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PubMed1990

Homicide in the Nordic countries.

This article reviews and assesses previous studies of homicide in the Nordic countries and compares the main findings with those from other countries. In spite of the relative sparsity of data, the nature of the available information allows a reasonably reliable comparison to be made between different Nordic countries. Although findings from separate studies vary somewhat, some general trends have been noticed and seem to apply to most of the countries in question: in particular, changes that have occurred over the last 2 decades. Thus, all the Nordic countries have experienced an increase in homicide incidence during this period, and with some notable exceptions, this increase has been quite drastic. Certain other trends have been observed, such as the prominent role of alcoholism and drug abuse in homicide offences, as well as the relative increase in nondomestic offences. Homicide followed by suicide has decreased proportionately among males, whereas this trend has not occurred to the same extent among females, who are more frequently involved in domestic homicide. Methods of homicide have also varied somewhat during the last few decades. The case of homicide in Greenland is discussed separately in view of its special circumstances. Studies dealing with the various psychiatric and mental health problems related to homicide in the Nordic countries are discussed and a hypothesis is offered about possible sociocultural factors, in particular alcohol and drug abuse, that seem to be important.

Alcoholism↗

PubMed1978

Differential patterns of elastic fibers in scarring and non-scarring alopecias.

Elastic fiber stain (acid alcoholic orcein) reveals diagnostically significant differences between several types of alopecia of the scalp. A short outline of elastic fiber distribution on the normal hair follicle emphasizes the elastic coat of the follicular isthmus, the sparsity of elastic fibers on the cyclic lower portion of the hair root, and the presence in the neck of the dermal papilla of an elastin-like body which is formed anew with each hair cycle. This body provides a marker of the gradual shortening of successive anagen hairs in male pattern alopecia. Patterns of elastic fibers in the perifollicular and interfollicular dermis are helpful in differentiating idiopathic pseudopelade of Brocq from pseudopeladic states secondary to lupus erythematosus and other disease processes. Within the idiopathic group, the development of elastic fibres on the lower cyclic portion of the hair root identifies a sub-group that may have a different, non-inflammatory pathogenesis and is provisionally designated as fibrosing alopecia.

Alopecia↗

PubMed1995

Ultrastructural effects of topical tretinoin on dermo-epidermal junction and papillary dermis in photodamaged skin. A controlled study.

We examined the effects of daily topical application of 0.05% tretinoin cream on photodamaged Caucasian facial skin by electron microscopy. Specimens obtained pretreatment, after 6 and 12 months of tretinoin therapy (20 patients), and after 6 months of vehicle treatment (5 patients) were compared in a blinded fashion, with special attention to the dermoepidermal junction and papillary dermis. Baseline specimens disclosed various degrees of damage including reduplication of basal lamina, smudging and sparsity of collagen fibers, and nodular arrangement of degenerated microfibrils in the papillary dermis. No significant changes were observed at 6 months in the papillary dermis of either tretinoin-treated or vehicle-treated patients. After 12 months of tretinoin treatment, however, disorganized collagen fibers, which were conspicuous in 11 patients at baseline, were replaced by new well-organized collagen fibers in a wavy pattern in 6 patients. In addition, the amount of nodularly degenerated microfibrillar material decreased in 15 of 18 patients with this finding at baseline. In contrast, no significant change was noted in the number of anchoring fibrils per unit length of the lamina densa. These observations provide further evidence that topical treatment with 0.05% tretinoin produces papillary dermal reconstruction, for which more than 6 months of application were required.

Administration, Topical↗

PubMed1993

A cardiovascular health education program for rural schools.

Public understanding of cardiovascular disease (CVD) risk factors and primary prevention has increased, due in part to community prevention efforts. However, many segments of society are difficult to reach. Such groups still need public education to acquire the knowledge that can lead to behavior change. Community intervention programs in rural areas face the challenge of disseminating health information to widely scattered populations isolated by difficult terrain and weather, and restricted by the sparsity of channels for mass communication. School health promotion programs, because of the special role schools play in rural communities, can help reach rural populations. During a five-year period, the Otsego-Schoharie Healthy Heart Program, a state-funded community intervention program, provided presentations to 18% of the combined total population of two rural counties through its school-based component. It also helped promote other program initiatives by establishing linkages in the community. Schools provide an effective channel for health promotion efforts to reach rural populations.

