Biotransformation by plant cells immobilized in cross-linked polyacrylamide-hydrazide

Plant cells were entrapped by mixing suspended MENTHA cells with linear, water soluble polyacrylamide-hydrazide chains followed by the stoichiometric addition of glyoxal as the cross linking agent (PAAH-G entrapment). In parallel, some cells were entrapped in calcium-alginate beads, as previously described. The capability of both immobilized cell systems to reduce monoterpenes was compared with freely suspended MENTHA cells. Entrapment by either alginate or PAAH-G did not impair cell vitality, as observed by fluorescein diacetate staining. Biotransformation of (-) menthone to (+) neomenthol by M-cells and of (+) pulegone to (+) isomenthone by P-cells indicated that the transformation efficiency of the cells entrapped in PAAH-G is as high as that of freely suspended cells. Moreover, the distribution of both precursor and product in the medium versus their content in the cells (or cells contained in gel-beads) showed that less monoterpenes were retained in cells entrapped in PAAH-G, as compared to the freely suspended cells. Thus prolonged incubation (e.g. 24 hr), which usually results in appreciable loss of monoterpenes from the chloroform extract of freely-suspended-cells, caused considerably less loss from the PAAH-G entrapped-cells. In a preliminary test it was shown that PAAH-G entrapped cells were capable to perform three, consecutive, batch-type monoterpene biotransformations, without significant decrease of transformation capability. The capability to immobilize living plant cells within this synthetic chemically crosslinked gel system, combined with the favourable beads/ free-medium ratio of monoterpene distribution, point towards a potential development of a continuous biotransformation process carried out by plant-cells entrapped in this system.

Leukocyte function in the etiology of acute necrotizing ulcerative gingivitis

Patients with the diagnosis of acute necrotizing ulcerative gingivitis (ANUG) and their controls, matched for age, sex, race and general plaque accumulation, donated blood for differential white blood cell counts and for assay of several leukocyte functions. The leukocyte function assays included polymorphonuclear leukocyte (PMN) responsiveness to chemotaxis and phagocytosis, and lymphocyte responsiveness to stimulation by nonspecific mitogens. The differential leukocyte counts were within the normal range for all subjects tested, and there was no difference between ANUG patients and controls. The ANUG patients did, however, display significantly depressed PMN responsiveness in both chemotaxis and phagocytosis, compared to the controls. There was also reduced DNA synthesis by ANUG patients' lymphocytes upon stimulation by a nonspecific mitogen (Con A). The data presented in this report suggest that depression of some host defense mechanisms, particularly PMN chemotaxis and phagocytosis, may be important in the pathogenesis of ANUG.

High-dose cytoreductive therapy with autologous bone marrow transplantation in advanced malignancies

Twenty-one patients with advanced malignancies received high-dose chemotherapy and/or radiotherapy followed by autologous bone marrow infusion. Eighteen patients (85.7%) had fever greater than or equal to 100 degrees F for a median of 6 days; 14 of these patients required broad-spectrum antibiotics for a median of 13 days. Nineteen patients (90.5%) had a granulocyte count less than 500/mm3 for a median of 11 days. Thrombocytopenia (platelet count less than 50,000/mm3) was observed in 18 patients (85.7%) for a median of 14 days. Mucositis and diarrhea were not common, occurring in six (28.6%) and seven (33.3%) patients, respectively. Of the 21 patients studied, 16 were evaluable for tumor response; there were four complete responses and four partial responses, and two patients who showed no change for variable times. Two patients have unmaintained remissions for greater than 2 years. Our response rate (complete plus partial) is 50%. Our study shows that high-dose cytoreductive therapy can be given with moderate toxicity when combined with autologous bone marrow infusion. Because responses in this group of patients are generally of short duration, we believe that patients with advanced malignancies who have had less exposure to therapy or who have a high likelihood of disease recurrence should be considered for high-dose cytoreductive therapy with autologous transplantation.

