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Human colon adenocarcinoma cells (WiDr) and Chinese hamster lung fibroblasts cells (V79) were incubated with different concentrations of 5-aminolevulinic acid (ALA), and the production of protoporphyrin IX (PpIX) was studied using several techniques. The amount of PpIX produced per cell increased with increasing ALA concentration according to different kinetics for the 2 cell lines. For both cell lines a cell density dependency of the PpIX synthesis was observed. For saturating ALA concentrations, 2-3 times more PpIX was produced per cell at a density of 5 x 10(4) than at a density of 5 x 10(3) cells/cm2. The photosensitivity of cells appeared to increase even more than the PpIX content, indicating a cooperative effect in inactivation. The PpIX production rate increased with cell size and was about 1.9 times higher for cells in the G2 + M phase than for cells in the G1 phase of the cell cycle. Neither cell size nor cell cycle distribution were significantly dependent on cell density.

This article presents new weight and height data collected during three large surveys of representative middle-aged and elderly men and women from Gothenburg in 1990-93. Based on these data, weight and height tables are provided as an aid in clinical evaluation. Additionally, weights and heights collected during previous examinations in the 1970s (Läkartidningen 1981; 78: 3152-4) make it possible to describe secular changes nearly two decades later. These comparative data suggest that height and weight have increased in both men and women. However, body weight has increased more than height, resulting in an increase in mean body mass index (RMI) in most groups, with the exception of 75-year old women.

Body composition including the amount, the proportion of body weight, and the distribution of body water are of profound interest to both gerontology and geriatric medicine. In this article, methods of estimating body water, the changes with age and in disease, and clinical implications are reviewed. There are many methods to determine body water, the methods having different properties regarding e.g. feasibility and validity. Validation should for the methods used be performed in the population and age group under study. Body water decreases with age, and increases or decreases of body water are common in diseases common in old age. This has obvious clinical implications regarding e.g. geriatric pharmacotherapy, and water and electrolyte therapy. The need for methods to estimate body water and for avoiding both underhydration and overhydration is obvious both in gerontological and geriatric research and in clinical geriatric medicine.

Primary chronic cold agglutinin disease (CAD) is a rare hemolytic disease caused by the production of cold agglutinin antibodies that bind to erythrocyte I/i blood group antigens at low temperatures. The binding is mediated by monoclonal IGHV4-34-encoded cold agglutinins. CAD is a disease of older individuals with a median age of 76 years and accounts for about 15 % of all cases of autoimmune hemolytic anemia. The estimated incidence of CAD is 1-4/106 worldwide. The aim of this study is to better characterize the underlying lymphoproliferative disorder in CAD patients by review of bone marrow histology, immunophenotypic and genetic analysis. The bone marrow trephine biopsies of 54 patients with CAD showed circumscribed intraparenchymatous nodules with small monotonous monoclonal B-cells (median infiltration: 10% of marrow cells) with a CD20+, IgMs+, IgDs+, CD27+, CD5-/+, CD11c-/+, CD23-, CD38- immunophenotype. Neither plasmacytoid cytological features nor expression of plasma cell differentiation-associated transcription factors IRF4, BLIMP1 and XBP1 were expressed. However, a limited number of mature monoclonal IgM+, IgD- plasma cells were present outside the lymphoid nodules and were diffusely scattered throughout the marrow. Thus, the bone marrow in CAD shows a characteristic lymphoid infiltration pattern that is different from lymphoplasmacytic lymphoma that typically shows an admixture of lymphoid cells, plasmacytoid cells and plasmacells and that, not infrequently, shows a peritrabecular localisation. Of interest, the MYD88 L265P mutation, typical of lymphoplasmacytic lymphoma, was not detected (17/17 cases, sensitivity 3 %). Somatically mutated monoclonal IGHV4-34 gene rearrangement was demonstrated in eight patients with frozen samples (mean sequence homology 95.4%). Unexpectedly, no mutations of BCL6 intron 1 were demonstrated, except in one patient. BCL6 intron 1 mutations usually accompany immunoglobulin gene mutations in B lymphocytes that have matured in the germinal center. In conclusion, the histological, immunophenotypic and genetic properties of CAD are proof that CAD is a lymphoproliferative disease that is distinct from lymphoplasmacytic lymphoma with which it has previously been confounded. The disease likely originates from B lymphocytes that have not matured in the germinal center. Disclosures: No relevant conflicts of interest to declare.

