Islet transplantation: clinical and experimental.

Experimental diabetes in rodents has been successfully treated by implantation of isolated islets using a syngenic system (Lewis rats). It is possible to reverse all diabetic symptoms of the animals and to prevent late complications in kidney, eye and nervous system. Although isolated islets are highly immunogenic in an allogenic system immuno-alteration techniques have been developed and succeeded in longterm survival after culture at low temperature (24 degrees C), UV-irradiation, cryopreservation, pretreatment with Ia-antibodies etc. Islet transplantation in larger animals and in man up to now has been less successful. Although in a few studies longterm survival of canine islets has been observed, other groups were less successful using dogs and pigs in auto- or allo-transplantation. In man there are reports from various institutions during the last fifteen years using adult or fetal islet material. Only in a few instances the patients came off insulin for some weeks or months. The reasons for this failure are probably manifold: low number of islets, impurity, long ischemia time before isolation, transplantation to inappropriate sites, impairment of engraftment in longterm diabetic recipients and recurrence of autoimmunity in transplanted islets. Further studies are necessary to overcome these barriers. Recent observations using a higher number of islets (> 500,000) and new immunosuppressive drugs (FK506) seem to be promising.


Delayed activation of D-glucose transport in type II diabetes mellitus.

Peripheral insulin resistance is suggested to play an important role in the pathogenesis of type II diabetes mellitus. In this study we investigated insulin receptor binding, D-glucose transport under equilibrium conditions for insulin and the activation kinetics of insulin stimulated D-glucose transport in isolated human adipocytes from type II diabetics and healthy controls. While the insulin receptor binding affinity was not significantly different between both groups, basal and insulin stimulated glucose transport rates were reduced in adipocytes from type II diabetics compared to normal controls. The activation of D-glucose transport was significantly delayed in the diabetics, the time to achieve maximal transport rates was 7.7 +/- 1.1 vs. 4.2 +/- 1.4 min, respectively (p < 0.05). Thus a reduced velocity of glucose transport activation by insulin appears to be a further factor contributing to peripheral insulin resistance in type II diabetics.


Effect of the infusion of p-Glu-His-Ala-OH, analog of the anorexigenic peptide, on the insulin response induced by intravenous glucose. Preliminary results with obese subjects.

The effect of the intravenous infusion of peptide p-Glu-His-Ala-OH, analog of the postulated anorexigenic peptide, on the insulinaemic response to an intravenous bolus of 20 g glucose was studied in 6 obese patients (body mass index 43.12 +/- 5.77 kg/m2). The infusion of the peptide reduced the insulinaemic response (p < 0.05) without modifying either the C-peptide or the glucose response. This decreased insulinaemic response is associated with a greater hepatic extraction of insulin (86.45 +/- 1.1% vs 82.1 +/- 1.2%; p 0.05), determined in terms of the molar ratio of the C-peptide to insulin) but not with a smaller pancreatic secretion (determined as C-peptide levels). Our results confirm that the infusion of the peptide increases the hepatic insulin extraction without its effect being mediated by any intestinal factor. Its therapeutic application remains to be determined.


Improvement of glucose tolerance by minimal doses of glipizide in obese subjects with different degrees of glucose intolerance.

Obesity and impaired glucose tolerance (IGT) are risk factors for non insulin dependent diabetes mellitus (NIDDM) and for ischemic heart disease. Long term treatment of IGT subjects with diet and tolbutamide prevents progression of IGT to NIDDM. We have evaluated the lowest dose of glipizide, a second-generation sulfonylurea, able to improve glucose tolerance in response to oral glucose in 31 obese subjects, 12 with NIDDM, 9 with IGT and 10 with normal glucose tolerance (NGT). All subjects underwent four OGTTs, preceded by placebo and by different doses of glipizide (0.5, 1.0, 2.5 mg). Glucose tolerance was progressively improved by increasing glipizide doses in all groups, probably by peripheral mechanism and by enhanced insulin release.


Efficacy of 6 months monotherapy with glucosidase inhibitor Acarbose versus sulphonylurea glibenclamide on metabolic control of dietary treated type II diabetics (NIDDM).

Six months monotherapy with Acarbose vs. glibenclamide led to a marked improvement of BG and HbA1 in NIDDM, insufficiently controlled with diet. Beneficial effects of these distinct principles of action were statistically not different.


Value of fasting blood glucose and serum fructosamine as a measure of diabetic control in non-insulin-dependent diabetes mellitus.

The predictive values of fasting blood glucose and serum fructosamine for monitoring longterm diabetic control were investigated in 98 non-insulin dependent diabetic patients. The HbA1c percentage was taken as standard in this study. Despite a significant correlation, the predictive values of the parameters studied for an acceptable HbA1c-value appeared to be low (37% and 44% respectively), possibly due to differences in periods of time in which these parameters can change during variable metabolic control. In addition, the serum fructosamine value may vary due to variations in serum albumin and lipid content. It is concluded that the fasting blood glucose and serum fructosamine values cannot replace HbA1c measurement for monitoring diabetic control, but are additional for assessment of this control over short-and longterm periods of time.


Diabetic retinopathy, nephropathy and neuropathy. Generalized vascular damage in insulin-dependent diabetic patients.

The most serious complication of diabetes mellitus is clinical nephropathy. The development of persistent proteinuria (urinary excretion of more than 300 mg albumin/24 hours) implies an extremely high risk of early death. Renal failure is the most frequent cause of death but the mortality of cardiovascular diseases is also increased. Besides the link between albuminuria (nephropathy) and atherosclerosis in coronary arteries, albuminuria is also a predictor of microangiopathy in other organs than the kidneys. The annual incidence of proliferative retinopathy in early nephropathy is 10-15% compared to only 1% in patients without nephropathy. Also signs of cardiomyopathy have been demonstrated in early nephropathy. Further we have described markers of universal endothelial damage in these patients, and we hypothesize that albuminuria not only is a predictor of renal disease but also of widespread vascular disease. Long-term improvement of metabolic control by use of insulin infusion pumps and early antihypertensive treatment seem to stop the further progression of early diabetic nephropathy and to significantly improve the prognosis of clinical nephropathy.


Screening for micro-albuminuria with Micro-Bumintest tablets and albumin/creatinine ratio.

The value of Micro-Bumintest tablets and the albumin/creatinine ratio in first morning (FM) urine samples to screen for micro-albuminuria in diabetic patients was evaluated. The A/C ratio in FM urine was highly correlated with the urinary albumin excretion (UAE) rate in micrograms/min in timed overnight (0) urine (R = 0.95, p < 0.001). The sensitivity, specificity and positive and negative predictive values of an A/C ratio > 3.0 to predict micro-albuminuria defined as an UAE > 20 micrograms/min were 94, 92, 92 and 94% respectively. The day-to-day fluctuation of albumin excretion varied between 10 and 105%. The sensitivity, specificity and positive and negative predictive values of micro-bumintest tablet reactions on FM urine samples to predict an A/C ratio > 3.0 were 93, 59, 63 and 91% respectively. It is concluded that for screening of micro-albuminuria the A/C ratio in FM urine is as precise as timed 0 urine collection, but with more comfort for the patient. Micro-Bumintest tablets are useful as an initial screening test and will decrease the number of quantitative albumin measurements in the screening programme by about 30% if only urine samples with positive tablet test are selected for a further investigation. Because of considerable day-to-day fluctuation of urinary albumin excretion several urine samples should be investigated before presence of incipient diabetic nephropathy is assumed.


The prevalence of diabetes mellitus and other risk factors of atherosclerosis in bradycardia requiring pacemaker treatment.

258 patients with pacemakers (PM) were examined retrospectively; 126 (48.8%) had second- or third-degree av-block (AVB), 43 (16.7%) atrial fibrillation with bradycardia (AFB), 63 (24.4%) sick sinus syndrome (SSS) and 26 (10.1%) other indications (OI). Control persons (CP) of same age and sex with regular sinus rhythm were recruited from in-patients of our hospital. Diabetes was found in 127 (49.2%) of PM (of adult onset only) and in 99 (38.4%) of CP (3 of juvenile onset; p < 0.025), in 68 (53.9%) of the patients with AVP (p < 0.05), 24 (55.8%) with AFB, 21 (33.3%) with SSS (n.s.) and 14 (53.8%) with OI (n.s.). Obesity was positively correlated concerning the entire PM group, blood pressure and smoking habits showed no correlation, cholesterol and triglycerides were inversely correlated (p < 0.05 up to p < 0.001). Myocardial infarction showed no difference between PM and CP, digitalis and diuretics were taken significantly more often (p < 0.001) by PM. We conclude that diabetes mellitus is a major risk factor for av-block of higher degree and atrial fibrillation with bradycardia, which is not influenced by other, diabetes-related risk factors of atherosclerosis.


Autonomic neuropathies in skin and its incidence in non-insulin-dependent diabetes mellitus.

The autonomic function of nerve fibres was investigated with the newly developed hyperthermal Laser-Doppler-Flowmetry in 45 patients suffering from Non-Insulin-Dependent Diabetes Mellitus (NIDDM). They were divided into 3 groups depending on the duration of NIDDM. Group A contained a duration of 1-3 years, group B 4-5 years and group C 5-6 years. All groups showed a dysfunction of autonomic nerve fibres: in group A there were 4 of 11 patients, in group B 2 of 13 and in group C no patients with values within the normal ranges. So autonomic neuropathies of skin seem to be one of the earliest complications in NIDDM


Diabetes mellitus and bone metabolism.

Whether there is a diabetic osteopathy" or osteopathy in diabetes mellitus", is still unclear. Epidemiological studies show in part discrepant results: bone mass was diminished in some studies, unchanged in others--even more positive trends were reported. Increases in osteoporotic fractures were observed in smaller collectives whereas no general trends for fracturing bones were found in diabetics. There are many in part favouring, in part impairing factors to be taken into consideration: Diabetes mellitus type I is a disease including immune phenomena. As inflammation leads to bone loss (inflammation-mediated osteopenia = IMO), peak bone mass may be influenced by such a process. The lack of insulin-like growth factors may be decisive, too. Complications of diabetes mellitus include hypogonadism--this may be disadvantageous for the skeleton. Diabetic complications like retinopathy, neuropathy, and angiopathy may influence the fracture event independently from bone mass. On the other hand, diabetes mellitus type II may be somehow protected against bone loss: Increased adipose tissue in connection with the frequently seen overweight yields metabolically active steroid hormones, insulin related growth factors may stimulate bone formation (e.g. in Forestier's disease). Older diabetics do not show diminished life expectancy any more due to their regular medical care--whether this includes the risk of bone diseases, is not yet clear. It may be worth to further analyse these "positive" effects seen in bones of type II diabetics because they may be useful in osteoporosis even in non-diabetics.


