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Sousa VL, Costa MT, Palma AS, Enguita F, Costa J. Localization, purification and specificity of the full-length membrane-bound form of human recombinant alpha 1,3/4-fucosyltransferase from BHK-21B cells. Biochem J 2001; 357:803-10. [PMID: 11463351 PMCID: PMC1222010 DOI: 10.1042/0264-6021:3570803] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Fucosyltransferase III [galactoside 3(4)-L-fucosyltransferase; EC 2.4.1.65] (FT3) is a Golgi type II membrane protein that catalyses the synthesis of fucosylated Lewis motifs that are associated with cell-adhesion events and are differentially expressed during cell differentiation. In the present work, the full-length membrane bound form of FT3 has been expressed in baby hamster kidney cells. The enzyme has been found in the trans-Golgi and trans-Golgi network (TGN) of the transfected cells, where it appeared as monomers and dimers, but not as oligomers with high molecular masses. Therefore oligomerization is not the basis for correct localization of FT3 in the Golgi. The enzyme has been purified, with a final yield of 2% and a total purification of 2900-fold, by DEAE-Sepharose, SP-Sepharose, GDP-Fractogel and Superdex 200 chromatography. The purified enzyme showed a clear preference for the Gal beta 3GlcNAc motif in oligosaccharides conjugated with the hydrophobic tail (CH(2))(3)-NHCO-(CH(2))(5)-NH-biotin. Substitution of galactose with alpha 2-linked fucose or alpha 2,3-linked N-acetylneuraminic acid yielded a 1.9-fold increase or a 43% decrease in activity respectively. The enzyme showed no activity towards asialofetuin, a glycoprotein containing the Gal beta 3GlcNAc acceptor motif. Therefore it has been concluded that the membrane-bound form of FT3 is present in the Golgi and the TGN in an equilibrium of monomers<-->dimers, which might fucosylate glycans from glycolipids, but not from glycoproteins.
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Eifel P, Axelson JA, Costa J, Crowley J, Curran WJ, Deshler A, Fulton S, Hendricks CB, Kemeny M, Kornblith AB, Louis TA, Markman M, Mayer R, Roter D. National Institutes of Health Consensus Development Conference Statement: adjuvant therapy for breast cancer, November 1-3, 2000. J Natl Cancer Inst 2001; 93:979-89. [PMID: 11438563 DOI: 10.1093/jnci/93.13.979] [Citation(s) in RCA: 601] [Impact Index Per Article: 26.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
OBJECTIVE Our goal was to provide health-care providers, patients, and the general public with an assessment of currently available data regarding the use of adjuvant therapy for breast cancer. PARTICIPANTS The participants included a non-Federal, non-advocate, 14-member panel representing the fields of oncology, radiology, surgery, pathology, statistics, public health, and health policy as well as patient representatives. In addition, 30 experts in medical oncology, radiation oncology, biostatistics, epidemiology, surgical oncology, and clinical trials presented data to the panel and to a conference audience of 1000. EVIDENCE The literature was searched with the use of MEDLINE(TM) for January 1995 through July 2000, and an extensive bibliography of 2230 references was provided to the panel. Experts prepared abstracts for their conference presentations with relevant citations from the literature. Evidence from randomized clinical trials and evidence from prospective studies were given precedence over clinical anecdotal experience. CONSENSUS PROCESS The panel, answering predefined questions, developed its conclusions based on the evidence presented in open forum and the scientific literature. The panel composed a draft statement, which was read in its entirety and circulated to the experts and the audience for comment. Thereafter, the panel resolved conflicting recommendations and released a revised statement at the end of the conference. The panel finalized the revisions within a few weeks after the conference. The draft statement was made available on the World Wide Web immediately after its release at the conference and was updated with the panel's final revisions. The statement is available at http://consensus.nih.gov. CONCLUSIONS The panel concludes that decisions regarding adjuvant hormonal therapy should be based on the presence of hormone receptor protein in tumor tissues. Adjuvant hormonal therapy should be offered only to women whose tumors express hormone receptor protein. Because adjuvant polychemotherapy improves survival, it should be recommended to the majority of women with localized breast cancer regardless of lymph node, menopausal, or hormone receptor status. The inclusion of anthracyclines in adjuvant chemotherapy regimens produces a small but statistically significant improvement in survival over non-anthracycline-containing regimens. Available data are currently inconclusive regarding the use of taxanes in adjuvant treatment of lymph node-positive breast cancer. The use of adjuvant dose-intensive chemotherapy regimens in high-risk breast cancer and of taxanes in lymph node-negative breast cancer should be restricted to randomized trials. Ongoing studies evaluating these treatment strategies should be supported to determine if such strategies have a role in adjuvant treatment. Studies to date have included few patients older than 70 years. There is a critical need for trials to evaluate the role of adjuvant chemotherapy in these women. There is evidence that women with a high risk of locoregional tumor recurrence after mastectomy benefit from postoperative radiotherapy. This high-risk group includes women with four or more positive lymph nodes or an advanced primary cancer. Currently, the role of postmastectomy radiotherapy for patients with one to three positive lymph nodes remains uncertain and should be tested in a randomized controlled trial. Individual patients differ in the importance they place on the risks and benefits of adjuvant treatments. Quality of life needs to be evaluated in selected randomized clinical trials to examine the impact of the major acute and long-term side effects of adjuvant treatments, particularly premature menopause, weight gain, mild memory loss, and fatigue. Methods to support shared decision-making between patients and their physicians have been successful in trials; they need to be tailored for diverse populations and should be tested for broader dissemination.
