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Biomedical subjects

J P Collins

Publications and source records attributed to J P Collins.

At least 19 recordsLinked to original sources
PubMed1998

Ureteropelvic junction disruption secondary to blunt trauma: excretory phase imaging (delayed films) should help prevent a missed diagnosis.

PURPOSE: Ureteropelvic junction disruption is a rare condition which is often diagnosed after some delay. The aim of this study is to examine the current status of this entity and to determine if improvements could be made in the diagnosis. MATERIALS AND METHODS: We evaluated 5 consecutive adult cases of ureteropelvic junction disruption secondary to blunt trauma and compared the findings to those reported in literature. RESULTS: The diagnosis was delayed by at least 24 hours in 4 of the 5 cases (80%). Compared to the literature, in which most delays in diagnosis were the result of genitourinary tract imaging being omitted, most of our delays (3 cases) were a result of the initial contrast enhanced spiral (helical) computerized tomography (CT) failing to provide the diagnosis. This failure occurred because of either absence of contrast extravasation (2 cases) or only subtle extravasation (1 case), which was not recognized by the radiologist. The delay in diagnosis resulted in added morbidity in all circumstances. CONCLUSIONS: Ureteropelvic junction disruption continues to be diagnosed late in a large proportion of cases. Absence of gross contrast extravasation on nephrogram phase scanning using spiral CT may not exclude a major injury of the ureteropelvic junction. Addition of delayed CT of the kidney 5 to 8 minutes or longer after contrast material injection (during the excretory phase) may increase the probability of extravasation being demonstrated and, thus, reduce the possibility of missing a ureteropelvic junction disruption.

Adult↗
PubMed1998

Implementation of image-guided large-core needle biopsy of the breast on a limited budget.

Image-guided large-core needle biopsy (LCNB) of the breast is becoming widely accepted as an accurate, minimally invasive and economical way to obtain a tissue diagnosis of breast lesions. However, much of this work has been done with expensive dedicated equipment, often favouring stereotaxic guidance. Image-guided LCNB was introduced to Middlemore Hospital based around existing inexpensive equipment, and stereotaxic or ultrasound guidance was chosen depending on which showed the lesion best. Multidisciplinary clinical, radiological and pathological assessment of each case was performed. The results of 213 biopsies (112 stereotaxic and 101 ultrasound guidance) are reported here. Malignancy was shown or suspected in 85 biopsies (40%). The absolute sensitivity for malignancy was 97% with complete sensitivity of 100%. The absolute specificity was 100% and the complete specificity 98.5%. Large-core needle biopsy can be successfully implemented in a large institution without investment in expensive equipment while maintaining high ratios of malignant/benign biopsies. Attention to technique and careful multidisciplinary review are important to the success of such a programme.

Biopsy, Needle↗
PubMed1996

Toward further reducing wound infections in cardiac operations.

BACKGROUND: Serious wound infections such as mediastinitis still occur at a rate of 0.8% to 2.0%, according to the most recently published cardiac operative series. METHODS: Data from careful surveillance for infection have been collected prospectively during a 4.5-year period on 1,717 patients who underwent cardiac operations performed under direct ultraviolet C radiation. RESULTS: The rate for mediastinitis was 0.23%, and for deep incisional infection without mediastinitis, 0.12%; these rates are significantly lower than those for eight of nine of the most recently published cardiac series. When our infection rates were stratified using the National Nosocomial Infection Surveillance risk index, they were also significantly lower in the most important risk categories than the corresponding stratified rates collected from the participating hospitals of the Centers for Disease Control and Prevention National Nosocomial Infection Surveillance system. CONCLUSIONS: Though we lack the proof that only a large, randomized study might provide, certainly, one possible explanation for our lower wound infection rate was the use of bactericidal ultraviolet C radiation during operation. This is a simple and effective means of minimizing operating room airborne bacteria as one possible source of these infections.

Aged↗
PubMed1996

Absence of serum prostate-specific antigen and loss of tissue immunoreactive prostatic markers in advanced prostatic adenocarcinoma after hormonal therapy: a report of two cases.

