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G McGreal

Publications and source records attributed to G McGreal.

18 recordsLinked to original sources
PubMed2005

Measurement of plasminogen activator system components in plasma and tumor tissue extracts obtained from patients with breast cancer: an EORTC Receptor and Biomarker Group collaboration.

The plasminogen activator (PA) system comprises the 2 serine proteases, urokinase PA (uPA) and tissue PA (tPA), the 2 serpin inhibitors, PAI-1 and PAI-2 and the uPA receptor (uPAR; CD87). High levels of uPA, PAI-1, uPA-PAI-1 complex and uPAR in breast cancer tissue are associated with poor prognosis, while high levels of tPA or PAI-2 correlate with good prognosis. In this study, pre-operative plasma levels of uPA, PAI-1, uPAR, tPA, uPA-PAI-1 complex, and tPA-PAI-1 complex were measured in patients with benign (n=103) and malignant breast disease (n=113) by immunoenzymatic assays (ELISA). While plasma antigen levels of uPA, PAI-1, uPA-PAI-1 complex and uPAR were not significantly different in the 2 groups, antigen levels of tPA and tPA-PAI-1 complex were significantly higher in patients with breast carcinoma compared to the control group. In plasma from the breast cancer patients, uPA levels correlated weakly but significantly with those of tPA (r=0.20, p=0.035) and uPAR (r=0.208, p=0.028). tPA levels correlated strongly with tPA-PAI-1 complex (r=0.972, p=0.0001) while uPA-PAI-1 levels were significantly associated with PAI-1 levels (r=0.534, p<0.0001), tPA levels (r=0.348, p=0.0003) and tPA-PAI-1 levels (r=0.356, p=0.002). However, no significant correlation was found between plasma and tumor tissue levels of uPA, PAI-1, uPA-PAI-1 complex, tPA or tPA-PAI-1. Our findings indicate that determination of these factors in plasma do not reflect their concentration in tumor tissue. Therefore, measurement of PA components in blood cannot be recommended for assessing prognosis in breast cancer.

Biomarkers, Tumor↗
PubMed2004

Overexpression of the Ets-1 transcription factor in human breast cancer.

The Ets family of transcription factors regulate expression of multiple genes involved in tumour progression. The aim of this study was to investigate the expression of Ets-1 in a large panel of human breast cancers and relate its levels to the parameters of tumour progression and metastasis. Using RT-PCR, Ets-1 mRNA was detected in 30 out of 42 (71%) fibroadenomas and 131 out of 179 (73%) primary breast carcinomas. Similarly, levels of Ets-1 mRNA were not significantly different in fibroadenomas and primary breast carcinomas. Using Western blotting, four forms of the Ets-1 protein were detected, that is, p33, p42, p51 and p52. Levels of both p51 and p52 but not p33 and p42 were present at significantly higher levels in the carcinomas compared to the fibroadenomas (for p51, P<0.007; for p52, P<0.02; Mann-Whitney U-test). Levels of p52, p51 and p33 correlated significantly with uPA protein levels (P<0.01), while only levels of p52 correlated significantly with HER-2/neu protein levels (P<0.01). Using immunohistochemistry, Ets-1 was found predominantly in tumour cells, but was also detected in some stromal cells surrounding tumour islands. We conclude that, while at the mRNA level, Ets-1 was found at similar levels in fibroadenomas and primary breast carcinomas, higher protein levels were detected in the cancers compared to the benign specimens. Since p52, p51 and p33 correlate with uPA levels, these forms of Ets-1 may play a role in breast cancer metastasis.

Biomarkers, Tumor↗
PubMed2004

Cyclooxygenase-2 expression in primary human colorectal cancers and bone marrow micrometastases.