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Costa J, de Oliveira EI, Rosa MM, Ferreira JJ, Sampaio C, Carneiro AV. [Cardiac effects of acute poisoning with tricyclic antidepressants: systematic review of the literature -- Part II]. Rev Port Cardiol 2001; 20:765-72. [PMID: 11582626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
Tricyclic antidepressant overdose is a frequent diagnosis in the emergency room. It is responsible for a significant percentage of hospital admissions for observation and treatment. This is due to its cardiac (as well as neurologic) toxicity, and the difficulty in predicting its clinical gravity. The authors present this paper with two objectives in mind: 1) information about a common and significant cardiological emergency; 2) presentation of the methodology concerning systematic reviews of the literature. In this second (of four) articles, the clinical presentation and diagnosis of tricyclic antidepressant overdose are presented (in the first article--published in the previous issue of the Journal--we discussed the epidemiological aspects). In the remaining two papers we will present its management, prognosis and prevention. NOTE: This is the second of a series of four articles on the cardiac toxicity of tricyclic antidepressant overdose; the next two articles will be presented in the September and October issues of the Revista.
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David S, Ordway D, Arroz MJ, Costa J, Delgado R. Activity against Mycobacterium tuberculosis with concomitant induction of cellular immune responses by a tetraaza-macrocycle with acetate pendant arms. Res Microbiol 2001; 152:569-76. [PMID: 11501675 DOI: 10.1016/s0923-2508(01)01231-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The novel tetraaza-macrocyclic compound 3,7,11-tris(carboxymethyl)-3,7,11,17-tetraaza-bicyclo[11.3.1]heptadeca-1(17),13,15-triene, abbreviated as ac3py14, was investigated for its activity against Mycobacterium tuberculosis and for induction of protective cellular immune responses. Perspective results show that ac3py14 and its Fe3+ 1:1 complex, [Fe(ac3py14)], inhibited radiometric growth of several strains of M. tuberculosis. Inhibition with 25 microg/mL varied from 99% for H37Rv to 80% and above for multiple drug-resistant clinical isolates. The capacity of ac3py14 to elicit a beneficial immune response without cellular apoptosis was assessed and compared to the effects of virulent M. tuberculosis. The present study produces evidence that after stimulation with ac3py14 there was significant production of interferon gamma (IFN-gamma), whereas the production of interleukin-5 (IL-5) remained low, and there was development of a memory population (CD45RO). The level of binding of Annexin V, a marker of apoptosis, was not sufficient to result in toxic effects toward alphabeta and gammadelta T cells and CD14+ macrophages. This preliminary study is the first report of a compound that simultaneously exerts an inhibitory effect against M. tuberculosis and induces factors associated with protective immune responses.