We report two cases of advanced prostatic adenocarcinoma (PA) showing complete loss of three tissue immunoreactive prostatic markers, ie, prostate-specific antigen (PSA), prostatic acid phosphatase (PAP), and Leu-7 (CD57), with absence of elevated serum PSA level, despite tumor progression after hormonal therapy with or without radiotherapy. The pretreatment serum PAP in the first case and serum PAP and PSA in the second case were elevated. In both cases, the prostatic adenocarcinoma in the initial transurethral resection specimens showed positive immunoreactivity with three prostatic markers. After treatment, in both cases, the serum PSA were undetectable, and tumor cell immunostaining for three prostatic markers was negative. In addition, the posttreatment tumors in both cases showed increased number of tumor cells with neuroendocrine differentiation in comparison those in the pretreatment tumors. Although early PA without elevated serum level of PSA is common, advanced PA with absence of elevated serum PSA, associated with presence of tissue immunoreactive prostatic markers are rare. This is the first report of advanced prostatic adenocarcinomas showing loss of tumor cell prostate-specific markers with absence of elevated serum PSA level after hormonal therapy despite tumor progression.

Adenocarcinoma↗
PubMed1996

Vascular myxolipoma ("angiomyxolipoma") of the spermatic cord.

We report a case of vascular myxolipoma of the spermatic cord occurring in a 32-year-old man. Clinically, the lesion was mobile and tender. Pathologically, the tumor was encapsulated and rubbery with a beige-yellow gelatinous cut surface. Microscopically, the lesion consisted of adipose tissue with extensive areas of myxoid change and an abundance of thin and thick-walled blood vessels. We consider this tumor a vascular type of myxolipoma and propose the term angiomyxolipoma. The lesion should be distinguished from liposarcoma and aggressive angiomyxoma, which have malignant or aggressive clinical course.

Adipose Tissue↗
PubMed1996

Smooth pursuit eye movements in the evaluation of famotidine adjunctive therapy of schizophrenia: a preliminary report.

Smooth pursuit eye movements (SPEM) are often abnormal in schizophrenic patients and have been proposed as a trait marker of the disorder. We explored the use of SPEM as an outcome measure in an open-label clinical trial of famotidine, an H-2 antagonist, in patients with schizophrenia; famotidine has been proposed as an adjunctive medication, particularly for negative symptoms. Prior studies using SPEM as an outcome measure have not found a significant effect with "typical" neuroleptic medication, and one study found greater SPEM dysfunction with clozapine treatment. In this study, 19 schizophrenic subjects were stabilized for at least 1 week on conventional neuroleptic medications and then administered oral famotidine, 100 mg daily, for an additional 3 weeks. SPEM and clinical measures were assessed. Whereas Brief Psychiatric Rating Scale (BPRS) and Schedule for Assessment of Negative Symptoms (SANS) scores decreased significantly with famotidine administration, there was no significant change in SPEM performance over the course of the study. Two subjects (11%) doubled their signal/noise ratio and maintained this increase after famotidine discontinuation, whereas three subjects (17%) approximately halved this ratio and returned to baseline after famotidine discontinuation. SPEM changes were not found to correlate significantly with changes in BPRS or SANS scores. These findings suggest that SPEM dysfunction reflects a "trait" rather than clinical "state" in schizophrenia, and changes in SPEM performance might not be expected always to parallel changes in clinical ratings.

Antipsychotic Agents↗
PubMed1996

A multi-format interdisciplinary final examination.

Limitations of the traditional final medical examination for the assessment of clinical competence led to such developments as simulated patients and the Objective Structured Clinical Examination (OSCE). An interdisciplinary OSCE incorporating simulated patients and involving nine disciplines was introduced into the final examination in the Auckland School of Medicine to supplement the written papers and the long case. Six-hundred and eight students were assessed over a 6-year period. Each of the three examination modes provided good discriminatory power. Significant correlations were found between the tests, but this does not mean one or more is redundant. Principal component analysis showed that a single significant factor accounted for over half the variance in the final assessment. This factor was equally weighted to the three examinations. A variety of evaluative methods are necessary to assess a student's competence and greater emphasis should be placed on those methods which encourage the learning of clinical skills and concurrently provide an appropriate mechanism for assessing them. The changes introduced have been supported by students and teachers and have fostered the learning of important clinical skills. Efforts to standardize the single long case have not overcome the criticisms surrounding its use, particularly in summative assessment.

Clinical Competence↗
PubMed1995

Ancestry of an isolated subspecies of salamander, Ambystoma tigrinum stebbinsi Lowe: the evolutionary significance of hybridization.

