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At least 19 recordsLinked to original sources
PubMed1989

Health-related behavior of people living in a community which experienced a rapid population decrease.

The authors firstly intended to observe the longitudinal effect of rapid decrease and aging of population, which was triggered by the closing of a coal mine in a small island, Takashima (Nagasaki Prefecture, Japan), on the health and behavior of local people. Our initial research objective was, however, re-directed toward practical ways to develop health promotion, because of the increasing expectation of people toward better health.

Attitude to Health↗
PubMed1992

[Effects of oxiracetam on the decrease in population spikes in hypoxic and low glucose media].

Evoked potentials were recorded in rat cerebral cortical slices. The amplitude of the evoked potential was reduced by perfusion with hypoxic (0-25%) or low glucose (0-5 mM) media in a concentration-dependent manner, and the evoked potentials disappeared under severe conditions (below 15% O2, below 3 mM glucose). We investigated the protective effects of oxiracetam on the decrease in evoked potentials under hypoxic (15% O2) and low glucose (3 mM glucose) conditions. Drugs were perfused from 45 min before hypoxic or low glucose perfusion to the end of the experiment. Oxiracetam (10(-6)-10(-5) M) dose-dependently minimized the amplitude reduction of evoked potentials and prolonged their disappearance time. At a concentration of 10(-5) M, oxiracetam protected against the disappearance of evoked potential in 5 of the 6 samples under hypoxic conditions and in all 6 samples under low glucose conditions. Indeloxazine (5 x 10(-6)-10(-5) M) and bifemelane (5 x 10(-6)-10(-5) M) prevented the reduction of the amplitude of evoked potentials under low glucose conditions. However, these drugs had no effect at a concentration of 10(-6) M. These data indicate that oxiracetam has a protective effect against neuronal dysfunction and that this effect develops at a lower concentration than those of indeloxazine and bifemelane.

Animals↗
PubMed1990

Occlusive hydrocolloid dressings decrease keratinocyte population growth fraction and clinical scale and skin thickness in active psoriatic plaques.

Clinical studies suggest a therapeutic role for occlusion in the treatment of psoriasis. Previous studies, using multiparameter RNA/DNA flow cytometric analysis of epidermal suspensions obtained from active plaques, demonstrated increased keratinocyte growth fraction which reversed with successful medical treatment. Because keratinocyte growth fraction reflected disease activity, it was used in this study in addition to clinical evaluations in order to determine the efficacy of occlusion in the treatment of psoriatic plaques. In each of 9 patients, scale, skin thickness and erythema were compared in one occluded and one control plaque using an analog scale. Both scale and skin thickness, but not erythema, were decreased after 2 weeks of occlusion. However after 10 weeks, no additional differences were seen when compared with assessments made after 2 weeks, suggesting that the benefits of occlusive therapy occurred early. After 10 weeks of occlusion, the keratinocyte growth fraction was significantly decreased in occluded plaques. This study demonstrates that occlusion plays a synergistic role with other therapeutic modalities in ameliorating psoriatic plaques.

Bandages, Hydrocolloid↗
PubMed1990

From community mental health services to specialized psychiatry: the effects of a change in policy on patient accessibility and care utilization.

In 1975, a community mental health (CMH) centre with most of its resources channelled to outpatient services was set up in a defined catchment area of 75,000 inhabitants near Stockholm. In 1981, the CMH centre was allocated 3 inpatient wards of its own. An outpatient unit to treat long-term psychotic patients was also built up from existing resources. Emergency cases were directed to the primary health care services or to the emergency department of a hospital. During the same period, the number of doctors in the area's primary health care services increased fourfold. The social, demographic and diagnostic composition of the patient population and its utilization of in- and outpatient care in connection with these organizational changes are described. The population of the cathment area increased by 12.5% and the patient population decreased by 40%. The decrease was particularly great among first-time visitors (-54%), patients from lower social groups (-53%) and those with crisis diagnosis (-71%). The number of patients with psychoses increased (+26%). Outpatient visits and hospital utilization increased by one third. The number of compulsory admissions increased by 20% (still being far below the mean number in Stockholm). The decrease in the patient population is attributed to the reduction in accessibility to the CMH centre at a time when primary care services in the area were undergoing a sizeable expansion. The increased care utilization is the result of an internal redistribution of resources in favour of resource-demanding, long-term psychotic patients.

