Age-related changes in rabbit articular chondrocytes.

Cell culture techniques have been used extensively in the study of the aging process at the cellular level. The "senescent" articular chondrocyte seems to be a good model to examine the responses to aging in osteoarthritis, one of the most frequent diseases of old age. Thus in vitro chondrocyte "senescence", established by weekly subculture was characterized by a declining proliferation rate during late passages, from a rapid growth rate in early subculture to a complete loss of the proliferation capacity after 8 +/- 1 passages. Flow cytometric analysis show a time course decrease in the fraction S and G2 + M during the subculture, and a concomitant enhancement in protein content related to the increase of cell size. The immunocytochemistry assays revealed an appearance of a rigid cytoarchitecture with an increase in the number, and organization, of three cytoskeletal components: actin, tubulin and vimentin. The cultured chondrocytes therefore undergo in vitro aging analogous to that described for diploid fibroblasts, and could constitute a cellular model for pharmacological and toxicological assays.

[Respiratory tract infections in the elderly living in institutions: prevention]. / Pathologie pulmonaire infectieuse du sujet âgé vivant en institution: prévention.

Pneumonia amongst elderly people living in institutions is common and is a frequent cause of mortality and hospital admission. It is important to distinguish between prevention of viral pneumonia, which primarily consists of influenza vaccination programmes, and prevention of bacterial pneumonia. Prevention of influenza infection in institutions requires the vaccination of as many as possible of both residents and caregivers. In the event of a declared epidemic then amantadine can be used to reduce the severity of, and complication rate of, influenza infection. The indications for giving this therapy need to be balanced against potential side-effects, especially neurological ones. For the prevention of bacterial pneumonia risk factors such as immobility or impaired swallowing should be first identified and dealt with as necessary. Anti-pneumoncoccal vaccination may be considered, but on current evidence, the value of systematic vaccination of residents has not yet been established.

[Pulmonary infections among the elderly living in institutions: prevention]. / Pathologie pulmonaire infectieuse du sujet âgé vivant en institution: prévention.

Pneumonia amongst elderly people living in institutions is common and is a frequent cause of mortality and hospital admission. It is important to distinguish between prevention of viral pneumonia, which primarily consists of influenza vaccination programmes, and prevention of bacterial pneumonia. Prevention of influenza infection in institutions requires the vaccination of as many as possible of both residents and caregivers. In the event of a declared epidemic then amantadine can be used to reduce the severity of, and complication rate of, influenza infection. The indications for giving this therapy need to be balanced against potential side-effects, especially neurological ones. For the prevention of bacterial pneumonia risk factors such as immobility or impaired swallowing should be first identified and dealt with as necessary. Anti-pneumoncoccal vaccination may be considered, but on current evidence, the value of systematic vaccination of residents has not yet been established.

[Psychosocial factors influencing the intention of women infected with HIV to have a child: study of 12 cases]. / Facteurs psychosociaux influençant l'intention des femmes infectées par le VIH d'avoir un enfant: étude de douze cas.

This study documents the factors that influenced the decision of 12 women of child-bearing age whether to have a child in the three years following an infection by the human immunodeficiency virus (HIV). Three of the 12 women are intending to have a child, and their intention stems from their beliefs and positive attitudes toward having a child, their partner's positive influence, the absence of their children, their denial of the disease and the absence of symptoms within their family. For the nine other women, the factors that influenced their decision not to have a child include the sociopolitical and economical context, the fact their family is complete, the fact they are seropositive or III, their fear of transmitting the infection and the idea of losing a child to AIDS.

[Hypothyroidism as the result of drug interaction between ferrous sulfate and levothyroxine]. / Hypothyroïdie secondaire à une interaction médicamenteuse entre lévothyroxine et sels de fer.

We report a case of drug-drug interaction between ferrous sulfate and l-thyroxin. A 95-year-old woman treated successfully with l-thyroxin for many years received ferrous sulfate for anemia. This association led rapidly to recurrence of hypothyroidism with elevated serum than TSH level which completely resolved after withdrawal of iron therapy. Interaction was confirmed after both drugs were daily administrated separately without recurrence of hypothyroidism.

War and peace in phylogenetics: a rejoinder on total evidence and consensus.

For more than 10 years, systematists have been debating the superiority of character or taxonomic congruence in phylogenetic analysis. In this paper, we demonstrate that the competing approaches can converge to the same solution when a consensus method that accounts for branch lengths is selected. Thus, we propose to use both methods in combination, as a way to corroborate the results of combined and separate analyses. This so-called "global congruence" approach is tested with a wide variety of examples sampled from the literature, and the results are compared with those obtained by standard consensus methods. Our analyses show that when the total evidence and consensus trees differ topologically, collapsing weakly supported nodes with low bootstrap support usually improves "global congruence".

Frequency of somaclonal variation in plants of black spruce (Picea mariana, Pinaceae) and white spruce (P. glauca, Pinaceae) derived from somatic embryogenesis and identification of some factors involved in genetic instability.

Plants of black spruce (Picea mariana, N = 7047 individuals) and white spruce (P. glauca, N = 3995 individuals) were regenerated from a total of 87 clones over a 5-yr period by somatic embryogenesis to study factors that might be associated with the appearance of variant phenotypes. Morphological evaluation of the plants showed several types of variation. These variations were grouped into nine types: dwarfism (type A), reduced height with various form anomalies (types B, C, and D), needle fasciation (type E), abnormality in tree architecture (type F), variegata phenotype (type G), and plants with an overall regular morphology but smaller than normal plants (type H). Plagiotropic plants were also observed (type I). Each plant from types A to H (except type C where no plants survived more than 6 mo) had retained its phenotype over 4-5 yr of growth. Some of the variant types could be related to chromosomic instability: chromosome counts showed aneuploid cells for type-A and type-D plants. The type I (plagiotropism) was not related to genetic instability but rather to physiological disorders. In total, spruce variants of types A-H were obtained at relatively low frequencies, i.e., 1.0% (39/3995) for white spruce and 1.6% (110/7047) for black spruce. Statistical analyses, conducted with family, clone, and time in maintenance as variables, showed that clone was the most important source of genetic instability followed by time in maintenance.