Most phylogenetic systematists assume speciation results in dichotomously branching phylogenies. Hybridization that gives rise to a new lineage can produce character homoplasty that might obscure a species' true history. We report the results of a restriction-enzyme analysis of mitochondrial DNA (mtDNA) variation in three tiger salamander subspecies (Ambystoma trigrinum mavortium, Ambystoma tigrinum nebulosum, and Ambystoma trigrinum stebbinsi) and compare the results to studies of morphological and allozymic variation in these taxa. Allozymically, A. t. mavortium and A. t. nebulosum share most of their genomes (although each has several unique alleles), yet color pattern and mtDNA haplotypes are distinct. Color pattern and allozyme data suggest that A. t. stebbinsi shares a common ancestor with A. t. mavortium, while the A. t. stebbinsi mtDNA haplotype is derived from an A. t. nebulosum haplotype. Thus, our data suggest that A. t. stebbinsi originated through hybridization between A. t. mavortium and A. t. nebulosum. That hybridization can produce recognizably distinct evolutionary entities has long been recognized for plants, but the evolutionary significance of hybridization in animals should be examined more closely. Conservation agencies must recognize that hybrids and hybrid taxa are not necessarily evolutionary "mistakes," and they might have significant importance in the production of natural biodiversity.

Animals↗
PubMed1995

A randomised study to compare the effect of the luteinising hormone releasing hormone (LHRH) analogue goserelin with or without tamoxifen in pre- and perimenopausal patients with advanced breast cancer.

The use of goserelin with or without tamoxifen was investigated in a randomised multicentre study involving 318 pre- and perimenopausal advanced breast cancer patients. With a median follow-up of 93 weeks, 31% of goserelin-treated patients had objective responses (UICC criteria) compared with 38% of goserelin plus tamoxifen-treated patients (P = 0.24). There was a modest benefit in favour of combination therapy in time to progression (P = 0.03) but not in survival (P = 0.25). Median follow-up for survival was 117.5 weeks. Median times for disease progression and survival were 23 and 127 weeks in the goserelin alone group and 28 and 140 weeks in the combination group, respectively. In 115 patients with skeletal metastases only, significant differences in favour of combination therapy were seen in response rate, time to progression and survival. Both treatments were well tolerated and no additional safety issues were associated with combination therapy.

Adult↗
PubMed1995

Famotidine adjunctive pharmacotherapy of schizophrenia: a case report.

Recent reports suggest some utility for famotidine, a histamine type 2 (H2) antagonist, in the treatment of schizophrenia. The current report describes a treatment-resistant patient with chronic undifferentiated schizophrenia whose most dramatic symptomatic improvements were temporarily related to the open-label addition of famotidine (40-100 mg/day) to conventional neuroleptic treatment (molindone 150-200 mg/day) over the course of approximately 10 months. During one 2-week interval, his symptoms were controlled with famotidine (40 mg/day) alone. The case suggests that some adjuvant efficacy exists for famotidine in at least some patients with schizophrenia. Placebo-controlled trials are needed to more fully evaluate the utility of famotidine in the treatment of schizophrenia.

Famotidine↗
PubMed1995

A structured panel interview and group exercise in the selection of medical students.

The selection of entrants for medical school, as now widely agreed, should include measurements of non-academic as well as academic attributes. The authors have developed a process to assess the personal attributes of applicants. This included a structured panel interview carried out twice on each applicant by independent interviewers and a group exercise in which several applicants were observed whilst discussing a problem. Training for interviewers took the form of a half-day interactive workshop. One hundred and forty-one school-leaving applicants completed the new assessment. No relationship was found between academic achievement as reflected by marks in a national examination and scores in the panel interview, the group exercise, or the school principal's report. However, significant intercorrelations were found between the panel interview, group exercise and school report. The results of this experience have encouraged the Auckland School to continue to explore methods to measure these attributes in a carefully controlled study.

Education, Medical, Undergraduate↗
PubMed1995

Entry to medical school: an audit of traditional selection requirements.

The major focus in the selection of entrants for medical school has traditionally been on academic achievement in school-leaving examinations in which certain science subjects are a requirement. A longitudinal study of 413 successful applicants was undertaken to determine the relationship of these admission criteria to subsequent performance. The findings support a correlation between overall marks in the school-leaving examination and the annual Grade Point Averages. Those students in the top quartile for marks showed a significant advantage in terms of achievement but only in the preclinical years. Despite the significant correlations no predictions could be made on the basis of overall marks. No correlation was found with levels of clinical competence during the ward clerkships or with the interdisciplinary objective structured clinical examination (OSCE) in the final examination. Marks in individual school-leaving examination subjects correlated with performance during different parts of the course but only those entrants in the top quartile for marks in physics and biology showed an advantage through to the clinical years. English marks were the least correlated and failed to confer an advantage in any year of the course. None of the correlations between school-leaving marks and grades in medical school exceeded 0.4. The predictive value of school-leaving examination marks therefore accounted for only 16% of the variance in subsequent examinations. Selection of medical students on the basis of academic criteria alone is inadequate and should be accompanied by assessment of personal qualities. This School no longer uses school-leaving marks as the primary selection instrument.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical Competence↗