Adolescent↗

PubMed1990

Neuropeptide Y in cortex and striatum. Ultrastructural distribution and coexistence with classical neurotransmitters and neuropeptides.

NPY-neurons in the striatum and cortex have many morphological and chemical features in common. They are intrinsic, medium sized, aspiny and exhibit ultrastructural characteristics typical of neurons undergoing active synthesis and release of peptides. Most of the NPY-neurons in the two regions coexist with somatostatin, exhibit high levels of NADPH-diaphorase and are resistant to degeneration associated with Huntington's disease. Ultrastructural analysis suggests that the ensheathment by glia and sparsity of asymmetric (putatively excitatory) inputs may render NPY neurons resistant to excitotoxicity. Although NPY-neurons receive few inputs, they make numerous contacts with dendrites within a small region of the neuropil. Among their targets are GABAergic neurons. These NPY-receptive GABA neurons differ from other GABAergic neurons in the vicinity in that they receive few other inputs along their somata and proximal dendrites. This suggests that NPY may exert more influence on a specific class of GABAergic neurons. Many more of the NPY-terminals are found at sites that would be strategic for the simultaneous modulation of the release of transmitters and postsynaptic responses. The differences among NPY-neurons in the striatum versus cerebral cortex are mainly chemical. Most notably, the NPY-neurons are GABAergic in the cortex and not GABAergic in the striatum. In addition, some of the NPY-axons in the ventral portions of striatum and cerebral cortex may be catecholaminergic, and thus originate in brainstem areas recognized to contain NPY and epinephrine or norepinephrine. NPY- and catecholaminergic fibers converge onto same dendrites. Thus, the two transmitters may interact through intercellular biochemical pathways postsynaptically. Finally, the sites where the two fibers directly contact each other may be where NPY stimulates the turnover of dopamine.

Animals↗

PubMed1975

Cerebellar hypoplasia of genetic origin in calves.

Within 2 years, following the introduction of 2 Shorthorn bulls from the same stud into an Australian Illawarra Shorthorn (AIS) herd, 16 calves were born with cerebellar hypoplasia. All affected calves were the progeny of one bull mated to the daughters of the other. All other progeny of these bulls, most of which were from AIS dams, were normal. Affected calves exhibited severe ataxia, consistent head movement and abduction of the forelimbs. Microscopic changes in the cerebellum included sparsity of cells of the granular layer, loss of Purkinje cells and narrowing of the molecular layer. Observations on the frequencies of normal and abnormal calves are consistent with the hypothesis that the condition is caused by an autosomal recessive gene for which affected calves were homozygous and which was introduced into the herd in heterozygous condition by both of the Shorthorn bulls. Evidence is given for an unusually high frequency of the gene in the stud of origin of the Shorthorn bulls and a procedure for reducing its frequency is outlined. The possibility of a viral or toxic aetiology is discussed but is considered to be an unlikely explanation for the condition in this herd.

Animals↗

PubMed1967

Calcium activation of frog slow muscle fibres.

1. Skinned muscle fibres were prepared from the tonus bundle of the frog iliofibularis muscle and the contractile response elicited by applied calcium ions was studied. The fibre type was determined by electron microscopy.2. Fast fibres shortened many times more rapidly than slow fibres, indicating that the slow contraction of slow fibres is an inherent property of the contractile mechanism.3. The extent of spread of contraction following local calcium application was much greater in slow than in fast fibres, a difference which is consistent with the relative sparsity of the sarcoplasmic reticulum in slow fibres.4. The ability of the sarcoplasmic reticulum of slow fibres to accumulate calcium was demonstrated by the in situ immobilization of calcium when oxalate solutions were added to the skinned fibre.

Animals↗

PubMed1977

A study of excitatory neuromuscular transmission in the bovine trachea.