Increased platelet activity in diabetic macroangiopathy.

In order to investigate the relationship between the in vivo platelet activity and diabetic macroangiopathy we have measured plasma beta-thromboglobulin (beta-TG) concentrations by means of a very sensitive radioimmunoassay in 55 diabetics, aged 47-80 years, and in 27 non-diabetic healthy controls (group A) of respective age and sex. Among diabetics 17 were free of vascular complications (group B) in terms of diabetic micro- or macroangiopathy, while the remaining 38 (group C) suffered from peripheral occlusive arterial disease (POAD) of the lower limbs. All subjects underwent a thorough clinical and laboratory investigation. The diagnosis of POAD was based upon the findings of Doppler ultrasound examination and was confirmed by selective arteriography. The mean plasma beta-TG concentrations were significantly higher in the two groups of diabetics compared to the non-diabetic controls (p < 0.001), whereas the highest beta-TG levels were found in diabetics with POAD (py 0.001), (beta-TG: mean +/- 1 SD ng/ml; group A: 26.50 +/- 13.14; group B: 55.88 +/- 26.56; group C: 106.50 +/- 52.65). These findings reveal an increased release reaction of platelets in diabetics and an enhanced in vivo platelet activity especially in POAD subjects. However, this may occur not only in cases with prominent macroangiopathy but also in the early stages of diabetic angiopathy when the vascular lesions cannot be traced clinically.


More lessons, of a different kind: Canadian mental health policy in comparative perspective.

Many health policy reformers and researchers in the United States have focused on the Canadian health care system and its lessons for design of a national health care program in the U.S. Yet minimal attention has been given to Canadian mental health policy in this discussion. The author reviews the historical development of mental health services in Canada and discusses five current sources of tension in Canada's mental health care system, many of which are familiar to the American setting: restriction on fee-for-service payments, a two-tiered pattern of care involving provincial mental hospitals and general hospital psychiatric units, shortages of mental health care resources, limited funding of community-based programs, and lack of coordination of care. The author concludes that universal insurance coverage patterned after the Canadian model would ameliorate only some problems faced by mentally ill persons in the United States. Mental health benefits must be structured to ensure the availability and organization of a full spectrum of long-term health care and supportive services.


The fate of mental health services in health care reform: I. A system in crisis.

The U.S. health care system is in the midst of a severe crisis. More than 50 million Americans are uninsured or underinsured. Medicare and Medicaid are not adequately serving populations in need. Analyses and reform proposals are often based on biased interpretations of data, resulting in confusion and heated debate. To avoid jeopardizing psychiatric care in a national health care reform movement, we must understand the causes of the national crisis. In the first part of a two-part paper, the author describes factors such as demographic trends and limitations in public health coverage that have contributed to the crisis. Outcomes of the current system include higher morbidity and mortality among the uninsured and a high prevalence of untreated illness. The author reviews direct and indirect costs of health care and concludes that in attempts to solve the difficult equation of access, cost, and quality, mental health services are in serious jeopardy.


The fate of mental health services in health care reform: II. Realistic solutions.

In the second part of a two-part paper, the three major proposals for U.S. health care reform--the government-sponsored model, the employment-based model, and the market reform model--are reviewed. Barriers to their success include the current economic crisis, the lack of a clear consensus, and the high costs of the proposals. Most proposals limit the extent of psychiatric coverage; some exclude such coverage from minimum benefit packages, an area of concern for clinicians. The author concludes that any substantial health care reform is unlikely in the near future. A thoughtful, realistic, and yet vigorous strategic plan is needed now to forestall the possible exclusion of significant mental health coverage. The basic elements of such a plan are reviewed.


Mental health care in Japan.

Long-term institutionalization has been the primary treatment for mentally ill patients in Japan since the early 1920s. The average length of stay in a Japanese mental hospital in 1989 was 496 days, 41 times the average stay of patients in the United States. Although the government has encouraged and supported the integration of mentally ill people in the community and the development of rehabilitation programs since enactment of the Mental Health Law of 1988, implementation of such programs has been slow. The authors summarize the history of mental health care in Japan, discuss the current availability of mental health care facilities and personnel, and recommend changes needed to improve care.


Determinants of equality and equity for special populations served by public mental health systems.

Within the publicly funded mental health service delivery system, debate continues over what constitutes a fair and just system for special populations. To determine a system's fairness, the author proposes a conceptual framework in which two standards of fairness--equality and equity--are applied to three dimensions of a mental health system: utilization of services, funding for services, and access to services. An equal system assumes that rates of mental illness and needs for treatment are the same for all subgroups of the general population; funds are allocated and services are offered accordingly. An equitable system assumes that special populations have different rates of mental illness and different treatment needs; funds are allocated and programs are designed based on the recognition of these differences. The author argues that the publicly funded mental health service system must establish equitable, rather than equal, services for special populations.


A voucher system that enables persons with severe mental illness to purchase community support services.

Fragmentation in the delivery of community support services is often identified as a major barrier to persons with severe mental illness, preventing them from living productive lives in the community. In Nassau County, New York, in 1989 a voucher process was created to allow service users to develop individualized support networks by purchasing services directly and by pooling funds to start new services. The voucher process is part of an intensive case management program. Goals set in the individual service plans of users guide voucher purchases. The local Mental Health Association manages funds based on a bank credit card model. The user, the case manager, and a staff member from an agency designated by the user review expenditures quarterly. The first year of operation is described, and suggestions for developing a voucher process, such as the need for extensive retraining of users and providers, are offered.


The role of general hospitals in the privatization of inpatient treatment for serious mental illness.

For almost three decades, many have regarded general hospital psychiatric units as the most appropriate setting for acute treatment of persons with serious mental illness who were once treated mostly in state hospitals. The extent to which this transfer has taken place and the differences between public and private general hospitals have been unclear. Using data from the 1988 National Mental Health Facilities Study and published data from the 1970s, the authors found that nearly half of all general hospitals providing psychiatric services treat persons with serious mental illness. Significant differences in case and payer mix were observed between public and private general hospitals, although these differences were smaller than in the 1970s. The findings suggest increased involvement by private general hospitals in treating patients reimbursed by public payers, but the findings also indicate that persons with serious mental illness and those using Medicaid are still more prevalent in public general hospitals than in private ones.


Case-based reimbursement for psychiatric hospital care.

A fixed-prepayment system (case-based reimbursement) for patients initially requiring hospital-level care was evaluated for one year through an arrangement between a private nonprofit psychiatric hospital and a self-insured company desiring to provide psychiatric services to its employees. This clinical and financial experiment offered a means of containing costs while monitoring quality of care. A two-group, case-control study was undertaken of treatment outcomes at discharge, patient satisfaction with hospital care, and service use and costs during the program's first year. Compared with costs for patients in the control group, costs for those in the program were lower per patient and per admission; cumulative costs for patients requiring rehospitalization were also lower. However, costs for outpatient services for patients in the program were not calculated. Treatment outcomes and patients' satisfaction with hospital care were comparable for the two groups.


Reorganization of a private psychiatric unit to promote collaboration with managed care.

Managed care organizations have become significantly involved in health care in the Denver metropolitan area. Their presence has challenged psychiatric hospitals to reduce costs and length of stay. In 1990, a locked private psychiatric unit was reorganized into locked, open, and partial care services through which patients progress at individualized rates. One treatment team manages patients in all settings, allowing a reduction in staffing costs and flexibility in treatment design. The hospital administration takes an active role in facilitating collaborative decision making between hospital clinicians and managed care representatives. In the first year after reorganization, length of stay was significantly reduced; 90 percent of patients were discharged from 24-hour care within ten days or less, whereas only 40 percent were discharged within that time in the original program. Staffing costs were reduced by 15 percent. No increase in recidivism was noted.


[Bacterial infections in pregnancy].

The spectrum of bacterial infections during pregnancy is broad. Among blood-transmitted infections especially listeriosis endangers the child. More frequent are ascending and peripartal infections, which imperil both mother and child. The disturbed vaginal flora, which occurs in 10-30% of all pregnant women, has to be regarded as its reservoir. Cervicitis caused by gonococci or chlamydiae, but also high concentrations of facultative pathogenic bacteria are regarded as the main cause of the preterm rupture of membranes leading to preterm delivery. Especially feared is the group-A-streptococci infection, which appears more frequently. In 5% of all pregnant women a chlamydial cervicitis is found.


[Acellular pertussis vaccines].

Each vaccine is normally rated according to its efficacy and to the frequency and severity of unwanted side effects. The efficacy of whole-cell pertussis vaccines is beyond doubt, its frequent side effects, however, stimulated research into less reactogenic acellular vaccines. Several acellular pertussis vaccines of different composition have been developed. All of these produced significantly less local and systemic side effects, as compared to the conventional whole-cell vaccine. Various epidemiological data strongly suggest the efficacy of these vaccines. An equivalence of protective efficacy between whole-cell vaccines and acellular pertussis vaccines can, however, only be documented in controlled field trials, which are now ongoing in several countries.


[Infections by Streptococcus pyogenes: new aspects of diagnosis, epidemiology, clinical practice, and therapy].

Essential procedures for the cultural and serological laboratory diagnosis of Streptococcus pyogenes are described. A reliable and rapid species identification is achieved by serologic or biochemical tests. Direct antigen detection tests from throat swabs have broadened the diagnostic possibilities; however, they are often not satisfactory in terms of sensitivity. Typing of strains (either by classic serologic techniques or by molecular methods) is of high value for the study of clinical and therapeutic questions. In recent years, the epidemiology of the prevalent group A streptococcal strains has changed in Europe as well as in the U.S.: an increase of those M protein serotypes that are associated with higher virulence is being recognized. There is good evidence that the unexpected resurgence of rheumatic fever in the U.S. and the emerging number of life-threatening invasive and toxic manifestations of disease (including the toxic shock syndrome) in the U.S. and in Europe are related to the changing epidemiology. The existence of strains with rheumatogenic and nephritogenic potency has been established, but genetic host factors are a prerequisite for the sequelae as well. Although, based on experimental data, there are a lot of hypotheses concerning the nonsuppurative sequelae and the toxic shock syndrome, the exact pathogenesis of these diseases remains to be clarified. A thorough knowledge of the various clinical manifestations of group A streptococcal infections is necessary in order to apply the therapeutic and preventive measures in a rational and sophisticated manner. For most infections penicillins are considered the drug of choice, although no final conclusions regarding optimal dosages or the reasons for treatment failures can be made.(ABSTRACT TRUNCATED AT 250 WORDS)


[New strategies for the prevention of foreign body infections].

