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Biomedical subjects

R D Harris

Publications and source records attributed to R D Harris.

At least 19 recordsLinked to original sources
PubMed2000

A randomized phase II trial comparing two different sequence combinations of autologous vaccine and human recombinant interferon gamma and human recombinant interferon alpha2B therapy in patients with metastatic renal cell carcinoma: clinical outcome and analysis of immunological parameters.

PURPOSE: The clinical observation of spontaneous regression in patients with renal cell carcinoma (RCC) and the response to various immunotherapeutic therapies strongly suggest a role for the host immune system in this disease. Prior studies showed that sequential administration of interferon (IFN) gamma and IFN alpha to RCC patients was safe. Clinical responses as well as immune changes in the peripheral blood mononuclear cell compartment were observed. Autologous tumor cell vaccines (AV) have also demonstrated activity in renal cell carcinoma. We hypothesize that the addition of AV to sequential IFN gamma and a therapy might improve the tumor-specific immune response by providing an appropriate source of antigen in the appropriate cytokine environment. To our knowledge, this is the first trial using AV combined with IFN alpha and IFN gamma. The purpose of this study was to evaluate the feasibility of manufacturing and administering (AV) from resected tumor samples, and administration of AV with combination IFN gamma and IFN alpha therapy. Finally, the impact on immunological parameters of these treatment options was assessed. MATERIALS AND METHODS: Patients with metastatic RCC were randomly assigned to receive AV plus bCG along with a sequential administration of IFN gamma and a either together or after initiation of vaccine. Toxicity and clinical responses were evaluated. Modulations of the immune system were investigated by analyzing phenotype, cytokine mRNA expression, T cell proliferation and cytotoxicity in the peripheral blood mononuclear cell compartment. RESULTS: Fourteen patients with metastatic renal cell carcinoma were enrolled in this study; 9 were available for response evaluation. In a 70 day period, 3 (33%) showed mixed responses, 5 (56%) stable disease and 1 (11%) progression of disease. Toxicities were consistent with previous clinical reports. In the flow-cytometry phenotype analysis, stimulation of distinct subsets of circulating T-lymphocytes and a decrease of CD8+ T cell subsets was demonstrated. T-cell proliferation to allogeneic tumor cell stimulation improved following treatment. IL-4 and IL-5 mRNA levels were reduced in all patients after treatment. Patients who responded to treatment did not produce any IL-4 mRNA at all, before or after treatment. CONCLUSIONS: AV with IFNgamma and IFNalpha therapy might induce a MHC class-mediated cytotoxic T lymphocyte (CTL) response. We suggest that adequate therapy might direct T cell response toward a Th1 type response. We hypothesize a state of improved immune readiness in patients who might eventually respond to immunotherapy.

Adult↗
PubMed2000

Clinical outcome in female patients with pelvic pain and normal pelvic US findings.

PURPOSE: To understand the clinical outcome in patients with pelvic pain and negative pelvic ultrasonographic (US) findings. MATERIALS AND METHODS: Data from 86 female patients with pelvic pain and normal pelvic US findings seen in a US section over a 15-month period were evaluated 6-21 months after US. Medical chart review follow-up was available in 86 patients, and telephone interview follow-up was conducted in 85 patients. We collected data on the outcome of pain; subsequent imaging, treatment, and surgery; and the duration of pain before US. RESULTS: Pelvic pain improved or resolved in 66 (77%) of the 86 patients. In the group with acute or subacute pain (duration </= 6 months), 62 (86%) of the 72 patients (19 with acute pain and 53 with subacute pain) had improvement or resolution of symptoms. In the group with chronic pain (duration > 6 months), seven (50%) of the 14 patients had improved symptoms. Further imaging (13 studies) was performed in nine patients: Twelve studies were normal, and one computed tomographic scan (1 month after the first US examination) showed diverticulitis. Eleven patients underwent 19 surgical procedures (endometrial sampling, hysteroscopy, laparoscopy, or hysterectomy). Four demonstrated clinically important disease (endometriosis and pelvic varices, endometriosis, adenomyosis, or pelvic adhesions). CONCLUSION: The majority of patients with pelvic pain and normal pelvic US findings had improvement or resolution of their symptoms, and those with acute or subacute pain were more likely to report improvement or resolution of pain than those with chronic pain. The yield of further imaging studies was low, and disease was identified in a minority of patients.

Acute Disease↗
PubMed2000

Prevalence and significance of heterogeneous testes revealed on sonography: ex vivo sonographic-pathologic correlation.

