A 275 basepair fragment at the 5' end of the interleukin 2 gene enhances expression from a heterologous promoter in response to signals from the T cell antigen receptor.

Using a transient transfection assay, we have defined the sequences required for the activation of the IL-2 gene in response to signals from the T cell antigen receptor. To do so we have transfected the human T cell line Jurkat with hybrid DNA constructs in which fragments from the IL-2 gene are linked to an indicator gene. The indicator gene product, as well as IL-2 production from the endogenous IL-2 gene were assayed after activation of the transfected Jurkat cells by various stimuli. We have demonstrated that a 275 bp fragment stretching from 52 to 326 bp upstream of the IL-2 gene transcription initiation site is required for expression of the linked indicator gene. This IL-2 gene fragment has several of the characteristics of a transcriptional enhancer element, in that it functions in both orientations and will enhance the expression from the promoter of an unrelated gene. Such enhancement occurred only after activation of Jurkat cells through the T cell antigen receptor. More specifically, this 275 bp fragment activated the expression of a linked gene after binding of a monoclonal antibody to the Jurkat T cell antigen receptor in the presence of PMA. In addition, calcium ionophore, which circumvents antigen receptor binding in T cell activation, induced the expression of the linked gene through this 275 bp sequence, in the presence of PMA. Finally, in a mutant Jurkat cell line lacking T3/antigen receptor complexes at the cell surface, no expression due to the IL-2 5' flanking region was seen after exposure to antibody to the T cell antigen receptor plus PMA or to PHA plus PMA. In contrast, calcium ionophore plus PMA did induce the expression of a linked gene through the IL-2 5' flanking region in the mutant Jurkat cell line. The responsiveness of the transfected hybrid genes containing the IL-2 regulatory region paralleled the expression of the endogenous IL-2 gene, as determined by IL-2 bioassays. We conclude that the 275 bp IL-2 sequence (-326 to -52 bp) is a target for the signal pathway originating at the T cell antigen receptor. Definition of this 275 bp target sequence should now permit the isolation of the molecules that bind to and activate the IL-2 gene.

Interaction of a liver-specific nuclear factor with the fibrinogen and alpha 1-antitrypsin promoters.

The orderly and sequential activation of genes during development is hypothesized to be related to the selective expression of groups of regulatory proteins acting primarily at the level of transcription. A nuclear protein was found in hepatocytes, but not other cell types, that binds to a sequence required for hepatocyte-specific transcription of the gene for the beta chain of fibrinogen. This protein, hepatocyte nuclear factor 1 (HNF1), also interacts with homologous sequences required for optimal promoter function of the genes for the alpha chain of fibrinogen and alpha 1-antitrypsin. The promoter or enhancer regions for several viral and cellular genes not expressed in the liver did not compete for this binding. The restricted expression of HNF1 and its selective interaction with the control regions of several liver-specific genes indicate that it is involved in developmentally regulated gene expression in the liver.

The adenovirus major late transcription factor activates the rat gamma-fibrinogen promoter.

The major late transcription factor (MLTF) is a 46-kilodalton polypeptide that specifically binds to and activates transcription from the major late promoter of adenovirus. The presence of this promoter-specific transcription factor in uninfected HeLa cell extracts suggests that MLTF is also involved in the transcription of cellular genes. This report demonstrates that MLTF specifically stimulates transcription of the rat gamma-fibrinogen gene through a high-affinity binding site. Stimulation of transcription by MLTF was not dependent on the exact position of the MLTF binding site with respect either to the transcription initiation site or to adjacent promoter elements. These results suggest that one of the cellular functions of MLTF is to control gamma-fibrinogen gene expression.

Sp1, a CAAT-binding factor, and the adenovirus major late promoter transcription factor interact with functional regions of the gamma-fibrinogen promoter.

To study the factors which influence the coordinately and developmentally regulated expression of the three adjacent fibrinogen genes, we have defined the functional regions of the gamma-fibrinogen promoter and the proteins which bind to them. Using a series of 5' and internal deletion mutations, we found that sequences between 88 and 43 base pairs (bp) upstream of the gamma-fibrinogen transcription initiation site functioned in cis to direct properly initiated mRNA accumulation in transfected hepatocytes. The efficient function of these sequences was highly distance dependent, since transcriptional activity decreased by 92% when they were moved 32 bp upstream of the TATA box. We demonstrated that two known and one putative transcriptional factors interacted with this 47-bp sequence. The transcription factor Sp1 interacted with sequences between -51 and -46 as demonstrated by protection from DNase I digestion with the purified protein. Directly adjacent to the Sp1 site, between nucleotides -66 and -53, there was a sequence which bound a CAAT-binding factor. Finally, sequences just 5' to the CAAT factor-binding site interacted with the adenovirus major late transcriptional factor as previously demonstrated. Internal deletion mutations which disrupt these interactions diminished the activity of the promoter in vivo. One consequence of the interaction of these proteins is that a bend is placed in the DNA at or near their sites of interaction.