Mammalian cell propagation on derivatized polyacrylamide microcarriers

A working system for studying the effects of factors involved in the chemical nature of microcarrier on cell attachment, spreading and growth, was established. The system is based on polyacrylamide beads, prepared by the emulsion polymerization technique. Sieved beads of desirable mean diameter were derivatized to generate controlled amounts of primary and tertiary amino groups. These microcarriers were used for propagation of vive different cell strains: BHK, MDCK, CEF, MRC-5 and FS. It was found that BHK cells attach and spread significantly faster on primary amino derivatized beads than those with tertiary amino groups, and at a lower degree of charging. As a result of introducing hydrophobicity to the side chain carrying the primary amino group, higher kinetic rates of BHK cell attachment were obtained. Optimal cell growth of all the tested cells was recorded for the butyl and the hexyl side chains. On the other hand the introduction of hydrophobicity into the polymeric backbone of the microcarrier led to lower cell yields. Primary amino derivatized MCs with an optimal degree of hydrophobicity city exhibit a higher cell yield of MDCK cells (with pronounced epithelial morphology), as compared to the tertiary amino derivatized MCs. CEF and FS cells (with pronounced fibroblast morphology) attained cell yields comparable to those obtained with the tertiary amino derivatized MCs. The diaminohexane derivatized polyacrylamide microcarriers seem to be a potential alternative for the commonly used tertiary amino derivatized micro-carriers.

The treatment of acute myelocytic leukemia in patients 30 years of age and younger

The treatment of acute myelocytic leukemia in childhood and young adults has lagged behind that for acute lymphocytic leukemia. The studies described here were directed towards evaluating the role of intensive chemotherapy in the treatment of this illness. Intensive remission induction therapy combining cytosine arabinoside with an anthracycline antibiotic produced a complete remission rate comparable to that achieved in acute lymphocytic leukemia (45 of 49 patients or 92%). Intensive consolidation chemotherapy produced a median duration of complete remission of 160 weeks with 40% of patients projected to be in remission at 4 years. By contrast, the median duration of remission for patients treated with moderate consolidation/maintenance therapy was 23 weeks with only 10% of patients in remission at 4 years. These studies demonstrate that intensive chemotherapy can be administered to pediatric patients and young adults and that this approach to therapy produces a high remission rate with a 3 year median duration of remission.

Intrathecal interferon in multiple sclerosis

Human fibroblast interferon (IFN-beta) was administered by serial lumbar puncture to ten patients with multiple sclerosis (MS). Their clinical courses were compared with those of ten MS control patients who did not receive IFN-beta. As of this writing, the recipients have been followed up for 1.8 to 2.0 years (mean, 1.9 years), and the controls for 1.5 to 1.7 years (mean, 1.6 years). During the study, two recipients suffered four exacerbations, and six controls suffered 11 exacerbations. The recipients' rates of exacerbation during the study were significantly less than their rates both for the entire prestudy duration of the disease and for the 1.8 to 2.0 years immediately preceding entry into the study. The controls' rates of exacerbation before the study and during the study period did not differ significantly. Clinically, the conditions of five recipients and two controls improved, those of three recipients and four controls were unchanged, and those of two recipients and four controls worsened. Headaches, sometimes accompanied by fever and rarely by nausea and vomiting, occurred after injections of IFN-beta. Toxic symptoms usually disappeared within 24, hours; rarely, they persisted for seven to ten days. Each recipient had transient CSF pleocytosis and elevated levels to total protein (the latter remaining elevated in seven). These findings show that intrathecal administration of IFN-beta is feasible in patients with MS, warrant cautious optimism that intrathecal IFN-beta may be effective in altering the course of the disease, and support concepts of a viral or dysimmune cause of MS.

