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T Smith

Publications and source records attributed to T Smith.

At least 667 records · Page 37Linked to original sources
PubMed1987

Nonsteroidal antiinflammatory drug-induced intestinal inflammation in humans.

This study examines the effects of nonsteroidal antiinflammatory drugs on the small intestine in humans. Using an 111In-leukocyte technique in patients with rheumatoid arthritis (n = 90) and osteoarthritis (n = 7), it appears that nonsteroidal antiinflammatory drugs cause small intestinal inflammation in two-thirds of patients on long-term treatment and on discontinuation, the inflammation may persist for up to 16 mo. The prevalence and magnitude of the intestinal inflammation was unrelated to the type and dose of nonsteroidal drugs and previous or concomitant second-line drug treatment. There was a significant inverse correlation (r = -0.29, p less than 0.05) between fecal 111In excretion and hemoglobin levels in patients treated with nonsteroidal antiinflammatory drugs. The kinetics of fecal indium 111 excretion in patients treated with nonsteroidal antiinflammatory drugs was almost identical to that of patients with small bowel Crohn's disease. Eighteen patients on nonsteroidal antiinflammatory drugs underwent a radiologic examination of the small bowel and 3 were found to have asymptomatic ileal disease with ulceration and strictures. Nineteen patients on nonsteroidal antiinflammatory drugs, 20 healthy controls, and 13 patients with Crohn's ileitis underwent a dual radioisotopic ileal function test with tauro 23 (75Se) selena-25-homocholic acid and cobalt 58-labeled cyanocobalamine. On day 4, more than half of the patients with rheumatoid arthritis had evidence of bile acid malabsorption, but the ileal dysfunction was much milder than seen in patients with Crohn's ileitis.

Adolescent↗
PubMed1987

Motor unit firing intervals and other parameters of electrical activity in normal and pathological muscle.

The analysis of the firing intervals of motor units has been suggested as a diagnostic tool in patients with neuromuscular disorders. Part of the increase in number of turns seen in patients with myopathy could be secondary to the decrease in motor unit firing intervals at threshold force of the motor units, as noted in previous studies. In the brachial biceps muscle we have studied the firing intervals of 164 motor units in 14 controls, 140 motor units in 13 patients with myopathy and 86 motor units in 8 patients with neurogenic disorders, and related the findings to those of the turns analysis and the analysis of properties of individual motor unit potentials. To ensure comparable conditions we have examined motor unit firing intervals and turns at a force of 10% of maximum. The average of motor unit firing intervals and of interval variability was the same in controls and in patients, and the diagnostic yield of the motor unit firing intervals analysis was none. Although the number of turns increased with decreasing motor unit firing intervals, this relation was physiological rather than pathophysiological. In patients with neurogenic disorders, interval variability indicated unstable firing in severely affected muscles.

Action Potentials↗
PubMed1987

Toward a clinically relevant cytogenetic classification of acute myelogenous leukemia.

Cytogenetic studies with Giemsa banding were performed on the bone marrow cells of 384 patients with acute myelogenous leukemia treated between 1975 and 1983. An abnormal karyotype was detected in 54% of patients, being present in 100% of metaphases (AA) in 31% and only a proportion of cells (AN) in 22%. Specific translocations or other abnormalities were noted in 22% of patients, the most common of which were t(8;21) (q22;q22) in 7%, t(15;17) (q22;q21) and inv (16) (p13q22) in 5.5%, t(9;22) (q34;q11) in 3% and abnormalities of 11q23 in 1.3%. Loss of the Y chromosome was noted in 21 patients, associated with t(8;21) in 11 patients and the sole abnormality in eight patients (45, X, -Y). Most (66%) of the other abnormalities involved addition of chromosome 8 or loss or deletion of 5 or 7 (+8, -5 or -7, 5q- or 7q- group). The remaining patients had miscellaneous abnormalities (MA). A marked assymetry was noted in the distribution of important clinical prognostic variables such as age, sex, history of an antecedent hematologic disorder and presence of Auer rods within the various cytogenetic categories. The specific translocation/abnormalities were more common in younger patients (p less than 0.01). Analysis of response, remission duration and survival demonstrated that inv 16 and t(8;21) were favorable prognostic categories; diploid, t(15;17) and 45,X,-Y had intermediate prognosis, and all other categories were unfavorable prognostic groups. The response rate and survival for diploid patients (NN) was superior to patients with abnormalities. No difference in response rate, CR duration or survival was noted between the AA and AN groups. A prognostic classification according to cytogenetic category based on clinical associations is proposed which will be tested prospectively in subsequent studies.