High-resolution detection of loss of heterozygosity of dinucleotide microsatellite markers.

Dinucleotide microsatellite markers are frequently investigated to study inheritance, genetic stability, and allele frequency distribution in a wide variety of genetic disorders. Previous studies have encountered significant problems regarding resolution and detection of dinucleotide, microsatellites. In this study, a useful method to investigate loss of heterozygosity (LOH) of dinucleotide microsatellite markers is described that involves the use of nondenaturing (Spreadex) submerged gel electrophoresis and SYBR Green I nucleic acid staining. This method omits the gel casting step and the use of hazardous radioactive materials frequently used in many microsatellite studies that employ polyacrylamide gel nucleic acid denaturation analysis. Using this method, 62 patients' paired tumor and normal samples were investigated to detect allele deletions in a region of chromosome 7q31.1, which is believed to harbor a tumor suppressor gene. Interpretable results were obtained in all cases. These results were compared to those attained using ABI Prism Genetic Analyzer 310 and Gene-Scan. There were no discrepancies in results obtained between the two assays. The Spreadex system is cheap, does not require larger equipment costs, and may prove to be a useful system for high-throughput investigation of microsatellites. It may have diagnostic significance and also prove useful if applied to population-based genomic screening and linkage analysis.

Electron arc irradiation of the postmastectomy chest wall: clinical results.

BACKGROUND AND PURPOSE: Since 1980 electron arc irradiation of the postmastectomy chest wall has been the preferred technique for patients with advanced breast cancer at our institution. Here we report the results of this technique in 140 consecutive patients treated from 1980 to 1993. MATERIALS AND METHODS: Thoracic computerized tomography was used to determine internal mammary lymph node depth and chest wall thickness, and for computerized dosimetry calculations. Total doses of 45-50 Gy in 5 to 5 1/2 weeks were delivered to the chest wall and internal mammary lymph nodes via electron arc and, in most cases, supraclavicular and axillary nodes were treated with a matching photon field. Patients were assessed for acute and late radiation changes, local and distant control of disease, and survival. Patients had a minimum follow-up of 1 year after completion of radiation treatment, and a mean follow up interval of 49 months and a median of 33 months. All patients had advanced disease: T stages 1, 2, 3, and 4 represented 21%, 39%, 21% and 19% of the study population, with a mean number of positive axillary lymph nodes of 6.5 (range, 0-29). Analysis was performed according to adjuvant status (no residual disease, n = 90), residual disease (positive margin, n = 15, and primary radiation, n = 2), or recurrent disease (n = 33). RESULTS: Acute radiation reactions were generally mild and self limiting. A total of 26% of patients developed moist desquamation, and 32% had brisk erythema. Actuarial 5 year local-regional control, freedom from distant failure, and cause-specific survival was 91%, 64%, and 75% in the adjuvant group; 84%, 50%, and 53% in the residual disease group; and 63%, 34%, and 32% in the recurrent disease group, respectively. In univariate Cox regressions, the number of positive lymph nodes was predictive for local failure in the adjuvant group (P = 0.037). Chronic complications were minimal with 11% of patients having arm edema, 17% hyperpigmentation, and 13% telangectasia formation. CONCLUSION: These data demonstrate that local-regional control with electron are therapy of the postmastectomy chest wall is comparable to photon techniques. Acute radiation reactions are well tolerated and mostly of minor extent. A previous report demonstrated a significant reduction in the dose-volume relationship of the lung using the electron arc compared with two photon techniques. Consequently, with careful attention to treatment planning and dosimetry, electron arc therapy of the postmastectomy chest wall is safe and effective. The radiation dose to heart and lung is minimized without compromise on local control.

Detection of sporadic cases of Norwalk-like virus (NLV) and astrovirus infection in a single Irish hospital from 1996 to 1998.