Radionuclide ejection fraction: comparison of response to treadmill and bicycle exercise

Most exercise radionuclide studies utilise the supine bicycle ergometer during imaging, although exercise on a treadmill results in greater cardiovascular stress. Twenty-three patients were studied to compare the radionuclide left ventricular ejection fraction (LVEF) estimated immediately following treadmill exercise with that obtained at peak supine bicycle exercise in patients with coronary artery disease (CAD) and patients with normal coronary arteries. In 14 patients with CAD the rest LVEF was 47 +/- 7% (mean +/- SD) by first pass and 49 +/- 10% by equilibrium blood pool techniques. Immediately following maximum treadmill exercise, 13 of the 14 patients with coronary artery disease showed either no change or a decrease in LVEF, the LVEF was 49 +/- 7% (P = NS) and 47 +/- 8% (P = NS) by first pass and equilibrium determinations respectively. In comparison the LVEF during peak supine bicycle exercise decreased significantly to 42 +/- 12% (P less than 0.01). In nine patients with angiographically normal coronary arteries the rest LVEF was 51 +/- 4% by first pass and 54 +/- 6% by equilibrium, increasing to 67 +/- 7% (P less than 0.01) and 64 +/- 7% (P less than 0.01) respectively following treadmill exercise. During peak bicycle exercise LVEF increased in the normal patients to 61 +/- 7% (P less than 0.05). These data suggest that quantitative radionuclide angiography following either maximum treadmill exercise or during peak bicycle exercise can discriminate between patients with coronary artery disease and normal subjects, although the magnitude of left ventricular functional changes are greater during bicycle stress.

An oral examination of the psychiatric knowledge of medical housestaff: assessment of needs and evaluation baseline

To assess the psychiatric knowledge of medical housestaff, the authors devised an oral examination based on two simulated clinical encounters and administered it to 26 medical residents. The case material embodied those psychiatric problems known to be common in medical populations, namely depression, delirium, dementia, and "psychogenic" pain. The standardized simulations were punctuated by standardized "open" questions with followup probes. A panel of experienced clinicians developed rating criteria for each question such that responses could be categorized ad "good," "adequate," "inadequate," or "poor," in terms of "what an internist needs to know." Blind raters of the exam achieved an interrater reliability of 0.08. The results indicate major deficits in the knowledge needed for assessment and treatment of these common problems. Only 16% of answers were "good," where as 42% were "inadequate" or "poor". For example, 88% of the doctors could not name three factors that help distinguish organic from "functional" psychosis, and 88% could not list three side-effects of tricyclic antidepressants. The doctors' level of experience was not correlated with test scores, either overall or question by question. These results, together with measures of attitude and skill, have been used to develop a needs-based liaison psychiatry curriculum and to evaluate the effectiveness of that curriculum.

Time trend analysis of plasma unconjugated and sulfoconjugated estrone and 3 beta-delta 5-steroids in fetal and maternal sheep plasma in relation to spontaneous parturition at term

Parturition in the sheep is preceded by a complex series of changes in both fetal and maternal plasma-steroid hormone concentrations. Using the chronically catheterized fetal sheep preparation, we measured unconjugated and sulfoconjugated pregnenolone, 17 alpha-hydroxypregnenolone, dehydroepiandrosterone, and estrone in fetal and maternal plasma over the final 20 days before spontaneous vaginal delivery at term. Where appropriate, third degree polynomial functions were fitted to the changing plasma hormone concentration profile. Fetal and maternal plasma pregnenolone and pregnenolone sulfate both fell from maximum values in the last 4 days of gestation. Fetal and maternal plasma estrone and estrone sulfate concentrations underwent a terminal rise over the last 4 days of gestation that was a mirror image of the fall in plasma pregnenolone and pregnenolone sulfate. Maternal 17 alpha-hydroxypregnenolone rose over the last 4 days of gestation. Fetal 17 alpha-hydroxypregnenolone, maternal and fetal plasma dehydroepiandrosterone sulfate, and fetal plasma dehydroepiandrosterone sulfate, and fetal plasma dehydroepiandrosterone showed no trend during the period of study. Maternal plasma dehydroepiandrosterone rose over the last 4 days of gestation. These results support the view that increased activity of placental 17 alpha-hydroxylase and 17-20-desmolase is responsible for the conversion of C-21 steroids to estrogens at term. delta 5-Steroids are present in very high plasma concentrations in fetal sheep plasma and may constitute a more important precursor pool for estrogen biosynthesis than does circulating plasma progesterone.