Adult↗
PubMed1987

The effect of elastase on chickens with endogenous hyperlipidemia.

Elastase has been reported to have a multiplicity of activities which may be protective against atherosclerosis. The data reported here support those reports and show a clear antiatherosclerotic effect in hyperlipidemic chickens. We have shown here that a reduction in calcium and lipid accumulation in aortic tissue and possibly a plasma cholesterol lowering effect can be seen in the chicken when treated with elastase. The most important effect in this animal is probably to aid removal of lipid bound to elastin in the intima. This was achieved at a dose of only 600 U elastase while reductions in tissue calcium required 1800 U elastase.

Administration, Oral↗
PubMed1987

Knowledge about hand shaping and knowledge about objects.

Our two experiments investigated associations between cognitive representations of objects and hand-shape categories. Hand configurations were partitioned according to prehensility and the size of the contacting surface, resulting in the classes: pinch, poke, palm, and clench. Experiment 1 elicited object names in response to configuration-name cues, provided ratings of the relevance of each configuration to a set of objects, and probed for the functions determining such relevance. Cueing with a configuration class elicited an associated object category with substantial intersubject agreement, and vice versa. Both the object categories and the functions associated with the four hand-configuration classes differed substantially, although the same object could be associated to some extent with multiple configurations, given variations in function. Experiment 2 elicited the names of hand-configuration classes in response to unfamiliar forms, which varied systematically in depth and the size of the projecting picture-plane surface. The modal response, response time, and degree of intersubject agreement were directly related to these variables. These structural variables, however, did not adequately predict shaping responses to real objects, as ascertained from Experiment 1. The results have implications for cognitive representation of motor categories and hand shaping in response to objects.

Journal Article↗
PubMed1987

Critical analysis of the accuracy of a combined test (75Se-HCAT and 58Co-B12) of ileal function using a whole-body counter.

The accuracy of a combined test (75Se-HCAT + 58Co-B12) of ileal function by whole-body counting has been assessed with particular attention being paid to the reliability of the 100% retention measurements, the accuracy of the crossover of 58Co into the 75Se channel and the effects of variable counting geometry. A linear relationship between 58Co crossover and body weight improved the accuracy of determining the crossover value for individual patients. Non-geometrical errors such as those associated with counting statistics and crossover were found to be small, with a coefficient of variation usually less than +/- 2% except in cases of very low 75Se-HCAT retention in the presence of substantial amounts of 58Co. The main sources of error were due to problems of variable counting geometry but there was very good agreement between 75Se and 58Co retentions measured by whole body counting and by excreta analysis which suggested that the overall error of the test was unlikely to exceed +/- 10%. A protocol is presented for use of the combined test on an outpatient basis and includes retention measurements at 4, 7, and 10 d post administration.

Cobalt Radioisotopes↗
PubMed1987

Ileal leiomyosarcoma and leiomyoma. False-positive scintiscans for Meckel's diverticulum.

Two cases of ileal leiomyomatous neoplasms with positive scintigraphic findings for Meckel's diverticulum are presented. The precise mechanism for the abnormal concentration of the Tc-99m pertechnetate is uncertain. Illustrations of the collating barium and computerized tomographic studies are included and the scanning technique utilized is reviewed.

Diagnosis, Differential↗
PubMed1987

Measurement of exchangeable sodium: 22Na or 24Na?

A case is made for the use of 22Na in low activities in preference to 24Na for routine diagnostic estimation of exchangeable sodium, and is based chiefly on considerations of availability, cost and radiation dosimetry. A method in which only 37 kBq (1 microCi) 22Na is administered orally is shown to be sufficiently accurate and to possess distinct advantages in terms of cost and convenience with a committed radiation dose no greater than that for a measurement using 24Na.

Body Composition↗
PubMed1987

Peripheral neuropathy associated with plasma cell dyscrasia: a clinical and electrophysiological follow-up study.

