Biomedical subjects

E Garcia

Publications and source records attributed to E Garcia.

At least 109 records · Page 6Linked to original sources

PubMed1997

MUC6 gene polymorphism in healthy individuals and in gastric cancer patients from northern Portugal.

Mucins exhibit a high degree of genetic polymorphism because of the presence of a variable number of tandem repeats. The aims of this work were to describe the MUC6 gene polymorphism in the Portuguese population and to evaluate whether MUC6 gene polymorphism was involved in individual susceptibility to gastric cancer development, as observed previously for the MUC1 gene. We found that the 10 alleles identified in the population of blood donors (n = 376), by Southern blot analysis, were also found in gastric cancer patients (n = 157). However, significant differences in allelic frequencies between the two populations were observed for 4 of the 10 alleles, in agreement with those described previously for the MUC1 gene; the largest allele was more frequent in blood donors, and smaller alleles were more frequent in gastric cancer patients. Our results suggest that MUC6 gene polymorphism is involved in the predisposition to gastric carcinoma development.

Adult↗

PubMed1997

Cloning, characterization and identification of the gene encoding phosphatidylinositol 4-kinase.

The vast majority of AIDS-related deaths are associated with opportunistic infections. For fungal infections, there are few effective antifungals, particularly for systemic use. The discovery that very low doses of the bleomycin family of anticancer chemical congeners compromise the integrity of fungal cell walls led to our approach to identify genes that complement-cell wall defects, and develop methods to facilitate the identification of new antifungals targeted to fungal cell walls. This report describes one of the genes cloned by complementation of the blm1-1 mutation of S. cerevisiae using a YCp50-based yeast genomic library. Characterization and identification of the gene were carried out using drug screening tests, Southern hybridization analyses, DNA sequencing and DNA sequence similarity searches in databases. The gene STT4, is essential for viability and encodes a phosphatidylinositol 4-kinase that plays an important role in the phosphatidylinositol-mediated signal transduction pathway required for cell wall integrity. Like blm1-1 mutant strains, stt4 cells arrest mostly in the G2/M phase of the cell cycle. Further studies using this approach should help us understand the role of PI4-K in maintaining fungal cell-wall integrity, identify additional genes affecting potential target structures in cell walls of opportunistic fungal pathogens in AIDS patients, and assist in drug discovery and antifungal drug design.

1-Phosphatidylinositol 4-Kinase↗

PubMed1996

Structure, sequence, and chromosome 19 localization of human USF2 and its rearrangement in a patient with multicystic renal dysplasia.

The precise etiology of hydronephrosis caused by pelvi-ureteric junction obstruction is not yet known but there is convincing evidence for a genetic cause, with linkage analysis predicting a hereditary hydronephrosis locus on chromosome 6p. In previous studies, a patient was described with a de novo autosomal t(6;19)(p21;q13.1) translocation and suffering from bilateral multicystic renal dysplasia (MRD) caused by a bilateral complete pelvi-ureteric junction obstruction. In an effort to elucidate a possible correlation between this translocation and hereditary hydronephrosis, we have carried out an extensive molecular characterization of a chromosome 19 cosmid clone previously identified as spanning the translocation in this unique index case. DNA sequencing across a 9.2-kb BamHI fragment that straddles the translocation indicates the presence of DNA sequences with a high degree of similarity to the USF2 gene that encodes the transcription factor USF2 (upstream stimulator factor 2). The genomic structure of USF2 consists of 10 exons distributed over a DNA region of about 11 kb. The putative promoter region is GC-rich and lacks TATA and CCAAT boxes, suggesting that expression of the USF2 gene may be controlled by a typical housekeeping gene promoter. The chromosome 19 breakpoint in the MRD patient appeared to have occurred in intron 7 of the USF2 gene. Northern blot analysis of a variety of human tissues revealed that the USF2 gene is ubiquitously expressed. Furthermore, Northern blot and 3'-RACE analysis of mRNA isolated from lung fibroblasts of the MRD patient failed to detect a fusion transcript involving USF2 sequences, suggesting gene disruption rather than the generation of a fusion gene as a possible underlying mechanism.