Adolescent↗
PubMed1988

Probability of transition into cell cycle does not depend on growth factor concentration.

When quiescent cells in monolayer culture are stimulated to proliferate with growth factor, the entry into S-phase or mitosis appears to follow first-order kinetics, with a probability to enter the cell cycle that depends on growth factor concentration (Smith and Martin, 1973). Suboptimal growth factor concentrations also lead to a decreased fraction of the cell population that responds to the stimulation (Brooks et al., 1984). Using flow cytometry, we have re-investigated this dual effect of growth factor concentration on cultures of quiescent normal human skin fibroblasts, stimulated with submaximal concentrations of fetal calf serum, epidermal growth factor, and platelet-derived growth factor. The size of the responding population decreased with decreasing concentration of growth factor, but the time course of cell division within this responding population was identical for all growth factor concentrations. This is in conflict with previous concepts and indicates that the entry into the proliferative state is based on a decision mechanism that cannot be adequately described using transition probabilities determined by mitogen concentration.

Bisbenzimidazole↗
PubMed1989

[Recent trends and prognosis of pulmonary diseases in Japan].

To determine trends of death rates for patients with chronic pulmonary diseases the author compiled the numbers of deaths per 100,000 Japanese population per annum based on the annual reports of the Japan Vital Statistics for the past 43 years. Death rates for the newborn population as well as for the younger population decreased while those for the aged population remained unchanged. Increasing numbers of deaths from lung cancer and decreasing numbers of death from pulmonary tuberculosis were noted. The death rate from the chronic obstructive lung diseases was maintained while the death rate for diffuse fibrotic lung diseases tended to be elevated. Baseline reference values for respiratory physiology parameters, established by the Special Commission for Respiration Physiology of the Japan Society of Chest Diseases, were presented by single linear regression equations represented in terms of age covering the subject's whole age span, including the aged population. The author carried out further analyses based on the data collected in a multi-center cross-sectional survey and concerning, some parameters found consistent differences the linear regression equation calculated for the aged population from those for the younger population. A longitudinal survey conducted by follow-up observations at Keio University Hospital to determine the annual decline of parameters on respiration physiology was designed to cover healthy subjects as well as subjects with chronic pulmonary diseases. Annual declines in vital capacity, forced vital capacity, forced expiratory volume in one second, arterial oxygen tension and arterial carbon dioxide tension showed linear changes throughout the entire age span. Some parameters, such as flow max at 25% vital capacity or alveolar-arterial oxygen tension difference (AaDO2), demonstrated statistically consistent differences in annual decline between younger and older age populations. The annual decline of parameters in patients with chronic pulmonary diseases demonstrated consistently larger values compared with those for healthy subjects. In a study on the pathophysiology and prognosis of patients with respiratory failure with/or without cor pulmonale extension of the survival period for the patients with cor pulmonale was demonstrated.

Adolescent↗
PubMed1992

[Quantitative changes in the lymphoid cell populations of the skin and regional lymph node after exposure to whole-body deep hypothermia].

The effect of general deep hypothermia on quantitative changes in populations of lymphoid cells in the skin and regional lymph node (LN) was studied in experiments in 20 male albino rats. The narcotized animals were cooled up to 18 degrees C of rectal temperature, kept at this temperature during 2h and then warmed up to 37 degrees C. Early terms of the posthypothermia period were characterized by less density of the population of intraepidermal lymphocytes and a simultaneous increase of their amount in the papillary and reticular layers of the derm without any changes in the hypodermis. Subsequently the lymphocyte population density in the derm was decreased, a little later their amount in the hypodermis was decreased. A simultaneous increase of the amount of lymphocytes took place in the area of postcapillary venules of the paracortical zone of LN. At the late post-hypothermal period the quantity of lymphocytes in the skin was restored. In the B-zones of LN less sizes of lymphoid nodules were noted as well as decreased population density (PD) of mitotically dividing cells, blasts and lymphocytes with pyknotized nuclei. A simultaneous increase of PD of plasmocytes took place in cerebral cords and elevated activity of alkaline phosphomonoesterase was noted in these cells. At the late posthypothermia period the area occupied by cerebral cords on the section was increased and correspondingly the area occupied by the cortical substance was decreased. A conclusion is made that resistant properties of the skin are activated after hypothermia procedures.