Thirteen patients with polyneuropathy associated with plasma cell dyscrasia had serial electrophysiological studies. Five patients with monoclonal IgG had motor and/or sensory symptoms of which 4 correlated with slow motor and sensory nerve conduction. The 4 patients with monoclonal IgM reactive with myelin-associated glycoprotein (MAG), had predominantly motor symptoms, demyelination in the nerve biopsy and slow motor and sensory nerve conduction. Four patients with monoclonal IgM without anti-MAG activity had mainly sensory symptoms, axonal neuropathy on nerve pathology and slow or absent sensory nerve conduction. After treatment with plasmapheresis and chemotherapy 9 patients improved clinically and 4 were unchanged. Criteria for electrophysiologic improvement were presence of sensory or motor responses that were absent before treatment, conduction velocity increased by more than 10 m/s and increase of amplitude by more than 100%. Electrophysiological studies showed improvement in 7, were unchanged in 4, and worse in 2. Sensory velocities in ulnar and sural nerves were significantly improved following treatment (P less than 0.002) and the same trend was noted for the sensory velocity in the median nerve (P less than 0.19). We conclude that nerve conduction studies in combination with clinical examinations are useful in documenting the effects of treatment in these neuropathies.

Action Potentials↗
PubMed1987

Survival after balloon atrial septostomy for complete transposition of great arteries.

Mortality before surgery must be taken into account when comparing the surgical mortality of atrial redirection procedures (Mustard's or Senning's operation) and the arterial switch operation for patients with complete transposition. This is because the switch operation is usually performed within the neonatal period or early infancy but Mustard's or Senning's operation usually after 4 months of age. The outcome of balloon atrial septostomy was therefore assessed in all 102 infants with transposition of the great arteries (plus or minus associated anomalies) who underwent the procedure at our hospital in the 10 years from January 1975 to December 1984. We considered the procedure to have been unsuccessful if the patient died from any cause (including other surgical procedures) between the septostomy and subsequent interatrial repair (Mustard's operation) or arterial switch operation. Eighteen patients died, although in only two was this as a direct result of the septostomy. Statistical analysis showed that low weight, presence of a persistent arterial duct, and coarctation of the aorta were significant risk factors. Early survival of infants with transposition of the great arteries has been dramatically improved after the introduction of balloon atrial septostomy. Nevertheless, there is considerable attrition before definitive repair, which must be included in the prediction of overall outcome.

Body Weight↗
PubMed1987

Comparison of results of salvage therapy in adult acute myelogenous leukemia.

The results of initial salvage therapy for refractory and relapsed acute myelogenous leukemia for patients treated between 1973 and 1986 have been evaluated. There was no significant improvement in complete remission (CR) rate and survival in patients treated between 1973 and 1980, and the second group between 1981 and 1986. The remission duration was slightly longer in the second time period than in the initial time period. A number of factors were associated with the probability of achieving a CR. The major factors were the age of the patient, duration of the initial CR, liver function test abnormalities, and white blood cell count.

Adult↗
PubMed1987

Magnetic resonance imaging in pediatric neurologic disorders.

We present our initial experience with magnetic resonance imaging (MRI) in 301 pediatric patients with a variety of neurologic disorders. MRI does not require ionizing radiation and can be done easily and safely in children. It is equal or superior to computed cranial tomographic (CT) scans in demonstrating most types of pediatric neurologic disorders. MRI is often superior to CT scans in demonstrating intracranial tumors, although both studies are usually abnormal in highly malignant tumors. No clear advantage was shown with either MRI or CT scans for fluid-filled intracranial lesions. Lesions of the brain stem and upper cervical region, such as Chiari malformation, are well delineated by MRI. Increased signal from the paranasal sinuses was frequently evident by MRI, but, in most instances, there was no clinical indication of sinus disease. Large arteries can be visualized as an area of diminished signal, and intracranial hemorrhage, dural sinus thrombosis, and cerebral infarction were demonstrated. The increased anatomic detail pictured by MRI allows the diagnosis of congenital defects, such as agenesis of the corpus callosum or septum pellucidum, that are not always apparent with CT scans. Although our experience with spinal cord lesions was not extensive, fluid-filled lesions within the cord can be reliably demonstrated.

Adolescent↗
PubMed1987

Results of MIME salvage regimen for recurrent or refractory lymphoma.

