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Biomedical subjects

J Beynon

Publications and source records attributed to J Beynon.

At least 73 records · Page 4Linked to original sources
PubMed1988

Transvaginal endosonography: a new method to study the anatomy of the lower urinary tract in urinary stress incontinence.

A new method to investigate the anatomy of the lower urinary tract in women is described. Direct ultrasound images of the bladder neck and proximal urethra were obtained using a vaginal endoprobe; the series comprised 100 women with a range of urinary symptoms. The technique was well tolerated by patients and there was no morbidity. Transvaginal endosonography is suitable for the assessment of many aspects of urinary incontinence.

Endoscopy↗
PubMed1988

Rectal endosonography, a new technique for the preoperative staging of rectal carcinoma.

Endosonography of the rectum is a new and exciting technique which is having an increasing impact on the surgical and radiological community and is likely to have two principal applications in patients with rectal cancer. Firstly in the preoperative staging of the disease it has been shown to provide an objective reproducible method of assessment allowing the more accurate planning of treatment whether purely surgical or including some form of adjuvant treatment. Secondly in the follow up of patients who have already had surgery or radiotherapy it may be possible to detect in particular extrarectal local reoccurence at an early and treatable stage. Initial results with this technique are extremely promising but further long term studies are now needed to see whether it will improve overall survival or decrease local recurrence.

Carcinoma↗
PubMed1988

The use of CA-50 radioimmunoassay inhibition test in the differential diagnosis of benign and malignant breast disease.

The role of the tumour marker CA-50 has been studied in the differential diagnosis of benign and malignant breast disease. Serum levels of CA-50 were determined by radioimmunoassay using a level of 17 units/ml as a cut-off. All 50 normal subjects and 22 of 24 patients (92%) with benign breast disease had CA-50 levels below 17 units/ml. By contrast, 15 of 36 patients (42%) with breast carcinoma had serum CA-50 levels above 17 units/ml (P less than 0.001). There was no clear correlation with tumour stage. The data suggest that CA-50 levels may help to differentiate benign and malignant diseases of the breast.

Adolescent↗
PubMed1987

Comparative organization of nitrogen fixation-specific genes from Azotobacter vinelandii and Klebsiella pneumoniae: DNA sequence of the nifUSV genes.

In the facultative anaerobe Klebsiella pneumoniae 17 nitrogen fixation-specific genes (nif genes) have been identified. Homologs to 12 of these genes have now been isolated from the aerobic diazotroph Azotobacter vinelandii. Comparative studies have indicated that these diverse microorganisms share striking similarities in the genetic organization of their nif genes and in the primary structure of their individual nif gene products. In this study the complete nucleotide sequence of the nifUSV gene clusters from both K. pneumoniae and A. vinelandii were determined. These genes are identically organized on their respective genomes, and the individual genes and their products exhibit a high degree of interspecies sequence homology.

Aerobiosis↗
PubMed1987

Preoperative staging of local invasion in rectal cancer using endoluminal ultrasound.

Digital examination is the most commonly used method of assessing local invasion in rectal cancer, but it is highly subjective and accuracy is related to surgical experience. The use of transrectal ultrasound in the preoperative staging of rectal cancer has been assessed in 51 patients with histologically proven rectal cancers. Results showed a high degree of correlation when compared with postoperative histopathology (r = 0.91, P less than 0.001). Invasion beyond the muscularis propria was predicted with a sensitivity of 97%, specificity of 92% and predictive value of 97%.

Carcinoma↗
PubMed1986

Endoluminal ultrasound in the assessment of local invasion in rectal cancer.

A new method for staging local invasion in rectal cancer has been assessed. Thirty-eight patients with primary rectal cancers have been examined pre-operatively with endoluminal rectal ultrasound and results compared with histological analysis of resected specimens in 33 cases. Three patients who also underwent laparotomy but not resection had good evidence of both stage T3 (1) and T4 (2) disease. The coefficient of correlation between ultrasonic and histological staging was 0.93 (P less than 0.001). Invasion beyond the muscularis propria was predicted with a sensitivity of 96 per cent, specificity of 92 per cent and a predictive value of 96 per cent.

Adult↗
PubMed1986

Pre-operative assessment of local invasion in rectal cancer: digital examination, endoluminal sonography or computed tomography?

Forty-four patients with primary rectal cancers and six patients with benign rectal lesions were examined pre-operatively digitally, with endorectal sonography (ELU) and also computed tomography (CT). Digital examination of the rectal cancers had an overall accuracy of 68 per cent and predicted invasion beyond the muscularis propria with a sensitivity of 68 per cent, specificity of 83 per cent, positive predictive value of 100 per cent and negative predictive value of 46 per cent. In comparison CT had an accuracy of 82 per cent, sensitivity of 86 per cent, specificity of 62 per cent, positive predictive value of 91 per cent and negative predictive value of 50 per cent. ELU was the most reliable indicator of local invasion in rectal cancer when compared with postoperative histopathology with an accuracy of 91 per cent, sensitivity of 94 per cent, specificity of 87 per cent, positive predictive value of 97 per cent and negative predictive value of 78 per cent.

Aged↗
PubMed1986

Endorectal sonography: laboratory and clinical experience in Bristol.

The normal echographic pattern produced by the colon and rectum has been investigated in vitro. Five basic ultrasonic layers or interfaces have clearly been identified; a first echogenic layer produced by the mucosa, then an echopoor layer representing the mucosa and muscularis mucosae, an echogenic layer which was submucosa, echopoor layer which was muscularis propria and an echogenic layer which was either pararectal fat or serosa. The effectiveness of endoluminal ultrasound (ELU) in the pre-operative staging of rectal cancer has been assessed in a group of 67 patients who were also, where possible, graded by digital examination and in some cases computer aided tomography (CT) (33 patients). Digital examination had an overall accuracy of 50% and could predict invasion beyond or confinement to the rectal with an accuracy of 64%. ELU is a highly accurate method for staging local invasion and when compared to post-operative histopathology had an overall correlation coefficient of 0.88 (p less than 0.001) (Rank Spearman). Our overall accuracy was 91% and it could predict invasion beyond the muscularis propria with a sensitivity of 96%, specificity of 94% and positive predictive value of 98%. In the cohort studied by both radiological techniques ELU was more accurate than CT where overall accuracy was 79%, sensitivity was 84%, specificity was 63% and the positive predictive value was 88%.

Humans↗
PubMed1986

The endosonic appearances of normal colon and rectum.

With the increasing use of transrectal sonography, accurate preoperative staging of rectal cancer requires correct identification of the normal ultrasonographic appearances of the colon and rectum. Fifteen rectal and colonic specimens have been studied in vitro to define the normal anatomy. Five distinct ultrasonic layers have been identified; a first echogenic layer that corresponds to the mucosa, a second echopoor layer made up of mucosa and muscularis mucosae, a third echogenic layer that is submucosa, a fourth echopoor layer that is muscularis propria, and a fifth echogenic layer made up of serosa and perirectal fat.

Colon↗