Amino Acid Sequence↗

PubMed1996

Interleukin (IL)-10 and IL-6 are produced in vivo by non-Hodgkin's lymphoma cells and act as cooperative growth factors.

The in vivo production of interleukin (IL)-10, IL-6, IL-2, and tumor necrosis factor (TNF)-alpha in tumor samples was investigated by immunohistochemistry in 54 non-Hodgkin's lymphomas (NHLs). Respectively, 55, 89, 23, and 29% of tumor samples were found positive for IL-10, IL-6, IL-2, and TNF-alpha expression by immunohistochemistry. Using reverse transcription-PCR, the mRNA of IL-10 and IL-6 were detectable in all samples tested and in 90 and 34% of the samples for TNF-alpha and IL-2, respectively. In 13 patients, fresh tumor tissue was available for B NHL cell purification with Dynabeads. IL-10, IL-6, IL-2, and TNF-alpha were detectable in the supernatant of 38, 100, 0, and 23% of purified tumor cell preparations (PTCPs), respectively. All patients with detectable IL-10 in culture had increased serum IL-10. IL-6 production by tumor cells and serum IL-6 levels were also found to be highly correlated (P < 0.0001). This suggests that tumor cells are a major source of serum IL-1O and IL-6 in these patients. Exogenous IL-10, IL-6, IL-2, and TNF-alpha significantly enhanced the [3H]thymidine uptake in 13 of 13 (100%), 5 of 13 (38%), 9 of 13 (69%), and 2 of 10 (20%) PTCPs costimulated with anti-CD40, respectively. IL-2, IL-6, and TNF-alpha synergized with IL-10 in 54, 23, and 30% of PTCPs. The combination of IL-10, IL-2, and IL-6 induced the maximal level of proliferation in 12 (92%) of 13 PTCPs. CD40 ligand mRNA expression was also detectable in vivo using reverse transcription-PCR in 28 of the 29 (97%) tumor samples tested, including 11 of those tested for [3H]thymidine incorporation. These results show that IL-1O, IL-6, IL-2, and TNF-alpha are produced in NHL tumors and may cooperate in vivo to increase NHL cell proliferation.

B-Lymphocytes↗

PubMed1996

T cell interleukin-17 induces stromal cells to produce proinflammatory and hematopoietic cytokines.

Analysis of the cDNA encoding murine interleukin (IL) 17 (cytotoxic T lymphocyte associated antigen 8) predicted a secreted protein sharing 57% amino acid identity with the protein predicted from ORF13, an open reading frame of Herpesvirus saimiri. Here we report on the cloning of human IL-17 (hIL-17), the human counterpart of murine IL-17. hIL-17 is a glycoprotein of 155 amino acids secreted as an homodimer by activated memory CD4+ T cells. Although devoid of direct effects on cells of hematopoietic origin, hIL-17 and the product of its viral counterpart, ORF13, stimulate epithelial, endothelial, and fibroblastic cells to secrete cytokines such as IL-6, IL-8, and granulocyte-colony-stimulating factor, as well as prostaglandin E2. Furthermore, when cultured in the presence of hIL-17, fibroblasts could sustain the proliferation of CD34+ hematopoietic progenitors and their preferential maturation into neutrophils. These observations suggest that hIL-17 may constitute (a) an early initiator of the T cell-dependent inflammmatory reaction; and (b) an element of the cytokine network that bridges the immune system to hematopoiesis.

Amino Acid Sequence↗

PubMed1996

Negative selection of human germinal center B cells by prolonged BCR cross-linking.