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280
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Palma AS, Vila-Verde C, Pires AS, Fevereiro PS, Costa J. A novel plant alpha4-fucosyltransferase (Vaccinium myrtillus L.) synthesises the Lewis(a) adhesion determinant. FEBS Lett 2001; 499:235-8. [PMID: 11423123 DOI: 10.1016/s0014-5793(01)02568-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We have partially characterised an alpha4-fucosyltransferase (alpha4-FucT) from Vaccinium myrtillus, which catalysed the biosynthesis of the Lewis(a) adhesion determinant. The enzyme was stable up to 50 degrees C. The optimum pH was 7.0, both in the presence and in the absence of Mn(2+). The enzyme was inhibited by Mn(2+) and Co(2+), and showed resistance towards inhibition with N-ethylmaleimide. It transferred fucose to N-acetylglucosamine in the type I Galbeta3GlcNAc motif from oligosaccharides linked to a hydrophobic tail and glycoproteins (containing the type I motif). Sialylated oligosaccharides containing the type II Galbeta4GlcNAc motif were not acceptors. The catalytic mechanism of the plant alpha4-FucT possibly involves a His residue, and it must have arisen by convergent evolution relative to its mammalian counterparts.
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281
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Dillon D, Zheng K, Costa J. Rapid, efficient genotyping of clinical tumor samples by laser-capture microdissection/PCR/SSCP. Exp Mol Pathol 2001; 70:195-200. [PMID: 11417998 DOI: 10.1006/exmp.2001.2362] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND Mutation analysis is becoming increasingly important in clinical practice, since sporadic mutations in tumors often correlate with prognosis and/or therapeutic response. However, the labor-intensive nature of the molecular analyses has limited the routine clinical use of tumor genotyping. Laser-capture microdissection (LCM) allows procurement of relatively pure tumor cell populations. We have investigated the possibility that the use of laser-capture microdissection would allow elimination of time-consuming intermediate steps in tumor genotyping. Design. Archival formalin-fixed, paraffin-embedded tissues from seven cases of colorectal adenocarcinoma were laser- and hand-microdissected and subsequently evaluated by PCR/SSCP/sequencing for Ki-ras exon 1 and p53 exons 5, 7, and 8. Results. Mutations in Ki-ras exon 1 and/or p53 exons 5 and 7 were detected in five of the seven samples. In the hand-microdissected samples, confident identification of mutations was possible in several cases only after band excision, DNA elution, reamplification, and verification of mutant enrichment by a second SSCP analysis prior to sequencing. In the laser-microdissected samples, confident mutation identification was possible in all cases with direct sequencing of the original PCR product, reducing the time required for molecular analysis to 3 days. Conclusion. Using laser-capture microdissection, mutant signals are strong enough to sequence directly from original PCR products. With rapid, efficient genotyping by LCM/PCR/SSCP, results can be incorporated directly into the surgical pathology report.
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282
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Costa J, Rosa MM, Ferreira JJ, Sampaio C, Vaz Carneiro A. [Cardiac effects of acute poisoning with tricyclic antidepressants: systematic review of the literature. Part I]. Rev Port Cardiol 2001; 20:671-8. [PMID: 11525075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
Tricyclic antidepressant overdose is a frequent diagnosis in the emergency room. It is responsible for a significant percentage of hospital admissions for observation and treatment. This is due to its cardiac (as well as neurologic) toxicity, and the difficulty in predicting its clinical gravity. The authors present the paper with two objectives in mind: 1) information about a common and significant cardiological emergency; 2) presentation of the methodology concerning systematic reviews of the literature. In this first (of four) articles, the epidemiology tricyclic antidepressant overdose is presented. In the remaining three papers we will present its clinical presentation, diagnosis, treatment, prognosis and prevention. Note: this is the first of a series of four articles on the cardiac toxicity of tricyclic antidepressant overdose; the next three articles will be presented in the July, August and September issues of the RPC.
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283
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Doolittle BR, Emanuel J, Tuttle C, Costa J. Detection of the mutated K-Ras biomarker in colorectal carcinoma. Exp Mol Pathol 2001; 70:289-301. [PMID: 11418008 DOI: 10.1006/exmp.2001.2364] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study describes an advantageous, effective protocol for detecting K-Ras mutations in human stool as a prototype screen for colorectal carcinoma (CRC), the third most common malignancy in the United States. A reliable screening test that detects early lesions would contribute to a decrease in mortality. Currently, the only noninvasive screen for CRC is the hemeoccult, test which has a high false-positive rate. Previously, several investigators have identified genetic biomarkers for CRC in stool DNA. The K-Ras oncogene, mutated in 46-50% of CRC tumors, serves as one molecular marker by which stool samples may be evaluated for early detection of adenocarcinomas. DNA was isolated from stool samples by a new method we specifically designed for extracting high-quality DNA using tetradecyltrimethylammonium oxalate [Catrimox-14, Iowa Biotechnology Corp., (currently Qiagen)]. This protocol produces an optimal yield of high-purity DNA, suitable for genotyping. Detection of the human gene in stool samples was enhanced by hybrid selection of the K-Ras sequences, polymerase chain reaction, and single-strand conformation polymorphism. Tumor tissue and preoperative stool samples for eight patients were K-Ras genotyped and compared; stool samples from two asymptomatic, healthy patients were also evaluated in a double-blind format. In seven of eight samples (87%), the genotypes of the stool and colon tissue DNA were the same. Both healthy patients showed wild-type K-Ras. This protocol shows promise for the development of an efficient and accurate screen for CRC.