BACKGROUND: Both the expressions of the inducible form of cyclooxygenase-2 and the presence of bone marrow micrometastases are poor prognostic markers in patients with colorectal carcinoma. AIMS: As cyclooxygenase-2 expression in these tumours is associated with increased metastatic potential in vitro, our objectives were to determine the relationship between cyclooxygenase-2 and haematogenous spread to bone marrow. PATIENTS AND METHODS: Thirty-two patients with resection of colorectal carcinoma were evaluated (median age: 69.5 years). Bone marrow was obtained from all patients from both iliac crests before manipulation of the primary tumour. The tumours were of varying stages at diagnosis (5 Dukes' A, 14 Dukes' B, 11 Dukes' C and 2 Dukes' D). Tumour sections were stained for cyclooxygenase-2 using the avidin-biotin immunohistochemical technique. Extent of staining was graded depending on the percentage of epithelial cells staining positive for cyclooxygenase-2. Micrometastases were detected by staining contaminant cytokeratin-18 positive cells in the bone marrow aspirates by either immunohistochemical (ARAAP) or immunological (flow cytometry) methods. Fisher's exact probability test was used to calculate statistical significance. RESULTS: Cyclooxygenase-2 expression in the primary tumour was detected in 72% of the patients. Twelve (38%) patients had bone marrow micrometastases detected by either immunohistochemistry or flow cytometry. Of the 12 patients who had bone marrow micrometastases, 8 tumours demonstrated increased expression of cyclooxygenase-2 protein (66.6%). In contrast, 9 out of the 20 (45%) patients in whom micrometastases were not detected expressed increased levels of cyclooxygenase-2 (P = 0.29). When dividing the patients into subgroups of localised (Dukes' A and B) versus disseminated (Dukes' C and D) disease, there was no further association between cyclooxygenase-2 expression and bone marrow micrometastases (P = 0.179 and 1.0). CONCLUSION: In this pilot study, there was no association between cyclooxygenase-2 expression and bone marrow micrometastases in patients with otherwise localised or disseminated disease.

Aged↗
PubMed2001

Minimally invasive, radioguided surgery for primary hyperparathyroidism.

BACKGROUND: Primary hyperparathyroidism affects 1 in 700 individuals in the United States. A single adenoma is responsible in over 85% of cases. Surgery remains the most effective treatment. This study was designed to assess the feasibility of minimally invasive radioguided parathyroidectomy (MIRP) with confirmation of excision by ex vivo radioactivity alone. METHODS: Seventy-five consecutive patients with primary hyperparathyroidism were prospectively studied. Following sestamibi scan, patients underwent unilateral neck exploration guided by a handheld gamma probe, which was also used to measure ex vivo radioactivity of excised tissue. RESULTS: The sestamibi scan was positive in 88% of the patients. A small incision (mean, 3.2+/-0.3 cm) was sufficient. Ectopic gland sites were localized in five patients with positive scans and single adenomas. Mean operative time was 48 minutes (range, 15-125 minutes), with shorter procedures after the initial 20 cases (mean, 24 vs. 72 minutes; P < .01). Radioguided parathyroidectomy was successful in 97%, with a mean follow-up of 11 months (range, 1-26 months). As noted previously, adenomatous parathyroid glands contained more than 20% of the background radioactivity. CONCLUSIONS: MIRP is a feasible alternative to bilateral dissection with the advantages of guided dissection and rapid confirmation, and may become the procedure of choice for primary hyperparathyroidism.

Adenoma↗
PubMed2001

Prospective evaluation of the morbidity of axillary clearance for breast cancer.

BACKGROUND: Axillary clearance, despite its morbidity, retains an essential role in the management of patients with breast cancer. The aim of this prospective study was to document the development of arm swelling and limitation of shoulder movement following complete axillary clearance. METHODS: One hundred patients who had axillary clearance to level III, for treatment of breast cancer, were followed prospectively for over 1 year. Arm volumes were measured using an optoelectronic volometer and shoulder movements with a goniometer. RESULTS: Ten patients had significant arm swelling at 1 year. The swelling was mild in eight and moderate in two. No patient developed severe swelling. Reduced arm movements were noted in the first week after operation but had returned to normal at 6 months. CONCLUSION: This study provided accurate documentation of the morbidity associated with axillary clearance, together with a reproducible method of arm volume measurement.

Adult↗
PubMed2001

Nasogastric intubation causes gastroesophageal reflux in patients undergoing elective laparotomy.