OBJECTIVE: Heterogeneous or mottled testes in middle-aged or elderly men are often encountered on sonography. To determine the prevalence, cause, and significance of this finding, we examined 50 testes (25 pairs) from autopsy specimens with sonography and gross and microscopic pathology. SUBJECTS AND METHODS: Testicles were obtained at autopsy from a series of 25 male cadavers (age range, 16-80 years; mean, 62 years). Eight subjects had a history of cancer. Ex vivo sonography was performed and two board-certified radiologists graded the testis by consensus as normal, heterogeneous, or "other abnormality" (cyst, dilated rete, echogenic focus, or halo). Microscopic pathology was obtained in all abnormal (sonographic or gross pathologic) testes. The severity of tubular sclerosis (atrophy) was graded on a scale of 0-3+ by a uropathologist. RESULTS; No testicular tumors were detected. Sonography revealed normal testes in 33 specimens, heterogeneous in seven specimens, and other in 10 specimens (one cyst, two dilated rete, three halos, and seven echogenic foci). Histology revealed that all seven cases of mottled or heterogeneous testis corresponded to extensive (grades 2 and 3) regions of tubular sclerosis (atrophy). A new sonographic finding of the "halo" was attributable to a thickened, adherent tunica albuginea. CONCLUSION: The prevalence of heterogeneous testes in this elderly population was 14% and represented seminiferous tubule atrophy and sclerosis. The prevalence of clinically occult testicular cancer or metastases in this autopsy subject group was nil. Older patients with a mottled or heterogeneous testis, normal color Doppler flow, and no palpable abnormality probably do not need sonographic follow-up.

Adolescent↗
PubMed1999

Integrated optical surface plasmon resonance immunoprobe for simazine detection.

This paper presents the detailed design and characterisation of a regenerable integrated optical surface plasmon resonance immunoprobe as a detector for the triazine herbicide simazine. A sensor design theoretically optimised for use in the aqueous environment is presented and its fabrication described. Experimental results on the sensitivity to changes in bulk refractive index of the analyte and on non-specific binding of ovalbumin are presented. Binding inhibition immunoassays were conducted for simazine and the lower limit of detection determined to be 0.16 microgram/l using anti-simazine IgG antibodies and 0.11 microgram/l using anti-simazine Fab fragments. A sample test cycle of 20 min was established.

Biosensing Techniques↗
PubMed1999

Prostate seed implant quality assessment using MR and CT image fusion.

PURPOSE: After a seed implant of the prostate, computerized tomography (CT) is ideal for determining seed distribution but soft tissue anatomy is frequently not well visualized. Magnetic resonance (MR) images soft tissue anatomy well but seed visualization is problematic. We describe a method of fusing CT and MR images to exploit the advantages of both of these modalities when assessing the quality of a prostate seed implant. METHODS AND MATERIALS: Eleven consecutive prostate seed implant patients were imaged with axial MR and CT scans. MR and CT images were fused in three dimensions using the Pinnacle 3.0 version of the ADAC treatment planning system. The urethra and bladder base were used to "line up" MR and CT image sets during image fusion. Alignment was accomplished using translation and rotation in the three ortho-normal planes. Accuracy of image fusion was evaluated by calculating the maximum deviation in millimeters between the center of the urethra on axial MR versus CT images. Implant quality was determined by comparing dosimetric results to previously set parameters. RESULTS: Image fusion was performed with a high degree of accuracy. When lining up the urethra and base of bladder, the maximum difference in axial position of the urethra between MR and CT averaged 2.5 mm (range 1.3-4.0 mm, SD 0.9 mm). By projecting CT-derived dose distributions over MR images of soft tissue structures, qualitative and quantitative evaluation of implant quality is straightforward. CONCLUSIONS: The image-fusion process we describe provides a sophisticated way of assessing the quality of a prostate seed implant. Commercial software makes the process time-efficient and available to any clinical practice with a high-quality treatment planning system. While we use MR to image soft tissue structures, the process could be used with any imaging modality that is able to visualize the prostatic urethra (e.g., ultrasound).

Brachytherapy↗
PubMed1999

Focal aneurysmal dilatation of subchorionic vessels simulating chorioangioma.

Subchorionic vascular aneurysms of the placenta are rare lesions and may present confusion with chorioangioma or focal mesenchymal dysplasia on sonography. To our knowledge, the findings of placental aneurysms have not been reported in the ultrasound literature. We present a case with detailed sonographic evaluation, including spectral and color Doppler and pathological analysis, that was mistaken for chorioangioma prenatally. Knowledge of this benign entity may allow the sonologist to recommend conservative management in similar cases.

Adult↗
PubMed1999

Consistency of retrospective triage decisions as a standardised instrument for audit.

