Chemiluminescence by polymorphonuclear leukocytes from patients with active bacterial infection

Polymorphonuclear leukocytes of 18 patients during 19 episodes of active bacterial infection produced increased chemiluminescence (mean +/- standard error [SE], 56.3 +/- 4.4 X 10(3) cpm) when the production was compared to that of 29 uninfected controls (35.3 +/- 2.4 X 10(3) cpm; P less than 0.01). Chemiluminescence production remained increased with persistent infection but fell to the levels of controls with appropriate therapy. Phagocytic uptake as determined with radiolabeled bacteria was increased, and chemotactic responsiveness was markedly enhanced in the patients (mean index +/- SE, 260 +/- 51) when these responses were compared with those of controls (77 +/- 18). Chemiluminescence and chemotactic activity correlated in the patients with bacterial infection (r = 0.76), but one function did not appear to depend upon the intactness of the other. The ratio of cyclic guanosine 3',5'-phosphate to cyclic adenosine 3',5'-hosphate in the polymorphonuclear leukocytes of patients with infections (mean +/- SE, 0.102 +/- 0.0008) was also significantly higher than in controls (0.067 +/- 0.007). These data indicate that the polymorphonuclear leukocytes of the majority of patients with active bacterial infection are in an activated state both functionally and metabolically.     

Dynamic computed tomography. Its use in the assessment of vascular malformations and angiofibroma

Reliable diagnostic methods for head and neck vascular lesions are needed. The technique of dynamic computed tomography (CT) is used to delineate two aberrant subclavian arteries, one carotid artery aneurysm, and one angiofibroma. Five or six 4.8-s CT scans were obtained sequentially, separated by a 1.2-s interscan interval. Computer-generated iodinated contrast concentration (CT number) v time curves showed rapid influx of contrast, high peak density, and rapid uninterrupted contrast runoff. Simultaneous bone and soft-tissue visualization at the time of peak contrast enhancement provides excellent delineation of the malformations and angiofibroma. The technique is noninvasive, and it eliminates the potential complications of arteriography and biopsy. We conclude that dynamic CT is an excellent method for diagnosis of head and neck vascular lesions.     

Power deposition patterns in magnetically-induced hyperthermia: a two-dimensional low-frequency numerical analysis

The electric fields and power deposition patterns generated in two-dimensional inhomogenous models exposed to the axially directed uniform magnetic fields of an infinitely long solenoid are calculated numerically. The fields are calculated using the method of moments (Galerkin procedure) with linear basis and weighting functions. This low-frequency analysis is useful for studying the power deposition patterns attributable to solenoidal inductive applicators operated at frequencies up to 13.56 MHz. For the models we have studied, the ratio of power per volume deposited into the tumor to power per volume deposited into the immediately surrounding tissue is largest for tumors in the lung, although the power per volume deposited into the outermost layer is still much larger than the power per volume deposited into the tumor; it may be possible, however, to cool this region adequately from the body surface. When the complex permittivity of the tumor model is similar to that of the region in which it is embedded, the currents in the torso and tumor circulate primarily around the center of the body, as has been previously calculated for concentric cylinders. When the complex permittivity of the tumor is much greater than the region in which it is embedded, the currents in the tumor circulate primarily around the center of the tumor.     

Response of mouse lung to irradiation at different dose-rates

Groups of LAF1 mice were given thoracic irradiation using 60Co gamma-rays at dose-rates of 0.05 Gy/min (LDR) or 1.1 Gy/min (HDR) and the death of the animals was monitored as a function of time. It was found that the time pattern of animal deaths was similar for the two different dose-rates. Dose response curves for animals dying at various times up to 500 days after irradiation were calculated and the LD50 values determined. The curves for the LD50 values, plotted as a function of the time at analysis for treatment at HDR or LDR, were essentially parallel to each other but separated by a factor (LDR/HDR) of about 1.8. This indicates that the sparing effect of LDR treatment is the same for deaths occurring during the early pneumonitis phase or during the late fibrotic phase of lung damage. The available information on the response of patients to whole thoracic irradiation, given for either palliation or prior to bone marrow transplantation, suggests that for similar dose-rates to those studied here the ratio (LDR/HDR) is only 1.2-1.3. This difference between the animal and human data may reflect the modifying effect of the large doses of cytotoxic drugs used in combination with the irradiation of bone marrow transplant patients.     