BACKGROUND: The routine use of nasogastric tubes in patients undergoing elective abdominal operation is associated with an increased incidence of postoperative fever, atelectasis, and pneumonia. Previous studies have shown that nasogastric tubes have no significant effect on the incidence of gastroesophageal reflux or on lower esophageal sphincter pressure in healthy volunteers. We hypothesized that nasogastric intubation in patients undergoing laparotomy reduces lower esophageal sphincter pressure and promotes gastroesophageal reflux in the perioperative period. METHODS: A prospective randomized case-control study was undertaken in which 15 consenting patients, admitted electively for bowel surgery, were randomized into 2 groups. Group 1 underwent nasogastric intubation after induction of anesthesia, and Group 2 did not. All patients had manometry and pH probes placed with the aid of endoscopic vision at the lower esophageal sphincter and distal esophagus, respectively. Nasogastric tubes, where present, were left on free drainage, and sphincter pressures and pH were recorded continuously during a 24-hour period. Data were analyzed with 1-way analysis of variance. RESULTS: The mean number of reflux episodes (defined as pH < 4) in the nasogastric tube group was 137 compared with a median of 8 episodes in the group managed without nasogastric tubes (P =.006). The median duration of the longest episode of reflux was 132 minutes in Group 1 and 1 minute in Group 2 (P =.001). A mean of 13.3 episodes of reflux lasted longer than 5 minutes in Group 1, with pH less than 4 for 37.4% of the 24 hours. This was in contrast to Group 2 where a mean of 0.13 episodes lasted longer than 5 minutes (P =.001) and pH less than 4 for 0.2% of total time (P =.001). The mean lower esophageal sphincter pressures were lower in Group 1. CONCLUSIONS. These findings demonstrate that patients undergoing elective laparotomy with routine nasogastric tube placement have significant gastroesophageal reflux in the perioperative period and a reduced ability to clear refluxed acid from the distal esophagus. Due to the associated risk of postoperative pulmonary complications, we recommend that nasogastric intubation be performed on a selective rather than routine basis.

Case-Control Studies↗
PubMed2001

Synchronous high-risk melanoma and lymphoid neoplasia.

Large population-based studies have shown a significant association between melanoma and lymphoid neoplasia, particularly non-Hodgkin's lymphoma (NHL) and chronic lymphocytic leukaemia (CLL), that is independent of any treatment received for the initial tumour. This study examines the presentation, diagnosis, treatment and progress of three patients who developed advanced melanoma concurrently with a lymphoid neoplasm (one NHL, two CLLs), in order to illustrate their association, discuss common aetiological factors and examine possible therapeutic options. As it is the melanoma rather than the lymphoid neoplasm that represents the bigger threat to overall survival, initial treatment should be targeted towards this cancer. However, because of the interplay between the diseases and the possible side-effects of the various treatments, the choice of adjuvant therapy requires careful consideration. Immunosuppression associated with chemotherapy may permit a more aggressive course for the melanoma, while locoregional radiotherapy is contraindicated following lymph node dissections. As immunotherapy is of benefit in the treatment of melanoma and has also been recently shown to be effective in the management of lymphoid neoplasia, we instituted interferon-alpha as adjuvant therapy for these patients, thereby utilizing a single agent to treat the dual pathologies. The three patients have now been followed-up for 6 months without evidence of disease recurrence or progression.

Aged↗
PubMed2001

Trichobezoar.

Explore the source record for details and available documents.

Bezoars↗
PubMed1999

High levels of tissue inhibitor of metalloproteinase-1 predict poor outcome in patients with breast cancer.

Studies from model systems suggest that matrix metalloproteinases (MMPs) are causally involved in tumor progression while tissue inhibitors of MMPs (TIMPs) prevent this progression. Here, we show that concentrations of TIMP-1 are significantly higher in breast carcinomas than in fibroadenomas. In primary breast cancers, TIMP-1 concentrations increased with increasing tumor size but showed an inverse relationship with estrogen receptor concentrations. In primary breast cancers also, TIMP-1 levels were weakly but significantly correlated with those for MMP-1, proMMP-2, active MMP-2, MMP-3 and proMMP-9. Contrary to what might be expected from published data on model systems, high concentrations of TIMP-1 predicted a poor outcome in patients with breast cancer. We conclude that in human breast cancer, endogenous TIMP-1 does not inhibit tumor progression but may enhance the process.

Biomarkers, Tumor↗
PubMed1993

c-myc oncogene expression: a marker for females at risk of breast carcinoma.

In an attempt to identify patients at risk of breast cancer, 9E 10 c-myc monoclonal antibody was used to detect the oncogene products in 64 breast tissue biopsies. There were 44 specimens of benign breast disorders: 21 from patients who developed subsequent breast cancer, and 23 from patients who did not. The remainder were malignant tumor biopsies from those who developed breast cancer. C-myc over-expression was identified in 12 (60%) of the breast carcinomas; it was also noted in 13 (62%) of the benign biopsies from patients who developed subsequent breast carcinoma. Expression was observed in only 3 (13%) controls--patients who did not develop cancer. A prospective study is now warranted to determine the clinical usefulness of our findings.

