Leukemia,lymphoma, and multiple myeloma following selected medical conditions

The role of selected prior medical conditions in the etiology of hematopoietic malignancies was examined in a case-control study of members of two regional branches of the Kaiser Permanente Medical Care Program (USA). Past history of chronic infectious, autoimmune, allergic, and musculoskeletal disorders was abstracted from medical records for leukemia (n = 299), non-Hodgkin's lymphoma (NHL, n = 100), and multiple myeloma (n = 175) cases and matched controls (n = 787). Little difference was found between cases and controls for most of the chronic conditions evaluated, including sinusitis, carbuncles, urinary tract infections, pelvic infections, herpes zoster, asthma, rheumatoid arthritis, psoriasis, bursitis, and gout. Only three statistically significant elevated risks were found, i.e., with combined disc disease myeloma among patients with prior eczema and disk and other musculoskeletal conditions, and NHL following tuberculosis. Only two of these associations showed consistent patterns by sex and geographic region (myeloma with eczema and with musculoskeletal conditions). While prior history of eczema and musculoskeletal conditions may slightly increase risk of myeloma, this study provided little if any support for an association of chronic infectious, autoimmune, allergic, and musculoskeletal conditions with subsequent occurrence of the leukemias or NHL. Additionally, these data did not support a role for chronic antigenic stimulation, as defined in previous epidemiologic studies, in the etiology of hematopoietic malignancies.Ms Doody and Drs Linet, Pottern, Boice, and Fraumeni are with the Epidemiology and Biostatistics Program, National Cancer Institute. Dr Glass is with the Kaiser Permanente Medical Care Program, Northwest Region, Portland, Oregon, USA. Dr Friedman is with the Kaiser Permanente Medical Care Program, Northern California Region, Oakland, California, USA. Address correspondence to Ms Doody, Radiation Epidemiology Branch, National Cancer Institute, Executive Plaza North, Room 408, Bethesda, MD 20892, USA. This research was supported in part by National Cancer Institute contracts NO1-CP-01047, NO1-CP-01054, NO1-CP-11009, NO1-CP-11037, NO1-CP-31035, and NO1-CP-61006.     

Staphylococcus aureus nasal carriage in patients with rhinosinusitis

Toxic shock syndrome has been associated with rhinologic surgery and medical devices, and it has been linked to a circulating exotoxin of a toxogenic strain of Staphylococcus aureus. One hundred forty patients with rhinosinusitis were studied. Nasal cultures were obtained. The microbiological characteristics are described. The carrier rate for Staphylococcus aureus was 35%. Thirty percent of patients selected for surgery were Staphylococcus aureus carriers. Toxin-capable isolates were identified in 40% of those tested. Users of cocaine, topical decongestants, and steroid sprays had a statistically higher rate of Staphylococcus aureus carriage compared to non-users. It is hoped that by identifying the population at risk and defining the factors associated with the development of toxic shock syndrome, a cogent policy of prevention can be established.     

Can a Single Muscle Fiber Model the Features of Myocardial Stunning?

The exact mechanisms that cause myocardial stunning are still unclear. We previously utilized a computer model of the ventricle that was effective in modeling the dominant observable features of stunning, but it was not simple to implement. This led to the design of a single muscle fiber model. The mathematical model of a muscle fiber consisted of three elements: a contractile element, a series elastic element, and a parallel elastic element. The model created length waveforms based on time-dependent force and contractile stiffness functions. This model was initially evaluated by entering the same regional parameter values used in the global dual region ventricular model. First a reduction of the contractile stiffness function was applied by reducing the peak stiffness by 30%, and then the rates of activation and deactivation were reduced by 20% while maintaining the peak values constant. The three-element model produced results very similar to the canine and ventricular model. Thus, it is concluded that the simpler three-element model provides an accurate model of the myocardial tissue and its deficiencies during stunning.     

Prophylactic use of chlorpromazine to improve survival of random skin flaps in pigs

On the basis of earlier success in rat studies, chlorpromazine was evaluated as a probable agent for improving survival of random skin flaps in pigs. The aim was to exclude the possibility that the effect of the chlorpromazine is species specific and to find out if it is dose dependent. One hundred and five dorsally-based 12×4 cm flaps were raised unilaterally on the backs of 15 pigs. The animals were divided into three groups using 15 mg/kg chlorpromazine, 7.5 mg/kg chlorpromazine, and a saline-treated control group. Flaps in the control group averaged 40.57±3.17% necrosis, while flaps in the 15 mg/kg and 7.5 mg/kg chlorpromazine-treated groups averaged 31.53±4.77% and 11.47±2.22% necrosis respectively. These results demonstrate dose dependent beneficial affects of chlorpromazine and the survival of random skin flaps in the pig. Although ideal dose levels are still to be determined, flap survival improved with the prophylactic use of chlorpromazine at the lower 7.5 mg/kg dosage.     