Foreign body infections continue to present a challenge to modern medicine. New aspects for the prevention of such infections are presented on the basis of modifying medical devices or implant materials (synthetic polymers). Physicochemical treatment of polymer surfaces is a possible tool to create anti-adhesive and thus anti-infective surfaces. Coupling or incorporation of antimicrobial substances to or into polymers is another way to prevent bacterial colonization and subsequently the development of polymer-associated infections.


Binding of a membrane proteoglycan from Klebsiella pneumoniae and its derivatives to human leukocytes.

The binding of a membrane proteoglycan from a non-encapsulated strain of Klebsiella pneumoniae (Kp-MPG) and four derivatives thereof, to human leukocytes, was investigated by indirect immunofluorescence using biotinylated F(ab')2 fragments of anti-Kp-MPG antibodies and the streptavidin-phycoerythrin amplification system in flow cytometry. Four Kp-MPG derivatives were studied: 1/ an acylpoly(1,3)galactoside (APG), 2/ an APG preparation submitted to acid hydrolysis which removed all fatty acids, but left intact the galactose chain of APG (GC-APG), 3/ a preparation obtained by mild alkaline hydrolysis, containing additional ester-linked C14 and C16 fatty acids bound to the APG molecule (EFA-APG) and 4/ a polymer of the latter compound (APG pol). Kp-MPG, APG and EFA-APG were shown to bind exclusively to monocytes at the lowest concentrations (from 0.15 to 3 microM APG). At higher concentrations, these compounds interacted with polymorphonuclear leukocytes, and with lymphocyte subsets in the following decreasing order: B cells, NK cells, CD8+ and CD4+ lymphocytes. Neither APG pol or GC-APG nor K. pneumoniae smooth LPS showed significant binding to leukocytes. However Kp-LPS treated by drastic alkaline hydrolysis displayed binding properties similar to those of APG. Removal of the ester-linked C14 and C16 fatty acids from EFA-APG did not affect the binding of the molecule. The capacity of cells from the myelomonocytic lineage to bind Kp-MPG and APG was very low in phenotypically immature cell lines (HL60 and U937) as compared with monocytes or polymorphonuclear cells. Treatment of U937 cells with interferon-gamma up-regulated their APG binding capacity along with the expression of the integrin CD 11 b and the CD 14 molecule, whereas monocytes exposed to interferon-gamma showed an increased binding of APG associated with an elevated expression of the galactose specific lectin Mac-2. The data demonstrate a preferential binding of Kp-MPG and APG to cells of the monocyte/macrophage lineage. APG binding does not involve the poly (1,3) galactose chain and the ester-linked C14 and C16 fatty acids but requires the presence of the hydrophobic part of the molecule.


Indirect and selective down-regulation of serum tumor necrosis factor-alpha release by interleukin-1 beta.

A selective inhibition of LPS-induced tumor necrosis factor-alpha (TNF) response in mice was caused by an injection of recombinant human interleukin-1 (IL-1). The decrease in serum TNF level reached 70 to 80 percent of the controls receiving LPS alone when IL-1 was given simultaneously or prior to the challenge. At the same time serum IL-6 release was more elevated. Ex vivo assays have shown that macrophages from IL-1 treated animals did not respond to LPS when stimulated immediately after harvesting but recovered their normal responsiveness after being cultured for 2 hours and then washed. In vitro with or without addition of IL-1, mouse elicited macrophages responded equally to LPS in releasing TNF. In the absence of a direct and lasting effect on TNF-producing cells, the host reaction responsible for the inhibitory effect of IL-1 could be related to the overproduction of corticosterone that occurred after IL-1 injection, since it was not observed in adrenalectomized animals. Indeed the blockade of corticoid secretion by indomethacin prevented the inhibition of TNF production induced by IL-1 administration before LPS challenge. TNF administration did not result in elevation of corticosterone level and in contrast to IL-1 enhanced the TNF response to LPS injection. In vitro and ex vivo assays have shown this enhanced response to LPS was linked to a direct and prolonged effect of TNF on TNF-producing cells. Muramyl dipeptide (MDP) which was used as a known priming agent for enhanced cytokine release had a similar effect on TNF-producing cells.(ABSTRACT TRUNCATED AT 250 WORDS)


Effector cells of low-dose IL-2 immunotherapy in tumor bearing mice: tumor cell killing by CD8+ cytotoxic T lymphocytes and macrophages.

The presence and cytotoxicity of tumor infiltrating cells is described in mice during effective immunotherapy with interleukin 2 (IL-2). DBA/2 mice were inoculated i.p. with 2 x 10(4) tumor cells on day 0 and treated with daily i.p. injections with 20,000 units IL-2 on days 10-14. Mice bearing a large syngeneic i.p. tumor burden (SL2 lymphoma, P815 mastocytoma, L5178Y lymphoma, or L1210 lymphoma) could be cured by i.p. immunotherapy with these low doses of IL-2. In the peritoneal cavity of these mice an infiltrate of mononuclear cells was present. Similar numbers of lymphocytes (10(6)-10(7)) and macrophages (+/- 10(7)) were present in control tumor bearing mice and IL-2 treated tumor bearing mice. The ratio of CD4+/CD8+ T lymphocytes in the peritoneal cavity of mice rejecting the SL2 tumor was smaller than 0.5, whereas this ratio is about 2 in naive mice. In the spleens of IL-2 treated tumor bearing mice only a minor decrease of CD4+/CD8+ ratio was observed from 2.1-2.4 to 0.9-1.9. T cells isolated from the peritoneal cavity of mice inoculated with SL2 tumor cells and treated with IL-2, were highly cytotoxic to SL2 cells: at E:T ratio 2:1 the cytotoxicity index was 37 +/- 3. This cytotoxicity was specific and mediated by CD8+ T lymphocytes. Macrophages that were present in the peritoneal cavity of mice treated with IL-2 were also highly cytotoxic. The C.I. of these cells was 63-76% at E:T ratio 1:1. Cytotoxic macrophages were also present in untreated tumor bearing mice. The i.p. injections of IL-2 (20,000 units/day) caused a four-fold increase in the local NK-activity in the peritoneal cavity in naive mice. These IL-2 injections did not generate LAK-activity in vivo. Specificity of the in vivo tumor rejection was tested by injection SL 2 i.p. on day 0 and P815 i.p. on day 10, or vice versa, followed by IL-2 treatment. Only the tumor cells that were injected on day 0 were rejected. These in vivo experiments point to specific tumor rejection. In conclusion, both cytotoxic macrophages and CTL's are present in a sufficient number and with sufficient cytotoxicity to explain the killing of tumor cells in the peritoneal cavity. The CTL-activity seems of decisive importance for tumor rejection as this is induced by IL-2.


Induction of an increased number of dendritic cells in the peritoneal cavity of rats by intraperitoneal administration of Bacillus Calmette-Guérin.

Recently we described the presence of a small number of DC among the peritoneal cells of steady state rats. These DC had the same morphological characteristics and a similar antigen-presenting capacity as DC isolated from the spleen. This study shows that in the peritoneal cavity, which is a non-lymphoid microenvironment, the number of DC increases after i.p. administration of BCG. Next to this relatively small influx of DC, the approximately three-fold increase of the total number of cells is predominantly caused by an enormous influx of neutrophilic granulocytes, and to a lesser extent by an influx of macrophages. The phenotype and the antigen-presenting capacity of peritoneal DC has not changed, while the number of Ia-positive M phi has increased. Nevertheless, due to a suppressive effect of the peritoneal M phi, the total peritoneal cell suspension is no longer capable of presenting antigen.


Induction of cytokines in human whole blood cultures by a mitogen derived from Mycoplasma arthritidis and by staphylococcal enterotoxin B.

Mycoplasma arthritidis produces a so-far only partially characterized soluble material (MAS) that has a potent mitogenic effect on T lymphocytes of several species. Similar to staphylococcal enterotoxins and a number of related toxins secreted by other species of bacteria, nanogram quantities of these so-called superantigens are sufficient to induce significant amounts of cytokines in the supernatant of lymphocyte cultures. Induction of interleukin-6 (IL-6) by MAS in murine bone marrow-derived macrophages has recently been described. In our study, we examined the differential effects of MAS and Staphylococcus aureus enterotoxin B (SEB) on human blood cells. When compared to MAS, SEB induced a higher proliferative response and, accordingly, a higher release of IFN-gamma. In contrast, large amounts of the macrophage products IL-1, IL-6 and tumor necrosis factor alpha (TNF-alpha) were observed in supernatants of cell cultures stimulated with MAS, whereas only small amounts were induced by SEB. Staphylococci and mycoplasmas are responsible for a number of diseases with various symptoms in man and animals. Our results suggest that SEB and MAS show different qualities in lymphocyte and macrophage stimulation which may be relevant in the pathogenesis of diseases.


Expression of murine soluble CD4 protein in baculovirus infected insect cells.

The expression of murine soluble CD4 (L3T4) protein (sCD4) by baculovirus-infected insect cells was characterized. The yield of sCD4 reached 2 mg/l culture supernatant late in infection. Nevertheless, a large amount of sCD4 remained cell-associated, presumably in the endoplasmic reticulum or an early golgi compartment, as indicated by the endo-beta-N-acetyl-D-glucosaminidase H (endo-H) sensitivity of its carbohydrate chains. The secreted form of sCD4 is modified with both endo-beta-N-acetyl-D-glucosaminidase D (endo-D) and endo-H-sensitive oligosaccharides. It was possible that the incomplete secretion indicated faulty glycosylation or improper folding of the sCD4 protein. However, inhibitor studies showed that complete carbohydrate processing is not required for secretion of sCD4 by insect cells. Moreover, maintained reactivity with a panel of monoclonal Ab as well as phase partitioning experiments suggested that secretion is apparently not caused by misfolding of the sCD4 protein. Similar results were obtained with biologically active murine interleukin-4 produced by insect cells. This indicates that an inefficient secretory pathway may be a general problem of baculovirus-infected insect cells and is not a consequence of incorrect molecular conformation.


Quantitative analysis of MEL-14 expression on various lymphocyte subpopulations.