The uptake of the photosensitizers Photofrin II (PII), meso- tetra-hydroxyphenyl-porphyrin (m-THPP) and meso-tetra- hydroxyphenyl-chlorin (m-THPC) in REH-cells was studied by flow cytometry (FCM). The uptake kinetics were studied with and without metabolic inhibitors. The uptake of PII after 60 min incubation was roughly 50% lower in the presence of the metabolic inhibitors, suggesting a partly active uptake mechanism for PII in REH-cells. The accumulation of m-THPP and m-THPC was not reduced by the metabolic inhibitors. Incubating PII-loaded cells for 60 minutes in sensitizer- free medium reduced the fluorescence intensity by approximately 60%, but had only a minor impact on the fluorescence intensity of cells incubated with m-THPP or m- THPC, even when the washing medium contained 10% serum. The uptake per cell was 9.5, 16, and 11 times higher at 105 than at 107 cells ml-1 for PII, m-THPP and M- THPC in PBS, respectively. This was not solely due to depletion of dye from the medium, since the extracellular sensitizer-concentrations decreased less than 50%. Medium from suspensions of high cell density inhibited the uptake of the sensitizers in low cell density suspensions, indicating that the inhibition may be due to factors secreted by the cells.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The ability to catch scent continuously while running, which may be an essential skill for many animals of prey, requires that ambient air flows inward through the nose also during expiration. In this study on bird dogs, the direction of air flow was detected by measuring the temperature in the air inside the nostril. While resting, nose ventilation was synchronous with lung ventilation. While searching for ground scent, the dog was sniffing at a frequency of up to 200 s-1, a strategy which may create turbulence in the nasal passages and thereby enhance transport of scent molecules to the receptors in the ethmoidal cavity. When the bird dog was searching for game while running with its head high against the wind, it maintained a continuous inward air stream through the nose for up to 40s spanning at least 30 respiratory cycles. We suggest that expiratory gas flowing at high velocity from the trachea to the mouth cavity creates a lower pressure than in the nose thus causing an inward air stream through the nose during expiration by a Bernoulli effect.

Erythrocytes from patients with erythropoietic protoporphyria contain large amounts of protoporphyrin. The photosensitivity experienced by these patients is assumed to be due to a leakage of protoporphyrin from the erythrocytes and transfer to the skin, where protoporphyrin acts as a photosensitizer. The leakage of protoporphyrin from the erythrocytes has been offered as an explanation for the great variety in protoporphyrin content observed among erythrocytes in this disease. Based on density gradient separation of red cells, it has been concluded that all reticulocytes and young erythrocytes contain large amounts of protoporphyrin. From our results, density gradient centrifugation is not suitable for age separation of red cells from patients with erythropoietic protoporphyria. By developing a new method for isolation of reticulocytes and applying flow cytometry to determine protoporphyrin content in individual cells, it was observed that two populations of reticulocytes were present in patients with erythropoietic protoporphyria, one with and the other without protoporphyrin. The half-life of protoporphyrin in red cells was found to be 12-14 days, in contrast to 1-2 days described previously, suggesting a slower release of protoporphyrin from the red cells than previously anticipated.

Within the framework of the gerontological and geriatric population studies in Gothenburg, Sweden, the health of immigrants of non-Nordic origin was compared with that of native Swedes in a cohort of 70-year-olds born in 1922. Of the sample examined, 11.4 per cent were of non-Nordic origin, among whom the non-response rate was relatively high (48%). Although there were few differences in "objective" health criteria between the Swedish and immigrant subgroups, there were manifest differences in "subjective" criteria and quality of life. In view of the increasing proportion of elderly immigrants in the Swedish community, these findings need to be borne in mind.