OBJECTIVES: To determine the level of agreement between senior medical staff when asked to perform retrospective case note review of nursing triage decisions, both before and after development of a consensus approach. METHODS: Four medical reviewers independently allocated triage categories to 50 emergency department patients after review of their case notes. They were blind to the identity of the triage nurse and their triage categorisation. The process was repeated twice, firstly after agreement on a consensus approach and then using formal guidelines. RESULTS: Agreement between reviewers was initially fair to moderate (kappa = 0.27 to 0.53). This failed to improve after development of a consensus approach (kappa = 0.29 to 0.57). There was a trend towards better agreement when guidelines were used but agreement was still only moderate (kappa = 0.31 to 0.63). CONCLUSIONS: Audit of nurse triage categorisation by senior medical staff performing case note review has only fair to moderate consistency between reviewers. Use of this technique will result in frustration among those whose performance is being audited if they recognise inconsistency in the standard they are compared against.

Australia↗
PubMed1999

Interactive 3-dimensional computerized tomography reconstruction in evaluation of the living renal donor.

PURPOSE: We evaluated the efficacy of helical computerized tomography and a software program capable of 3-dimensional (D) reconstruction in assessment of the living renal donor. MATERIALS AND METHODS: A total of 20 consecutive patients (40 renal units) were evaluated using computer software and anatomical findings were assessed. Patient time and charges were compared with renal angiography and excretory urography (IVP). RESULTS: A total of 25 anomalies were identified in 21 kidneys using 3-D imaging. Accessory arteries were seen in 13 kidneys. Abnormal venous anatomy was found in 7 kidneys, including circumaortic renal veins in 2, multiple veins in 4 and a renal vein that drained into the gonadal vein in 1. Collecting system anomalies included a bifid pelvis and a duplicate ureter in 1 case each. Benign cysts were noted in 3 kidneys. Three patients were excluded from study due to persistent hypertension, death of the recipient before transplantation and bilateral aberrant vasculature, respectively. Intraoperative findings of the 17 kidneys removed for transplantation correlated with those demonstrated on 3-D reconstruction. Total preoperative imaging charges were decreased 50% compared to renal angiography and IVP, and the procedure related discomfort and potential morbidity were reduced significantly. Procedure time was reduced from 7 hours to 30 minutes with no resultant mandatory time off work or periprocedure restrictions in patient diet and/or activity. CONCLUSIONS: The enhanced 3-D computerized tomography reformation and reconstruction process appears to be as accurate as renal angiography for arterial anatomy, and more sensitive than renal angiography and IVP in evaluating venous and parenchymal anatomy. This software program provides superior and interactive imaging at substantially lower cost with minimal patient time, discomfort and morbidity.

Humans↗
PubMed1998

The Australian health system: continuity and change.

The health of Australians, with the exception of Aboriginals and Torres Strait Islanders, compares favourably with other industrialised nations. Since 1984, universal access for citizens to medical and public hospital services has been achieved under a national Health Insurance Scheme called Medicare, partially funded by a 1.4 percent levy on all taxpayers. Medicare found early widespread support from the electorate but continues to be buffeted by a minority coalition of some medical associations, private health insurers, and conservative "libertarian" politicians. Over the decade since its inception, Medicare has provided stability in maintaining total health costs around 8 percent of GDP. This has been largely due to capping hospital costs via Commonwealth-State agreements. Medicare has failed in the past five years to contain medical costs which have increased proportionally with increases in the medical workforce. This article examines the structure and performance of Medicare and its role within Australia's overall health system. Benefits of a universal access insurance program are outlined together with challenges associated with inequities in health status, geography, aging of the population, burgeoning technology, ideological diversity, and an economic climate requiring cost containment and favouring privatisation and the role of the market. It can be concluded that, despite these challenges, universal access to health care is here to stay. Australia's Medicare program has become popular with the electorate.

Australia↗
PubMed1998

Intervillous blood flow in patients with missed abortion.

AIM: Analysis of the color Doppler features of intervillous flow in cases of missed abortion, and their comparison with the findings in normal pregnancy. METHODS: Transvaginal color and pulsed Doppler was used in the analysis of 38 patients with missed abortion and 40 patients with normal pregnancy. The gestational age ranged from 6 to 11 weeks. Repeated analysis of variance was used to compare the groups. RESULTS: Two types of Doppler signals were detected in the intervillous space: pulsatile and continuous. Impedance in the intervillous space of both groups did not change significantly with the gestational age. For the group with missed abortion, the mean resistance index (RI) was 0.37 +/- 0.03 and pulsatility index (PI) 0.75 +/- 0.07. For the control group, the mean RI was 0.36 +/- 0.02 and PI 0. 72 +/- 0.04. The differences in RI and PI for all gestational age groups and between the two patient groups were not statistically significant. With advancing gestation, continuous, venous-like signal became stronger and randomly dispersed throughout the placenta. Peak flow velocity values obtained from both groups did not change significantly with gestational age, nor between the two groups. Conclusion. The new generation of sensitive Doppler units can detect the intervillous flow as a continuous progressive process at 6-11 weeks of gestation. The vascular resistance in the intervillous space does not change in cases of missed abortion.

Abortion, Missed↗
PubMed1997

Accuracy of prenatal sonography for detecting circumvallate placenta.