Amounts of gp90MEL-14 molecules in various lymphocyte subpopulations were analyzed. The expression of gp90MEL-14 was rapidly up-regulated in the course of usual procedures for preparing single cell suspensions. On the other hand, the gp90MEL-14 expression was down-modulated after short term culture in the presence of PMA. Addition of NaN3 in the medium for preparing cell suspension was shown to stabilize the expression profile of the gp90MEL-14. By this simple improvement, we could successfully evaluate the precise amounts of gp90MEL-14 expressed on various lymphoid cells which appeared to reflect the expression pattern of gp90MEL-14 in vivo. The proportion of MEL-14+ cells and amounts of gp90MEL-14 on the cells were clearly associated with the anatomical and functional distance from endothelial cells of HEV in peripheral lymph nodes. The present findings, thus, support the role of gp90MEL-14 molecules as homing receptors for HEV that was originally proposed by Weissman and his colleagues.


Comparison of tolerance inducibility to class I or class II antigens between cyclophosphamide (CP)-induced tolerance and transfusion with donor cells: general effectiveness of CP-induced tolerance and difference of skin graft prolongation in each class I antigen-disparate combination.

Transfusion with allogeneic cells alone was reported to prolong skin allograft survival in the MHC class I antigen alone-disparate combination of B6.C-H-2bm1 (bm1; Kbm1, IAb, IE-, Db)-->C57BL/6 CrSlc (B6; H-2b). Using 6 class I antigen-disparate and 2 class II antigen-disparate combinations, we compared the effectiveness for skin graft prolongation between transfusion with donor cells (TDC) and our system of CP-induced tolerance, which comprises intravenous (i.v.) injection of allogeneic cells followed by cyclophosphamide (CP), i.e., TDC followed by CP. TDC was effective only in the combination of bm1-->B6, but not at all in the other combinations. On the other hand, CP-induced tolerance was effective in the 5 class I antigen-disparate and 2 class II antigen-disparate combinations except for bm1-->B6 combination. These results suggest that CP-induced tolerance may be more general for the induction of unresponsiveness than TDC.


The cytotoxic T lymphocyte response in reticuloendotheliosis virus-infected chickens is mediated by alpha beta and not by gamma delta T cells.

We induced a virus-specific cytotoxic T lymphocyte (CTL) response in B2 chickens by i.v. inoculation with 100 TCID50 of the reticuloendotheliosis virus (REV). Chickens were sacrificed 7 days after the infection and cytotoxic activity of the spleen cells against various target cells was assayed in a 4 h 51Cr-release assay at an effector to target ratio of 100:1. In addition, T cell receptor (TCR) alpha beta and TCR gamma delta cells were negatively selected from the REV-immune spleen cells and used as effector cells against REV-infected B2 target cells. (On average 40% of spleen T cells express TCR gamma delta in the chicken.) By inhibition of the cytotoxic activity of the immune spleen cells against REV-infected syngeneic target cells with monoclonal antibodies specific for chicken CD3 and CD8 molecules, the effector cells could be identified as CD8+ T cells. The cytotoxic activity was MHC-restricted, as only syngeneic but not allogeneic REV-infected target cells were lysed by REV-immune spleen cells, and virus-specific, as no cytotoxic activity could be found using uninfected syngeneic target cells. When assaying the activity of the negatively selected, > 98% pure alpha beta and gamma delta T cells, it was found that alpha beta T cells exerted virus-specific CTL activity ranging from 26 to 62% specific 51Cr-release, while gamma delta T cells showed only 2-4% 51Cr-release. These data indicate that REV-specific CTL response is mediated by alpha beta T cells and that gamma delta T cells are not involved in virus-specific CTL activity in the spleen of REV-infected chickens.


Complex pattern of the myelo-monocytic differentiation antigens MRP8 and MRP14 during chronic airway inflammation.

One of the characteristics of cystic fibrosis is the presence of the so-called cystic fibrosis antigen in the plasma of patients. The CF-antigen has been shown to consist of the two calcium-binding proteins MRP8 and MRP14. In the present study we investigate first whether elevated plasma titers of MRP8 and MRP14 are linked to the primary defect of CF or are rather a result of chronic airway inflammation; and second, whether the known complexes of these proteins may have in vivo relevance during inflammation. By employing the ELISA technique we measured MRP8 and MRP14 levels in the plasma of patients suffering from CF or nonspecific chronic bronchitis (CB) and of healthy controls, in sputum of CF and CB patients, and in saliva of CF patients and healthy controls, respectively. We found elevated plasma concentrations of both proteins in CF and CB patients compared to healthy controls. Levels correlated significantly with systemic and local signs of disease activity (i.e. c-reactive protein (CRP), daily sputum production). MRP8 and MRP14 both were found in high amounts at similar concentrations in sputum of CF and CB patients and, to a lesser extent, in saliva of CF patients and healthy donors. After covalent cross-linking at least three different complexes composed of MRP8 and MRP14 with approximate molecular weights of about 25, 35 and 48 kDa were detected in all samples. From this we conclude that the elevated plasma levels of MRP8 and MRP14 in CF and CB are the result of inflammatory processes. Further, possible biological functions of these proteins seem to be associated with complexed forms of MRP8 and MRP14 rather than with individual proteins.


Self-reactive and antigen-specific T cell clones derived from a HLA-DR4+/DR5+ donor: T cell receptors and MHC-restriction patterns.

The relationship of heat shock proteins and rheumatoid arthritis as well as the relevance of autoreactivity in this disease is unclear. T cells of six individuals (four expressing the DRB1*0401 allele, one harboring DRB1*0404 and one the DRB1*0407 allele) were cloned in the presence of 65kD mycobacterial heat shock protein (HSP60) in order to determine T cell receptors (TcR) used and the MHC class II restriction patterns of potentially relevant T cell clones (TcC). All TcC obtained were not specific for HSP60, but six TcC of one donor (HLA-DR4/HLA-DR5) were responsive towards autologous antigen-presenting cells. One TcC displayed authentic autoreactivity whereas five TcC reacted specifically to serum proteins. The amino acids (aa) of the MHC molecule, crucial for immune recognition were mapped to aa #71 or #86 of either maternal or paternal origin. The strictly autoreactive TcC did not recognize transfected L cells implicating specificity for self-peptides not presented by L cells or the involvement of adhesion molecules. Correlations between autoreactivity and TcR V(D)J sequences or N nucleotides of various "autoreactive" TcC were not evident.


Diagnostics and categories of patients.

Care in identifying and categorizing patients is a critical first step in proper drug evaluation. The appropriate diagnostic tests include culture and urinalysis. They are essential for the firm establishment of a diagnosis and should be sensitive and specific enough to meet the appropriate clinical requirements. The clinical categories outlined are encountered in clinical practice with a frequency that is sufficient to provide enough patients for an assessment of the response to antimicrobial therapy and to give information that will have practical value for clinicians.


Inclusion criteria for acute uncomplicated cystitis.

Inclusion criteria for acute uncomplicated cystitis were studied in a total of 307 patients. The data on recurrence should be grouped according to age or menopause, because recurrence was observed only in postmenopausal patients, and the mean age was significantly higher in the recurrence group than in the non-recurrence group. Bacteriuria of 10(3) and 10(4) cfu/ml could be included only when urine was collected by catheterization or very careful clean-catch method, because the incidence of uropathogens was significantly low even in patients with bacteriuria of 10(4) cfu/ml, when urine was collected by conventional midstream catch.


Criteria for the diagnosis of urinary tract infection and for the assessment of therapeutic effectiveness.

Three parameters--urinary symptoms, pyuria, and bacteriuria--can be used independently or in combination to define the presence of urinary tract infection. Using these parameters, several approaches to defining urinary infection in various clinical contexts are discussed. Similarly, approaches to the definition and classification of therapeutic outcomes after antimicrobial treatment are explored. Further research is needed to more precisely evaluate the effectiveness of various criteria for diagnosis and cure of urinary infection.


The dipstick test in the diagnosis of UTI and the effect of pretreatment catheter exchange in catheter-associated UTI.

We examined the value of the dipstick test for detecting pyuria and bacteriuria in the diagnosis of urinary tract infection (UTI). The dipstick esterase test could be quickly assessed and could easily detect leukocyte esterase in the urine. This was well correlated with the conventional sedimentation method. The dipstick nitrate reduction method for detecting bacteriuria, however, was not well correlated with the urine culture method. These findings suggested that the dipstick esterase test was a useful method for detecting pyuria in the diagnosis of UTI, but not the dipstick nitrate reduction method. Catheter-associated UTI is the most difficult category of UTI to treat and control. One of the reasons for this is the formation of biofilm around the indwelling catheter. We attempted to evaluate the effect of catheter exchange just before treatment of catheter-associated UTI with either 300 or 600 mg/day of levofloxacin, one of the newer quinolones. However, we are unable to find any apparent effect on the drug's efficacy.


Standards of therapy for urinary tract infections in adults.

Therapeutic standards have not been well defined for many forms of bacterial urinary tract infection. In women with uncomplicated infections, these exist for bacterial cystitis and for acute pyelonephritis. For most other categories of illness, among patients with complicated infections, no treatment regimens have been determined. As a result, well-designed clinical trials for these patient populations should be a priority.


French consensus on antibiotherapy of urinary tract infections. The French Society for Infectious Diseases.

We report on a recent French Consensus Conference on antimicrobial therapy of urinary tract infections (UTI). These guidelines were limited to questions on which a consensus seemed possible, namely lower uncomplicated urinary tract infections, bacteriuria in pregnancy and in the elderly, acute pyelonephritis and prostatitis.


Design of clinical trials in patients with urinary tract infections.

This overview deals with the optimization of the design of clinical trials in patients with urinary tract infections (UTIs). Despite the fact that UTI is one of the most common types of infection and that the main end-point (elimination or persistence of bacteriuria) is objective and easy to register, the quality of studies performed and published has generally been less than optimal. Problems that should always be addressed in the study protocol are definitions of terms used, for example bacteriuria, level of the infection (cystitis or pyelonephritis), and uncomplicated and complicated infections; dimension of the patient's sample to allow adequate testing of a null hypothesis; procedures before, during and after treatment; methods for analysis of the results.


Prophylaxis: recurrent urinary tract infection in women.