Photodynamic therapy has been used for treatment of malignant cutaneous lesions. Photosensitizer has been topically applied, 5-aminolevulinic acid, with light delivered at 630 nm. A study of response rate to varying light doses was performed, it might seem that light doses of 40 - 50 J/cm2 is sufficient for superficial lesions. For nodular lesions higher light doses are needed. Some patients with tumors in the gastrointestinal tract have been treated with systemic administration of 5-aminolevulinic acid and re-treated with Photofrin in case of unsatisfactory results. From the preliminary material available 5-aminolevulinic acid seems less promising as a photosensitizer for internal lesions compared to dermal lesions.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The aim of this cross-national study was to describe and compare differences in functional capacity of 75-year old people in three Nordic urban localities. As the life-expectancy at the age of 75 differs between the Nordic countries, there is reason to look for similar differences in functional capacity, taking differences in socio-demography, lifestyle, living conditions and health into consideration. In 1989-1991, 400 75-year-old men and women were selected to represent 75-year-olds in a Danish, Finnish and Swedish city. They participated in examinations which focused on functional capacity and health, where identical questionnaires, tests, and equipment were employed. The methods employed were developed from the experience gathered during previous studies of epidemiology of ageing in Glostrup, Gothenburg, and Jyväskylä. Functional capacity is the dependent variable multifactorially related to age, health, living conditions, and life style. The data collection was performed with participation rates in the interviews of 85% in Glostrup, 83% in Gothenburg, and 92% in Jyväskylä. The participation rates in the laboratory examinations were 76%, 67% and 77%, respectively. Examples of differences in socio-demographic background, lifestyle and measures of health and performance in the three localities are given. The Nordic study on physical, psychological and social capacity of 75-year-olds was performed with sufficiently standardised methods to allow a comparison of the results. Similar comprehensive cross-sectional comparative studies of the elderly people have not been performed earlier. Local and cross-national results will be published in each field separately and in combination.

The ability to detect the direction of a track is of vital importance to animals of prey and is retained in many modern breeds of dogs. To study this ability, four trained German shepherd tracking dogs, equipped with head microphones to transmit sniffing activity, were video-monitored after being brought at right angles to a track where the position of each footprint was known. Three phases could be recognized in the dogs’ behaviour: (1) an initial searching phase, during which the dog tried to find the track, (2) a deciding phase, during which it tried to determine the direction of the track and (3) a tracking phase, in which it followed the track. During ten tests on 20-min-old tracks on grass, and ten tests on 3-min-old tracks on concrete, the dogs always followed the track in the correct direction (i.e. in the direction the track was leading). During the deciding phase the dogs moved at half the speed and their periods of sniffing lasted three times as long as during the other two phases. The deciding phase lasted 3–5s, while the dogs sniffed at 2–5 footprints. The dogs’ ability to determine track direction in this time must rely on accurate methods of sampling air and a remarkable sensitivity for certain substances.

A representative sample of about 1000 70-year-olds in 1971/72 was included in the longitudinal and cross-sectional population study of elderly people in Gothenburg, Sweden (H70). The objectives were to make a survey of the social and medical conditions of this population, to obtain basic data for planning the care of the elderly, to contribute to the knowledge of normal aging processes and of normal criteria within the age group, and to offer a thorough medical examination. The survivors have been examined longitudinally at ages 70, 75, 79, 81, 82, 83, 85, 88, and 90 years of age. As possible cohort effects during 5-year-periods are also an object of interest, a further two cohorts have been examined at age 70, 75, and 79, and 70, 72, and 76, respectively. Another 75-year-old cohort has also been included (the Nordic comparative study of 75-year-olds-NK75). Using mainly identical methods, but different additional examinations, three Nordic countries cooperated in a comparative study of functional aging within the framework of the gerontological and geriatric population studies during the period October 1990-May 1991. The other centers were the universities of Copenhagen and Jyväskylä. The study aimed at comparing functional ability and biological aging between elderly in the Nordic countries. On an average, 3000 to 4000 variables about aging and diseases in old age are being collected per subject.(ABSTRACT TRUNCATED AT 250 WORDS)

Flow cytometry is a method for measuring the fluorescence and light scattering of individual cells in large numbers. By labelling the cells with fluorescent molecules that bind with high specificity to one particular cellular constituent it is possible to measure the content of the constituent. Such a fluorescent tag may be either a dye molecule with a high binding specificity for the particular component to be measured or a fluorescence conjugated antibody. The light scattering of the cells gives information on their size and to some extent also on shape and structure (Salzman et al. 1979, 1990).