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284
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Boiko Y, Costa J, Wang MM, Esener S. Cationic two-photon induced polymerization with high dynamic range. OPTICS EXPRESS 2001; 8:571-584. [PMID: 19417855 DOI: 10.1364/oe.8.000571] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Cationic-induced two-photon photo-polymerization is demonstrated at 710 nm, using an isopropylthioxanthone / diarylidonium salt initiating system for the cationic polymerization of an epoxide. In-situ monitoring of the polymer conversion using interferometry allows for determination of the polymerization threshold J2th, polymerization rate R and its dependence of initiator's concentration z. Best J2th achieved is 1 GW/cm 2 , with a dynamic range of > 100, i.e. the material can be fully polymerized at intensities > 100 times the threshold level without damage. The R is found to be proportional to the m=1.7 power of the intensity, or R =[C(J-J2th)]m =[C(J-J2th)]1.7 , which implies a significantly stronger localization of the photochemical response than that of free radical photoinitiators. Both R and J2th significantly improve when the concentration z of the initiator (onium salt) increases, reduction of J2th exhibiting z -m trend.
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285
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Peacock CS, Collins A, Shaw MA, Silveira F, Costa J, Coste CH, Nascimento MD, Siddiqui R, Shaw JJ, Blackwell JM. Genetic epidemiology of visceral leishmaniasis in northeastern Brazil. Genet Epidemiol 2001; 20:383-96. [PMID: 11255246 DOI: 10.1002/gepi.8] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Familial clustering of disease, racial differences in asymptomatic:disease ratios, and studies of mice all point to a genetic component for disease susceptibility in visceral leishmaniasis. Analysis of 87 multi-case pedigrees (824 individuals; 138 nuclear families) from a region of northeastern Brazil endemic for Leishmania chagasi demonstrates a high relative risk ratio (lambda(2S) = 34) to further siblings of affected sibling pairs. Complex segregation analysis using POINTER and COMDS show that all single locus models, as well as polygenic and multifactorial models, provide a significantly (P < 0.001) better fit to the data than a sporadic model. Of the genetic models, the general single locus model was not significantly different from additive or dominant single locus models, all of which gave a gene frequency for the putative disease susceptibility allele of approximately 0.002. The general single locus model was strongly favored (P < 0.001) over a recessive single gene model. Using POINTER, polygenic and multifactorial models were clearly rejected (P < 0.001 in all cases) in favor of the general single locus model. Using COMDS, the analysis was extended to consider two locus models. Results under a general two-locus model did not differ significantly from the dominant, additive, or general single locus models. Under this model, one locus was estimated at a gene frequency of 0.0017, i.e., in the same range as the disease susceptibility locus for the most favored single gene models, with the second locus at a much lower frequency of 0.0002. Hence, the data support the hypothesis that a single major gene may be important in determining disease susceptibility in this population. To identify the gene(s) involved, a genome scan with replication using two subsets of these larger pedigrees with power to detect linkage is in progress.
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286
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Panzera F, Pérez R, Nicolini P, Hornos S, Costa J, Borges E, Diotaiuti L, Schofield CJ. Chromosome homogeneity in populations of Triatoma brasiliensis Neiva 1911 (Hemiptera - reduviidae - triatominae). CAD SAUDE PUBLICA 2001; 16 Suppl 2:83-8. [PMID: 11119323 DOI: 10.1590/s0102-311x2000000800009] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Triatoma brasiliensis is the most important vector of Chagas disease in the semiarid zone of the Northeast of Brazil. Several authors have reported the occurrence of four chromatic patterns with morphological, ecological, and genetic differences. In order to determine the existence of cytogenetic differentiation between these chromatic forms, we analyzed their karyotypes and the chromosome behavior during the male meiotic process. Triatoma brasiliensis shows distinct and specific chromosome characteristics, which differ from those observed in all other triatomine species. However, no cytogenetic differences were observed between the four chromatic forms of T. brasiliensis. The lack of chromosome differentiation among them could indicate that the populations of this species are in a process of differentiation that does not involve their chromosomal organization.