The influence of histologic type on the incidence and duration of response in non-Hodgkin's lymphoma

A group of 227 cases of non-Hodgkin's lymphoma included seven favorable and four unfavorable histologic classes with collective median survival times of 83 and 16 months, respectively. The favorable group included three follicular subgroups (cleaved, mixed, and large noncleaved) and four diffuse classes (small lymphocytic, cleaved, Burkitt's noncleaved, and convoluted lymphocytic). The unfavorable group consisted of four diffuse subgroups (plasmacytoid lymphocytic, mixed, and small and large noncleaved). There were significant differences in collective median survivals between patients in Stage I--II and those in Stage III--IV in both the favorable group (not reached, NR versus 62 months, P less than 0.001) and the unfavorable group (57 months versus 12 months, P less than 0.01). The incidence of complete response to primary treatment was higher in the favorable than in the unfavorable group (75% versus 56%, P = 0.002) and in those with limited as compared with advanced disease. Complete responders in both prognostic groups had longer survival times than did partial or minimal responders. A significant difference in median complete remission duration was found between responders in Stage I--II versus Stages III-IV in the favorable group (not reached versus 40 months, P = 0.001) but not in the unfavorable one (56 months versus 22 months, P greater than 0.05). The absence of relapses after 41 months among complete responders in the favorable but not in the unfavorable group suggests a potential for cure in a proportion of cases from the former group. The incidence of complete response was lower and median remission duration was shorter after secondary as compared with primary treatment. The results of this study confirm the prognostic value of the Lukes and Collins classification system and the importance of initial staging and of achieving a complete response to primary treatment in both the favorable and unfavorable lymphomas.

First-pass radionuclide angiocardiography in the determination of left-to-right cardiac shunt site in children

To ascertain if the level of a left-to-right cardiac shunt can be reliably established by first-pass radionuclide angiocardiography with 99mTc-pertechnetate, 102 children have been studied; 19 without a shunt, 26 with an atrial septal defect (ASD), 45 with a ventricular septal defect (VSD), and 12 with a patent ductus arteriosus (PDA). Time-activity curves were generated over the right atrium and ventricle, and several quantitative parameters were derived from the curves. It was concluded that in the absence of right-sided valvular incompetence, the time-activity curves show the greatest abnormality in the cardiac chambers distal to the left-to-right shunt. The right ventricular curve is typically altered in ASD but cannot be relied upon to differentiate VSD or PDA. The identification of ASD is assisted by the use of two of the parameters, the count ratio C4:C1 and time ratio T2-T1.

Intrathecal interferon reduces exacerbations of multiple sclerosis

Ten patients with multiple sclerosis who were treated with human fibroblast interferon (IFN-B) for 6 months showed a significant reduction in their exacerbation rates compared with their rates before treatment (P < .01). The IFN-B was administered intrathecally by serial lumbar punctures. There was no significant change in the exacerbation rates of ten multiple sclerosis control patients before and during the period of observation. The IFN-B recipients have now been on the study a mean of 1.5 years, the controls, 1.2 years. The clinical condition of five of the IFN-B recipients and one of the control patients has improved, whereas the condition of five of the controls and one of the IFN-B recipients has deteriorated (P < .036). These findings warrant cautious optimism about the efficacy of intrathecal IFN-B in altering the course of multiple sclerosis and support concepts of a viral or dysimmune etiology of the disease.