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Biomedical subjects

J R Anderson

Publications and source records attributed to J R Anderson.

At least 163 records · Page 9Linked to original sources
PubMed1995

Apolipoprotein E type epsilon 4 allele frequency is not increased in patients with sporadic inclusion-body myositis.

The apolipoprotein E genotype was determined for 11 patients with sporadic inclusion-body myositis. Seven cases had the genotype epsilon 3/epsilon 3, the other four cases, epsilon 3/epsilon 4. The frequency of the epsilon 4 allele in this group of patients (0.182) was not significantly increased compared with elderly controls (0.147; n = 58), in contrast to Alzheimer's disease in which there was a significant increase (0.328; n = 67). The epsilon 2 allele was not found in any of the 11 sporadic inclusion-body myositis patients and its frequency was decreased in Alzheimer's disease. Despite certain pathological similarities that exist between inclusion body myositis and Alzheimer's disease, their association with particular apolipoprotein E genotypes is distinct.

Aged↗
PubMed1995

Laparoscopy in the management of patients with cancer of the gastric cardia and oesophagus.

The role of laparoscopy in determining suitability for resection was prospectively evaluated in 244 patients with cancer of the gastric cardia and oesophagus. Laparoscopy enabled detection of inoperable disease in 92 patients (38 per cent), several of whom had more than one contraindication to surgery. Hepatic metastases (n = 75, 31 per cent), extensive peritoneal (n = 25, 10 per cent) or lymph node involvement (n = 5, 2 per cent) and direct invasion of the liver or colon (n = 5, 2 per cent) were considered contraindications to surgery. Laparoscopy was poorly tolerated in a further 11 (5 per cent) patients, who were not considered suitable for resection. Extra-abdominal metastatic disease was detected in 17 patients who appeared normal at laparoscopy, and a further six patients refused surgery. The remaining 118 patients underwent laparotomy with a view to resection which was successful in 85 (72 per cent). Laparoscopy thus prevented ill-advised laparotomy in 103 patients (42 per cent), either because of extensive intra-abdominal disease or poor tolerance to anaesthesia. Laparoscopy may be a valuable investigation when used to assess the feasibility of resection.

Adenocarcinoma↗
PubMed1995

Symptomatic outcome 1 year after laparoscopic and minilaparotomy cholecystectomy: a randomized trial.

In a randomized controlled trial, 299 patients were sent a symptoms questionnaire 1 year after laparoscopic (n = 151) or minilaparotomy (n = 148) cholecystectomy for symptomatic cholelithiasis. The response rate to the questionnaire from contactable patients was 86 per cent. In both groups, at least 90 per cent of patients reported that their symptoms were improved, and at least 93 per cent rated the success of their operation as 'excellent', 'good', or 'fair'. However, over half the patients reported abdominal pain, a quarter reported flatulence, and a quarter dyspepsia. The only difference between treatment groups was that a higher proportion of patients who underwent minilaparotomy reported heartburn (35 per cent versus 19 per cent, P = 0.005). Patients who reported a 'poor' outcome were more likely to have suffered a postoperative complication, had lower quality of life scores, and higher anxiety and depression scores. Both laparoscopic and minilaparotomy cholecystectomy result in symptomatic benefit in at least 90 per cent of patients with symptomatic cholelithiasis.

Abdominal Pain↗
PubMed1995

Steroid hormone receptor content and lymph node status in endometrial cancer.

The purpose of this study was to correlate the steroid hormone receptor status in endometrial adenocarcinoma with tumor metastasis to the pelvic and para-aortic lymph nodes, and with other known prognostic variables which influence survival. Tumor samples from 85 patients with endometrioid adenocarcinoma, or adenocarcinoma with squamous differentiation of the endometrium who underwent complete surgical staging, were assayed for cytoplasmic steroid hormone receptors using a dextran-coated charcoal technique. Steroid hormone receptor content was correlated to lymph node status, along with other prognostic variables, such as patient's age, depth of myometrial invasion, tumor grade, and pelvic cytology. By univariate analysis, the likelihood of nodal involvement was associated with younger age and poorly differentiated tumors. Multivariate analysis revealed that age, tumor grade, and myometrial involvement added significant independent prognostic information. Estrogen or progesterone receptor content did not add independent prognostic information concerning lymph node status once other factors were controlled. Knowledge of estrogen and progesterone receptor binding status in adenocarcinoma of the uterus does not replace the prognostic information imparted by careful sampling of lymph nodes.