Long-term, low-dose antimicrobial prophylaxis is effective for the prevention of acute uncomplicated urinary tract infection in women. Selected new antimicrobials should be assessed to determine their efficacy for this clinical use. Recommended guidelines for future studies of prophylactic therapy need to address several issues. The study population must be limited to women with recurrent symptomatic uncomplicated urinary tract infection. Antimicrobials studied should be excreted in the urine, with an in vitro spectrum that includes the common uropathogens. An extended half-life may be beneficial. Monitoring during the study should include monthly urine cultures and vaginal, periurethral and rectal colonization studies. The primary outcome measurement is symptomatic urinary tract infection. Secondary outcomes would include asymptomatic bacteriuria, adverse antimicrobial effects, colonization with potential uropathogens, and development of resistance. The comparative regimen should be one of the current standard regimens, trimethoprim/sulphamethoxazole, nitrofurantoin, or trimethoprim.


Prophylaxis in urological surgery.

Prophylaxis in urological surgery is usually taken to mean antibacterial agents. However, in this study, other factors such as the environment, patient risk and surgical risk factors are also taken into account. Because patients have a wide variety of possible risk factors, individual variations must be possible. In standard transurethral resection in non-risk patients, single-dose preoperative prophylaxis may be sufficient. In open surgery prophylactic measures should be varied according to the extent of the procedure.


Prophylactic antibiotherapy in urological surgery.

The aim of prophylactic antibiotic therapy in urological surgery is the prevention of local or systemic infections. The authors treated 100 patients prophylactically; 62 were treated with amikacin and 38 with cefotaxime. Of the 62 patients treated with amikacin, 18 had infectious complications. Of the 38 patients treated with cefotaxime, ten had infectious complications. We conclude that in the Hospital do Desterro the incidence of infectious complications is high, despite antibiotic prophylaxis.


Prostatitis--diagnostic criteria, classification of patients and recommendations for therapeutic trials.

Infections of the prostate may occur despite the numerous host defences of the male urogenital tract. It is important to distinguish patients with genuine inflammation of the gland from the larger number of men with symptoms but no signs of an inflammatory response (prostatodynia). To define prostatitis, the degree of the inflammatory reaction must first be determined. Increased numbers of leucocytes in expressed prostatic secrections (EPS) are essential for this diagnosis. Careful lower urinary tract studies may then be used to classify the patients into two major groups of bacterial and nonbacterial prostatitis. Chronic bacterial prostatitis is primarily due to Escherichia coli. Gram-positive prostatitis is debatable. In chronic bacterial prostatitis, secretory dysfunction is common. The increased alkalinity of the pH of expressed prostatic secretions is one of the reasons for poor results of antibiotic therapy. Uncommon microorganisms, such as Chlamydia trachomatis and Ureaplasma urealyticum may be involved in some cases of the "nonbacterial" form. Routine culture for these microorganisms is not recommended.


Detection of a local prostatic immune response to bacterial prostatitis.

Bacteria-specific antibody responses in expressed prostatic secretions (EPS) were investigated by use of an indirect immunoperoxidase method. Positive responses were observed in all 12 patients with acute bacterial prostatis due to gram-negative rods. However, in 41 patients with chromic prostatitis, antibody responses varied depending on the bacterial species; no positive responses were observed in cases resulting from gram-positive cocci.


Effect of vitamin E therapy on sexual functions of uremic patients in hemodialysis.

Twenty-four uremic patients on hemodialysis who had never been treated with vitamin E or related drugs and 12 control patients with normal renal function were studied. Hemodialysis patients were randomly divided into two groups; 12 were treated with oral vitamin E (300 mg/day) for eight weeks and 12 uremic patients and 12 controls were given placebo. Serum vitamin E, prolactin, FSH, LH, and free testosterone levels were measured in all patients before and after treatment. After the vitamin E treatment serum prolactin levels were significantly decreased (50.8 vs 15.4 ng/ml, p < 0.01). Vitamin E levels were significantly increased (1.11 vs 1.22 mg/dl, p < 0.05). Serum FSH, LH and free testosterone were not affected. In the other two groups there were no significant changes. These results show that vitamin E treatment lowers prolactin levels in uremic hemodialysis patients. This might be due to inhibition of central prolactin secretion. Vitamin E inhibits pituitary gland hypertrophy in vitamin E-deficient rats.


Variables associated with the assessment of systemic tumor necrosis factor alpha levels during hemodialysis.

Conflicting results have been published concerning the systemic induction of the cytokine tumor necrosis factor alpha (TNF alpha) during hemodialysis (HD). We therefore evaluated in vitro TNF alpha production in whole blood as well as in vivo variability of TNF alpha levels in patients on long-term HD. Whole blood was incubated at room temperature (RT) with or without exogenously added endotoxin (ET), and plasma-TNF alpha was measured after 5, 30, 120, 240, and 960 min by specific enzyme immunoassay. Additionally, plasma-TNF alpha before and after 120 and 240 min HD was studied longitudinally once a week over a period of 4 weeks in 36 patients on Cuprophan (CU, n = 23) or polysulfone-F60 (PSu, n = 13) HD. Mean plasma TNF alpha levels in vitro rose from (mean) 8 pg/ml after 5 min to 12 pg/ml (120') and 32 pg/ml (960') even without ET addition, and to 18 pg/ml (after 120') and 88 pg/ml (after 960') when 0.1 microgram/ml ET were added. Pre-dialytic as well as intra-dialytic TNF alpha levels in patients showed high intra-individual variability. A substantial (> 100%) increase in plasma TNF alpha was observed during only 14 out of 84 treatments with CU and 20 out of 47 with PSu, however, the increase in TNF alpha was not statistically significant in either group. We conclude that the sampling procedure, if not carefully standardized, is a potential source of artifacts with regard to "systemic" TNF alpha levels. The high intra and inter-individual variability of plasma TNF alpha suggests that results of cross-sectional studies are questionable.


Peritoneal dialysis using conventional, lactate--containing solution sterilized by ultrafiltration.

Peritoneal dialysis was performed on 7 end-stage renal failure patients using an I-lactate-containing solution sterilized by ultrafiltration through polyamide filters. The patients tolerated the procedure well while their metabolic acidosis and azotemia improved.


Neutrophilic intracellular acidosis induced by conventional, lactate-containing peritoneal dialysis solutions.

Exposure of human neutrophils to a conventional, acidic, lactate-containing peritoneal dialysis solution (PDS) resulted in the development of a prompt and substantial intracellular acidosis. It is possible that this intracellular acidosis contributes to cellular dysfunction.


Perforation of the superior vena cava by a subclavian hemodialysis catheter: early detection by angiography.

A dual-lumen subclavian catheter was placed for temporary dialysis access in a 36-year-old woman. Clinical suspicion for a possible vena caval perforation by the catheter tip was confirmed by injection of contrast through the catheter. This technique allowed rapid diagnosis and prevented further potential complications related to catheter malposition.


High volume plasma exchange in fulminant hepatic failure.

We investigated the effect of repeated high volume plasma exchange with fresh donor plasma in 11 patients with fulminant hepatic failure, all initially in stage 3 or 4 encephalopathy. A daily exchange of a volume equal to the extracellular volume (20% of body weight) on three consecutive days was intended. We obtained an average of 2.6 exchanges each with a mean volume equal to 16% of the body weight. Five patients (46%, 95% confidence limits 17%-77%) survived, all with acetaminophen induced liver failure. Four of the 6 non-survivors showed a temporary improvement in cerebral function. Two of the patients woke up completely. The 6 non-survivors maintained a stable condition with a systolic blood pressure > 110 mm Hg for a mean of 6.9 days after initiating plasma exchange. Plasma exchange may be considered in acute liver failure in patients with residual liver function before transplantation is finally decided. In addition, plasmapheresis may be used to keep patients with definite liver failure clinically stable until a transplant can be performed.


Hemoperfusion with a new anion exchange resin corrects the metabolic alkalosis in pyloric stenosis: an experimental demonstration.

An experimental model of hypertrophic pyloric stenosis was made by suture of the pyloric wall and gastrostomy in 10 rabbits under general anesthesia. Blood sampling indicated severe alkalosis and hypochloremia 3h 30 min after surgery. To correct the derangement, we tested an ion exchange resin (Dowex SAR), coated with a methacrylic hydrogel. A cartridge containing 18 g of this resin was inserted in an extracorporeal circuit. This chloride charged resin achieved uptake of HCO3- ions, and elution of Cl- ions. The electrolytic balance was fully restored after 10 min of treatment.


In vitro hemolysis by mechanical heart valve prostheses with tilting disc.

Hemolytic and subhemolytic blood damage by mechanical heart valve prostheses have been observed in both clinical and in vitro investigations. A direct comparison between these studies is not possible. Nevertheless the transfer of some in vitro results to the behaviour of the valve in situ may be performed considering the similarity principle. This requires the use of dimensionless similarity numbers such as the plasma's hemoglobin concentration (PHb) or others, instead of dimensioned parameters. To evaluate the in vitro hemolysis of valve prosthesis a test chamber filled with human banked blood was used. An artificial ventricle ensuring an oscillatory flow through the valve was also used. The rise of PHb was evaluated in terms of a similarity number, called the lysis number. This number describes the probability of destroying a single red blood cell participating once in the hemolytic process under consideration. The lysis number, a Björk-Shiley valve (TAD 29), was found to be in the order of 2 x 10(-4). From this, the survival time of erythrocytes in patients with an artificial heart valve was estimated. It was found to be in the order of 20 d of T50 Cr in agreement with clinical results.


Liquid phase enzyme reactor, a new bioreactor principle.

One of the drawbacks of solid phase enzyme reactors is the sharp decrease in substrate affinity as shown by an increase in the Km app value. To circumvent this problem a liquid phase enzyme reactor system was designed. Biotin labeled L-Tryptophan side chain oxidase (TSO) was directly injected into the plasma circuit of a filter plasmaphoresis system of rabbits and adsorbed onto an Avidin column prior to its reentry into the animal's general blood circulation. In five experiments total L-Tryptophan depletion could be observed in the plasma circuit during 60 minutes of the experiment with complete readsorption of the enzyme to the Avidin column.


William Harvey, Peter Lauremberg and cardiac output.

In 1636, the Rostock professor of medicine and the art of poetry, Peter Lauremberg (1585-1639), was one of the earliest to mention circulation which had been discovered by William Harvey and documented in his anatomical manual. In 1628 William Harvey proved the existence of the blood circulation by calculating the "cardiac output in a half an hour (semihora)". The answer to the question why Harvey chose half an hour as the time range can be found in the way of measuring time usual at that period. The sandglasses were turned half-hourly in maritime navigation and the wheel-clocks on shore had only the hour-hand. Improved chronometry was one of the prerequisites for measuring cardiac output. The minute-hand became usual after 1700 and the second-hand later on. Taking into consideration the alterations of cardiac output made the latter one of the most important circulation parameters in diagnostics, prognostication and therapeutics.