Chromatin structure-dependent binding of the DNA-specific dye 7-aminoactinomycin D (7-AMD) in leukemic and normal cells in bone marrow aspirates from childhood acute leukemia patients and patients without bone marrow neoplasia was assessed by multiparameter flow cytometry. Simultaneous staining with fluorescein isothiocyanate-labeled antibodies was needed in many cases for determination of the immunophenotype of the cells that exhibited differential binding of 7-AMD. 7-AMD binding was enhanced in normal (4 patients) and malignant (8 patients) myeloid cells, and was generally low in normal and leukemic lymphocytes and normoblasts. Four of 18 aspirates from 16 patients with acute lymphoblastic leukemia contained neoplastic cells with increased 7-AMD binding capability. The 7-AMD binding of the leukemic cells was not correlated to S-phase fraction (P = 0.07), but was significantly correlated to cell size as measured by forward angle light scattering (r = 0.49, P = 0.007). Patients with tumor cells exhibiting low 7-AMD binding at last aspirate survived significantly longer than the patients with leukemic cells binding high amounts of 7-AMD (P = 0.03). Neither cell size, S-phase fraction, nor ploidy status predicted patient survival in this small scale study.

Flow cytometry (FCM) was used to investigate the effect of mitomycin C (MC) on the cellular uptake of Photofrin II (PII) in a cultured human colon adenocarcinoma cell line (WiDr). The surface area of the cells increased as they passed through the cell cycle from G 0 G 1 to G 2 M phase. MC retarded the cells in G 2 M phase and enhanced the surface area of the cells. A 1.3–2.3-fold increase in the cell surface area and a 1.3–2.7-fold increase in the cellular uptake of PII in the tumor cells was observed after 2 h – 8 h incubation with MC. Within each sample, an almost linear relationship between the intensity of PII fluorescence in the cells and the surface area of the cells was found. However, for the cells incubated with MC the surface area was not the only determinant of PII uptake. Effects of MC on the cell cycle, the cell surface area and the permeability of the cell membrane are suggested as possible reasons for the increase of cellular uptake of PII in the tumor cells.

The purpose of this summary is to convey an overall view of the technologies that are relevant to or are exhibited in today’s computer-based patient record (CPR) systems and also to highlight those technologies that will be required to build the state-of-the-art CPR systems of the near future. The needs of users of systems are the most important consideration in the design and development of any computer-based system. It is important that the designers and implementers of systems understand not only the users, but also how they will use the system and what demands they will place on the system to meet their evolving needs. Some of these users and uses have specific technologic implications of which designers of CPR systems need to be cognizant. In general, current CPR systems do not address the information needs of many of these users.

This article discusses The Computer-based Patient Record: An Essential Technology for Healthcare, the eagerly awaited report from the Institute of Medicine. The report presents the conclusions and recommendations of the multidisciplinary committee convened to explore how patient records could be improved, a project supported in part by AMRA.

1. Physiological adaptation to hypothermia were studied in newly hatched great snipe chicks (Gallinago media) by measuring oxygen uptake (VO2), heart rate (HR), respiratory frequency (RF), and body temperature (Tb) at different ambient temperatures (Ta). 2. Tb of 1-day-old chicks at Ta of 35°C stabilized at about 40°C. At Ta between 20 and 30°C the chicks maintained a Tb about 8°C above Ta. Hatchlings maintained a higher gradient when active than when resting. Below 20°C they were unable to maintain a stable Tb. 3. In resting hatchlings VO2 was similar at Ta between 35 and 20°C (Tb 40–30°C), VO2 range 1.7–2.5 ml·g-1·h-1. Below 20°C, VO2 declined with time. 4. The HR of 1-day-old chicks fell linearly with Tb during cooling. The Q10 of the HR was 1.7 at Tb 38°C and increased to 3.0 at 29°C. The RF showed a slight tendency to decrease with decreasing Tb. 5. It is concluded that the ability to maintain normal dexterity at low Tb is an important aspect of snipe survival strategy. Maintaining a temperature gradient rather than a constant high Tb presumably saves energy. It is suggested that the mechanisms whereby VO2 is maintained at a low Tb may involve isoenzymes and adaptations of the nervous system. However, such adaptations would not seem to affect the pacemaker mechanism as evidenced by the high Q10 of the HR.