Adenocarcinoma↗
PubMed1995

Radiographic evaluation of the complications of long bone allografts.

PURPOSE: To study the long-term results of long bone allografts in patients with benign and malignant bone tumors. MATERIAL AND METHODS: Forty patients for whom full clinical and radiological information was held were investigated in order to assess the overall incidence of complications including fractures, nonunion, hardware problems, infections, and bone resorption. RESULTS: There were four deaths; four more patients had distant metastases and one patient had a recurrent chondrosarcoma. Seventeen patients (42%) had either no complications (nine patients) or only minor ones (eight patients). Eleven patients (27%) sustained fractures of either their allograft (eight patients) or of their hardware (three patients). Hardware problems occurred in nine patients (22.5%), six of whom had serious problems requiring revision. The majority of the fractures and hardware problems occurred in younger male patients (82%). Infection occurred in five patients (12.5%), two of whom required revision, while two cases were superficial. Dissolution of the allograft occurred in 12 patients (30%), 7 of whom required removal of the allograft. Ten of these 12 patients were female. CONCLUSION: The long-term survival of long bone allografts is not as good as generally reported if an adequate follow-up time period is used. Most of the fractures and hardware problems occurred in the younger active male patients, whose activities should probably be curtailed. Resorption of the allograft is another serious complication which appears to occur mainly in female patients and could possibly be controlled by chemotherapy.

Adult↗
PubMed1995

Genital tract infections in women.

The future holds promise of new, more accurate diagnostic tests; more effective therapies; and development of better barriers and eventual vaccines. GTI is, however, and for the foreseeable future will continue to be a major health care problem for women, requiring careful surveillance, management, and ongoing education for both patient and provider.

Female↗
PubMed1995

Age-specific reference ranges for serum prostate-specific antigen.

OBJECTIVES: To assess the relationship of the distribution of serum prostate-specific antigen (PSA) to age in a population of subjects for whom PSA levels were determined as part of a health fair. METHODS: Between March 19 and March 28, 1993, 1716 men aged 40 to 79 years from eastern Nebraska who participated in "The Health Fair of the Midlands" provided blood for serum PSA determination. RESULTS: Serum PSA concentration was correlated with patient age, with the observed 95th percentile increasing from 1.5 ng/mL for subjects 40 to 44 years of age to 7.7 ng/mL for subjects 75 to 79 years of age. Variability in serum PSA concentrations increased with increasing age. Taking this heteroscedasticity into account provided the following upper limits of normal (95th percentiles) for serum PSA: age 40 to 49, 1.5; age 50 to 59, 2.6; age 60 to 69, 4.4; age 70 to 79, 7.5. CONCLUSIONS: Previously published age-specific reference ranges did not consider the increasing variability of PSA concentration with age and have upper limits of normal that are too high for subjects under age 60 and may be too low for subjects aged 70 to 79. Upper reference ranges of 1.5 ng/mL for subjects aged 40 to 49, 2.5 ng/mL for subjects aged 50 to 59, 4.5 ng/mL for subjects aged 60 to 69, and 7.5 ng/mL for subjects aged 70 to 79 years provide specificity near 95%.

Adult↗
PubMed1995

Oral ciprofloxacin as prophylaxis in gastroduodenal surgery.

One hundred and fifty patients undergoing gastroduodenal surgery were randomly allocated to receive intravenous (iv) cefuroxime, iv ciprofloxacin or oral ciprofloxacin as prophylaxis. There were no differences in the incidence of postoperative infection complications or duration of stay among the three groups. Oral ciprofloxacin offers obvious advantages in terms of ease of administration and cost.

Administration, Oral↗
PubMed1995

Effect of memory decay on predictions from changing categories.

In contrast to the static categories assumed in most categorization experiments, many real-world categories undergo gradual and systematic change in their definitions over time. Four experiments were carried out to study such category change. In these studies, participants successfully adjusted as category change occurred, but also showed a lingering and cumulative effect of past observations. The participants' performance was closely modeled by incorporating memory decay for past observations into J. R. Anderson's (1990, 1991) rational categorization algorithm and into a version of R. M. Nosofsky's (1986) exemplar categorization model. The resulting models suggest that the decay function is closer to a power law than to an exponential and that decay occurs both by item and by time, with the item decay being stronger than the time decay. The finding of power law decay gives additional support to claims that exemplar memories are used in categorization.