1. The excitatory innervation of bovine tracheal smooth muscle has been studied with the sucrose-gap apparatus.2. Single 2 ms electrical stimuli applied to the whole tissue excited intrinsic nerves, and produced a small transient depolarization of the smooth muscle, the excitatory junction potential (e.j.p.). The e.j.p. caused a twitch-type contraction; twitches and e.j.p.s summated during repetitive stimulation but facilitation was not observed, and action potentials were never elicited.3. The effects of electrical stimulation could be abolished by atropine (5 x 10(-7) mol/l) and augmented by neostigmine (4 x 10(-6) mol/l), and were mimicked by exogenous acetylcholine (1.0 mug/ml).4. With the electron microscope, the density of innervation was found to be low (one axon per ninety smooth muscle cells). Axons were found in small groups in the clefts between bundles of cells, but no axons penetrated within the muscle bundles. Naked axon varicosities containing agranular vesicles were seen, but no axon approached within 200 nm of a smooth muscle cell.5. It is difficult to reconcile the sparsity of innervation with the dependence of the tissue on nerve excitation to initiate activity.

Acetylcholine↗

PubMed1985

The absence of spread of adaptation between rod photoreceptors in turtle retina.

Adaptation by weak backgrounds and the spatial spread of desensitization between rods was studied in the snapping turtle retina, Chelydra serpentina. Intracellular membrane potentials were recorded from these photoreceptors in an eyecup preparation. The kinetics and sensitivity of rod responses were changed significantly by large, very dim backgrounds. For the twenty-five most sensitive rods where the dark-adapted flash sensitivity, SDF, was greater than 1.0 mV/Rh*, Rh* being the number of effective photo-isomerizations per rod, the background intensity required to halve the amplitude of the linear range response averaged 0.21 Rh* s-1. The time-to-peak of the test responses was reduced up to 50% by these dim backgrounds. The desensitizing effects of full field backgrounds of various intensities on the responses to large test spots were measured. The dependence of incremental flash sensitivity, SF, on background intensity, IB, followed the form (FORMULA: SEE TEXT) where I0 is the background intensity which halved SDF. The same intensity dependence held for slit-shaped background fields that desensitized responses to small test spots. The desensitizing effects of large, very dim flashed and continuous backgrounds took several seconds to appear and decay to dark levels. This in conjunction with the sparsity of photons suggests, that the desensitization from a single photoisomerization can persist for several seconds. A comparison of the desensitizing effects of spot and annular backgrounds revealed that small spot backgrounds superimposed on the centered test spots desensitized rods more effectively than annular fields. This finding held true even when annular patterns produced a greater maintained hyperpolarization in the rods. Thus, there was no unique relationship between desensitization and the steady maintained hyperpolarization evoked by a background field. The dependence of adaptation on distance from the impaled rod was determined with slit-shaped background fields placed at different positions across the rod's receptive field. The desensitizing effect of displaced slit stimuli was found to decline much more rapidly with distance than excitation. Displacing the slit by 20 micron from the centre reduced its desensitizing effect by more than 1 log unit. In contrast, excitation fell to about 80% at the same distance (lambda ranging from 50 to 70 micron). The fall off of desensitization with distance matched the calculated fall off with distance of light scatter from a slit. No difference was noted in the kinetics of test responses in the presence of equally desensitizing, superimposed and displaced slits.(ABSTRACT TRUNCATED AT 400 WORDS)

Adaptation, Ocular↗

PubMed1992

Proteins encoded by the Escherichia coli replication terminus region.

The replication terminus region (31 to 35 min) of the Escherichia coli chromosome contains very few mapped genes (two per min) compared with the remainder of the chromosome, and much of the DNA appears dispensable. In order to determine whether, despite this, the terminus region consists of protein-coding sequences, we cloned 44 kb (1 min) of terminus region DNA (that surrounding trg at 31.4 min) and examined its ability to catalyze protein synthesis in vitro or in minicells. We were able to account for more than half the coding capacity of the cloned DNA with proteins synthesized in these systems, indicating that the sparsity of mapped genes in the terminus region does not result from a lack of identifiable coding sequences. We can therefore conclude that the terminus region is composed mainly of expressable, albeit inessential, protein-encoding genes.

Bacterial Proteins↗

PubMed1962

Gastrointestinal microflora of mutton birds (Puffinus tenuirostris) in relation to "limy" disease.