Animals↗
PubMed1992

Comparison of the effects of ethanol and chlordiazepoxide on electrophysiological activity in the fascia dentata and hippocampus regio superior.

Acute intoxicating doses of ethanol-producing blood alcohol levels of 120-200 mg% increase paired-pulse (PP) inhibition in the dentate gyrus of anesthetized rats suggesting that ethanol increases recurrent inhibitory processes (Wiesner, J.B., and S.J. Henriksen (1987) Ethanol enhances recurrent inhibition in the dentate gyrus of the hippocampus. Neurosci. Lett. 79:169-173). To further understanding of the neuronal mechanisms underlying this phenomenon, the authors studied the effects of the benzodiazepine (BZ), chlordiazepoxide, and acute intoxicating levels of ethanol on extracellular field potential recordings and single-unit activity in the dentate gyrus and area CA1 of the hippocampus. In the dentate, ethanol had no effect on population excitatory postsynaptic potential (pEPSP) amplitudes or slopes; decreased population spike (PS) amplitudes (25%); increased PP inhibition; decreased dentate granule cell (DGC) spontaneous activity (58%); had no effect on putative interneuron spontaneous activity; and markedly increased post field potential-evoked interneuron discharges (IDs, 218%). Chlordiazepoxide had no effect on pEPSP amplitudes or slopes or PS amplitudes; increased PP inhibition; decreased DGC (62%) and interneuron (72%) spontaneous activity; and markedly decreased IDs (89%). In CA1, ethanol had no effect on pEPSP amplitudes or slopes; decreased PS amplitudes (26%); had no effect on PP responses; decreased pyramidal cell (PC) spontaneous activity (39%); had no effect on interneuron spontaneous activity; and markedly increased IDs (97%). Chlordiazepoxide had no effect on pEPSP amplitudes or slopes or PS amplitudes; had no effect on PP responses; decreased PC spontaneous activity (41%); and had no effect on interneuron spontaneous activity or IDs. The results suggest that the BZs decrease principal cell excitability by postsynaptic facilitation of inhibitory processes, whereas ethanol decreases principal cell excitability indirectly by increasing the excitability of inhibitory interneurons.

Action Potentials↗
PubMed1977

Tick-borne relapsing fever: an interstate outbreak originating at Grand Canyon National Park.

During the 1973 summer season, 27 employees and 35 overnight guests at the North Rim, Grand Canyon National Park, Arizona, acquired febrile illnesses compatibel with relapsing fever. Sixteen cases were confirmed by finding Borrelia spirochetes in peripheral blood smears or inoculated Swiss mice. Retrospective surveys of 278 employees and 7247 guests at the park revealed that acquisition of illness was significantly associated with the persons sleeping in rustic log cabins and acquiring bites of "unknown" insects. From rodent nesting materials found in the walls and attics of cabins where cases had occurred, infective Ornithodoros hermsi ticks were recovered. Exceptional activity of ticks in human populations appeared to have resulted from a decreased population of the ticks' usual rodent hosts. Vector control activities consisted of spraying the cabins with residual insecticide, removing nesting materials, and "rodent proofing." This outbreak, the largest yet identified in North America, extends the known range of a principal vector and establishes the North Rim as an endemic source of tick-borne relapsing fever.

Adult↗
PubMed1979

Immune function in systemic lupus erythematosus. Impairment of in vitro T-cell proliferation and in vivo antibody response to exogenous antigen.