OBJECTIVE: We determined the accuracy of prenatal sonography for detecting placental circumvallation, a placental abnormality associated with increased fetal morbidity and mortality. MATERIALS AND METHODS: We analyzed 62 healthy pregnant (range, 18-36 weeks) patients with focused placental sonography for detection of morphologic abnormality using the published criteria for circumvallate placenta (irregular edge, uplifted margin, or placental sheet or shelf). Placental marginal sonograms were taken at 30 degrees intervals around the entire placental margin. Five experienced sonologists who were unaware of the pathologic findings independently reviewed the placental images and graded the placentas from 1 (definitely normal) to 5 (definitely circumvallate). Receiver operating characteristic (ROC) curves and area under the ROC curve were calculated for each reader. Gross and microscopic pathology was used as the gold standard for all cases. RESULTS: In the 62 patients, sonography revealed 49 normal placentas (79%), 12 partially circumvallate placentas (19%), and one completely circumvallate placenta (2%). ROC curves for the reviewers resulted in values for area under the curve ranging from .39 to .58. The sonologist who achieved the highest value for the area under the curve classified the 13 cases of proven circumvallation as one case of definite circumvallation, four cases as uncertain or equivocal, and eight cases as probably or definitely normal placentas. Of the normal placentas, 35% were graded as probably or definitely circumvallate by at least one sonologist. All sonologists misgraded the case of complete circumvallation as normal. CONCLUSION: Focused placental sonograms interpreted by experienced sonologists fail to detect the placental edge abnormality in most cases of circumvallation. In our study, 17 of 49 normal placentas were diagnosed as probably or definitely circumvallate by one or more observers. Our sonologists' interpretations of sonograms showed that complete circumvallation was difficult to assess. Although our study had a limited number of patients, the accuracy of sonography of the placenta for revealing circumvallation appears to be limited.

Case-Control Studies↗
PubMed1997

Managing successful construction and renovation projects.

If you are the lead person during a project, it is your responsibility to follow-up on every detail and task involved to guarantee overall success. Team members look to you as the example and as the communicator. Although other people may fail to accomplish their tasks, you must have the ability and energy to push the issue to completion without losing your cool or throwing your hands up. Projects usually require the coordination of multiple issues, tasks, and personnel. The process can be rewarding, or it can be your worst nightmare. Make it fun, but keep it organized. Communicate properly, and design each project process to fit the project needs.

Building Codes↗
PubMed1996

Sonography of the placenta with emphasis on pathological correlation.

The placenta is a most interesting but unfortunately often ignored and misunderstood organ. Included in its many functions are fetal oxygenation and nutrition as well as a myriad of endocrinological contributions and protein synthesis. The sonologist is strongly encouraged to study this amazing structure with ultrasound because significant pathology afflicts the placenta, often before affecting the fetus. Placental abnormalities, therefore, can be an "early warning system" for fetal problems. Recognition of clinically important lesions (abruption, accreta) as well as important anatomical variants (intervillous thrombosis, septal cyst) is crucial for the physician who performs and interprets prenatal ultrasound. This article discusses the common abnormalities of the placenta and highlights some correlative pathological processes, which will serve to enhance the reader's understanding of sonographic findings. A practical approach is presented with respect to assessment of the hypoechoic lesion, placental infarction, thick placenta, placenta previa, abruption, placenta accreta, and placental tumors.

Female↗
PubMed1996

Tissue-shrinkage correction factor in the calculation of prostate cancer volume.

Many studies that have calculated prostate cancer volumes from microscopic slides have used correction factors, ranging from 1.22 to 1.5, to compensate for tissue shrinkage during tissue processing. We undertook a study to measure tissue shrinkage directly because our experience suggested less shrinkage than that reported by others. Ten prostatectomy specimens were processed in a uniform manner. Multiple identical linear measurements were taken at four stages of processing: in the fresh state, following fixation, following processing, and from the microscopic slide. Linear shrinkage following fixation was minimal (4.1%) but increased to 14.5% following tissue processing. With rehydration and expansion on the flotation bath, tissues swelled so that net linear tissue shrinkage was 4.3%, and net volumetric tissue shrinkage was 12.4%, which translates into a correction factor for tissue shrinkage of 1.14. The following variables had no statistically significant effect on shrinkage: concentration of formalin, whole-mount versus quadrant sections, thickness of tissue slices, length of time in the alcohol dehydration steps, and temperature of the flotation bath over a range of 35 to 45 degrees C. This study suggests that (a) tissue-shrinkage correction factors that have been used in some previous studies may not be applicable for all laboratories because of interlaboratory variations in tissue-processing procedures or differences in measuring shrinkage; and (b) some calculated tumor volumes that have been used for prognostic thresholds may be high because of inflated tissue-shrinkage correction factors.

Humans↗