Clinical pharmacology and pharmacoepidemiology: synergistic interactions.

There are many opportunities for synergistic interactions between clinical pharmacology and pharmacoepidemiology. They range from the applications of molecular biology and pharmacogenetics to population studies, and vice versa, to population pharmacokinetics, to the evolution of well-designed, large scale clinical trials in less contrived settings. Ultimately, the synergy can contribute to intelligent and hopefully more efficient drug development, and when a drug goes to market, a better understanding of what will happen.


Interneuronal information transfer: recent advances in synaptology.

The elementary mechanisms underlying synaptic transmission are described with respect to the following topics: 1. morphology and bioelectric activity of nerve cells; 2. electrical and chemical synapses; 3. transmitter-operated opening of membrane channels on the basis of allosteric effects; 4. synaptic transmission on the basis of second messengers (adenylate-cyclase-system, phosphoinositol-cycle); 5. interactions of transmitters.


Relation between psychometric tests and quantitative topographic EEG in pharmacology.

Both, psychometric tests and quantitative pharmaco-EEG are accepted as necessary tools in different fields of pharmacology. But using these methods separately, none is able to forward informations about the behavioral performance and the central nervous demand simultaneously. The solution of this problem is a complex psychophysiological set-up. Till today such complex measurement set-ups are a rarity. The main reason is the impossibility of EEG recordings during psychometric tests without different artefacts. In the present paper we demonstrate by using our own CATEEM-System in connection with the IBIS-Psychometry-system the possibility to get artefact free EEG recordings during psychometric test conditions. The different mental loads at different tests are producing a graduated increase in the delta and theta frequency range of the EEG of the fronto-temporal region and the occipital region of the cortex. During the tests a decrease of alpha-activity is seen generally. These effects can be described quantitatively as the topographical distribution of frequency changes. The present data are in line with the knowledge about the functional and anatomical structure of the human brain.


Identification and treatment of postmenopausal women at risk for the development of osteoporosis.

One in the three women develops osteoporosis--low bone mass and structural deterioration leading to fractures. Pre- and postmenopausal deficiency states are main causes. Estrogens prevent bone loss: Oral doses of 2 mg estradiol or 0.625 conjugated estrogens/day or 50-100 micrograms transdermal estradiol/day substantially reduce vertebral, forearm, and hip fractures. Certain progestins may enhance this effect. Calcium as a prerequisite for attainment of peak bone mass will not substitute for estrogen replacement. Selection of patients actually being at risk for postmenopausal osteoporosis needs to be improved substantially; there is no sensitive single test or testing system for osteoporosis. As individual history and physical exam or biochemical markers of bone resorption and formation rarely provide the early diagnosis of osteoporosis, prophylactic estrogen replacement therapy has to be considered in the majority of postmenopausal women to achieve prevention of postmenopausal osteoporosis. Compliance of replacement therapy in the European countries is poor, only 5-25% of postmenopausal women use estrogen replacement therapy for more than one year. Major compliance problems are alleged weight gain, resumption of withdrawal bleeding and fear to develop breast or endometrial cancer.


Drug utilization research in primary health care as exemplified by physicians' quality assessment groups.

Drugs in primary health care are often prescribed for nonrational reasons. Drug utilization research investigates the prescription of drugs with an eye to medical, social and economic causes and consequences of the prescribed drug's utilization. The results of this research show distinct differences in drug utilization in different age groups and between men and women. Indication and dosage appear irrational from a textbook point of view. This indicates nonpharmacological causes of drug utilization. To advice successfully changes for the better quality assessment groups of primary health care physicians get information about their established behavior by analysis of their prescriptions. The discussion and the comparisons in the group allow them to recognize their irrational prescribing and the social, psychological and economic reasons behind it. Guidelines for treatment are worked out which take into account the primary health care physician's situation. After a year with 6 meetings of the quality assessment groups the education process is evaluated by another drug utilization analysis on the basis of the physicians prescription. The evaluation shows a remarkable improvement of quality and cost effectiveness of the drug therapy of the participating physicians.


Drug use in pregnancy: east German data of an international collaborative study.

In an epidemiological collaborative international study under the auspices of WHO-Euro the drug use in pregnancy was investigated in 22 countries in 14,778 women and in hospitals of three different levels. The East German state Thuringia took part according to the annual birth rate with 300 women in 3 hospitals (Jena, Gera, Greiz). In the international average, 14% of the enrolled women took no drugs during pregnancy before admission to hospital for delivery. In East Germany 44% of the women taking part in the study had no drug administration during pregnancy. The critical use of iron preparations and vitamins there has to be mentioned. Under delivery, 99% of the Thuringian women received drugs. In the puerperium the administration of ergot derivatives and of laxatives exceeds the international average and has to be critically revised, but the administration of antiinfectives in only 1/5 and of analgetics 1/3 of the international average.


Problems in performing a double-blind multicenter study using a hypnotic in private practice.

1. The procedure described--the immediate data transfer and entry system (ITES)--is suitable to improve the quality of data collected in multicentre studies in private practice. 2. The results of the study show that regarding influence on sleep quality and daytime well-being the non-benzodiazepine Z is significantly superior to placebo and slightly superior to the benzodiazepines F and T. 3. The advantage of Z treatment is the better daytime well-being after taking the hypnotic for sleep induction the night before. 4. This study shows that a quality standard equal to that in clinical practice may be achieved in private practice.


Bioequivalence of a new atenolol formulation.

A new generic drug of atenolol, Atenolol (A), (Fahlberg-List Magdeburg, Germany) was studied in comparison with standard preparation (S) in their pharmacokinetic behaviour in 12 patients under steady state conditions. The concentration-time-profile of both preparations was nearly identical. The half time of elimination was calculated for A at 6.5 h and for S at 5.9 h. From the ratio of AUC from A to S (extent of absorption) a mean bioequivalence of 103.1% (90%-confidence limits 0.85-1.21) was estimated. Corresponding values for the rate of absorption were in the mean 102.8% (90%-confidence limits 0.94-1.12).


Pharmacokinetics of trapidil (Rocornal) in patients with chronic liver disease.

The pharmacokinetics of trapidil (Rocornal, Deutsches Hydrierwerk Rodleben GmbH) were studied in 15 patients with chronic liver disease (12 patients with hepatic cirrhosis, 2 patients with alcoholic fatty liver, one patient with liver fibrosis). Trapidil was given orally (200 mg, Rocornal dragees 100 mg) as well as intravenously (100 mg) in random order. Serum samples were analyzed for trapidil by HPLC. The pharmacokinetic parameters were compared with the parameters of 12 healthy volunteers, investigated by Weiss [1991]. Total plasma clearance was decreased significantly in patients with hepatic cirrhosis (99.6 ml/min vs 273.1 ml/min in controls and 255.3 ml/min in patients with non cirrhotic liver disease). However, there was no difference in clearance between patients with compensated and patients with decompensated cirrhosis. Clearance and aspartate aminotransferase activity correlated inversely. In addition, in some of the patients suffering from portal hypertension delayed absorption was observed, but the difference did not reach statistical significance. The volumes of distribution were significantly lower in patients with non alcoholic cirrhosis (19.9 l vs 36.8 l in controls and 41.0 l in patients with alcoholic cirrhosis). It might be concluded from this study, that dosage adjustments are necessary in treatment of patients with cirrhosis. In patients suffering from portal hypertension an intravenous administration should be prefered.


Investigation of the variability of etoposide pharmacokinetics in children.

The interindividual variation of etoposide pharmacokinetics under different therapeutic schedules and the rationale of dose reduction in young children and newborns were investigated in the present study. We evaluated pharmacokinetic parameters during short-term infusion in 21 therapy cycles (18 children) on different therapeutic schedules (66-200 mg/m2). In 33 patients state levels (Css) during continuous infusion of 125 mg/m2/96 h were analyzed by an HPLC-method. During short-term infusion half-life (3.3 +/- 0.7 h) and total body clearance (26 +/- 6 ml/min/m2) showed a relatively narrow range. Calculation of the area under the curve was standardized to a dosage of 100 mg/m2 (AUC/[100 mg/m2]). The AUC then was 68 +/- 17 (micrograms.h/ml)/(100 mg/m2) with a coefficient of variation of 25%. In the subgroup of 10 patients who received 150 mg/m2 the AUC was 106 +/- 15 micrograms.h/ml with only 14% coefficient of variation. In children < 2 years, pharmacokinetic parameters were within the normal range. Calculation of the doses the short-term infusion per kg resulted in a dose reduction or 31% (mean, n = 5) and in 22% (mean) lower AUC's. With continuous infusion of 125 mg/m2 etoposide the interpatient variability was greater with a 33% coefficient of variation of the Css (4.4 +/- 1.4 micrograms/ml; n = 24). Calculation of the doses per kg (age < 1 year) or 2/3.kg resulted in reduced Css. Standardization of these levels showed Css (125 mg/m2) of 4.6 +/- 1.4 micrograms/ml and a coefficient of variation of 31%. Interpatient variability of etoposide pharmacokinetics at least during short-term infusion is limited. Dose reduction is not substantiated in children < 2 years by our pharmacokinetic data.


The biliary and renal elimination of the new muscarinic-1-antagonist AWD 26-06 in volunteers with T-tube after cholecystectomy.

The biliary and renal elimination of the new muscarinic-1-antagonist AWD 26-06 were investigated in 6 female volunteers (age: 26-69 years) 9-14 days after cholecystectomy and T-tube construction. After a single oral dose of 50 mg AWD 26-06 as an aqueous solution the amount of the unchanged substance was determined in serum, T-tube bile and urine with a special HPLC-method. The concentration maximum was reached earlier and higher in bile (60 +/- 22 min; 10.8 +/- 5.7 micrograms/ml) than in serum (73 +/- 28 min; 0.98 +/- 0.53 micrograms/ml). During the whole observation time of 24 h the AWD 26-06 concentration in bile was 2-21-fold higher than in serum. In mean 2.3 +/- 1.5% of the administered dose were eliminated unchanged by bile and 12.2 +/- 5.9% by urine. More than 70% of the dose were metabolized. The results gave a hint at active liver transport processes and an enterohepatic recirculation. A drug interaction was observed with valproic acid on the metabolic level. The great interindividual variability of pharmacokinetic data can be caused by the heterogeneity of the subject group and a genetic polymorphism in the metabolism of AWD 26-06. The bile sampling by means of a T-tube is a simple but effective method under consideration of special conditions.