The antigen receptors on T and B lymphocytes can transduce both agonist and antagonist signals leading either to activation/survival or anergy/death. The outcome of B lymphocyte antigen receptor (BCR) triggering depends upon multiple parameters which include (a) antigen concentration and valency, (b) duration of BCR occupancy, (c) receptor affinity, and (d) B cell differentiation stages. Herein, using anti-immunoglobulin kappa and lambda light chain antibodies, we analyzed the response of human naive, germinal center (GC) or memory B cells to BCR cross-linking regardless of heavy chain Ig isotype or intrinsic BCR specificity. We show that after CD40-activation, anti-BCR (kappa + gamma) can elicit an intracellular calcium flux on both GC and non-GC cells. However, prolonged BCR cross-linking induces death of CD40-activated GC B cells but enhances proliferation of naive or memory cells. Anti-kappa antibody only kills kappa + GC B cells without affecting surrounding gamma + GC B cells, thus demonstrating that BCR-mediated killing of GC B lymphocytes is a direct effect that does not involve a paracrine mechanism. BCR-mediated killing of CD40-activated GC B cells could be partially antagonized by the addition of IL-4. Moreover, in the presence of IL-4, prestimulation through CD40 could prevent subsequent anti-Ig-mediated cell death, suggesting a specific role of this combination in selection of GC B cells. This report provides evidence that in human, susceptibility to BCR killing is regulated along peripheral B cell differentiation pathway.

Antibodies, Anti-Idiotypic↗

PubMed1996

Heparin-coated Palmaz-Schatz stents in human coronary arteries. Early outcome of the Benestent-II Pilot Study.

BACKGROUND: The purpose of the Benestent-II Pilot Study was to evaluate the safety of delaying and eliminating anticoagulant therapy in patients receiving a heparin-coated stent in conjunction with antiplatelet drugs. METHODS AND RESULTS: The study consisted of three initial phases (I, II, III) during which resumption of heparin therapy after sheath removal was progressively deferred by 6, 12, and 36 hours. In phase IV, coumadin and heparin were replaced by 250 mg ticlopidine and 100 mg aspirin. Of the 207 patients with stable angina pectoris and a de novo lesion in whom heparin-coated stent implantation was attempted, implantation was successful in 202 patients (98%). Stent thrombosis did not occur during all four phases, and the overall clinical success rate at discharge was 99%. Bleeding complications requiring blood transfusion or surgery fell from 7.9% in phase I to 5.9%, 4%, and 0% in the three following phases. Hospital stay was 7.4, 6.1, 7.2, and 3.1 days for the consecutive phases. The restenosis rate for the combined four phases was 13% (15% in phase I, 20% in phase II, 11% in phase III, and 6% in phase IV). The overall rate of reintervention for the four phases was 8.9%. At 6 months, 84%, 75%, 94%, and 92% of the patients of phases I to IV, respectively, were event free. For the four phases, the event-free rate was 86%, which compares favorably with the rate observed in the Benestent-I study (80%; relative risk, 0.68 [0.45 to 1.04]). CONCLUSIONS: The implantation of stents coated with polyamine and end-point-attached heparin in stable patients with one significant de novo coronary lesion is well tolerated, is associated with no (sub)acute stent thrombosis, and results in a favorable event-free survival after 6 months.

Aspirin↗

PubMed1996

Medial rotational tibial osteotomy for patellar instability secondary to lateral tibial torsion.

We report 35 medial rotational osteotomies in 25 patients with chronic disability suggesting patello-femoral subluxation secondary to lateral tibial torsion. None had responded to conservative measures or soft tissue operations. The osteotomy was transverse in 17 and oblique in 18. The follow up averaged 4.3 years (range 1 to 8 years). The alignment of the limb was assessed clinically, and by radiographs and CT scans. The results were good or excellent in 88.5%, fair in 5.7% and poor in 5.7%. Twenty-three patients were satisfied and 2 were not. The overall results have been satisfactory in athletes and those leading an active life.

Adolescent↗

PubMed1996

Immunodominant synthetic peptides of Taenia crassiceps in murine and human cysticercosis.

