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Biomedical subjects

J Wylie

Publications and source records attributed to J Wylie.

At least 19 recordsLinked to original sources
PubMed2003

Association of transforming growth factor beta-1 single nucleotide polymorphisms with radiation-induced damage to normal tissues in breast cancer patients.

PURPOSE: To investigate whether transforming growth factor beta-1 (TGFbeta1) single nucleotide polymorphisms were associated with the susceptibility of breast cancer patients to severe radiation-induced normal tissue damage. MATERIALS AND METHODS: PCR-RFLP assays were performed for TGFbeta1 gene polymorphisms on DNA obtained from 103 breast cancer patients who received radiotherapy. The G-800A, C-509T, T+869C and G+915C polymorphic sites were examined, and genotype and allele frequencies of two subgroups of patients were calculated and compared. RESULTS: The less prevalent -509T and +869C alleles were significantly associated with a subgroup of patients who developed severe radiation-induced normal tissue fibrosis (n=15) when compared with those who did not (n=88) (odds ratio=3.4, p=0.0036, and 2.37, p=0.035, respectively). Furthermore, patients with the -509TT or +869CC genotypes were between seven and 15 times more likely to develop severe fibrosis. CONCLUSIONS: These findings imply a role for the -509T and +869C alleles in the pathobiological mechanisms underlying susceptibility to radiation-induced fibrosis. Their predictive value would be limited to patients who are -509TT or +869CC, but if "fibrosis-associated" polymorphic sites in other genes could be identified, it may be possible to detect fibrosis prone individuals before radiotherapy with greater certainty.

Alleles↗
PubMed2002

Interventional laser surgery: an effective surgical and diagnostic tool in oral precancer management.

Invasive oral squamous cell carcinomas (OSCCs) are often preceded by precancerous lesions, the management of which remains controversial, polarized between active surgical excision to try to prevent malignant change or more conservative, medical or observational techniques. In order to determine the efficacy of interventional CO2 laser surgery in oral precancer management, the records of 57 consecutive laser-treated patients presenting over a 4-year period, with histologically confirmed dysplastic lesions, were reviewed. Leukoplakias were the commonest clinical lesions (69%), whilst the floor of the mouth was the most frequent anatomical site (42%). Laser surgery successfully excised 55 precancerous lesions, 11 of which exhibited more severe dysplasia or neoplasia compared with initial biopsy. Postoperative scarring and morbidity were minimal. After surgery, patients were followed for between 1 and 44 months (mean 18 months). Of these patients, 76% remained disease-free, whilst 24% developed new dysplastic lesions at distinct or multiple sites, often exhibiting increased dysplasia. Of the patients experiencing recurrence, 7% developed OSCC, whilst a further 3.5% presented with other aerodigestive tract cancers. Neither initial lesion appearance nor histological diagnosis predicted clinical behaviour. Interventional laser surgery is thus advised, in contradistinction to conservative management of oral precancers, to facilitate efficacious, low-morbidity treatment and to establish definitive histological diagnosis. As a consequence of field change carcinogenesis, regular follow up of treated precancer patients is mandatory for effective tertiary prevention.

Adult↗
PubMed2002

Molecular characterization of the vanE gene cluster in vancomycin-resistant Enterococcus faecalis N00-410 isolated in Canada.

The vanE operon was characterized from Enterococcus faecalis N00-410 (MIC of vancomycin = 24 microg/ml). The organization of the vanE operon was identical to that of the vanC1 operon from Enterococcus gallinarum, with protein identities ranging from 46 to 63%. An open reading frame located downstream of the vanE operon showed significant homology to a number of integrase genes, all of which are located downstream of the chromosomal GMP synthase gene guaA.

Canada↗
PubMed2001

Tumor size and oxygenation are independent predictors of nodal diseases in patients with cervix cancer.

