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B Felix

Publications and source records attributed to B Felix.

7 recordsLinked to original sources
PubMed2001

Actions of endotoxin and morphine.

In summary, our current studies show that treatment with a bacterial endotoxin, lipopolysaccharide (LPS), induces the expression of mu opioid receptors in the rat mesentery. This induction may be mediated through IL-1's actions on mu opioid receptors. Morphine stimulates the expression of adhesion molecules in human brain microvascular endothelial cells (HBMEC) isolated from pathological tissues. Under pathological conditions, mu opioid receptor-dependent pathways may be modulated through the induction of mu opioid receptors, especially in endothelial cells. Treatment with morphine increases [14C]-inulin permeability of an in vitro microvascular endothelial cell barrier, and decreases endothelial cell viability. Morphine pre-treatment potentiates the effects of LPS on endothelial cell viability, and on LPS induction of IL-1beta secretion from 1alpha, 25-dihydroxy-vitamin D3-treated HL-60 human leukemia cells. Previously, it was suggested that an opioid-dependent pathway may be involved in the recovery from endotoxin shock (D'Amato and Holaday, 1984). Induction of mu opioid receptors by treatment with high doses of endotoxin suggests that mu opioid receptor-dependent pathways may be involved in mediating the response to endotoxins. Taken together, these data provide valid evidence for an association between endotoxins and opioid actions. These studies suggest that opioid-dependent pathways in disease or in endotoxin exposure may be modified by cytokine-induced expression of opioid receptors in endothelial cells. In a pathological condition, an alteration of the opioid-dependent pathway may be expected. When morphine is used for its therapeutic values, it may, indeed, potentiate LPS' effects in an adverse manner. From a clinical perspective, these data indicate that morphine and an endotoxin, such as LPS, may interact in a positive 'feedback type of reaction, and thereby modulate the body's immune responses with unexpected and detrimental results.

Animals↗
PubMed2000

Chronic cocaine alters hemodynamics and leukocyte-endothelial interactions in rat mesenteric venules.

We investigated the effects of chronic cocaine exposure on the microcirculation in the rat mesenteric venules under both non-inflammatory and FMLP-induced inflammatory conditions. Chronic cocaine significantly increased WBC rolling flux in both conditions, and potentiated FMLP-induced leukocyte-endothelial cell adhesion (LEA). In cocaine-treated animals, total WBC number increased by 91%, and the ratio of white blood cell to red blood cell velocity was significantly lower, while vessel diameter was unchanged. Chronic cocaine decreased serum levels of tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6), but had no effect on interleukin-1 beta (IL-1beta). Expression of intercellular adhesion molecule-1 (ICAM-1) was increased in mesenteric venules following chronic cocaine exposure, and may be one of the mechanisms underlying enhancement of FMLP-induced LEA. The increase in WBC count, WBC flux and LEA, and the change in cell velocity seen in the cocaine-treated animals could cause a decrease in effective vessel diameter and a change in intravascular resistance, and may underlie the progressive vascular damage seen in chronic cocaine-abusing individuals.

Animals↗
PubMed1992

[K.7 K.pote: an original experience in the promotion of condoms among youths].

The CRIPS is a specialised AIDS prevention center in the Paris metropolitan region. The Paris metropolitan region regroups 10 million inhabitants in its urban zone. This region is one of the most affected areas in Europe by AIDS and HIV infection, and contains more than 50 percent of the AIDS cases in France. As of June 30, 1991, the rate of declared AIDS cases in Paris was 8 for every one thousand inhabitants. At the beginning of the epidemic, AIDS basically concerned homosexuals in the center of Paris. Today, more and more young heterosexual drug users are affected. Adolescents from a low socio-economic background are often at risk of marginalization from the mainstream of society and thus at risk to become part of this new HIV affected population. They are often not reached by mass media, general public campaigns. In France, very little information materials are directly targetted to this young, socio-economically disadvantaged population. The CRIPS set out to devise a new prevention tool which would target young males from this population, particularly those in the 15-20 year age group. In preparation for the project, six months were spent on field research in the neighborhoods where the young people lived, worked and socialized. Interviews were held with young people themselves and adults in the area, particularly bar men and others working where the youth socialized.(ABSTRACT TRUNCATED AT 250 WORDS)

Acquired Immunodeficiency Syndrome↗
PubMed1984

Lateral hypothalamic relations with medial hypothalamus and limbic areas in geese.

Spontaneous unit activity was recorded in the posteromedial hypothalamic (PMH) and preventricular magnocellular (PVM) nuclei, septal area (S) and hippocampal formation (Hp). Modifications of cellular firing induced by lateral hypothalamic area (LHA) stimulation were examined. Both thiopental anaesthetized and chronic non anaesthetized geese were used. Thiopental appeared to significantly decrease the spontaneous discharge frequency of PMH neurons, and to block both orthodromic and antidromic activations elicited by LHA stimulation. The results indicated that LHA has a predominantly inhibitory influence on PMH as well as on PVM and septal area. The study of antidromic evoked responses in the four areas investigated (PMH, PVM, S, Hp) demonstrated that these structures in turn exert a feed-back control onto LHA. These results are compared with previous electrophysiological, anatomical and behavioral feeding data and an attempt is made to establish some comparisons between birds and mammals.

Animals↗
PubMed1984

A goose head holder device for chronic experiments.

A special device is described which allows experiments to be performed on chronic non-anaesthetized geese. This system is composed of two elements: one is fixed to the stereotaxic apparatus, the other is implanted on the goose skull. The use of ear bars and eye and bill pieces is thus eliminated. This non-painful adaptation is well tolerated by the bird. In addition, the position of the animal with regard to stereotaxic coordinates is unchanged. This technique provides an essential tool for furthering investigations on the central nervous system in geese.

Animals↗
PubMed1980

Effect of induced hypothalamic hyperphagia and forced-feeding on organ weight and tissular development in Landes geese.

The effects of induced hypothalamic hyperphagia and forced-feeding were studied in 30 geese of the Landes breed. They were housed in individual cages under a dark-light cycle of 12 hrs light-12 hrs darkness. Eleven geese with ventromedian hypothalamic (VMH) lesions and 8 controls were fed ad libitum. A third lot of 11 force-fed animals was pair-fed with the operated geese. The study lasted 4 weeks after an adaptation period to the new environmental conditions. The daily food intake of the geese and their weekly liveweight gain were monitored. After VMH lesions, the mean food intake of the geese increased by 169 p. 100 so that after each treatment their liveweight increased and they became obese (P less than 0.001). The tissue distribution of the group with lesions showed a higher amount of subcutaneous fat (P less than 0.05), while the mesenteric fat (P less than 0.05) was more abundant after forced-feeding. The liver weight was much higher in all cases; its increment reached 311 p. 100 in geese with VMH lesions and 193 p. 100 in the force-fed. However, those values were too low when compared to the means obtained by traditional forced-feeding. Hyperphagia in the geese was very marked as compared to that in rats, but it was insufficient to produce a considerable hepatic steatosis.

Animals↗