Based on encouraging results of two previous ifosfamide-VP-16 salvage combinations, methyl-gag was added to ifosfamide, methotrexate, and etoposide (VP-16). This combination is called MIME. A total of 208 patients with recurrent lymphoma were treated with this regimen. Response rates were 24% for complete remission and 36% for partial remission. The MIME regimen was more effective in patients who were treated after being off front-line therapy for longer than 6 months. However, responses were also seen in patients with disease clearly resistant to front-line therapy, suggesting that MIME was at least partially non-cross-resistant with front-line doxorubicin-containing regimens. The 15-month median relapse-free survival of complete responders and the 9-month overall median survival time for all patients treated were both similar to results from previous ifosfamide-VP-16 combination use. This regimen has been effective in the treatment of patients with recurrent or refractory lymphoma, but cannot be considered curative in the majority of cases.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1987

The pathogenesis and consequence of non steroidal anti-inflammatory drug induced small intestinal inflammation in man.

Non steroidal anti-inflammatory drugs (NSAID's) have recently been shown to cause small intestinal inflammation in the majority of patients receiving these on a regular basis for more than one year. The development of inflammation is preceded by an NSAID effect to increase small intestinal permeability. Increased intestinal permeability is shown to be related to drug potency to inhibit cyclooxygenase and the effect is systemically mediated rather than a local irritant one. More recently, increased intestinal permeability due to NSAID's has been reduced by concomitant prostaglandin administration, showing that prostaglandins are essential for maintaining intestinal integrity in man. It is proposed that altered intestinal permeability allows the mucosa to be exposed to bacterial degradation products or other toxins and together with reduced chemotaxic response and altered neutrophil function due to NSAID's, this series of events leads to bacterial invasion of the mucosa which is evident by the techniques of 111Indium leucocyte scans and faecal collections. The consequence of such inflammation is that it may explain intestinal perforations and strictures which are occasionally seen in subjects on NSAID's. Most patients with NSAID-induced small intestinal inflammation may be bleeding from the intestine, loosing protein and some have ileal dysfunction. The small intestine may be a greater source of morbidity than the stomach, in patients receiving NSAID's.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1987

Radiation absorbed dose from technetium-99m DTPA.

The whole-body retention of intravenously administered [99mTc]DTPA was measured by urine analysis and whole-body counting in eight normal subjects. On average, the elimination of [99mTc]DTPA was faster in these subjects than in 11 patients under study for hypertension whose whole-body retention data were used in MIRD Dose Estimate Report No. 12. The average residence time for [99mTc]DTPA in total body, less bladder contents, was only 65% of the MIRD value. However, despite this difference, the dosimetry is similar in both cases largely owing to the influence of radioactivity in bladder contents. Approximately 2-3% of the administered radioactivity was retained in the body for a time that was long relative to the physical half-life of 99mTc, and probably reflects a small amount of protein binding of the DTPA preparation.

Adult↗
PubMed1987

Regression of melanoma nodules in a patient treated with ranitidine.

Human malignant melanoma may regress spontaneously or with immunotherapy, such as Calmette-Guerin bacillus, interferon alfa, interleukin-2, and interleukin-2 plus lymphokine-activated killer cells. Histamine type 2 receptor antagonists can modulate immune function by inhibiting suppressor T-cell induction and activity, and melanoma regressions have been reported after the use of cimetidine with coumarin or interferon alfa. This article describes the complete regression of melanoma nodules in a patient treated with ranitidine hydrochloride, another histamine type 2-receptor antagonist. Ranitidine and cimetidine should be considered to be possibly active immunotherapeutic agents in the design and evaluation of clinical trials.

Female↗
PubMed1986

Fatty replacement of lymph nodes mimicking lymphoma relapse.

A 70-year-old man was treated successfully for diffuse histiocytic lymphoma involving the left ilium and bone marrow. He received radiation therapy to the left hip for stabilization, then eight cycles of intense (COP-BLAM) chemotherapy. Restaging at the completion of therapy demonstrated a normal physical examination, laboratory values, bone scan, bone survey, and abdominal computerized tomographic scan. One month after restaging he developed rapidly enlarging lymphadenopathy. Biopsy of an axillary node showed complete fatty replacement without lymphoma, and the patient remains in remission 16 months later. Recent reports of residual masses after lymphoma therapy have demonstrated fibrous replacement, necrotic tissue, thymic hyperplasia, and vascular anomalies mimicking lymphadenopathy. Lymph node enlargement may be due to nonmalignant causes, including fatty replacement, and not due to recurrent lymphoma.

Adipose Tissue↗