HPLC-methods for determination of lipoic acid and its reduced form in human plasma.

A method has been developed for the HPLC analysis of lipoic acid and its reduced form (dihydrolipoic acid) in biological samples. Both substances are released from the samples by enzymatic hydrolysis and extracted by solid phase column. The extracts, after evaporation, were chromatographed and quantified by electrochemical detection. The basic level was in the range 1-25 ng/ml for lipoic acid and 33-145 ng/ml for dihydrolipoic acid (6 healthy volunteers).


Investigations into a new antiarrhythmic substance Z-2-amino-5-chlor-benzophenon-amidin-hydralazin in humans.

Z-2-amino-5-chlor-benzophenon-amidin-hydralazin is a new chemical potential antiarrhythmic substance. The blood levels were investigated after different dosages and forms of administration in patients and volunteers. The determination of the substance can be performed by high-pressure liquid chromatography. In addition the pharmacokinetic parameters were calculated. The pharmacokinetic profile is similar in humans and animals.


Modelling of the pharmacodynamics and pharmacodynamic interactions of CNS active drugs.

The pharmacodynamics and pharmacodynamic interactions of benzodiazepines have been determined using amplitudes in the 12-30 Hz frequency band of the EEG as a measure of the pharmacological response. Following the administration of a single intravenous dose, plasma concentration and pharmacological effect versus time profiles were determined and subjected to simultaneous pharmacokinetic-pharmacodynamic modelling to derive individual concentration EEG effect relationships. For flunitrazepam, midazolam, oxazepam and clobazam the concentration EEG effect relationships could be characterized on basis of the sigmoid Emax model. The values of the EC50 differed widely. A close correlation between the value of the EC50 and the affinity to the nanomolar benzodiazepine receptor in vitro was observed. For midazolam, bretazenil, flumazenil and Ro 19-4603 in addition to differences in potency also widely different values of the Emax were observed, which are in agreement with the known pharmacological properties of these compounds. The pharmacodynamic interaction between midazolam and flumazenil was characterized both under steady-state and non steady-state conditions. It was found that the effects of combined treatment with these drugs can be described and predicted on the basis of a competitive interaction model. The findings of these studies demonstrate that on the basis of an integrated pharmacokinetic-pharmacodynamic approach, important information on the pharmacodynamics and pharmacodynamic interactions of CNS active drugs can be obtained.


Population pharmacokinetics.

Traditionally pharmacokinetic studies have been performed in small homogenous groups of subjects, often normal healthy, young male volunteers. These studies are well controlled and generate meaningful baseline data. However, concern has been expressed that insufficient data is collected at an early state in the target population during a drug's development. Logistically studies during Phase III are difficult, control is lacking and what data that is generated is very sparse. In recent years there has been a growing interest in techniques capable of analyzing sparse data and there is now pressure on manufacturers to obtain more kinetic and dynamic information from Phase III studies. The issues, problems and the current status of population based studies will be discussed.


The importance of prospective planning of pharmacokinetic trials. Considerations of studies on the phenytoin-digoxin-(P-D) and phenytoin-digitoxin-(P-DT) interaction.

To study possible pharmacokinetic interactions between two compounds a single-dose or a multiple dose experimental design may be used. Two prospective trials on the possible pharmacokinetic interaction between phenytoin (P) and digoxin (D) or digitoxin (DT) were performed in healthy volunteers. It is demonstrated that an statistically significant pharmacokinetic interaction was found only after multiple dosing under conditions of steady-state, whereas after single dosing no interaction was observed. In case of investigating possible pharmacokinetic interactions a multiple dosing trial design appears to be advantageous.


Planning of drug interaction studies involving digoxin treatment: a statistical view.

The most valuable information we obtained from literature research was, that digoxin serum concentrations are generally of primary interest rather than area under curve or maximum concentration. Steady-state plasma levels appeared as a generally accepted endpoint to judge pharmacokinetic interaction. However, time-points for measurements were chosen differently and varied widely. Often, digoxin clearance was also considered. Despite the large amount of data, publications, opinions and single conclusions, no general statement could be made either about what is considered a relevant interaction or what is judged as "no interaction".


Observations on color vision testing in ocular hypertension and glaucoma.

Forty-eight patients aged from 60 to 69 years (58 eyes) with ocular hypertension (OHT) or primary open angle glaucoma (POAG) and a control group of 16 persons (31 eyes) were studied with six color vision tests: Standard Pseudoisochromatic Plates Part 2, Farnsworth Panel D 15, Farnsworth-Munsell 100-hue (FM 100) test, Lanthony Desaturated Panel, Nagel (red-green) anomaloscope, and Besançon (blue) anomalometer. In the color vision tests, the newly diagnosed OHT eyes without treatment differed significantly from the control group in the blue anomalometer. The long-term OHT eyes with treatment had no significant difference from the normals in any of the tests. The newly diagnosed POAG eyes without treatment were significantly different from the normals in the FM 100 test as well as in the boxes I, II, III and IV of the test, in the Lanthony Desaturated Panel and in the blue anomalometer. The long-term POAG eyes with treatment only differed significantly from the normal eyes in the blue anomalometer. The box IV of the FM 100 test and blue anomalometer were observed to be the most useful of these six tests in finding the possible early beginning of the blue color vision defect in the group of newly diagnosed OHT.


Color vision in Stargardt's disease.

The color vision of nine patients aged from 13 to 52 years with Stargardt's disease was studied with the following tests: Standard Pseudoisochromatic Plates part 2 (SSP2), Farnsworth-Munsell 100 hue test (FM100), Nagel (red-green) anomaloscope and Besançon (blue) anomalometer. At the beginning of the disease, a very slight defect in red-green color vision could be demonstrated. Later, a distinct acquired red (pseudo-protanomalous) defect in the Nagel anomaloscope and an abnormal error score in the FM100 test were observed. In advanced stages, the red defect became stronger (scotopization) and the FM100 test showed a red-green axis. In the course of the disease, a blue defect with the SPP2 plates and with the Besançon anomalometer could also be found. The visual acuities of the patients had a significant correlation with the matching ranges of the Rayleigh equation and the Moreland equation. The duration of the disease did not show any correlation with the color vision tests.


Diabetic retinopathy in a population of 1,302 insulin dependent diabetics (IDDM) diagnosed before 30 years of age.

The authors analyse the data resulting from the first ophthalmological observation of 1,302 insulin dependent diabetics whose age at diagnosis is less than 30 years and who have been observed regularly by the Portuguese Diabetic Association. The prevalence of retinopathy is 41, 6%; 34.3% is non-proliferative and 7.3% is proliferative. Retinopathy is more frequent in males (P < 0.001). The prevalence of retinopathy increases with the duration of diabetes and it is equal to or greater than 80% in people who have had diabetes for 10 years or more. 'Poor' glucose control, the coexistence of other late complications and arterial hypertension increase the risk of retinopathy (P < 0.001).


Internal choroidectomy of posterior uveal melanomas under a retinal flap.

Local excision of uveal melanoma is an intriguing therapeutic modality in selected cases. An internal choroidectomy under a retinal flap has been developed as an alternative to retinochoroidectomy in managing posterior pole melanomas. This technique offers more adequate preservation of retinal architecture, thus potentially enhancing central visual function in patients with tumors located close to the fovea.


Impression Cytology with Transfer in xerophthalmia and conjunctival diseases.

During a countrywide survey, we assessed the prevalence of clinical signs of xerophthalmia and of major conjunctival diseases in a randomized sample of 2,445 subjects representative of the population of the Republic of Djibouti. On a part of this sample, conjunctival Impression Cytology with Transfer (ICT) test and a plasma retinol determination were performed. Xerophthalmia as a public health problem was displayed by clinical signs (Bitot's spots, corneal scars among preschool children), low plasma retinol levels and ICT test results: 9.3% with deficient cytology in the rural area and 12.3% in the urban one (age-standardized rates). Results of ICT were related to age (p < 0.00001). Vitamin A deficiency was prevalent not only in preschool children but also up to 15 years. Moreover, ICT results are influenced by conjunctival diseases: compared to age-matched controls, there were more abnormal cytologies among patients with trachomatous inflammation (p = 0.025), conjunctivitis (p = 0.024) or Limbal Vernal Keratoconjunctivitis (p = 0.015). Thus ICT shouldn't be performed among children with conjunctival diseases. In the region under study conjunctival diseases had high rates of prevalence: 16.4% of trachomatous scarrings in the urban area (standardized rate), 8% of conjunctivitis among rural preschool children, and 5% of Limbal Vernal Keratoconjunctivitis among children between 5 and 14 years in both areas.


Best's multiple vitelliform degeneration.

Best's disease with multifocal lesions is rare. The authors describe four cases of multifocal vitelliform disease. The fluorescein angiographic features of macular and extramacular lesions are considered. Different stages of evolution may be present between central and extramacular lesions.


The follow-up of patients screened for glaucoma with non-mydriatic fundus photography.

In order to evaluate the value of photographic screening in predicting progressive glaucomatous damage, we re-examined 26 subjects 5 years after the initial screening. Of the 26 patients 16 had typical glaucomatous optic disc and visual field abnormalities (n = 7), retinal nerve layer damage (n = 6), or other risk factors of glaucoma (n = 3). In 10 of 26 patients suspected of having glaucoma, no abnormalities were initially confirmed. Of the 16 eyes with initially abnormal findings, 10 (63%) showed progressive changes during the 5-year follow-up period. The 10 initially suspected cases have remained healthy throughout the follow-up, giving a false positive rate of 5.5%. The results of this study indicate that it is possible to identify correctly patients with progressive glaucomatous changes with a non-mydriatic fundus camera.


The Yorkshire Region Children's Tumour Registry--the role of the specialised children's.

The Yorkshire Regional Children's Tumour Registry (YRCTR) has been operating since the early 1980's in Leeds. It has collected registrations of childhood cancer from (approximately) the Yorkshire Regional Health Authority (RHA) area for the years 1974 onwards. All malignant neoplasms, all intracranial tumours, and a number of other disorders diagnosed in persons aged 14 or under, resident in the RHA area are included. For several reasons large general cancer registries are unable to cover childhood malignancies as well as they do adult malignancies. Many of these problems can be addressed by establishing a specialist register. This also has certain advantages for researchers, and can serve as a useful basis for diverse types of research work.