Distribution of normal and abnormal fluid collections in the glenohumeral joint: Implications for MR arthrography

Although magnetic resonance (MR) images of the glenohumeral joint frequently demonstrate intraarticular fluid, no specific criteria have, to the authors' knowledge, been published that allow accurate assessment of the amount of fluid present. Also, despite the increasing use of MR arthrography of the shoulder, the optimal amount of intra-articular fluid that should be used with this technique has not been determined. The authors progressively distended the glenohumeral joint in six cadaveric shoulder specimens with a dilute gadopentetate dimeglumine solution and obtained MR images after injection of 2, 5, 10, 15, and 20 mL of the solution. The pattern of fluid distribution was evaluated, and these results were then used to estimate the amount of fluid that was present in the glenohumeral joint on MR images of 20 shoulders obtained in 12 asymptomatic volunteers. In 14 of these shoulders, intraarticular fluid was present; however, in none was more than 2 mL evident. Results of the cadaveric study also indicated that 15 mL of intraarticular fluid appears to be the optimal amount for MR arthrography.     

Ninety-Six Five-Year Survivors After Liver Resection for Metastatic Colorectal Cancer

Background: Studies have consistently confirmed the benefit of liver resection for metastatic colorectal cancer. Few reports, however, have a long enough followup or sufficient 5-year survivors to study the clinical course of patients beyond 5 years.

Study Design: From July 1985 through December 1991, 456 patients underwent liver resection for colorectal metastases. Ninety-six actual 5-year survivors (21%) were identified and their clinical course retrospectively reviewed.

Results: Five-year survivors (n = 96) were more likely to have a Duke’s B primary colorectal carcinoma, fewer than four metastatic lesions, unilobar disease, and a negative histologic margin when compared with patients not surviving 5 years (n = 298). Forty-four (46%) of the 96 five-year survivors had a recurrence after hepatectomy. Of these 44, 19 (43%) were rendered disease free after further treatment. Overall, 71 of the 96 five-year survivors were free of disease at last followup. The actuarial 10-year survival of this group was 78%.

Conclusions: Patients that are disease free 5 years after liver resection are likely to have been cured by liver resection. Patients should be aggressively followed for recurrence because of the potential for further treatment and longterm survival.     

Localized echo-volume imaging methods for functional MRI

To perform true three-dimensional activation experiments in the human brain, dedicated localized echo-volume imaging (L-EVI) methods were developed. Three-dimensional acquisition allows generation of activation maps with minimal vascular enhancement related to inflow effects. The rapid acquisition of the L-EVI (～100 msec) reduces signal instabilities caused by motion, facilitating the detection of the small intensity changes expected with brain activation. Single-shot L-EVI was performed on normal volunteers at 1.5 T, imaging a three-dimensional predefined volume (240 × 45 × 45 mm³) in the superior portion of the brain with a spatial resolution of 3.75 × 5 × 5 mm³. Increased brain coverage was achieved with a multi-volume imaging (three-shot) version, which simultaneously achieved effective suppression of signals from cerebrospinal fluid. In addition, both asymmetric spin-echo (ASE) and spin-echo (SE) versions of the technique were used to detect blood oxygenation level dependent (BOLD) signal changes in the motor cortex with a finger-tapping paradigm. Images obtained by the L-EVI sequence were qualitatively comparable to standard multislice two-dimensional echo-planar images. Both ASE and SE functional MRI (fMRI) experiments showed consistent activation in the contralateral primary sensorimotor cortex. Furthermore, significant differences in location and magnitude of activation was observed between the two methods, confirming theoretical predictions.     

Cholecystokinin and neuropeptide Y receptors on single rabbit vagal afferent ganglion neurons: site of prejunctional modulation of visceral sensory neurons

A [¹²⁵I]cholecystokinin (CCK) analog and [¹²⁵I]peptide YY (PYY) were used to localize and characterize CCK and neuropeptide Y (NPY) receptor binding sites in the rabbit vagal afferent (nodose) ganglion. High concentrations of CCK and NPY binding sites were observed in 10.6% and 9.2% of the nodose ganglion neurons, respectively. Pharmacological experiments using CCK or NPY analogs suggest that both subtypes of CCK (CCK-A and CCK-B) and NPY (Y1 and Y2) receptor binding sites are expressed by discrete populations of neurons in the nodose ganglion. These results suggest sites at which CCK or NPY, released in either the nucleus of the solitary tract or a peripheral tissue, may modulate the release of neurotransmitters from a select population of visceral primary afferent neurons. Possible functions mediated by these receptors include modulation of satiety, opiate analgesia, and the development of morphine tolerance.