRNA start site resulted in even larger decreases in tat-activation. This suggests that multiple determinants, including protein binding, the loop sequence, and RNA or DNA secondary structure, are important in tat-activation and suggests that tat may interact with cellular proteins binding to DNA to increase HIV gene expression.
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Gonzalez JT, Atwood J, Garcia JA, Meyskens FL. Hispanics and cancer preventive behavior: the development of a behavioral model and its policy implications. JOURNAL OF HEALTH & SOCIAL POLICY 1988; 1:55-73. [PMID: 10304503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
This paper presents the theoretical development of a model that predicts the conditions under which Hispanics will seek preventive health care. Research trends, however, show that Hispanics tend to delay preventive care, resulting in higher morbidity and mortality rates for serious diseases such as cancer. Since many serious diseases, such as heart disease, diabetes and cancer can be prevented or treated more effectively if detected early, it is crucial to understand the motivating forces behind Hispanics' preventive health behavior. The Hispanic model, which is an extension of the Health Behavior in Cancer Prevention Model developed by Atwood (1986), includes as core variables environmental barriers to access and English language proficiency, as well as social support, health beliefs, self-efficacy, or perceived skill, health locus of control, and health values. The practical health policy applications of the model are also discussed.
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Gaynor RB, Kuwabara MD, Wu FK, Garcia JA, Harrich D, Briskin M, Wall R, Sigman DS. Repeated B motifs in the human immunodeficiency virus type I long terminal repeat enhancer region do not exhibit cooperative factor binding. Proc Natl Acad Sci U S A 1988; 85:9406-10. [PMID: 3200827 PMCID: PMC282761 DOI: 10.1073/pnas.85.24.9406] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The enhancer element of the human immunodeficiency virus type I (HIV-I) long terminal repeat (LTR) contains two copies of nearly identical sequences AGGGACTTTCC (3G sequence) and GGGGACTTTCC (4G sequence) that are important in transcriptional regulation. A single copy of the 4G sequence is found in the NF-kappa B site of the immunoglobulin kappa-chain enhancer. Only the 4G motif in the HIV enhancer is bound by cellular proteins in extracts prepared from unstimulated HeLa cells, whereas the 3G and 4G motifs are bound by factors in extracts prepared from HeLa cells treated with phorbol esters [phorbol 12-myristate 13-acetate (PMA)] and lymphoid cells. To determine if this change in binding to the HIV enhancer was due to phosphorylation of a cellular protein, partially purified PMA-treated HeLa nuclear extracts were digested with calf intestinal phosphatase. Phosphatase digestion of nuclear extracts from PMA-treated HeLa cells markedly decreased factor binding to the HIV enhancer. Accordingly, phosphorylation of the DNA binding protein itself, or an inhibitor protein present in the partially purified extract, must mediate binding to the recognition sequence. Binding studies confirmed that each of the enhancer sequences was capable of binding factors independent of the activity of the other site and that the HIV enhancer was occupied by only one factor at any one time. Chloramphenicol acetyltransferase assays using mutants in either one or both HIV enhancer repeats revealed that each site was capable of functioning as a tat-inducible enhancer element in PMA-treated HeLa cells. These results suggest that the 3G and 4G motifs in the HIV enhancer function independently and that duplication in the HIV enhancer augments activity by a mechanism distinct from cooperative binding of NF-kappa B.
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Garcia JA, Harrich D, Pearson L, Mitsuyasu R, Gaynor RB. Functional domains required for tat-induced transcriptional activation of the HIV-1 long terminal repeat. EMBO J 1988; 7:3143-7. [PMID: 3181132 PMCID: PMC454704 DOI: 10.1002/j.1460-2075.1988.tb03181.x] [Citation(s) in RCA: 121] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The transcriptional regulation of the human immunodeficiency virus (HIV) type I involves the interaction of both viral and cellular proteins. The viral protein tat is important in increasing the amount of viral steady-state mRNA and may also play a role in regulating the translational efficiency of viral mRNA. To identify distinct functional domains of tat, oligonucleotide-directed mutagenesis of the tat gene was performed. Point mutations of cysteine residues in three of the four Cys-X-X-Cys sequences in the tat protein resulted in a marked decrease in transcriptional activation of the HIV long terminal repeat. Point mutations which altered the basic C-domain of the protein also resulted in decreases in transcriptional activity, as did a series of mutations that repositioned either the N or C termini of the protein. Conservative mutations of other amino acids in the cysteine-rich or basic regions and in a series of proline residues in the N terminus of the molecule resulted in minimal changes in tat activation. These results suggest that several domains of tat protein are involved in transcriptional activation with the cysteine-rich domain being required for complete activity of the tat protein.
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Wu FK, Garcia JA, Harrich D, Gaynor RB. Purification of the human immunodeficiency virus type 1 enhancer and TAR binding proteins EBP-1 and UBP-1. EMBO J 1988; 7:2117-30. [PMID: 3138113 PMCID: PMC454507 DOI: 10.1002/j.1460-2075.1988.tb03051.x] [Citation(s) in RCA: 133] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Transcription of the human immunodeficiency virus type 1 (HIV-1) is regulated by viral proteins and cellular factors that bind to the viral long terminal repeat (LTR). At least five regions of the HIV LTR serve as binding sites for HeLa cellular proteins. One region containing two copies of the sequence GGGACTTTCC functions as an enhancer element for HIV transcriptional regulation. Another region between -17 and +44 known as the TAR region contains two copies of the sequence CTCTCTGG and is also important in tat-induced activation of the HIV LTR. HeLa cell extracts were used to purify cellular proteins binding to portions of the enhancer region (EBP-1) and the TAR region (UBP-1) by a combination of conventional and DNA affinity chromatography. Several species of proteins of between 55 and 60 kd were found to bind to specific sequences in the enhancer region and these proteins also bound to a portion of the NF-kappa B binding site in the immunoglobulin kappa enhancer. Two proteins of between 61 and 63 kd were the major species found to bind to specific sequences in the TAR region and fractions containing these proteins also bind to the TATA region. Both UBP-1 and EBP-1 exhibited specific binding as demonstrated by both UV cross-linking and DNase I footprinting. Mutations of either the enhancer or TAR regulatory regions prevented binding of these purified factors. These results demonstrate the binding of highly purified cellular proteins to important transcriptional regulatory regions in the HIV LTR.
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