The mapping of natural boron in histological sections of mouse tissues by the use of neutron-capture radiography.

Neutron-capture radiography has been applied to the mapping of natural boron in mouse histological sections. The method is based on the fact that the stable isotope boron-10 has an extremely large cross-section for the thermal-neutron reaction 10B(n, alpha)7Li. The local tissue boron concentrations were evaluated from the corresponding track densities of the nuclear reaction using an equation derived from a theoretical model of the system. The adjustable parameters of this equation were determined in two separate calibration experiments using standardized samples prepared by the addition of known amounts of boron. Interference from other nuclides engaged in nuclear reactions with thermal neutrons was also estimated. In the present experimental conditions the natural boron lower detection limit was 0.03 p.p.m. (fresh weight), and the spatial resolution was of the order of a few micrometers. Boron concentrations in mouse serum and urine were close to 0.22 and 0.57 micrograms ml-1, respectively. In the solid mouse tissues--liver, heart, brain, muscle and spleen--the concentration was usually low, ranging from 0.12 to 0.16 p.p.m. (fresh weight). They were significantly higher in the kidney, especially in the papilla (6.2 p.p.m. fresh weight). Apart from the kidney papilla, where boron was particularly concentrated in wall tubules, the boron distribution in most tissues appeared to be practically homogeneous. Natural boron, and even more so its enriched stable isotope 10B, appear as good candidates for molecular labelling using non-radioactive tracers.


Postnatal changes in sublobular distribution of NADPH-cytochrome P-450 reductase in rat liver.

Immunohistochemical distribution of NADPH-cytochrome P-450 reductase (NADPH-ferrihaemoprotein reductase; EC 1.6.2.4.) in the liver lobule was examined during development of the rat. From the 19th day of gestation to 4 days after birth, the enzyme was distributed uniformly throughout the lobule. The immunostaining for the enzyme was weak before birth, and became slightly stronger after birth. A slightly uneven distribution of immunoreactivity, stronger in perivenular zones, appeared at 5 days after birth. Then, the staining intensity in perivenular zones became progressively stronger with age, except for a slight increase between 10 and 20 days of age. The intensity in periportal zones also increased gradually, although it remained weaker than that in perivenular zones. Around 30 days of age, the distribution of the immunostaining, stronger in perivenular than in periportal zones, was similar to that seen in the lobules of adult animals. Thus, heterogeneity among hepatocytes with respect to the enzyme content is not present in fetal and newborn rats but develops gradually during postnatal development; the postnatal growth of the liver is accompanied by a change in the pattern of the distribution of this enzyme within the lobule.


Noise exposure level while operating electronic arcade games as a leisure time activity.

In order to study noise levels associated with electronic arcade games, noise measurements were made in 3 selected game centers and 192 samples were taken in each location. The background noise was recorded at a level of 61 dB(A) and 64 dB(C). When the electronic games were performed these levels of noise reached to 88 approximately 90 dB(A). The 1/3 octave bands analyzing sound pressure levels showed that more intense noise levels arose in a frequency range between 0.5 and 2.0 kHz. The computed values for noise pollution levels (LNP) and L90 (fast response A-weighted sound level exceeded 90% of the measurement time) ranged from 93.3 to 96.6 and from 85.1 to 87.3 dB(A), respectively. Concerning our results and according to Melnic (1979), it was estimated that these levels of noise might cause 4-8 dB temporary threshold shift (TTS) at 4.0 kHz in an individual with less than one hour of exposure to such a level of noise. As for the employees of the 3 game centers, the 8-hr equivalent continuous sound levels (Leq,8) were in the range of 80.3 approximately 87.5 dB(A), although their exposure time could not be exactly determined. It was suggested that: 1) The maximum levels should be limited to a reasonable level, either by the manufacturers or by the game center owners; 2) Education programs in industry should inform the employees about other factors outside the work that may affect their hearing; and 3) For policy-making on hearing conservation, recreational warning and standards should be established.


Interaction of flufenamic acid on ethanol metabolism in rat.

Flufenamic acid (FA) is a widely used non-steroidal anti-inflammatory drug. It is also known to be an uncoupling agent of oxidative phosphorylation in mitochondria. The interaction of FA and ethanol has been of concern in the occupational health field, since alcohol consumption is a common habit among members of the working population. Thus, we investigated the effects of FA on ethanol metabolism in the rat. In the first experiment, FA and ethanol were administered intragastrically to male Wistar rats. Ethanol and acetaldehyde were measured in blood samples collected from the tail vein by head-space gas chromatography. In the second experiment, the interaction of FA and ethanol was observed in the perfused rat liver. The following items were monitored in perfused livers from both fed and fastd rats: uptake rate of ethanol, production rate of acetaldehyde, level of reduced pyridine nucleotides, and oxygen consumption rate. In the first experiment, the rats with FA showed significantly higher concentrations of both ethanol and acetaldehyde in blood after ethanol intake than the rats without FA. In the perfused liver, FA suppressed ethanol uptake, and increased acetaldehyde concentration in the effluent. FA decreased the level of intracellular reduced pyridine nucleotides which had been elevated by ethanol. FA caused an increase in the oxygen consumption rate, which was not altered by the coexistence of ethanol. It was concluded that FA suppressed ethanol metabolism due to suppression of acetaldehyde oxidation in the liver, despite its uncoupling effect on oxidative phosphorylation in mitochondria.


Dethymicin, a novel immunosuppressant isolated from an Amycolatopsis. Fermentation, isolation, physico-chemical properties and biological activities.

In the course of screening for immunomodulators inhibiting the mixed lymphocyte culture reaction (MLCR), we found a novel immunosuppressant, dethymicin in mycelium of Amycolatopsis mediterranei MI710-51F6. From physico-chemical properties and biological activity it is different from immunosuppressants produced by microorganisms such as cyclosporins, FK506 and rapamycin. It inhibited immune responses in vitro and in vivo, and prolonged skin allograft in rats.


Isolation, purification, synthesis, and antiinvasive/antimetastatic activity of U-77863 and U-77864 from Streptomyces griseoluteus, strain WS6724.

In screening of actinomycetes for structures with differential solid tumor activity, Streptomyces griseoluteus, strain WS6724 was found to produce U-77863 and U-77864. U-77863 exhibited antiinvasive activity in vitro in the membrane invasion culture system (MICS) and a dose-dependent antimetastatic activity in vivo versus K1735-M2 and B16-F10 murine melanomas. The isolation, purification, and synthesis of both structures and biological activity is reported.


Production of new anthracycline antibiotics by microbial 4-O-methylation using a specific daunorubicin-negative mutant.

Microbial 4-O-methylation using a specific daunorubicin-blocked, nonproducing mutant provided the new anthracycline antibiotics 4-O-methylbetaclamycin T, 4-O-methylyellamycin A and 4-O-methyl-13-hydroxyoxaunomycin, from which 4-O-methyloxaunomycin and 4-O-methyl-6-deoxyoxaunomycin were then prepared by further photochemical N-demethylation. Antitumor activities in vitro and in vivo against L1210 cells were compared with those of their 4-O-demethyl derivatives. It was found that all the 4-O-methyl derivatives had a markedly reduced cytotoxicity in vitro as compared with the 4-O-demethyl compounds. However, some of them were endowed with a significantly improved antitumor activity in vivo.


The producer and biological activities of SO-75R1, a new mutactimycin group antibiotic [corrected].

The producer of SO-75R1, a new anthracycline group antibiotic was identified as Nocardia brasiliensis. SO-75R1 was active against Gram-positive bacteria, but not active against Gram-negative bacteria or fungi. All tested Nocardia brasiliensis strains as well as the producer itself were resistant to SO-75R1, although four other pathogenic Nocardia, i.e. N. asteroides, N. nova, N. farcinica and N. otitidiscaviarum were sensitive [corrected].


Pneumocandins from Zalerion arboricola. I. Discovery and isolation.

HPLC bioautography of the directed biosynthesis of Zalerion arboricola led to the discovery of pneumocandin B0 (L-688,786), a new antifungal and anti-Pneumocystis carinii lipopeptide. Isolation techniques were developed to separate this component from pneumocandin A0 (L-671,329) in fermentations of a mutant of Zalerion arboricola. A number of related compounds were also isolated, which differ from pneumocandins A0 and B0 in the hydroxylation patterns on the ornithine, homotyrosine, and proline.


Pneumocandins from Zalerion arboricola. II. Modification of product spectrum by mutation and medium manipulation.

Zalerion arboricola ATCC 20868 produces pneumocandin A0 (L-671,329), a cyclic hexapeptide with a dimethylmyristic acid side chain. This compound has anti-candida and anti-pneumocystis activities. We were interested in looking for other related compounds produced by this organism. To facilitate this search, a simple medium (S2) composed of D-mannitol, peptonized milk, lactic acid, glycine, KH2PO4 and trace elements, which supported the production of a number of such compounds, was designed. For the isolation of mutants, either spores or growing mycelia were treated with N-nitroso-N-methylurethane or N-methyl-N'-nitro-N-nitrosoguanidine and survivors were screened for changes in the product spectrum. From approximately 1,500 survivors tested, 5 mutants were isolated. Mutants ATCC 20957, 74030, 20958 and 20988 exclusively produce various pneumocandins other than A0. These compounds were active against Candida and Pneumocystis carinii. The yield of A0 was found to be increased 2.5-fold over that of the parent in the fifth mutant, MF5415. Further medium studies indicated that the addition of soybean oil to S2 medium improved the yields. Subsequent development of another series of media containing Pharmamedia as a nitrogen source resulted in increase in production by 10- approximately 20-fold. Overall, these studies resulted in substantial improvement in the production of A0 as well as discovery and/or facile production of 7 other related compounds.


Pneumocandins from Zalerion arboricola. III. Structure elucidation.

Pneumocandin B0 (6) and six related lipopeptides are antifungal and anti-Pneumocystis carinii agents from mutants of Zalerion arboricola, whose structures were determined mainly on the basis of spectroscopic analysis. They belong, along with pneumocandin A0 (L-671,329) previously isolated from these laboratories, to the echinocandin class of antifungal agents. The product from base-catalyzed ring opening involving the hemiaminal position of the dihydroxyornithine residue of B0, has been clearly defined as 6b. Modifications were limited to the 3-hydroxy-4-methylproline, 3,4-dihydroxyhomotyrosine and 4,5-dihydroxyornithine residues of pneumocandin A0.