PURPOSE: To determine the relationships between tumor oxygenation and nodal stage in a prospective study of patients with cervix cancer, controlling for other prognostic factors. METHODS AND MATERIALS: Between 1994 and 1999, 128 eligible patients with cervix cancer were entered into a prospective study of tumor oxygenation assessed by Eppendorf oxygen electrode before primary radiation therapy. Oxygenation was evaluated using the proportion of pO(2) values < 5 mmHg (HP(5)), and tumors were classified as hypoxic if the HP(5) was > 50%. Patients were assigned to one of three groups: those with no imaging evidence of nodal (pelvic or para-aortic) or distant metastatic disease (N group; n = 67), those with equivocal findings (E group; n = 28), and those with nodal or distant metastatic disease (P group; n = 33). RESULTS: The proportion of hypoxic tumors in the P, E, and N groups were 67%, 50%, and 40%, respectively (p = 0.014), with median HP(5) values of 63%, 48%, and 36%, respectively (p = 0.0024). In a multivariate analysis including tumor size, stage, HP(5), and hemoglobin, it was found that tumor size and HP(5) were the only independently significant variables for the finding of metastatic disease (p = 0.009 and 0.017, respectively). CONCLUSION: In this patient population, there was a significantly increased risk of nodal or distant metastases in patients with hypoxic tumors, and this finding was independent of tumor size. These results are consistent with the hypothesis that tumor hypoxia is an adverse prognostic factor associated with selection for a metastatic phenotype.

Adult↗
PubMed2001

Methicillin-resistant Staphylococcus aureus: profiles oceans apart--Canadian and Saudi Arabian experiences.

Methicillin-resistant Staphylococcus aureus (MRSA), a pathogen which has increased over the past three decades, is responsible for nosocomial infections and adverse patient outcomes. It is a pathogen of global importance. Rates of patient colonization or infection vary greatly internationally. Lower rates have been observed in Canada and Saudi Arabia compared to the United States and United Kingdom. Although these lower rates may appear reassuring, the trend in MRSA observed in two capital cities, Winnipeg, Canada and Riyadh, Saudi Arabia are consistent with a widespread global increase in MRSA.

Canada↗
PubMed2000

Results of radical radiotherapy for recurrent endometrial cancer.

OBJECTIVES: The aims of this study were to determine the overall survival (OS) and local control (LC) achieved in patients developing a locoregional recurrence of endometrial carcinoma and to define those prognostic factors that predict for improved LC and OS. METHODS: Between 1984 and 1988, 958 women were referred to Princess Margaret Hospital (PMH) with a diagnosis of endometrial carcinoma. Of these, 58 were treated for recurrent disease with radical radiotherapy (RT). Forty-two were referred with recurrence and 16 relapsed during follow-up at PMH for their primary tumor. None had received prior RT. The majority (n = 49) were treated with combined external beam RT followed by an intracavitary cesium insertion. RESULTS: The median time to relapse from original diagnosis was 1.3 years (range 0.2-13.4 years). The actuarial 5- and 10-year OS was 53 and 41%, respectively. The respective results for LC were 65 and 62%. All end-points were measured from the time of relapse. The median total dose received was 81.5 Gy. Univariate analysis showed that favorable histological features at original diagnosis (<50% myometrial involvement, grade 1-2, P = 0.007) and Perez modified staging (P = 0.02) were significant predictors for OS. The Perez staging (P = 0.02) and size of recurrence (<2 cm versus >/=2 cm, P = 0.04) were predictors for LC. CONCLUSION: Patients with localized relapse of endometrial carcinoma in whom radical radiotherapy can be administered should be treated aggressively and may be cured in over half the cases treated. Pathological findings in the original surgical specimen, size of recurrent disease, and a modified vaginal carcinoma staging system are significant predictors of local pelvic control and survival.

Adult↗
PubMed1999

The local management of soft tissue sarcoma.

Soft tissue sarcomas (STS) are rare tumors arising from the connective tissues. STS can arise at any anatomic site, can demonstrate varied behavior and prognosis, and therefore present a formidable challenge in management. The local treatment of STS demands technical complexity in the application of diagnostic tools, including pathology and imaging, as well as treatment approaches, including surgical ablation and reconstruction, radiotherapy, and, in defined cases, chemotherapy. The understanding of the management of these lesions is profoundly dependent on the multidisciplinary setting, where experience has been gained and skills are available to increase the likelihood of a successful result. Several proven options are available for optimal local management, and the choice of approach depends on the prevailing practice and resource profile of the treating center. With modern approaches, the local control rate can be expected to be at least 90% for extremity lesions, which constitute the most common STS. The experience in other anatomic sites is less favorable as a result of a combination of late diagnosis, technically difficult access sites, and possibly less familiarity with these less common presentations. The disappointing results make it all the more important for patients to be referred to a multidisciplinary setting with experience in sarcoma management to maximize the chance of successful local outcome.

Amputation, Surgical↗
PubMed1995

A comparative study of two methods for obtaining the anteroposterior open mouth cervical view.