BACKGROUND: 'Norwalk-like viruses' (NLV) and astroviruses are recognised as the most important etiologic agents of viral gastroenteritis, excluding rotaviruses. However, neither of these two groups of viruses is routinely screened for in Irish hospital laboratories. OBJECTIVE: The objective of this study was to examine faeces collected from patients with non-bacterial, non-rotaviral gastroenteritis and examine if NLVs and astroviruses could be identified as the causative agents of the illness. STUDY DESIGN: Faecal specimens were collected from a single Irish hospital from February 1996 to June 1998. Three hundred and sixty samples were tested for the presence of NLVs using newly designed inosine-containing degenerate primers. Two hundred and three faecal specimens from paediatric patients were screened for the presence of astroviruses. RESULTS: the results of the screening study were that 29 (8%) specimens were found to be positive for NLV by reverse transcription polymerase chain reaction (RT-PCR) and 15 (7%) specimens from paediatric patients were found to be positive for astroviruses. Genotyping of the NLV-positive samples determined that four of the isolates were from genotype I (G1) and 25 were G2. The G2 positive specimens were further subtyped by oligonucleotide probing and the majority (n = 21) were found to be subtype P2-B, with four isolates being typed as P2-A. No P1-B isolates were found. CONCLUSIONS: This is the first report of detection of sporadic cases of NLV and astrovirus in Ireland. The results obtained highlight the need for continued surveillance of these viruses and the development of rapid detection systems for use in clinical laboratories.

Transcriptional gene expression profiles of oesophageal adenocarcinoma and normal oesophageal tissues.

The molecular events associated with the development of adenocarcinoma of the oesophagus are not well understood. Gene expression associated with oesophageal adenocarcinoma was investigated using a cDNA array containing 1,176 human cancer-associated genes. Approximately 59% of the genes were expressed at detectable levels with 15 genes (1.3%) exhibiting differential (> 2.5-fold) expression in either normal oesophagus or adenocarcinoma tissue. Nine genes were up-regulated in oesophageal adenocarcinoma tissue (matrix metalloproteinase 11 (MMP11), ornithine decarboxylase (ODC), cytokeratins 8 and 18, integrin alpha 3 (ITGA3), integrin alpha 6 (ITGA6), BIGH3 (transforming growth factor beta-induced), beta-catenin and CDC25B (M-phase inducer phosphatase 2)). Six genes were down-regulated in adenocarcinoma tissue (cytokeratin 4, plasminogen activator inhibitor 2 (PAI-2), interleukin 1 receptor antagonist (IRAP), cytokeratin 13/15/17, MAD and retinoic acid receptor gamma 1 (RARG)). Many of these differentially expressed genes influence cell-cell adhesion, cell-extracellular matrix and composition, transcriptional activation and cell cycle progression and are likely to contribute to development of oesophageal adenocarcinoma.

Ineffectiveness of methylprednisolone in the treatment of pulmonary dysfunction after cardiopulmonary bypass.

Fifty consecutive adults undergoing elective cardiac surgery with cardiopulmonary bypass received a single dose of methylprednisolone (30 mg/kg) at the time of anesthesia. The results were compared with those in the immediately preceding fifty adult patients who underwent elective cardiac surgery and who did not receive corticosteroids. The age, sex, and weight of the patient, mortality, nature of the lesions treated surgically, bypass time, smoking history, physiologic evidence of preexisting lung disease, preoperative New York Heart Association class, preoperative left ventricular end diastolic pressure, incidence and duration of the postoperative low cardiac output syndrome, postoperative arrhythmias, operative and postoperative blood loss and postoperative hours of respiratory support, dynamic lung-thorax compliance, alveolar arterial oxygen gradient, fraction of wasted ventilation, and incidence of tracheostomy were tabulated and statistically contrasted. The two groups were comparable relative to all preoperative factors, except for a slightly higher end diastolic pressure in the patients who received steroids. Methylprednisolone given at the time of anesthesia was associated with a higher intraoperative blood loss, a higher incidence of low cardiac output syndrome, and an increased requirement for postoperative mechanical ventilation. As bypass time approached three hours, the proportion of patients requiring prolonged support in both groups became similar. It was concluded that pretreatment with methylprednisolone in massive doses had an overall adverse cardiopulmonary effect.

Rotavirus survival and stability in foods as determined by an optimised plaque assay procedure.