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Costa J. [Distribution and characterization of different populations of Triatoma brasiliensis Neiva, 1911 (Hemiptera, Reduviidae, Tritominae)]. CAD SAUDE PUBLICA 2001; 16 Suppl 2:93-5. [PMID: 11119325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
Triatoma brasiliensis Neiva, 1911 is now considered the most important Chagas disease vector in the semiarid zones of northeastern Brazil. Four distinct populations of T. brasiliensis have been identified by multidisciplinary studies: brasiliensis (Caicó, RN), melânica (Espinosa, MG), macromelasoma (Petrolina, PE), and juazeiro (Juazeiro, BA). By scanning electron microscopy of egg exochorion, each population displayed a distinct ornamentation pattern. The brasiliensis, macromelasoma, and juazeiro populations were found in both artificial ecotopes and the wild, while the mel anica population was collected only in the wild. Isoenzymatic analysis detected phenotypic and genetic differences among them, with the melânica population being the most distinct. The brasiliensis population is the most important one from an epidemiological point of view, with the widest geographic distribution, the highest Trypanosoma cruzi infection rate, and occupying a wide variety of ecotopes.
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Salgado A, Costa J, Rebelo A, Brandão A, Primo J, Vieira A, Araújo O. [Complete congenital atrioventricular block]. Rev Port Cardiol 2001; 20:305-10. [PMID: 11417313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023] Open
Abstract
Congenital atrioventricular block is defined (Yater) as a documented conduction defect in a young subject with unquestionable bradycardia in the absence of a history of infection which might have caused the condition. This condition may be isolated or associated with structural cardiac disease. Isolated block is often observed in patients with mothers suffering from autoimmune disease, often clinically latent. Anti-Ro/SS-A and La/SS-B antibodies cross into the fetal circulation and cause inflammation of the fetal conduction system. The diagnosis of the conduction defect is sometimes made during fetal life by echocardiography. Echocardiography assesses fetal hemodynamic status and may detect signs of fetal deterioration. Long-term follow-up studies have revised the previously considered good prognosis of isolated congenital atrioventricular block but advances in cardiac pacing provide satisfactory treatment. Follow-up by Holter monitoring, exercise testing and echocardiography is justified in children and adolescents; the patients may become symptomatic at any age. Indications for permanent pacing in pediatric patients have been difficult to determine due to the lack of data from controlled studies and multicenter trials. Pacing is not always easy in children. Epicardial pacing is advocated in small patients (< 5 years of age or 30 kg in weight). A pacing mode which restores the normal atrioventricular sequence is theoretically superior to single ventricular pacing even with rate responsive frequency.
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Morais VA, Serpa J, Palma AS, Costa T, Maranga L, Costa J. Expression and characterization of recombinant human alpha-3/4-fucosyltransferase III from Spodoptera frugiperda (Sf9) and Trichoplusia ni (Tn) cells using the baculovirus expression system. Biochem J 2001; 353:719-25. [PMID: 11171070 PMCID: PMC1221619 DOI: 10.1042/0264-6021:3530719] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The human alpha-3/4-fucosyltransferase III (Fuc-TIII) participates in the synthesis of Lewis determinants. The enzyme from human sources is scarce and heterogeneous. In this paper we describe the expression of a secreted form of Fuc-TIII (SFT3) in two insect cell lines, Spodoptera frugiperda (Sf9) and Trichoplusia ni (Tn), using the baculovirus expression system. The Sf9 cells secreted approx. 0.4 unit/l (1 mg/l) of the enzyme. The Tn cells secreted approx. 3-fold this amount. A large proportion of active protein was accumulated in the two cell lines (50 and 75% respectively for Sf9 and Tn cells, on the fourth day after infection) indicating a possible limitation not only of the folding machinery, but also a saturation of the secretory pathway. SFT3 was purified by cation-exchange chromatography followed by affinity chromatography. The enzyme from the Tn cell line had a lower global charge, possibly due to post-translational modifications, such as phosphorylation or sulphation. The two glycosylation sites from SFT3 were occupied. SFT3 secreted by Sf9 cells was completely deglycosylated by peptide-N-glycanase F, whereas 50% of SFT3 secreted by Tn cells was resistant to deglycosylation by this enzyme. The apparent kinetic parameters determined with the type I acceptor were k(cat)=0.4 s(-1) and K(m)=0.87 mM for the SFT3 secreted by Tn cells, and k(cat)=0.09 s(-1) and K(m)=0.76 mM for the SFT3 secreted by Sf9 cells, indicating that the enzymes had substrate affinities within the same order of magnitude as their mammalian counterpart. Furthermore, SFT3 secreted by either cell type showed a clear preference for type 1 carbohydrate acceptors, similarly to human Fuc-TIII.