OBJECTIVE: To compare two methods of obtaining the anteroposterior (AP) open mouth view. DESIGN: Radiological evaluation of the occiput-C1/C1-C2 structures, as visualized on radiographs obtained using two different radiographic position set-ups. SETTING: The Anglo-European College of Chiropractic Clinic. PATIENTS: A total of 60 patients. Each method used on 30 patients. CRITERIA ASSESSED: Visualization of: (a) occiput-C1 joints, (b) atlantoaxial joints, (c) lateral masses C1 and (d) odontoid process. RESULTS: The visualization of the occiput-C1 joints was increased almost 100% using method 2. The atlantoaxial joints were seen in 7% more cases using method 2 and the lateral masses were seen in 10% more cases. The only structure seen more consistently using method 1 was the odontoid process, which was seen in 7% more cases using that method. CONCLUSION: This study shows that there is an easier and more consistent method of obtaining the AP open mouth view than that traditionally used in many institutions.

Atlanto-Axial Joint↗
PubMed1994

Persistent binocular diplopia following cataract surgery: aetiology and management.

We studied all patients referred to the orthoptic department with binocular diplopia following cataract surgery between January 1991 and June 1993. Persistence of diplopia for a minimum of 3 months after cataract surgery was required for inclusion in the study. Eighty-one patients (2% of all patients who underwent cataract surgery during this time) satisfied the entry criteria. The patients fell into two groups: non-traumatic and traumatic cataracts. Horizontal deviations were seen in 24 patients. Vertical deviations were seen in 8 patients and a combined horizontal and vertical deviation was seen in 49 patients. Fresnel prisms were used to manage the diplopia in 58 patients. Of these, 48 patients in the non-traumatic group regained binocular single vision with this prism while 10 in the traumatic group benefited. Mechanical and sensory causes are discussed.

Adolescent↗
PubMed1990

Clinical versus biochemical assessment in thyroxine replacement therapy: a retrospective study.

A retrospective audit of a thyroid clinic revealed that only 67% of clinical assessments of thyroid status in patients receiving thyroxine replacement therapy were correct. The identification of patients on excessive doses of thyroxine appears to be the most difficult by clinical assessment alone, only 10% of those patients with a suppressed TSH level being identified. This study emphasises the importance of thyroid function tests in the assessment of patients on thyroxine replacement.

Adult↗
PubMed1989

The prism bar--Prentice and frontal positions.

The prism cover test has been in use for many years for measuring ocular alignment. The measurements obtained are used for both calculating the amount of correction needed in strabismus surgery, and monitoring any change in ocular alignment with recovery from muscle imbalance. Variability may arise from its use in either the frontal position or the Prentice position. Most prism bars used in the United Kingdom are calibrated for use in the Prentice position. Inaccurate results arise when a prism bar is used in a position for which it is not calibrated. The theoretical calculation for adjusting measurements obtained in the frontal position with prisms calibrated for use in the Prentice position was assessed clinically. A new modified equation is proposed incorporating practical aspects of performing the prism cover test. A table of values is included to assist in determining the necessary adjustment, so allowing for a more reliable assessment.

Adolescent↗
PubMed1981

Retinoids and the prevention of cervical dysplasias.

Women with abnormal cytology were matched with normal control subjects for age, parity, ethnicity, and socioeconomic class and participated in a blind case-control study focused on the role of nutrition in cervical dysplasia. Sucrose gradient ultracentrifugation studies for determination of the presence and concentration of the binding proteins for retinol and retinoic acid were performed on colposcopic biopsy tissue specimens. The nutritional survey revealed statistically significant differences for vitamins A and C and beta carotene. Retinol binding protein was absent or minimally detectable and inversely related to the severity of the dysplasia. It is proposed that a double-blind clinical trial be conducted to evaluate whether retinoids may pharmacologically inhibit, arrest, or reverse cervical dysplasia.

Ascorbic Acid↗
PubMed1977

Some Rorschach data concerning suicide.

The Rorschachs of 59 effected suicides and 31 attempted suicides, all of which were collected within a period of 60 days prior to the critical event were categorized in terms of method used, and subjected to a computer scan to determine if any constellation of variables occurred with a greater frequency than in the protocols of three control groups, comprised of inpatient depressives, inpatient schizophrenics, and nonpatients. A constellation of 11 variables is reported, a composite of eight or more correctly identifies 75% of the effected group and 45% of the attempters while occurring with a relatively low frequency among controls. Data are also presented from a group of 33 records collected within five days after a suicidal attempt revealing that those records do not differ essentially from either of the two psychiatric control groups. The findings are discussed in terms of the problems of prediction, and in the context of the probable psychological structure of many suicide prone people.

Adolescent↗