Tissue culture adapted rotavirus strains were propagated in MA104 and CaCo2 cells using standard cell culture procedures. The progress of infection was monitored by examining for a cytopathic effect, and for the presence of viral RNA in the tissue culture supernatant as determined by a guanidinium-based method. Subsequently, an effective plaque assay for rotavirus was developed using MA104 cells by optimising the adsorption time (2 h) and the levels of fetal calf serum (2.5%) in the overlay medium. Tragacanth gum was used in the overlay medium to immobilize the virus, and plaques were subsequently stained with 1% crystal violet. Using this optimised plaque assay, the survival of rotavirus following exposure to heat and UV irradiation was evaluated by enumerating the clear plaques. It was shown that 60 degrees C for 10 min was sufficient to reduce the viral titer by at least 7 logs, and 50 mJ of UV irradiation was sufficient to reduce the initial viral titer by > 2.5 logs. This optimised plaque assay was also used to determine the survival and stability of rotavirus from a range of experimentally contaminated foods including fruit juice, formula milk and lettuce.

Exercise hemodynamic performance of the pulmonary autograft following the Ross procedure.

BACKGROUND AND AIMS OF THE STUDY: The Ross procedure, in which the aortic valve is replaced with the patient's own pulmonary valve (pulmonary autograft), is considered an excellent alternative for younger patients requiring elective aortic valve replacement. Although resting pulmonary autograft hemodynamics are excellent, exercise hemodynamic data are lacking. The study aim was to measure the hemodynamic performance of the pulmonary autograft with exercise Doppler echocardiography (DE). METHODS: Twenty-four Ross procedure patients (20 males, four females; mean age 46 +/- 11 years) were studied at 25 +/- 14 months after aortic valve replacement with a pulmonary autograft. Patients had baseline supine DE to measure the maximum velocity (Vmax), and the peak and mean pressure gradient across the pulmonary autograft. Effective orifice area was calculated from the continuity equation and indexed to body surface area (EOAi). Patients then underwent symptom-limited upright bicycle exercise with supine DE repeated immediately on stopping exercise. For comparison, 10 normal controls (age 41 +/-10 years) and five mechanical aortic valve patients (mean age 55 +/- 10 years) were studied. RESULTS: At rest: Ross procedure patients had similar Vmax (1.2 +/- 0.2 m/s), peak gradient (6 +/- 2 mmHg), mean gradient (4 +/- 1 mmHg) and EOAi (1.7 +/- 0.4 cm2/m2) to those of normal controls. Mechanical-valve patients had significantly higher Vmax (2.5 +/- 0.2 m/s, p <0.001), peak gradient (25 +/- 4 mmHg, p <0.001) and mean gradient (14 +/- 3 mmHg, p <0.001) than Ross patients and normal controls. At exercise: Ross procedure patients had similar Vmax (1.8 +/- 0.4 m/s versus 2.1 +/- 0.2, p = NS), peak gradient (14 +/- 6 mmHg versus 17 +/- 4, p = NS) and mean gradient (8 +/- 4 mmHg versus 10 +/- 2, p = NS) to normal controls, with no significant change in EOAi. Mechanical-valve patients had significantly higher Vmax (3.4 +/- 0.3, p <0.001), peak gradient (48 +/- 7 mmHg, p <0.001) and mean gradient (30 +/- 5 mmHg, p <0.001) than Ross patients and normal controls. CONCLUSIONS: Aortic valve replacement using the Ross procedure provides excellent hemodynamic results at rest and on exercise, with DE parameters indistinguishable from those of normal controls. This study provides further support for the use of the Ross procedure as a preferred method of aortic valve replacement in younger patients.

Human neutrophil granule cationic protein CAP37 is a specific macrophage chemotaxin that shares homology with inflammatory proteinases.

Cationic antimicrobial protein CAP37 (Mr = 37 kD) is derived from the azurophilic granules of human PMN. In vitro and in vivo studies demonstrate that CAP37 is a novel monocyte-specific chemoattractant. The N-terminal amino acid sequence of CAP37 shares significant homology with a number of inflammatory molecules with protease activity including elastase and cathepsin G. However, substitutions in the catalytic triad (serine for a histidine at position 41 and glycine for a serine at position 175), may account for its lack of serine protease activity. A full length cDNA for CAP37 was identified in an HL60 cDNA library screened with oligonucleotide probes designed from the N-terminal amino acid sequence. Sequencing of the cDNA reveals a protein of 225 amino acids with significant nucleotide homology to cathepsin G and human neutrophil elastase.

Rotavirus gastroenteritis among paediatric patients at Tralee general hospital.