Mushin, Rose (University of Melbourne, Victoria, Australia) and Frances M. Ashburner. Gastrointestinal microflora of mutton birds (Puffinus tenuirostris) in relation to "limy" disease. J. Bacteriol. 83:1260-1267. 1962.-The aerobic bacterial intestinal flora of mutton birds, healthy and affected with "limy" disease, was investigated, mainly in birds from Great Dog Island, Bass Strait, Australia. A total of 1,274 specimens from gut on post-mortem and from cloacal swabs was examined. No indication was obtained of a pathogenic bacterial species concerned in "limy" disease. A study was made of the types of organisms and their distribution in the gut of mutton birds. The sparsity, or occasional absence, of aerobic bacterial flora in some birds, especially adults, was noticed. The "limy" birds, by comparison with normal chicks, had a richer flora more evenly distributed through the alimentary canal. A higher ratio of gram-negative to gram-positive bacterial types was recorded in chicks; adult birds had a lower or an even numerical ratio. The comparatively frequent occurrence of Proteus species, except P. mirabilis, and of irregular and intermediate coliform types was evident. Escherichia coli type I was not a constant inhabitant of the gut. The gram-positive flora consisted mostly of Staphylococcus saprophyticus, S. lactis, and Enterococcus. The possibility that "limy" disease may be caused by physiological factors is discussed.

Animals↗

PubMed1962

Stability of tobacco-mosaic virus, Marmor tabaci H, in solutions diluted beyond the end point of infectivity.

Thornberry, H. H. (University of Illinois, Urbana, Ill.) and B. B. Nagaich. Stability of tobacco-mosaic virus, Marmor tabaci H, in solutions diluted beyond the end point of infectivity. J. Bacteriol. 83:1322-1326. 1962.-Tobacco-mosaic virus (TMV) in crude plant extract and in a partially purified preparation was diluted in distilled water, 0.1 m potassium phosphate buffer, and 0.1 m sodium chloride beyond detectable infectivity by usual assays on 12 primary leaves of Scotia beans, Phaseolus vulgaris L. All assays were made with inoculum containing abrasive at pH 8.5 in 0.1 m phosphate buffer. Infectious virus was recovered from each highly diluted solution (10 liters at pH 7.5 and 4 C for 24 hr) by adsorption at pH 2.5 on Celite particles and desorption at pH 8.5 and 40 C with 100 or 150 ml of 0.1 m phosphate buffer. Thus, TMV is not irreversibly inactivated by such dilutions. To ascertain the infectivity of the virus at high dilutions, TMV in crude plant extracts at three dilutions (10(-6), 10(-7), and 10(-8)) was assayed on bean leaves (12 leaves for 10(-6), 120 leaves for 10(-7), and 1,200 leaves for 10(-8)). Infection was obtained from each diluted inoculum (10(-6), 26 total local lesions; 10(-7), 30; and 10(-8), 22). These data support the conclusions that TMV remains infectious at high dilutions and that the failure to obtain infection beyond the end point of infectivity by usual assays is owing to sparsity of infectious virus rather than to viral inactivation. In addition, they suggest that a single viral particle is capable of infecting a susceptible site.

Plant Leaves↗

PubMed2002

Effect of latent human immunodeficiency virus infection on cell surface phenotype.

Highly active antiretroviral therapy has succeeded in many cases in suppressing virus production in patients infected with human immunodeficiency virus (HIV); however, once treatment is discontinued, virus replication is rekindled. One reservoir capable of harboring HIV in a latent state and igniting renewed infection once therapy is terminated is a resting T cell. Due to the sparsity of T cells latently infected with HIV in vivo, it has been difficult to study viral and cellular interactions during latency. The SCID-hu (Thy/Liv) mouse model of HIV latency, however, provides high percentages of latently infected cells, allowing a detailed analysis of phenotype. Herein we show that latently infected cells appear phenotypically normal. Following cellular stimulation, the virus completes its life cycle and induces phenotypic changes, such as CD4 and major histocompatibility complex class I down-regulation, in the infected cell. In addition, HIV expression following activation did not correlate with expression of the cellular activation marker CD25. The apparently normal phenotype and lack of HIV expression in latently infected cells could prevent recognition by the immune response and contribute to the long-lived nature of this reservoir.

Animals↗

PubMed1975

Rheumatoid synovitis and joint disease. Relationship between arthroscopic and histological changes.