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290
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Segovia R, Sánchez-Fueyo A, Rimola A, Grande L, Bruguera M, Costa J, Soguero C, Uriz J. Evidence of serious graft damage induced by de novo hepatitis B virus infection after liver transplantation. Liver Transpl 2001; 7:106-12. [PMID: 11172393 DOI: 10.1053/jlts.2001.21457] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
De novo hepatitis B virus (HBV) infection after orthotopic liver transplantation (OLT) is commonly believed to be a relatively benign condition, in contrast to post-OLT infection recurrence, considered a very aggressive complication. We reviewed the charts of 569 non-HBV-related OLTs performed at our institution and identified 19 patients (3%) with de novo HBV infection (appearance of hepatitis B surface antigen [HBsAg] after OLT). After a median follow-up of 25 months beyond the detection of HBsAg, 12 patients (63%) had developed serious HBV-related graft damage (cirrhosis in 6 patients, bridging chronic hepatitis in 4 patients, and fulminant hepatitis in 2 patients); 7 patients (37%) had lost their grafts; and 4 patients (21%) had died. All graft losses and deaths were related to de novo HBV infection. Similar rates of severe graft damage (62%), graft loss (38%), and death (33%) related to HBV infection were found in a concomitant series of 21 patients with recurrent HBV infection after OLT. Responses to antiviral therapy (interferon or lamivudine) were also similar in the 2 groups of patients. In 12 patients with de novo HBV infection, evidence of past HBV infection (positive serum antibody to hepatitis B core antigen and/or serum or liver tissue HBV DNA) were detected in the donor (7 patients) or recipient (5 patients). No differences were observed in the clinical course after stratification according to the attributed origin of de novo HBV infection. We conclude that de novo HBV infection after OLT is associated with high rates of morbidity and mortality, similar to those described for post-OLT HBV infection recurrence.
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291
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Ferrington DA, Sun H, Murray KK, Costa J, Williams TD, Bigelow DJ, Squier TC. Selective degradation of oxidized calmodulin by the 20 S proteasome. J Biol Chem 2001; 276:937-43. [PMID: 11010965 DOI: 10.1074/jbc.m005356200] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We have investigated the mechanisms that target oxidized calmodulin for degradation by the proteasome. After methionine oxidation within calmodulin, rates of degradation by the 20 S proteasome are substantially enhanced. Mass spectrometry was used to identify the time course of the proteolytic fragments released from the proteasome. Oxidized calmodulin is initially degraded into large proteolytic fragments that are released from the proteasome and subsequently degraded into small peptides that vary in size from 6 to 12 amino acids. To investigate the molecular determinants that result in the selective degradation of oxidized calmodulin, we used circular dichroism and fluorescence spectroscopy to assess oxidant-induced structural changes. There is a linear correlation between decreases in secondary structure and the rate of degradation. Calcium binding or the repair of oxidized calmodulin by methionine sulfoxide reductase induces comparable changes in alpha-helical content and rates of degradation. In contrast, alterations in the surface hydrophobicity of oxidized calmodulin do not alter the rate of degradation by the proteasome, indicating that changes in surface hydrophobicity do not necessarily lead to enhanced proteolytic susceptibility. These results suggest that decreases in secondary structure expose proteolytically sensitive sites in oxidized calmodulin that are cleaved by the proteasome in a nonprocessive manner.
