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J R Young

Publications and source records attributed to J R Young.

At least 55 records · Page 3Linked to original sources
PubMed1995

Health-related quality of life: measurement and clinical application. A workshop report.

The process of measuring health-related quality of life (HQL) in oncology is reviewed and the role of these results in clinical practice and clinical trials is discussed. It is determined that comparisons of HQL measurement instruments are needed to clarify which questionnaires are preferable in particular populations or situations. "Calibration" data are also needed, to help explain the meaning of HQL scores and to link them to external reality. In phase III clinical trials, HQL assessment is most important in trials involving disease sites and stages with a poor prognosis and when comparing treatments not expected to affect survival.

Bias↗
PubMed1994

Monomeric homologue of mammalian CD28 is expressed on chicken T cells.

A mAb recognizing a 40- to 44-kDa monomeric molecule on the surface of chicken T cells was used to screen a cDNA expression library made from Con A-stimulated chicken spleen cells. The sequence of the cDNA obtained encoded a molecule having 50% amino acid sequence identity with mammalian CD28, but the cysteine residue involved in the inter-chain bridge of the mammalian CD28 homodimer was not conserved in the chicken sequence. The molecule produced in transfected COS-7 cells was also recognized by another mAb that had previously been thought to recognize an avian homologue of CD2. The sequence data establish that this molecule is a homologue of mammalian CD28 in the strict evolutionary sense.

Amino Acid Sequence↗
PubMed1994

Research on health-related quality of life: dissemination into practical applications.

Strategies and processes for the effective dissemination and diffusion of research findings on health-related quality of life (HQL) into practical applications were explored at a workshop held in Montreal in April, 1994. A conceptual model for dissemination and diffusion of evidence about HQL was used to identify five different target groups: HQL assessors, policy makers, planners of clinical trials, developers of clinical practice guidelines, and those at the level of patient-practitioner clinical decision making. A framework designed to facilitate the translation of fundamental research knowledge into effective action was then used as a starting point for discussions about priorities for research on HQL. The most important problem identified at the workshop was how best to strike an appropriate balance between priorities deemed to be important to those directly involved in HQL research, and priorities deemed to be important to potential users of the results of HQL research?

Algorithms↗
PubMed1994

Electrophoretic karyotyping is a sensitive epidemiological tool for studying Trypanosoma evansi infections.

Thirty-six isolates of trypanozoon trypanosomes collected from camels in Northern Kenya during the dry season sporadic infections of 1986 and during the wet season epidemic infections of 1987 were identified as Trypanosoma evansi by the homogeneity of their kinetoplast DNA minicircles. Although the minicircles of all the isolates were indistinguishable, polymorphism in chromosome-sized DNA molecules detected by electrophoresis was extensive. The isolates could be grouped into eight distinct electrophoretic karyotypes which could be distinguished from three additional karyotypes identified among earlier T. evansi isolates. In one camel herd with a long history of trypanocide application, which was continued during the present study, all isolates bar one belonged to one karyotype group. From a second herd, in which trypanosomosis management was by individual treatment of proven parasitaemic cases, isolates with diverse karyotypes were obtained. Some of the karyotypes identified during the dry season sporadic infections were re-isolated in the subsequent wet season epidemic. These observations indicate that distinguishing T. evansi isolates by molecular electrophoretic karyotypes is more discriminating than kDNA analysis. Observations of karyotype patterns recurring in isolates from herds kept under chemoprophylaxis could help in the identification of drug-resistant parasites.

Animals↗
PubMed1994

Ultrasound demonstration of small breast cancers detected by mammographic screening.

The visibility on ultrasound (US) of 79 screen-detected small breast cancers was studied retrospectively. Overall visibility on US was 61% (48/79). Cancers presenting as microcalcification alone on mammography were rarely demonstrated (1 of 26 tumours). However, the US visibility of cancers with other mammographic appearances was 88.7% (47/53). The majority of cancers were impalpable but were demonstrated using free-hand ultrasound. All cancers visible on US appeared as hypoechoic masses with three quarters of these showing distal attenuation. US is useful in assessing and localizing small cancers detected by mammographic screening.

Breast Neoplasms↗
PubMed1994

Assessment of the role of ultrasound in the differentiation of radial scars and stellate carcinomas of the breast.