Humans↗
PubMed1995

Principal component analysis and the scaled subprofile model compared to intersubject averaging and statistical parametric mapping: I. "Functional connectivity" of the human motor system studied with [15O]water PET.

Using [15O]water PET and a previously well studied motor activation task, repetitive finger-to-thumb opposition, we compared the spatial activation patterns produced by (1) global normalization and intersubject averaging of paired-image subtractions, (2) the mean differences of ANCOVA-adjusted voxels in Statistical Parametric Mapping, (3) ANCOVA-adjusted voxels followed by principal component analysis (PCA), (4) ANCOVA-adjustment of mean image volumes (mean over subjects at each time point) followed by F-masking and PCA, and (5) PCA with Scaled Subprofile Model pre- and postprocessing. All data analysis techniques identified large positive focal activations in the contralateral sensorimotor cortex and ipsilateral cerebellar cortex, with varying levels of activation in other parts of the motor system, e.g., supplementary motor area, thalamus, putamen; techniques 1-4 also produced extensive negative areas. The activation signal of interest constitutes a very small fraction of the total nonrandom signal in the original dataset, and the exact choice of data preprocessing steps together with a particular analysis procedure have a significant impact on the identification and relative levels of activated regions. The challenge for the future is to identify those preprocessing algorithms and data analysis models that reproducibly optimize the identification and quantification of higher-order sensorimotor and cognitive responses.

Adult↗
PubMed1995

Generation and characterization of a delta F508 cystic fibrosis mouse model.

We have generated mice carrying the most common mutation in cystic fibrosis (CF), delta F508, within the cystic fibrosis (Cftr) gene. Mutant animals show pathological and electrophysiological changes consistent with a CF phenotype. delta F508-/- mice die from peritonitis and show deficiencies in cAMP-activated electrogenic Cl- transport. These mice produce delta F508 transcripts and show the temperature-dependent trafficking defect first described for the human delta F508 CFTR protein. A functional CFTR Cl- channel not demonstrated by null CF mice or present at 37 degrees C was detected following incubation of epithelial cells at 27 degrees C. Thus, these mice are an accurate delta F508 model and will be valuable for testing drugs aimed at overcoming the delta F508 trafficking defect.

Animals↗
PubMed1995

Comparison of subcutaneous and intravenous administration of recombinant human granulocyte-macrophage colony-stimulating factor for peripheral blood stem cell mobilization.

In an effort to determine whether subcutaneous or continuous intravenous infusion administration of rhGM-CSF results in better hematopoietic progenitor mobilization, the findings of two sequential clinical trials were reviewed. Patients who had received prior chemotherapy for leukemia, lymphoma, multiple myeloma, breast cancer, or other solid tumors and were candidates for high-dose therapy received rhGM-CSF, 250 micrograms/m2/day, either as a continuous intravenous infusion (trial 1) or subcutaneously (trial 2) for stem cell mobilization. At least five apheresis collection procedures were performed to collect a target number of 6.5 x 10(8) mononuclear cells (MNC)/kg. For the 37 patients in trial 1, the collections contained a median of 7.99 x 10(8) MNC/L (range 6.42-21.36) and a median of 5.27 x 10(4) CFU-GM/kg (range 0.28-19.35). In trial 1, 25 patients were autografted with their cells and recovered 0.5 x 10(9) granulocytes/L at a median of 12 days (range 6-16). For the 33 patients in trial 2, the autograft product contained a median of 7.63 x 10(8) MNC/kg (range 6.51-22.66) and 6.31 x 10(4) CFU-GM/kg (range 0.06-60.4). In trial 2, 25 patients were autografted. The median time to reach 0.5 x 10(9) granulocytes/L was 11 days (range 9-26). All patients received rhGM-CSF after peripheral stem cell transplant. No significant differences in the collected products or the time to hematopoietic recovery was found between the two trials (p > 0.05). The mobilization effects of subcutaneous rhGM-CSF in these pretreated patients were similar to those of intravenous rhGM-CSF.

Adult↗
PubMed1995

Tethered flight capabilities and survival of Lambornella clarki-infected, blood-fed, and gravid Aedes sierrensis (Diptera: Culicidae).