The screening of a cDNA library of Taenia crassiceps revealed a clone designated KETc7 that induced high levels of protection against murine cysticercosis in previous experiments. The molecular structure of the deduced 100-amino acid sequence of the corresponding proline-rich polypeptide was studied to detect potentially immunologically active epitopes. Several candidate epitopes were identified, three of which were synthesized by solid-phase peptide synthesis and used as antigens in enzyme-linked immunosorbent assay (ELISA) for detection of specific antibodies in a selected panel of sera from mice infected with Taenia crassiceps and pigs infected with Taenia solium, as well as in the serum and cerebrospinal fluid of human patients with neurocysticercosis. The three peptides detected antibodies in serum from all infected mice. Seven of nine sera from patients with neurocysticercosis reacted strongly with peptide GK-3, and four of them with peptides GK-1 and GK-2. A lower reactivity was observed in sera from experimentally infected pigs. Peptide GK-3 reacted also with 45 out of 77 cerebrospinal fluids (CSF) from patients with confirmed neurocysticercosis and with 14 out of 68 CSF from control patients with other neurological disorders. This is the first report on synthetic peptides that are prominent in the humoral response of murine, porcine and human cysticercosis. Their identification implies finer molecular tools in the exploration of this form of host-parasite relationship, as well as hints to their application in immunodiagnosis and in vaccine design.

Amino Acid Sequence↗

PubMed1996

Employee compensation.

All practice owners and managers struggle with the concept of "fair compensation." Many factors enter into determining fair compensation. More managers are placing emphasis on production or contributions to the practice in making compensation decisions. Several incentive or bonus programs are discussed. If the contributions to the business can be measured, these areas may possibly be used for incentive programs. As owners and managers we need to do a better job of explaining and showing to our employees the total cost for staffing the practice.

Animals↗

PubMed1996

Effective but near disastrous subarachnoid neurolysis for mechanical root pain in a paraplegic cancer patient.

CASE REPORT: A 43-year-old white man with advanced renal cell carcinoma and consequent paraplegia complained of the new onset of lancinating pain involving the right upper chest wall. This pain, which was superimposed on well-controlled chronic back pain and was intermittent and related to activity, failed to respond to conventional pharmacologic management. METHODS AND RESULTS: A cisternal myelogram suggested an absence of gross rostral extension of spinal metastases, and subarachnoid neurolysis was performed with hyperbaric phenol. Unexpected contralateral brachial weakness developed towards the conclusion of the procedure, but resolved spontaneously. The target pain had not recurred at follow-up 8 months later.

Adult↗

PubMed1996

Isolation of cosmids corresponding to the chromosome breakpoints of a de novo autosomal translocation, t(6;19)(p21;q13.1), in a patient with multicystic renal dysplasia.

Hydronephrosis caused by pelvi-ureteric junction obstruction (PUJO) is a frequent urological malformation assumed to result from a deficient development of the ureteric bud. The exact etiology of pelvi-ureteric junction stenosis is unknown, but there is convincing evidence for a genetic cause, with linkage analysis predicting a hereditary hydronephrosis locus on chromosome 6p. We encountered a patient with a de novo autosomal t(6;19)(p21;q13.1) and attendant bilateral multicystic renal dysplasia (MRD), bilateral PUJO resulting in massive hydronephrosis, and an associated von Mayer-Rokitansky-Kuster disorder. On the basis of the presumption that in this patient the putative hydronephrosis gene might be disrupted by the translocation, we sought to isolate DNA from the breakpoint regions as the initial step in a strategy to identify genes affected by the t(6; 19). Using sequential rounds of fluorescence in situ hybridization (FISH) with cosmids selected from a detailed integrated map of the long arm of chromosome 19, we have identified a cosmid clone that spans the breakpoint. The position of the breakpoint was further localized by Southern blot analysis. Using a vectorette PCR approach, rearranged DNA fragments were isolated and, by comparative nucleotide sequence analysis, these were shown to contain ectopic sequences. A cosmid clone containing these ectopic sequences was isolated and shown by CASH (chromosome assignment using somatic cell hybrids) and FISH (fluorescence in situ hybridization) analysis to map to the short arm of chromosome 6 and to span the breakpoint found in the MRD patient. The isolated cosmid clones are useful reagents for analysis of other MRD patients and for the search for genes at or flanking the breakpoints.

Adult↗

PubMed1996

[Prevention of Listeria monocytogenes contamination on dairy farms and in the cheese industry].