Radial scars are benign lesions of the breast which cannot be reliably distinguished from carcinoma by their mammographic appearances alone [1,2]. The present wisdom is that all such lesions should be biopsied [2]. We report a retrospective study carried out to assess whether there are any ultrasound imaging features that may be useful in differentiating radial scars from carcinoma and so reduce the need for excision biopsy. Over a period of 44 months between 1988 and 1992, 530 patients underwent surgery for abnormalities detected by routine mammographic screening. Of the 191 benign lesions excised, 24 were radial scars. Ultrasound images of 21 radial scars were mixed with an equal number of images of histologically proven carcinomas that had similar mammographic appearances. These images were reviewed 'blind' by a single radiologist. We were unable to find any ultrasound appearances sufficiently specific to radial scars to allow confident exclusion of malignancy. We therefore endorse the current practice of biopsying all mammographically detected stellate lesions.

Adenocarcinoma↗
PubMed1994

Ultrasound-guided compression repair of postcatheterization pseudoaneurysms: results of treatment in one hundred cases.

PURPOSE: The purpose of this report is to describe the indications, technique, and results for ultrasound-guided compression repair (UGCR) of postcatheterization pseudoaneurysms at a large medical center in which catheter-based diagnostic and interventional procedures are frequently used. METHODS: We reviewed the initial series of 100 consecutive patients who underwent UGCR in our noninvasive vascular laboratory from May 1991 through August 1992. Nearly all (n = 95) of these pseudoaneurysms involved the common femoral artery or its major branches, and each was manually compressed with a 5 MHz linear transducer for 10-minute intervals until the pseudoaneurysm was completely occluded or the procedure was considered to be a failure. RESULTS: UCGR was immediately successful in 94 patients, including 30 (86%) of 35 patients who were receiving anticoagulants and 64 (98%) of the 65 who were not (p = 0.019). The average compression time to achieve occlusion was 33 minutes (range 10 to 120 minutes), but was nearly twice as long (51 minutes) for pseudoaneurysms that had been present for more than 14 days. There were no related complications, but recurrent pseudoaneurysms occurred in six (20%) of 30 patients who continued to receive formal anticoagulation, compared with only four (6%) of 64 who did not (p = 0.074). Eight of the 10 recurrences were discovered within 24 hours after primary UGCR, but two others presented at 16 and 35 days, respectively. Eight recurrent lesions were corrected by repeat UGCR, whereas the remaining two required surgical repair. CONCLUSIONS: UGCR provides a reliable alternative to surgical treatment for postcatheterization pseudoaneurysms. Adequate follow-up is important, however, especially in patients for whom continued anticoagulation is necessary.

Aged↗
PubMed1994

Linkage mapping and partial sequencing of 10 cDNA loci in the chicken.

Ten cDNA clones derived from chicken spleen cell mRNA have been partially sequenced and the genes which encode the mRNAs have been located within the linkage map of the chicken genome. The sequences of five of these clones show strong homology to known mammalian genes, the remainder show little homology to sequence present in the current databases. Interestingly, one of these clones appears to be the chicken homologue of the mammalian peptide transporter gene TAP2 and is located within the major histocompatibility complex. Two other clones are homologous to genes involved in protein synthesis and these are tightly linked in chickens, as in mice. These results suggest that partial sequencing and mapping of clones from selective cDNA libraries may be an efficient way of adding candidate genes to the chicken linkage map and that on a local scale there may be some conservation of grouping of genes between chickens and mammalian species.

ATP-Binding Cassette Transporters↗
PubMed1993

Screening for breast cancer detects tumours at an earlier biological stage.

Between August 1988 and July 1990, 17,678 women in the Gateshead, Sunderland, South Tyneside and Durham districts attended the national breast screening programme. A total of 131 cancers were detected. The morphology of cancers detected by screening was compared with that of tumours in 71 patients presenting clinically in the same period. Screen-detected cancers included a higher proportion of tumours of more favourable histological grade and type, were smaller in size and had less axillary lymph node involvement than those detected clinically. Survival was predicted from the Nottingham Prognostic Index. Patients with screen-detected cancer had an expected survival advantage (95 per cent confidence interval) of 26.5 (12.3-40.6) per cent at 5 years, 26.5 (11.8-41.2) per cent at 10 years and 29.1 (14.5-43.7) per cent at 15 years. This survival advantage in screened patients expected at 5, 10 and 15 years is consistent with the 30 per cent reduction in mortality rate demonstrated in the Health Insurance Plan study and the Swedish two counties trial.

Breast Neoplasms↗
PubMed1993

Genome analysis of Theileria parva.