Antibodies, Monoclonal↗
PubMedDate not supplied

Management of patients undergoing splenectomy in an Irish teaching hospital: impact of guidelines.

INTRODUCTION: Overwhelming post-splenectomy infection (OPSI) has a 50-70% mortality rate and carries a lifetime risk for the asplenic patient. Specific British guidelines have been developed to reduce its incidence. AIMS: To determine whether British guidelines were being followed in our own institution and what impact they had on overwhelming post-splenectomy infection. METHODS: Retrospective chart review of 100 splenectomies performed by Department of Surgery, Beaumont Hospital from January 1990 to January 2000. RESULTS: Twenty per cent of patients were discharged without any recommended vaccinations. Prophylactic antibiotics were not prescribed in 53% of patients. Just 12% of charts document a verbal explanation of the complications and management of asplenia to the patient. Overall septic mortality was 12%, of whom 8% died in hospital and 4% after discharge. CONCLUSION: Management of the asplenic patient has improved but is far from complete. A central register of asplenic patients and national asplenic guidelines should be established in Ireland to ensure optimum patient care.

Adolescent↗
PubMedDate not supplied

A prospective comparison of pedal ergometry with conventional treadmill testing in the investigation of lower extremity pain.

BACKGROUND: Investigation of lower extremity pain is compromised by comorbid disorders that may interfere with conventional testing. AIMS: To compare pedal ergometry with conventional treadmill testing. METHODS: A prospective study was performed where patients presenting with a diagnosis of intermittent claudication were assessed by both methods of testing. RESULTS: Of 78 patients studied with both tests, no exercise-induced ankle pressure changes occurred in 26, two were unable to complete either test despite normal pressure measurements, while 24 had exercise-induced pressure drop detected by both tests. Of patients who completed pedal ergometry, 21 were unable to complete the treadmill test, 14 of whom had negative ergometry, while seven had a pressure drop detected by pedal ergometry. Three had pressure changes with pedal ergometry, but not with treadmill testing and two had pressure changes on the treadmill not reproduced by pedal ergometry. CONCLUSIONS: Pedal ergometer is more sensitive than treadmill testing in detecting arterial insufficiency, as indicated by a 20% or greater fall in ankle pressure, and more suitable in a subgroup of patients unable to tolerate conventional treadmill testing.

Blood Pressure↗
PubMedDate not supplied

The biomechanical evaluation of polyester as a tension band for the internal fixation of patellar fractures.

We use a braided polyester suture in place of cerclage wire in tension band fixations. The objective of this study was to test the biomechanical properties of this technique. Sixteen cadaveric patellae were fractured and repaired by modified tension band fixation. Eight were fixed using eighteen gauge stainless steel wire as a tension band and eight using braided polyester. All specimens were subjected to tensile testing. Polyester was 75.0% as strong as wire. For dynamic testing, the patellae of seven cadaveric knees were fractured and then fixed with polyester tension bands. These were mounted in a device capable of extending the knees from 90 degrees to neutral against an applied force. None of the fixations failed. Three of the specimens fixed using 18 gauge stainless steel wire were compared with three fixed using polyester over 2000 cycles of knee flexion and extension. Polyester performed as well as wire. We conclude that polyester is an acceptable alternative to wire in tension band fixation.

Biomechanical Phenomena↗
PubMedDate not supplied

47 years of phaeochromocytomas.

Thirty three patients with phaeochromocytomas had surgery in St. Vincent's Hospital between 1950 and 1997. 32 patients had hypertension, 32 had palpitations and 30 had excessive sweating. All patients had at least one of these cardinal symptoms. Diagnostic tests changed over this period. In the early cases the phentolamine test was used, later diagnosis was confirmed by measurement of urinary VMA and catecholamines. IVP, CT, ultrasound or MIBG scanning were used to locate the tumours. Before 1967, 3 of 17 patients died peri-operatively, 2 of these from strokes and one from pulmonary embolism. Since then, all patients have survived surgery. Four of the women had phaeochromocytomas diagnosed during pregnancy. Two of the 33 patients had tumours that were malignant, the remainder being benign. One patient has died from metastatic disease. This series illustrates the changing trends in the surgical management of phaeochromocytomas.

Adolescent↗