Peripheral blood mononuclear cells from 46 systemic lupus erythematosus (SLE) patients showed reduced ability to proliferate in vitro in response to the soluble antigen, tetanus toxoid, as compared with 96 normal controls. Special studies of 27 untreated SLE patients also revealed significantly decreased blastogenic responses to tetanus toxoid. In both the total and untreated SLE populations, decreased mean tetanus antibody titers also were found as compared with the control population. However, the reduction in antibody titer and blastogenic response was not strictly parallel. A limited immunization program was initiated in low-responding volunteers from the SLE and normal populations. Three out of four SLE patients did not develop a significant blastogenic response despite increases in anti-tetanus titers after immunization, whereas all normals showed significant increases in both blastogenic and antibody responses. The accumulated evidence indicated that the unresponsiveness was the result of a defect in T-cell function. Monocyte reactivity was demonstrated to be normal, and no evidence was found for the presence of suppressor cells, inhibition by immune complexes, or increased prostaglandins to explain the defect.

Antibodies, Bacterial↗
PubMed1991

Heated linoleic acid anilide: toxicity and relevance to toxic oil syndrome.

The present study was undertaken to investigate toxic potentials of linoleic acid anilide (LAA) and heated linoleic acid anilide (HLAA) and their possible role in the etiology of toxic oil syndrome (TOS). Male Sprague-Dawley rats were given 250 mg/kg of LAA or HLAA in mineral oil through gavage, on alternate days for 2 weeks (total 7 doses). Control rats received an equal volume of vehicle only. The animals were sacrificed at day 1, 7 and 28 following the last dose. Ratio of organ weight/body weight showed a significant increase in lung in LAA group at day 7 while spleen showed remarkable increases in both treatment groups at day 1 and 7. On the other hand, this ratio showed decreases in case of liver, brain and heart at some time points. Among blood parameters, red cell counts and hemoglobin content decreased at day 1 in both LAA and HLAA treated groups, while platelet counts showed an increase. Serum LDH, GOT and GPT activities significantly decreased at day 1 and 7 in both LAA and HLAA treated groups, however, these changes were more prominent in the HLAA treated group. Interestingly, at day 28, these serum enzyme levels recovered to control levels. Both LAA and HLAA treated groups showed a decrease in serum IgM levels at day 1, however, at day 7 only the LAA group showed a significant decrease. IgA levels significantly increased in both groups at all the time points studied and were more pronounced in the HLAA treated group. Similarly, IgG levels also showed increases in both the groups. In addition to serum immunoglobulin changes, alterations in the lymphocyte subpopulations were also observed. While T-cell population decreased, B-cell population remained unchanged. Among T-cell subsets, T-helper cells did not show any change while T-suppressor cells decreased significantly at day 1 in the LAA group and at day 1 and 7 in the HLAA group, but regained control levels at day 28. The biochemical and immunological alterations observed in this study as a result of LAA and HLAA exposure and more so by HLAA further support that the fatty acid anilides may play a role in the etiology of TOS.

Anilides↗
PubMed1976

Receptors for immune complexes on cells within a non-lymphoid murine tumor.

In this paper we present evidence that antibodies unrelated to the tumor cell can comprise part of the in vivo Ig surface coat of cells derived from the non-lymphoid murine tumor, TA3/St. This was shown by incubating TA3 cells originating from other OA or BSA preimmunized mice with radioiodinated 125I-OA and 131I BSA. Radioiodine-labeled 125I-OA specifically fixed to cells derived from TA3/St tumors originating from OA-preimmunized mice. On the other hand 131I-BSA was specifically fixed by cell populations from BSA-preimmunized mice. Incubation of these cells in vitro at 37 degrees C abolished the specific binding and antibody could subsequently be detected in the tissue culture medium. Radioiodine labeled purified soluble antibody-antigen complexes could also be bound to cells derived from freshly harvested TA3/St tumors but not to their in vitro propagated counterparts. Removal of phagocytic or adherent cells from these cell populations decreased the binding of the complexed antibody on freshly harvested TA3/St populations, but did not eliminate it. Inhibition of complexed antibody binding was obtained when TA3/St cells (an H-2a tumor) were pre-incubated with anti-H2a antiserum. Propagation of the tumor in an F1 hybrid (A X C57BL) in which host cells could be distinguished from tumor cells by using an anti H-2b antiserum showed that binding of the immune complex was mostly limited to host cells infiltrating into the tumor population.