The uniqueness of flow cytometry lies in the ability to perform quantitative measurements of individual cells in large numbers. By recording the fluorescence and light scattering of each cell as it is carried through the excitation focus of the flow cytometer in the course of a few microseconds, the cellular content of specific fluorescent constituents, or constituents that have been fluorescently labelled, can be determined together with information relating to cell size and structure. This ability to quantitatively characterize individual cells obviously has many important applications in marine microbiology. Although flow cytometers have been used to study marine microorganisms for several years, this field of applications is still in its infancy. That may in part be due to the technical problems encountered when trying to put the flow cytometer to work under the field conditions of a seagoing research vessel and on a type of specimens which in some respects are quite different from what current instruments were designed to handle. Flow cytometry was originally developed for measurement of cells in immunology and research in the biology of mammalian cells. Although it is being applied in other fields of biology as well, the bulk of applications is still limited to mammalian cells, a fact which is reflected in the design of the instruments that are now on the market. The majority of mammalian cells lie within a relatively narrow size range, i.e. 5 to 20 μm. With few exceptions they take on a spherical shape in suspension. They all have the same general chemical composition, and any endogenous fluorescence they may have is typically only a weak background, which is usually not a point of investigation in itself.

Two professional tracking dogs were brought in at right angles to 50-m-long tracks to try to identify the clues that the dogs used to determine the direction of the tracks. When the dogs were tested on tracks laid by a walking man, they took the direction that the track-maker had moved significantly more often than predicted by random choice regardless of whether the person had moved forwards or backwards. When tested on tracks laid by bicycling on grass or asphalt, the choice of direction was not significantly different from random, even though the dogs were always rewarded when making correct choices. When four leather strips were tied to the back tyre of the bicycle before laying the track, the one dog tested took the correct direction significantly more often than predicted by random choice. When the leather strips were smeared with sausage before laying the tracks, the dog took the wrong direction more often than predicted by random choice. However, when rewarded for making correct choices, the dog learned“ to choose the direction in which the bicycle had actually moved. We suggest that our dogs determined the direction of tracks by comparing the scents of consecutive prints and following the prints in the direction of increasing intensity.

A survey is in progress of the training in geriatrics given in Europe, and the status of such training in the Nordic countries is reported here. The Nordic countries--particularly Sweden--have a fairly long tradition of basic training in geriatrics and the research possibilities are also comparatively good. But the distribution of professorships, university departments, and basic training in geriatric medicine are still uneven in the Nordic countries.

We have investigated how the population dynamics of two types of vertebrates is influenced by food shortage. One type consists of animals which show indeterminate growth rate (cut the coat to the cloth) e.g. fish. The other type includes animals which show a determinate type of growth rate (require a minimum daily food supply to survive), e.g. mammals and birds. To this end we have developed a model which assumes that animals biomass is regulated by food biomass alone (i.e. no predation), while food biomass follows self-regulating dynamics. The model predicts stable biomass for the first type of animals and unstable, cyclic biomass for the other. The results help to explain why fish in a pond often develop a stable population of numerous, small individuals, while e.g. hares or moose on an island, shielded from predation, develop a fluctuating population

An isokinetic sampler for the determination of particle flux in flue gases, ventilators and ambient air was developed. Basically the sampler consists of a small cylinder which is open at both ends. During sampling its axis is oriented parallel to the flow lines. The fluid is allowed to pass isokinetically through a nozzle at the front end of the cylinder by means of its own inertia. The particles are charged and deposited on the cylinder wall. The cylinder acts as a collecting electrode in an electrostatic precipitator and its weight is determined before and after the sampling. The collection efficiency is above 90% for most particles. The sampler is battery-operated and its total weight is 2.3 kg.

A fraction of the erythrocytes from patients with erythropoietic protoporphyria contains large amounts of protoporphyrin. By extraction methods, only a mean value of the protoporphyrin content in erythrocytes is obtained. In this study, flow cytometry was used to determine the protoporphyrin content in each individual erythrocyte. The mean erythrocyte protoporphyrin fluorescence, calculated from flow cytometric data, correlated linearly to the mean cellular protoporphyrin concentration measured by ethyl acetate/acetic acid extraction. This indicates that flow cytometry gives a reliable quantitative determination of protoporphyrin in individual cells. Erythrocytes from patients with erythropoietic protoporphyria had a markedly skewed distribution of protoporphyrin. In the most fluorescent erythrocytes (protoporphyrin concentration 3.3 mM), there was about one protoporphyrin molecule for every sixth haeme molecule. This might explain the slight anaemia in some of these patients.