Renal transplantation in a patient with multiple myeloma and light chain nephropathy

A case of multiple myeloma in a 41-year-old white man that resulted in chronic renal failure is discussed. During the period of hemodialysis treatment, remission of the patient's myeloma was induced by chemotherapy. Thereafter a transplanted cadaver kidney functioned well for 3.5 years despite episodes of sepsis, administration of nephrotoxic chemotherapeutic agents, and recurrence of the myeloma with intermittent excretion of Bence Jones protein in the urine. The results of this fully documented case, as well as two other cases we have previously reported, support the strategy of offering cadaver renal transplantation to carefully selected individuals who require long-term dialysis and whose myeloma is in remission after chemotherapy.     

Concentration and time-dependent inter-relationships for antitumour drug cytotoxicities against tumour cells in vitro

Cryopreserved tumour cells obtained from the ascitic fluid of a patient with an ovarian carcinoma were employed to determine the effect on in vitro drug cytotoxicities of varying both drug concentration and exposure time. Four antitumour drugs, in common clinical usage, were selected for study. Tumour-cell survival following drug treatment was measured by colony-forming ability in the soft-agar developed by Courtenay et al. (1978). Treatment with cis-platinum, adriamycin or vinblastine generated exponential survival curves with increasing cell kill resulting from either increasing drug concentrations or prolonging exposure times. In contrast, no detectable cell kill was elicited by treatment with hydroxyurea for short exposure times of 1 or 6 h, even at concentrations as high as 1 mg/ml, although continuous drug exposure resulted in a steep exponential survival curve. These results, obtained directly from biopsy material, are in close agreement with data from parallel studies employing a continuous human tumour-cell line (COLO 205 derived from a colon carcinoma). Duration of exposure is therefore an important determinant of drug-induced cytotoxicity under these assay conditions. The results with hydroxyurea, however, imply that prolonged incubation times are necessary to evaluate the cytotoxicity of certain agents and so the routinely employed 1 h exposure in most current human tumour drug sensitivity tests is inadequate for such drugs. These data therefore provide evidence that employing a single set of standard conditions of drug exposure to evaluate all antitumour drugs may be inappropriate.     

A comparison of two methods for the computer analysis of arterial blood pressure waveforms

Two different methods, one analogue and one digital, for the analysis of the arterial blood pressure waveform are described and compared. Little difference was found in the systolic and diastolic pressures determined by the two methods.     

Fragile X syndrome: associated neurological abnormalities and developmental disabilities

The fragile X syndrome is a frequent cause of developmental disabilities. It is associated primarily with nonprogressive X-linked mental retardation. The neurodevelopmental abnormalities of 25 males and 3 females are described. Mental retardation was mild in 4, moderate in 11, severe in 6, and profound in 2 patients, while 4 patients had only learning disabilities. The presence or absence of a developmental disability could not be determined in the youngest (8 months). Seven patients had had infantile autism and 7 had epilepsy. Generally no major focal neurological abnormalities were observed but most of the patients exhibited minor signs. The severity of developmental disabilities in our patients varied between and within families and between genders. All adult males had macroorchidism. Unusual facial features were present in 13 males but none were seen in the females. Familial occurrences were found in 18 cases (64%); 10 cases (36%) were sporadic. Overall, males were more severely affected than females. Diagnostic tests including computed tomographic scans, electroencephalograms, and evoked potentials did not disclose any specific abnormalities.