Animals↗
PubMedDate not supplied

[Angkor. The mystery of the dead city and Anopheles dirus].

The desertion of Angkor, which during more than five centuries was the center of a glorious civilization, has long been a matter of mystery and conjecture. The discovery of the vectorial capacity of the jungle mosquito Anopheles dirus, its epidemiological importance in the emergence and spread of multidrug resistance in Plasmodium falciparum malaria, the wiping out of large populations after transfer or deportation of non-immune Khmers into forest areas can now easily explain the desertion of Angkor. In 1431, Angkor Thom, the capital of the Khmer kingdom surrendered to the Thai conquerors. Soon afterwards, the young king left the city in search of a new capital. As a result of the population decrease large surfaces of rice fields were abandoned and reinvaded by the jungle, the typical biotope of Anopheles dirus. Severe epidemics of Plasmodium falciparum then occurred in the non-immune population with very high mortality decreasing again the number of workers and, thus, creating a vicious circle resulting in the progressive but complete desertion of Angkor.

Animals↗
PubMed1976

Monoclonal B-lymphocytes in peripheral blood of patients with plasma cell myeloma. Relation to activity of the disease.

Antisera were produced in rabbits against idiotypic determinants of the myeloma protein from 3 patients with IgG-k myeloma. The antisera did neither cross-react nor react with normal immunoglobulin (Ig). Idiotypic Ig-structures were demonstrated by indirect immunofluorescence (IFL) on 70-94% of peripheral B-lymphocytes inuntreated patients. The total numbers of circulating B-lymphocytes were increased with a simultaneous decrease of T-lymphocytes. Only one of the patients had blood lymphocytes which stained for cytoplasmic Ig with idiotypic antiserum. The monoclonal lymphocyte population decreased gradually during treatment. Plasma cell counts in bone marrow, IgG concentration in serum and erythrocyte sedimentation rate decreased simultaneously, whilt the haemoglobin concentration increased. Very few monoclonal lymphocytes were present during remission. Later, the monoclonal lymphocyte population began to increase in 2 of the patients in parallel with clinical signs indicating relapse. It is concluded that presence of monoclonal B-lymphocytes indicates dissemination of the disease and that they may belong to the malignant cell clone.

B-Lymphocytes↗
PubMed1979

Proton magnetic resonance studies of 5,6-saturated thymidine derivatives produced by ionizing radiation. Conformational analysis of 6-hydroxylated diastereoisomers.

The conformational properties of ten 6-hydroxylated dihydrothymidine derivatives including the various diastereoisomers of 5,6-dihydroxy-5,6-dihydrothymidine, 6-hydroxy-5,6-dihydrothymidine and 5-bromo-6-hydroxy-5,6-dihydrothymidine have been studied by 250 MHz proton magnetic resonance in aqueous solutions. A close correlation has been established between the carbon-6 configuration and the osidic conformation. The increase in the amplitude of the puckering within the furanose ring compared to that of thymidine or 2'-deoxyuridine is more pronounced for the levorotatory (6S) nucleosides than for the dextrorotatory (6R) diastereoisomers. The importance of the 2' endo conformer population decreases in the following order: (-) greater than (+) greater than thymidine. The absence of destabilizing effects on the g+ rotameric population about the C(4')-C(5') bond denotes the lack of any interaction between the exocyclic hydroxymethyl group and the 6-hydroxyl function or the 2-keto group. The 5,6-saturated nucleosides adopt a preferential anti conformation. The comparison has been extended to syn nucleosides which show opposite trends in the sugar conformation and g+ distribution.

Magnetic Resonance Spectroscopy↗
PubMed1990

Radiosensitivity throughout the cell cycle and repair of potentially lethal damage and DNA double-strand breaks in an X-ray-sensitive CHO mutant.