Rotavirus infection among paediatric patients in Tralee general hospital was monitored over 4 years (1994 - 1998). A total of 2,319 specimens from gastroenteritis patients less than 7 years old were tested by latex agglutination assay, of which 203 (8.75%) were deemed positive. An inverse correlation was observed between age and susceptibility to infection, with the very young (under 2 years) most frequently infected. The virus was almost equally distributed among males (53%) and females (47%) testing positive for rotavirus. A distinctive early Spring peak of infection was evident annually, although the largest peak was identified in December 1997. This correlated with a significant change in circulating genotype as determined by RT-PCR based genotyping analysis of 45 rotavirus samples. In 1997, rotavirus accounted for 64% of all identified paediatric enteric agents at Tralee General for which an infectious agent could be identified. The average hospital stay was 3.2 days, and the direct hospital costs for rotavirus associated gastroenteritis was estimated at pounds sterling 31,232 per annum.

Purification and characterization of two aminopeptidases from guinea-pig small-intestinal mucosa. Cavian intestinal tripeptide hydrolases.

Two electrophoretically distinct cytosolic peptide hydrolases from guinea-pig small-intestinal mucosa have been highly purified by a six-step procedure comprising extraction from mucosal homogenate, ammonium sulphate fractionation, DEAE-cellulose chromatography, chromatofocusing, calcium phosphate chromatography and Sephadex G-100 gel filtration. They have similar apparent molecular masses as determined by gel filtration (Mr = 68 000) or by sodium dodecyl sulphate gel electrophoresis (Mr = 72 000). Both are aminopeptidases with optimum activity at pH 7.6. They are strongly inhibited by p-hydroxymercuribenzoate, o-phenanthroline and bestatin. Although both hydrolyse some dipeptides they have a distinctive kinetic preference for tripeptides composed of aromatic or non-polar residues. Their affinities for some tripeptides are particularly high and also the hydrolysis of some substrates exhibits biphasic kinetics. These two aminotripeptidases are similar but they can be differentiated from each other and from a number of other aminopeptidases.

Physical mapping of the CXC chemokine locus on human chromosome 4.

A physical map of the CXC chemokine locus on chromosome 4 has been constructed by PCR analysis and PFGE mapping of YAC clones. The genes for IL8, GRO1, PPBP, PF4, SCYB5 (ENA-78) and SCYB6 (GCP-2) have been co-localized on a 335-kb genomic fragment. The GRO2 and GRO3 genes did not map within this region and based on analysis of a YAC contig overlapping IL8 we speculate that GRO2 and GRO3 map downstream of this region. We have also assigned the novel CXC chemokine gene, SCYB9B (alias H174/betaR1) to chromosome 4q21, upstream and within 12 kb of INP10. Like INP10 and MIG, INP10 and SCYB9B are arranged in a head to tail manner. The chromosomal arrangement of these genes appears to reflect the evolution of this multigene family and supports the theory that it arose by gene duplication.

An evaluation of the cuff characteristics and incidence of laryngeal complications using a new nasotracheal tube in prolonged intubations.

A series of 1,187 nasotracheal intubations, carried out from January 1973 to December, 1975, used a new tube. The design included a smooth tip, a cuff with a large area of contact, low pressure and a high residual volume, and a radiopaque line which is easily visible on chest X-ray. A secondary irrigating lumen opening distal to the cuff provides closed-system irrigation, measurement of airway pressures, and sampling of tracheal gases. In the 811 intubated nontracheostomized patients who survived, the overall incidence of significant laryngeal damage was 1%. In patients intubated in excess of 10 days the damage incidence was 10%, and we suggest that tracheostomy should be carried out at this time. No patients suffered from any known permanent laryngeal damage.

Carcinoid tumors of the gastrointestinal tract.

The charts of 135 patients with gastrointestinal carcinoid tumors diagnosed over a 22-year period at 2 hospitals are reviewed and the clinical and pathological aspects discussed. Carcinoids occur most commonly in the appendix, jejunoileum, and rectum. Those smaller than 1 cm in diameter provide evidence of malignant potential only occasionally; lesions in the 1-1.9 cm range do this quite variably, and tumors 2 cm and larger are almost always invasive or metastatic or both. All gastrointestinal carcinoids except those of the appendix enlarge, invade, and metastasize predictably if given sufficient time. Most carcinoids except those of the rectum have already been adequately treated surgically when diagnosed by the pathologist. Local excision is effective treatment for noninvasive rectal carcinoids smaller than 2 cm in diameter, but those that have invaded or grown to 2 cm should undergo more radical resection. In general, gastrointestinal carcinoids carry better prognoses than do adenocarcinomata, and even in the presence of distant metastases long-term survival occurs in a significant number of patients. The frequent concomitance of associated malignant diseases accounts for as many or more deaths in these patients than the carcinoids themselves.