Arthroscopic and histological synovial features have been studied in forty-two patients with classical or definite rheumatoid arthritis. A total index of disease activity as judged arthroscopically correlates significantly with a total index of histological activity. In those patients who have dense, waxy looking villi, the intensity of the villus-proliferation is associated with lymphocytic infiltration of the synovium. No relationship between synovial lining cell proliferation and cartilage disease nor between sparsity of lymphocyte infiltration and cartilage disease could be established.

Arthritis, Rheumatoid↗

PubMed1983

Pseudomonas aeruginosa colonisation in an intensive therapy unit: role of cross infection and host factors.

Despite the sparsity of Pseudomonas aeruginosa in the environment colonisation and infection with this organism was found at several sites by selective culture in 20 out of 46 patients in an intensive therapy unit. Three patients developed Ps aeruginosa pneumonia. Serial serogrouping and phage typing identified multiple strains in the unit and in the same patient. Rectal carriage occurred in 16 patients but rectal strains did not subsequently appear in tracheal aspirates; strains varied in their affinity for the upper respiratory tract. Colonisation was not directly related to length of stay and was detected in 16 of those colonised within 24 hours of admission. In intubated patients, who were colonised more frequently than those not intubated, upper respiratory tract colonisation correlated strongly with low initial arterial pH values. Personnel were probably responsible for cross infection among patients when the unit was busy. Strain differences and the susceptibility of patients also influenced colonisation and infection. Elimination of major reservoirs of Ps aeruginosa and compliance with procedures to control cross infection remain essential if patients in hospital are to escape colonisation by the organism.

Cross Infection↗

PubMed1971

Do lymphocytes protect the rheumatoid joint?

The pathology of the synovial membrane in rheumatoid arthritis can be characterized by the prominence of two major features which appear to vary independently of one another. These are synovial lining-cell proliferation and infiltration with inflammatory cells, predominantly lymphocytes. In a series of 42 synovectomies from 36 patients it has been shown that extensive joint damage is associated with a synovial picture of marked lining-cell proliferation and a sparsity of lymphocytes. Cases with heavy lymphocyte infiltration tend to show less damage to articular cartilage and bone despite a similar duration of disease. These results have been compared with the picture in leprosy, where a similar pathological spectrum is associated with changes in cell-mediated immunity necessary for the control of infection.

Adolescent↗

PubMed1987

Familial giant hypertrophic gastritis (Ménétrier's disease).

Familial giant hypertrophic gastritis involving three generations is reported. A review of the literature, where approximately 200 cases are described, showed only few cases of familial occurrence of this disease, and only in siblings. Our findings suggest dominant heredity, but considering the sparsity of familial occurrence reported earlier, heredity seems to be of only minor pathogenetic significance.

Adolescent↗

PubMed1992

Solitary necrotic nodule of the liver: parasitic origin?

AIMS: To report further cases of solitary necrotic nodule of the liver and to study its nature. METHODS: Seven nodules were retrieved from 4000 necropsy and surgical liver specimens coming to light over the past five years. All of them satisfied the diagnostic criteria of solitary necrotic nodule: a solid lesion with a central necrotic core and a hyalinised fibrotic capsule containing elastic fibres. Their clinicopathological features were reviewed. RESULTS: The nodules were incidental findings at surgery or necropsy in four men and three women whose ages ranged from 48 to 79 years (mean 63.7 years). Four were found in the right lobe and three in the left. Six were subcapsular and only one deep in the parenchyma, with sizes ranging from 0.3-2.5 cm. Each of them was solitary, well demarcated, and round to oval with a firm, whitish rim and a core of yellowish white cheese-like to solid material. In addition to the basic architecture, there were a number of common and undescribed histological features: presence of varying numbers of small mural vessels with intimal fibrosis and obliteration, presence of cholesterol clefts and foamy cells among necrotic material, and sparsity of inflammatory cells. In the two cases where ghosts of degenerated cells and partially preserved liver reticulin pattern were noted, worms were identified, one being Clonorchis sinensis. CONCLUSIONS: The entity is believed to be a "burnt-out phase" of a variety of benign lesions. Parasitic infestation is another possible cause, and presence of ghosts of degenerate cells, partially preserved liver reticulin pattern, cholesterol clefts and foamy cells among necrotic material are auxiliary features pointing to such an aetiology. The variation in morphological fine details reflects both the lesion's diverse pathogenesis and the fact that it can be of varying duration.

Aged↗