The response to ionizing radiation of synchronized and plateau-phase populations of xrs-5 cells was studied at the DNA and cellular level. Induction and repair of DNA double-strand breaks (dsb) were measured by the non-unwinding filter elution technique. Biphasic survival curves were obtained throughout the cell cycle as well as in the plateau phase, suggesting the presence in the cultures of a radiation-sensitive and a radiation-resistant subpopulation. Delayed plating of plateau-phase xrs-5 cells did not significantly modify cell survival indicating a deficiency in the repair of potentially lethal damage (PLD). Post-irradiation treatment with araA further indicated a deficiency in the repair of a form of PLD sensitive to this drug in the radiation-sensitive subpopulation. The radiosensitivity of synchronized populations decreased as cells progressed through S. Cells in late S were found to be most resistant to radiation, whereas cells irradiated in G2 + M had a sensitivity similar to that of cells irradiated in G1. The decrease in radiosensitivity in S was tentatively attributed to an increase in the proportion of radioresistant cells in the cell population. Preliminary analysis of the results obtained, assuming the presence of two subpopulations showing an exponential response as a function of dose, indicated no change in the D0 values of the radiation-sensitive and the radiation-resistant component throughout the cell cycle. The D0 value of the radiation-resistant component was similar to the D0 of repair-proficient CHO cells. At no stage in the cell cycle were shoulder-type survival curves observed. Transient expression of the xrs-5 repair gene may underlie the observed variation of radiosensitivity throughout the cell cycle. This gene expression could occur either at random, in a subpopulation of cells independent of cell cycle phase, or in a specific manner related to gene replication and the hemimethylated state transiently found immediately thereafter. It is proposed that the resistant tail observed in the survival curves throughout the cell cycle is due to the former phenomenon, and the decreased radiosensitivity in late S to the latter. xrs-5 cells were found to be deficient in dsb repair in the plateau phase of growth, as well as in G1 and mid-S phase. The latter observation indicates that the reduction in radiation sensitivity in S is not associated with a modulation in the ability of cells to repair dsb.

Animals↗
PubMed1992

Epidemic and demographic interaction in the spread of potentially fatal diseases in growing populations.

The spread of a potentially fatal infectious disease is considered in a host population that would increase exponentially in the absence of the disease. Taking into account how the effective contact rate C(N) depends on the population size N, the model demonstrates that demographic and epidemiological conclusions depend crucially on the properties of the contact function C. Conditions are given for the following scenarios to occur: (i) the disease spreads at a lower rate than the populations grows and does not modify the population growth rate: (ii) the disease initially spreads at a faster rate than the population grows and lowers the population growth rate in the long run and the following three subscenarios are possible: (iia) the population still grows exponentially, but at a slower rate; (iib) population growth is limited, but the population size does not decay; (iic) population increase is converted into population decrease.

Animals↗
PubMed1978

Ca2+ binding, ATP-dependent Ca2+ transport, and total tissue Ca2+ in embryonic and adult avian dystrophic pectoralis.

Avian muscular dystrophy is an autosomal recessive genetic disease characterized by early hypertrophy and loss of function of pectoralis major. The disease is progressive, ultimately resulting in atrophy and heavy lipid deposition. Previous investigators have noted a decrease in the ability of the dystrophic sarcoplasmic reticulum to concentrate Ca2+. More recently, other investigators have shown an abnormal calcium uptake in avian dystrophic sarcoplasmic reticulum. They indicated, using freeze-fracture techniques, that a 90 A particle of the vesicle membrane exhibited a decreased population and suggested that they might be the ATPase involved in calcium transport. Our studies confirm earlier observations of a decreased rate of Ca2+ uptake and Ca2+ binding capacity of dystrophic fragmented sarcoplasmic reticulum vesicles which are isolated from both embryonic and adult pectoralis. These observations correlate in turn with a 75% drop in the Ca:ATP transport efficiency of the dystrophic sarcoplasmic reticulum determined by measuring the rate of 32Pi liberation from gamma-ATP32 during active calcium transport by the isolated sarcoplasmic reticulum SR. In addition, we have found a quantitative deficiency in a 65,000 dalton component of the dystrophic fragmented SR at the time of myoblast fusion by measuring 35S-Methionine incorporation into the SR, coupled to high resolution polyacrylamide gel electrophoresis and radioautography. Analysis of total tissue calcium by atomic absorption spectroscopy revealed a decrease in the total calcium content of dystrophic muscle.

Adenosine Triphosphate↗