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292
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Rimm DL, Camp RL, Charette LA, Costa J, Olsen DA, Reiss M. Tissue microarray: a new technology for amplification of tissue resources. Cancer J 2001; 7:24-31. [PMID: 11269645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Tissue microarrays are a method of harvesting small disks of tissue from a range of standard histologic sections and placing them in an array on a recipient paraffin block such that hundreds of cases can be analyzed simultaneously. This technique allows maximization of tissue resources by analysis of small-core biop sies of blocks, rather than complete sections. Using this technology, a carefully planned array can be constructed with cases from pathology tissue block archives, such that a 20-year survival analysis can be performed on a cohort of 600 or more patients by use of only a few microliters of antibody in a single experiment. The reflex criticism of this technique is that the tissue analyzed is not representative, especially in antigens with heterogeneous staining patterns. This review addresses this issue, as well as the issue of antigen preservation or durability, which validates construction of arrays from archives. Strategies and methods of construction and analysis of the arrays are discussed, as well as some other unusual array applications. This technique can provide a highly efficient, high-throughput mechanism for evaluation of protein expression in large cohorts. It has the potential to allow validation of new genes at a speed comparable to the rapid rate of gene discovery afforded by DNA microarrays.
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293
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Sampaio C, Ferreira J, Costa J. [Numbers needed for treatment and their respective confidence intervals: useful tools to assess clinical significance and uncertainty associated with medical interventions]. Rev Port Cardiol 2000; 19:1303-8. [PMID: 11220124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
This is a narrative review of a concept--number needed to treat (NNT). The proprieties of NNTs are described. Furthermore NNTs as important tools for medical decision are discussed. In particular, conditions that make calculus and the interpretation of NNTs somewhat more complex are commented. Namely, we consider situations where the results are not primarily binary or are expressed as "time to event" or come from a meta-analysis. The inconsistencies that might occur when NNTs are calculated from meta-analysis are discussed in some detail. Definitions for parameters derived from NNTs, as numbers needed to harm (NNH), unqualified success (NNTUS) and unmitigated failure (NNHUF) are given. Finally the usefulness of NNTs and absolute risk reductions to communicate risk to individual patients are considered. It is concluded that despite NNTs being powerful tools for medical decision, in the case of communicating risks to the individual patient absolute risks might be preferable.
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Almeida CE, Vinhaes MC, de Almeida JR, Silveira AC, Costa J. Monitoring the domiciliary and peridomiciliary invasion process of Triatoma rubrovaria in the State of Rio Grande do Sul, Brazil. Mem Inst Oswaldo Cruz 2000; 95:761-8. [PMID: 11080758 DOI: 10.1590/s0074-02762000000600003] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The presence of Triatoma rubrovaria in Brazil has only been confirmed in the States of Paraná and Rio Grande do Sul (RS), where it is found naturally infected with Trypanosoma cruzi. In the wild environment it occurs in rocky habitats and has an eclectic diet, feeding from cockroaches, reptiles and mammals. Data from the Chagas Disease Control Program obtained by the Fundação Nacional de Saúde, between 1975 and 1997, indicate a growing domiciliary and peridomiciliary invasion of T. rubrovaria in RS, where it has become the most frequently Triatominae species captured in this state since the control of Triatoma infestans. In order to monitor this process, we analyzed collection data derived from 22 years of control campaigns against T. infestans. Collection data for triatomines from domestic habitats show an inverse relationship, with high numbers of T. infestans and low numbers of T. rubrovaria during 1976-1987, compared to the following ten years, 1986-1997, when the number of T. infestans dropped drastically and that of T. rubrovaria increased. There are no consistent indications of intradomiciliary colonization by T. rubrovaria, since only low numbers of nymphs have been captured in the intradomiciliary ecotopes. Nevertheless, this species appears to have preadaptive characteristics for anthropic ecotopes, and should be kept under constant epidemiological surveillance.
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295
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Torres M, Campins M, Esteban JI, Costa J, Bastida MT, Bruguera M. Is it useful to perform the RNA test for hepatitis C in health care workers after an accidental needlestick? J Hepatol 2000; 33:686. [PMID: 11059880 DOI: 10.1034/j.1600-0641.2000.033004686.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
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296
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Abstract
OBJECTIVES To investigate the breast-feeding (BF) situation after birth of twins and find what factors affect the decision to breast-feed, its length and the reasons for stopping it. DESIGN Retrospective, observational study. SETTING Sabadell Hospital, Barcelona. PARTICIPANTS All the women who gave birth to twins between January 1994 and June 1997 (n = 72). MAIN RESULTS 64 women (88.9%) began BF. It was exclusive in 37 cases (57.8%) and mixed in the other 27 (42.2%). The main reason for choice was "better feeding" (100% of cases). The age of mothers, the type of birth, the weight of the children, admissions to the New-born Baby Department, work situation, mother's educational qualifications and the existence of domestic help affected neither initial breast-feeding nor its length. Women with prior counselling started BF in greater numbers than those not counselled (p = 0.026). Almost half of them received the information through the matron or nurse. Mean length of BF was 102 days. After two months, half of those who began BF were still breast-feeding; and at four months, 26.5%. CONCLUSIONS We observed a high level of starting breast-feeding after twin births, almost the same as for single births. Women with previous knowledge of the question are more likely to breast-feed. The length of BF is slightly greater in the studies reviewed. Adequate prenatal, postnatal and puerperal support from health-workers can have a positive effect on the success of BF after twin births.