Nest humidity (\(P_{{\text{H}}_2 {\text{O}}} \)) under an incubating bantam hen was measured at ambient\(P_{{\text{H}}_2 {\text{O}}} \) ranging from 1.3 to 25.0 mmHg. Weight loss of eggs was recorded in clutches of varying size. Nest\(P_{{\text{H}}_2 {\text{O}}} \) and ambient\(P_{{\text{H}}_2 {\text{O}}} \) were also measured in wild incubating willow ptarmigan nests in dry and wet habitats.

The drop in phi/sub f/ with decreasing excitation wavelength, previously attributed to ionization from the S/sub 2/ state, increases substantially with increasing temperature for both indole and phenol in aqueous solution. Addition of 2-propanol to the solvent reduces the drop in phi/sub f/ but not its activation energy which on the other hand depends significantly on the solute. phi/sub eaq/-measured upon excitation of the S/sub 2/ state of indole in H/sub 2/O increases from 0.09 at 25/sup 0/C to 0.17 at 65/sup 0/C. The results are interpreted in terms of an intermediate charge transfer to solvent state (CTTS) populated from S/sub 2/. In the 2-propanol-water solvent the formation of this CTTS state appears to be governed primarily by interaction of the excited solute with water molecules. (auth)

The permeability of eel gills to ions, lipid-soluble and -insoluble substances has been measured under steady-state conditions. The results obtained support the multi-pathway model for transcapillary transport (Stray-Pedersen and Steen 1975). The gills are 7.5 times more permeable to THO than to Na+ or K+. Metabolic inhibitors do not affect the transfer of substances across the gills. Exposure to EDTA or MS-222 changes the permeability properties to resemble those of an aquous barrier. The gills are 10 times less water permeable than the capillaries of the rete mirabile.

The distribution of cellular and nuclear volume in synchronous populations of NHIK 3025 cells, which derive from a cervix carcinoma, have been measured by electronic sizing during the first cell cycle after mitotic selection. Cells given an X-ray dose of 580 rad in G1, were also studied. During the entire cell cycle the volume distribution of both cells and nuclei is an approximately Gaussian peak with a relative width at half maximum of about 30%. About half of this width is due to imperfect synchrony whereas the rest is associated with various time invariant factors. During S the mean volume of the cells grows exponentially whereas the nuclear volume increases faster than for exponential kinetics. Hence, although cellular and nuclear volumes are closely correlated, their ratio does not remain constant during the cell cycle. Volume growth during the first half of G1 is negligible especially for nuclei where the growth appears to be closely associated with DNA-synthesis. For unirradiated cells the growth of cellular and nuclear volume is negligible also during G2 + M. In contrast, the X-irradiated cells continue to grow during the 6 hr mitotic delay with a rate that is constant and about half of that observed in late S. Hence, radiation induced mitotic delay does not appear merely as a lengthening of an otherwise normal G2. During G1 and S the irradiated cells were identical to unirradiated ones with respect to all the parameters measured.

Over 50 B-cell derived lines and B-cell lymphoma and leukemia biopsies were screened for expression of the Epstein-Barr virus (EBV) receptor. The 13 sIgM-positive lines bound more than five times as much virus as the six IgG lines. Among the biopsies, the 17 sIgM, 11 sIgM and sIgD, and seven sIgG expressing biopsies were further divided according to expression of the C3 receptor. C3 receptor-positive biopsies, which expressed sIgM alone or along with sIgD, had the largest subpopulation of cells which expressed the EBV receptor (EBVR). C3 receptor-negative biopsies only expressed the EBVR on half as many cells as their C3 receptor-positive counterparts. However, the relative number of EBVR on individual EBVR-positive cells was independent of C3 receptor expression. Within the sIgG class, both C3 receptor-negative and positive cells expressed equally low levels of EBVR, both in terms of subpopulation and relative number of EBVR per positive cell. These results suggest that subpopulation expression of the EBV receptor is related to the C3 receptor but that relative number of receptors per cell is associated with sIg phenotype.