Listeria monocytogenes remains a pathogen bacteria the prevention of which, in food products, stays delicate. A complete organization, from the farmer's production to the industry and the consumer is necessary to eliminate Listeria in a type of food product. Listeria monocytogenes is susceptible of contaminate raw milk. The silage may be a major source of the occurrence of Listeria monocytogenes in raw milk. In this case, the contamination sources in a dairy farm and the good hygienic practices must be well-defined. In dairy industry, the contamination must be managed by the application of a systematic and methodically system like H.A.C.C.P. (Hazard Analysis Critical Control Points). It is useful for the study of Listeria monocytogenes contamination and involve the hazard analysis of each industry plant. In fact, the raw products, food products, manufacturing process, environmental conditions, process equipment, materials and staff organizational are specific and characteristic.

Animals↗

PubMed1996

Alteration of p53 damage response by tamoxifen treatment.

Hormone therapy is often used in association with chemotherapy in the treatment of estrogen-responsive breast cancers. By using breast adenocarcinoma cell lines, we show that antiestrogen treatment leads to a dramatic decrease of p53 protein levels. This effect leads to a loss of wild-type p53 response to genotoxic treatment. This inhibition is assessed by the lack of p53 protein accumulation and the loss of the p53-dependent induction of p21(WAF1/CIP1) expression. Given that the effects of several anticancer agents are mediated through DNA damage, these observations suggest that antiestrogen treatment could modulate cellular response to chemotherapeutic agents.

DNA Damage↗

PubMed1995

Fas ligation induces apoptosis of CD40-activated human B lymphocytes.

Since CD40/CD40 ligand (CD40Lig) interactions are essential in vivo for the generation of germinal center B cells that express Fas (Apo-1/CD95), we explored whether CD40 engagement may modulate Fas expression and function on human B lymphocytes. Resting tonsil B cells, isolated by density gradient centrifugation, express either absent or low levels of Fas. They could be induced to promptly express Fas after ligation of their CD40, however, using either a recombinant human CD40Lig or a cross-linked anti-CD40 mAb. In contrast, engagement of the B cell antigen receptor by immobilized anti-kappa and -lambda antibodies did not turn on Fas expression. Addition of anti-Fas mAb CH11 inhibited the later phases of CD40-induced B cell growth as a result of apoptotic cell death. Furthermore, Fas ligation inhibited proliferation and Ig secretion of CD40-activated B cells in response to recombinant cytokines such as interleukin (IL)-2, IL-4, and IL-10, as well as a cytokine-rich supernatant of phytohemagglutinin-activated T cells, indicating that none of those B cell tropic factors were able to prevent the Fas-induced death. Taken together, the present results show that engagement of CD40 antigen on B cells induces Fas expression and sensitizes them to Fas-mediated apoptosis. The delayed functional response to Fas ligation after CD40 activation may represent a way to limit the size of a specific B cell clone that is generated during T-B cell interactions.

Animals↗

PubMed1995

Regional chromosomal assignments for four members of the MADS domain transcription enhancer factor 2 (MEF2) gene family to human chromosomes 15q26, 19p12, 5q14, and 1q12-q23.

The MEF2 genes belong to the MADS box family of transcription factors and encode proteins that bind as homo- and heterodimers to a consensus CTA(T/A)4TAG/A sequence, which is present in the regulatory regions of numerous muscle-specific and growth-inducible genes. Sequence analysis of human MEF2 cDNA clones suggests that they arose from alternatively spliced transcripts of four different genes, termed MEF2A-D. We have mapped the MEF2 genes to human chromosomal regions by identifying unique sequences in the MEF2 cDNA clones and using these sequences as PCR primers on the DNA of human-rodent hybrid clone panels that are informative for different regions of the human genome. PCR primers were also used to identify individual YAC clones for two of the genes, MEF2A and MEF2C, and a PCR product was used to identify cosmid clones for MEF2B. Genetic and physical mapping information available from genome databases on markers contained within YAC and cosmid clones provided independent assignments for those genes. Inter-Alu PCR painting probes of YAC clones were used as probes for high-resolution chromosomal regional assignment by fluorescence in situ hybridization. The localization of MEF2A to chromosome 15q26, MEF2B to 19p12, MEF2C to 5q14, and MEF2D to 1q12-q23 verifies the existence of at least four distinct loci for members of this gene family.