Recent technological developments in the field of genome analyses have advanced our knowledge of the structures of prokaryotic and eukoryotic genomes. Examples of these range from small bacterial genomes, such as Escherichia coli, to the more complex genomes of Caenorhabditis elegans, Drosophila, humans and mouse. Here, Subhash Morzona and John Young review developments in mapping the genome of on economically important protozoan parasite o f cattle, Theileria parva. This map provides a framework for more detailed analysis of the genome structure o f this organism. The methodologies developed in constructing the map also have application to the mapping of other protozoan genomes.

Journal Article↗
PubMed1993

Recommendations for training in vascular medicine. American College of Cardiology Peripheral Vascular Disease Committee.

Each trainee in vascular medicine must be eligible for the board certification examination of the American Board of Internal Medicine or its equivalent. Training faculty, preferably at least two members, should meet the qualifications and training requirements described in this report. They must be dedicated, effective teachers and should spend most of their time in research, education and patient care related to peripheral vascular diseases. A curriculum of training should be established. Faculty experts in related specialties and in the related basic sciences should be available for teaching. The institution should have a fully equipped noninvasive vascular laboratory and areas where catheter revascularization techniques and vascular surgery are performed. The period of training should not be less than 1 year, preferably continuous.

Cardiology↗
PubMed1993

Nonoperative treatment of superficial femoral artery disease: long-term follow-up.

PURPOSE: Between 1977 and 1991, 405 patients with atherosclerotic occlusive disease of the superficial femoral artery underwent clinical as well as noninvasive laboratory evaluation and were recommended for nonoperative treatment. METHODS: Limbs with uncorrected aortoiliac occlusive disease, aneurysmal degeneration, or previous femoropopliteal bypass were excluded, leaving 568 involved extremities. Complete follow-up, which forms the basis for this report, was available in 377 patients (93%) with 520 limbs (93%). Patients were monitored for a minimum period of 2 years (range, 24 to 164 months; median, 86 months). During the surveillance period 45 limbs (8.6%) in 42 patients (11.1%) required arterial intervention. This entailed operation in 39 cases and endovascular treatment in six cases. With use of life-table analysis, the risk for intervention was found to be 11% at 5 years and 14% at 10 years. A total of 14 limbs (2.7%) in 14 patients (3.7%) ultimately required major limb amputation, either after failed bypass (8 patients) or as a primary procedure (6 patients). RESULTS: Analysis of risk factors revealed that female sex (p = 0.04), chronic renal failure (p = 0.0001), diabetes mellitus (p = 0.0011), history of contralateral femoropopliteal bypass (p = 0.0005), level of disease (p = 0.003), and entry ankle/brachial index less than 0.50 (p = 0.004) were associated with an increased risk over time for intervention. Other factors, including age, current or prior smoking history, hypertension, and the presence of coronary artery disease or cerebrovascular disease failed to reach statistical significance. CONCLUSIONS: These data support the continued conservative approach to surgery for patients with superficial femoral artery occlusive disease without limb-threatening symptoms. Patients with multilevel disease, lower ankle/brachial index, a history of contralateral femoropopliteal bypass, chronic kidney failure, or diabetes mellitus are at increased risk and should be monitored more closely.

Adult↗
PubMed1993

The incidence of deep venous thrombosis in patients undergoing abdominal aortic aneurysm resection.

PURPOSE: Fifty consecutive patients undergoing abdominal aortic aneurysm resection were studied prospectively for the presence of deep venous thrombosis (DVT) after surgery. METHODS: Bilateral venography was performed 5 days after surgery in all patients. There were 42 men and 8 women, with a mean age of 70 years (range 60 to 83 years). No patients received DVT prophylaxis before surgery. RESULTS: Nine (18%) of 50 patients had a venogram positive for acute DVT. Nine (21%) of 42 men and none of eight women had DVT. Six patients had DVT in the left leg and three patients in the right leg. No patients had symptoms to suggest DVT. Seven (78%) of the nine patients with DVT had thrombi in the calf veins and two patients (22%) had thrombi in the more proximal venous segments, representing 14% and 4% of the entire series, respectively. No clinically evident pulmonary emboli were observed. CONCLUSIONS: Eighteen percent of 50 consecutive patients undergoing abdominal aortic aneurysm resection had DVT. Because of this high incidence, a study should be undertaken to determine whether DVT prophylaxis can lower the incidence of DVT after abdominal aortic aneurysm resection.

Aged↗