Flight capabilities and survival of Lambornella clarki Corliss & Coats-infected, control, blood-fed, and gravid Aedes sierrensis (Ludlow) were monitored using a tethered flight mill system and by recording deaths at various times after initiation of these tests. Flight capabilities of infected and control males as measured by total number of flights, total time spent flying, total distance flown, average flight speed, and percentage time flying were similar. Flight capabilities of females with parasites, with fresh blood meals, and with fully developed eggs did not differ significantly. Flight capabilities of 1- to 2-d-old starved infected and starved control females also did not differ significantly. Although flight capabilities did not differ significantly, infected males died earlier than control males. For females, blooded individuals lived longest, followed by controls, and then gravid and infected individuals. These results and results of glycogen analyses of mosquito thoraces indicate that the parasite primarily affected resources needed by the mosquito for survival and not those for flight.

Aedes↗
PubMed1995

Free flight of Lambornella clarki-infected, blood-fed, and gravid Aedes sierrensis (Diptera: Culicidae).

Total flight times and flight numbers of Lambornella clarki Corliss & Coats-infected and uninfected nonblood-fed (control), blooded, and gravid Aedes sierrensis (Ludlow) were monitored in laboratory experiments using a free-flight acoustical system. Mean flight time and number of males were not affected by L. clarki infection, but mean flight time of infected females was significantly less than those of control and gravid females. Flight numbers of infected and control females did not differ significantly. Blood feeding initially suppressed flight, but flight dramatically increased with increasing time after the blood meal. There was an increase in flight that corresponded to increased parasite presence inside the ovaries in young, but not older, females.

Aedes↗
PubMed1995

The role of high-dose therapy and autologous hematopoietic stem cell transplantation for mantle cell lymphoma.

BACKGROUND: Although mantle cell lymphoma (MCL) is a distinct disease entity with well described clinical and pathological features, little information exists regarding its therapy. This paper will evaluate patients with MCL receiving either induction therapy with an anthracycline or high-dose chemotherapy and autologous hematopoietic stem cell transplantation for relapsed disease. PATIENTS AND METHODS: The cases of 14 previously untreated patients with MCL who received an anthracycline-containing combination chemotherapy regimen on Nebraska Lymphoma Study Group protocols from 3/83 to 2/92 were reviewed. During the same time period, a different set of nine patients with recurrent MCL were referred for high-dose chemoradiotherapy and autologous stem cell rescue as salvage therapy. RESULTS: The five year overall (OS) and failure-free (FFS) survivals from the initiation of chemotherapy for the patients receiving an induction therapy with an anthracycline containing regimen were 23% and 8%, respectively. At the time of this analysis, three of the nine transplant patients remain progression-free 7, 12, and 25 months post-transplant. Two year overall and FFS for all nine patients was 34%. CONCLUSIONS: Longer follow-up of greater patient numbers is required to determine whether high-dose therapy can overcome the chemoresistance and increase the cure rate of MCL. Since most patients with this disease have minimal chance of cure with standard chemotherapy, the optimal timing for high dose therapy may be as part of front-line treatment. Further clinical trials are required to investigate the potential benefits of high-dose therapy for patients with MCL.

Aged↗
PubMed1995

Ischaemic retinopathy occurring in patients receiving bone marrow allografts and campath-1G: a clinicopathological study.

AIMS/BACKGROUND: Ischaemic retinopathy is a well characterised complication of bone marrow transplantation (BMT). Although the aetiology is unclear, it is most probably multifactorial, and may be related to treatment such as radiation and cyclosporin A. The clinical findings are reported of two patients who developed such a retinopathy and the ocular histology from one of these cases is presented. METHODS: Two patients underwent BMT for acute lymphoblastic leukaemia, receiving campath-1G for prophylaxis against graft versus host disease, and showed fundal changes compatible with BMT retinopathy. The eyes from one patient were retrieved at post mortem and examined by both light and electron microscopy. RESULTS: The visual symptoms and fundal signs resolved spontaneously with no specific treatment in one patient. Light and electron microscopic examination of the eyes of the other patient was compatible with an ischaemic aetiology and showed evidence of retinal capillary endothelial loss. CONCLUSIONS: (i) Histopathology in one case of BMT retinopathy demonstrates a retinal endotheliopathy similar to that described in radiation retinopathy. (ii) BMT retinopathy may occur in the absence of cyclosporin A treatment. (iii) The retinopathy can recover spontaneously with no specific treatment.

Adult↗