Alternative Splicing↗

PubMed1995

A continuous high-resolution physical map spanning 17 megabases of the q12, q13.1, and q13.2 cytogenetic bands of human chromosome 19.

We report the construction of a high-resolution physical map of a 17-Mb region that encompasses the entire q12, q13.1, and q13.2 bands of human chromosome 19. The continuous map extends from a region approximately 400 kb centromeric of the D19S7 marker to the excision repair cross-complementing rodent repair deficiency complementation group 1 (ERCC1) locus. The ordered clone map has been obtained starting from a foundation of cosmid contigs assembled by automated fingerprinting and localized to the cytogenetic map by fluorescence in situ hybridization (FISH). Clonal continuity of the map has been achieved by binning and linking the premapped cosmid contigs by means of yeast artificial chromosomes (YACs). The map consists of a single contig composed of 169 YAC members (minimal spanning path of 18 YACs) linking 165 cosmid contigs. Eighty percent, or about 13.2 Mb of the entire region spanned by the map, has been resolved to the EcoRI restriction map level. Twenty-nine sequence-tagged sites associated with genetic markers or derived from FISH-mapped cosmids have been placed on the map. In addition to the ERCC1 gene area, the map includes the location of the creatine kinase muscle locus (CKM), imidazoledipetidase (PEPD), glucophosphate isomerase (GPI), myelin-associated glycoprotein (MAG), the apolipoprotein E and C (APOE and APOC) genes, and the ryanodine receptor (RYR1) gene. This type of map provides a source of continuously overlapping DNA segments at a level of resolution two orders of magnitude higher than that obtained using YACs alone. In addition, it provides ready-to-use reagents for detailed analyses at the gene level, FISH studies of chromosomal aberrations, and DNA sequencing.

Chromosome Mapping↗

PubMed1995

Predictors of short term clinical and angiographic outcome after coronary angioplasty for acute myocardial infarction.

UNLABELLED: Coronary angioplasty is an effective method to achieve myocardial reperfusion in acute myocardial infarction (AMI). We reviewed our experience in 132 patients (pts) who underwent percutaneous transluminal coronary angioplasty (PTCA) of a totally occluded infarct-related artery (IRA) within 24 h after the onset of symptoms (mean delay 10 +/- 7 h), in order to identify the predictors of primary success and of major complications. PTCA was successfully performed in 113 patients (86%). Failure without complications occurred in 12 patients (8.4%); untoward events (death and emergency CABG) occurred in seven patients (5.3%). Pts in the failure group were more likely to have cardiogenic shock (53 vs. 8.8%, P < .0005), longer time to reperfusion (15 +/- 6 vs. 9 +/- 6 h, P < .0005), lower ejection fraction (EF) (42 +/- 16 vs. 54 +/- 12%, P < .0005), multivessel disease (74 vs. 43%, P < .03), and a smaller IRA diameter (2.8 +/- 0.6 vs. 3.1 +/- 0.6 mm, P < .03). Sex, age, previous bypass surgery, previous thrombolytic treatment, IRA, and infarct location were similar in both groups. Absence of cardiogenic shock (P < .0001), decreasing time to reperfusion (P < .005) and increasing EF (P < .02) were independent predictors of successful PTCA. Presence of cardiogenic shock (P < .0001) and decreasing EF (< .05) were independent predictors of untoward events. Repeat angiography was performed 24 h after the procedure in the success group. Angiographic deterioration (stenosis > or = 50% and/or TIMI flow grade < or = 1) was present in 18 pts (16%), among whose 5 pts (4.4%) had re-occlusion of the IRA. Pts with early angiographic deterioration were more likely to have a lower IRA diameter (2.8 +/- 0.5 vs. 3.1 +/- 0.6 mm, P < .02). CONCLUSION: Emergency PTCA is an effective method for establishing reperfusion in AMI. Pts with high-risk baseline characteristics show the highest rate of untoward events, but are the most likely to benefit from aggressive reperfusion therapy.

Adult↗