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297
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Costa J. The synanthropic process of Chagas disease vectors in Brazil, with special attention to Triatoma brasiliensis Neiva, 1911 (Hemiptera, reduviidae, triatominae) population, genetical, ecological, and epidemiological aspects. Mem Inst Oswaldo Cruz 2000; 94 Suppl 1:239-41. [PMID: 10677724 DOI: 10.1590/s0074-02761999000700038] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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298
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Salgado A, Brandão A, Costa J, Araújo O. Renovascular hypertension due to angiodysplasia. Rev Port Cardiol 2000; 19:935-7. [PMID: 11109876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
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299
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Almeida CE, Ramos EF, Gouvêa E, do Carmo-Silva M, Costa J. Natural history of Ctenus medius Keyserling, 1891 (Araneae, Ctenidae) I: observations on habitats and the development of chromatic patterns. REVISTA BRASILEIRA DE BIOLOGIA 2000; 60:503-9. [PMID: 11188876 DOI: 10.1590/s0034-71082000000300015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ctenus medius Keyserling, 1891 is a common species in several spots of Mata Atlântica, however there is a great lack of studies in all aspects of its natural history. This work aims to elucidate aspects of ecotope preference compared to large spiders, and to provide data on the development of chromatic patterns during its life cycle. The observations on the behavior of C. medius were done in the campus of Centro Universitário de Barra Mansa (UBM) by means of observations and nocturnal collections using cap lamps. For observations on the development of chromatic patterns, spiderlings raised in laboratory, hatched from an oviposition of a female from campus of UBM, and others spiderlings collected in field were used. The field observations indicate that: C. medius seems to prefer ecotopes characterized by dense shrub vegetation or herbal undergrowth; Lycosa erythrognatha and L. nordeskioldii seems to prefer open sites; Phoneutria nigriventer seems to prefer shrub vegetation and anthropogenic ecotopes as rubbish hills; Ancylometes sp. seems to prefer ecotopes near streams. Concerning chromatic patterns, it was observed that males and females show well distinct patterns during the last two instars, allowing distinction by sex without the use of a microscope. Through chromatic patterns it was also possible to draw a distinction between C. medius and C. ornatus longer that 3 mm cephalothorax width. 69 specimens of C. medius (males and females) collected in the campus of UBM did not show a striking polymorphism in chromatic pattern, but one among 7 adult females collected in National Park of Itatiaia, showed a distinct chromatic pattern.
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Abstract
CONTEXT Text reports convey critical medical information from pathologists, radiologists, and subspecialty consultants. These reports must be clear and comprehensible to avoid medical errors. Pathologists have paid much attention to report completeness but have ignored the corresponding issue of report comprehension. This situation presents an increasingly serious potential problem. As laboratories are consolidated and as reports are disseminated in new ways (eg, via the World Wide Web), the target audience becomes more diverse and less likely to have any contact with pathologists beyond the written reports themselves. OBJECTIVE To compare clinician comprehension with pathologist intent in written pathology reports. METHODS Typical surgical pathology reports relevant to surgeons and covering a range of specimen complexity were taken from our hospital files. Questionnaires based on these cases were administered open-book-examination style to surgical attending physicians and trainees during surgical conferences at an academic medical center. MAIN OUTCOME MEASURES Scores from questionnaires. RESULTS Surgeons misunderstood pathologists' reports 30% of the time. Surgical experience reduced but did not eliminate the problem. Streamlined report formatting exacerbated the problem. CONCLUSIONS A communication gap exists between pathologists and surgeons. Familiarity with report format and clinical experience help reduce this gap. Paradoxically, stylistic improvements to report formatting can interfere with comprehension and increase the number of misunderstandings. Further investigation is required to reduce the number of misunderstandings and, thus, medical errors.
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