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C Roux

Publications and source records attributed to C Roux.

At least 19 recordsLinked to original sources
PubMed2025

One mother for two species via obligate cross-species cloning in ants.

Living organisms are assumed to produce same-species offspring1,2. Here, we report a shift from this norm in Messor ibericus, an ant that lays individuals from two distinct species. In this life cycle, females must clone males of another species because they require their sperm to produce the worker caste. As a result, males from the same mother exhibit distinct genomes and morphologies, as they belong to species that diverged over 5 million years ago. The evolutionary history of this system appears as sexual parasitism3 that evolved into a natural case of cross-species cloning4,5, resulting in the maintenance of a male-only lineage cloned through distinct species' ova. We term females exhibiting this reproductive mode as xenoparous, meaning they give birth to other species as part of their life cycle.

Animals↗
PubMed1992

Teratogenic Agent Information Centre: fifteen years of counseling and pregnancy follow-up.

The Teratogenic Agent Information Centre was set up 15 years ago in response to a growing demand from a medical profession struggling to cope with the problem of teratogenic risk. Our goal was to provide information on the real nature of the risk and to monitor all at-risk pregnancies so as to obtain data in a field where there are still, unfortunately, many gaps in our knowledge. The results of these 15 years have been most encouraging, in that physicians have been provided with specialized information and the follow-up of gestations had provided considerable clinical data, which has contributed to advancing our understanding in this domain.

Counseling↗
PubMed1992

Low bone mineral density in patients with inflammatory bowel disease.

To assess the prevalence and risk factors for low bone mineral density in inflammatory bowel disease, we studied 61 consecutive patients, mean age 36 +/- 11 years. Twenty-seven had a Crohn's disease and 34 ulcerative colitis (including 13 with ileoanal anastomosis). Three patients, two women and one man (32, 70, and 45 years old, respectively) had vertebral crush fractures. Bone mineral density measured by dual energy x-ray absorptiometry at spine and femoral level was more than 2 SD below normal values in 23% of the patients, all of them having received steroid therapy. Eighteen patients (29%) had never received steroid therapy; their bone mineral density was not different than those who had. Univariate analysis showed a positive correlation between bone mineral density and body weight or oral calcium intakes, and a negative correlation with steroid daily dose. After ileoanal anastomosis, bone mineral density was not different from other groups and showed a positive correlation with time elapsed since coloproctectomy. We concluded that bone mineral density is low in patients with inflammatory bowel disease and exposes them to the risk of bone fracture. Bone mineral density after ileoanal anastomosis may increase with time after surgery.

Absorptiometry, Photon↗
PubMed1992

Coexpression in humans by kidney and fetal envelopes of a 280 kDa-coated pit-restricted protein. Similarity with the murine target of teratogenic antibodies.

Experimental studies performed in the rat over the last three decades have shown that antibodies raised against kidney or yolk sac, which, in the rat, surrounds the embryo and serves as a placenta during the major part of pregnancy, induced fetal resorptions or malformations. It is generally considered that the teratogenic antibodies decrease internalization and degradation of maternal proteins by yolk sac epithelial cells leading to an inadequate supply of nutriments to the embryo. These observations demonstrating the pathogenic role of antibodies to fetal envelopes are of great potential interest in clinical pathology since most cases of fetal malformations in humans are of unknown cause. The authors have recently shown that the key teratogenic antibodies in the murine system were directed against a 280 kDa-coated pit protein (gp280) specific for the brush border of epithelial cells lining the renal proximal tubule and the yolk sac. This observation allows for the unique opportunity to search for a similar system in humans. In this study, the presence in humans of a protein closely related to murine gp280 is shown, as indicated by extensive immunologic crossreactivity, close apparent molecular weights, strong homology of bidimensional peptide maps, and restricted distribution at the organ and subcellular level. In addition to kidney and yolk sac, human gp280 was also detected within the coated pits of the placental syncytiotrophoblastic cells. When introduced in an in vitro rat embryo culture system, antibodies to human gp280-induced developmental anomalies in a dose-dependent manner. These observations indicate that the antigenic component of the murine model is present in humans and can give rise to heterologous antibodies that cause developmental anomalies, suggesting that the experimental model might be of significance in human pathology.

Animals↗
PubMed1991

Hyperparathyroidism in proximal femur fractures biological and histomorphometric study in 21 patients over 75 years old.

Proximal femur fractures in elderly people are more and more frequent. Falls and senile bone disorders are the risk factors of this fracture. In order to understand the mechanisms of these bone disorders, we studied 21 consecutive patients with this fracture using bone histomorphometry. Measurements of serum intact parathormone (PTH), 25-(OH)-vitamin D, 1,25-(OH) 2-vitamin D and osteocalcin have been performed in these 21 patients, included in a larger series. We excluded patients with renal failure (serum creatinine greater than 140 mumols/l), cancer, or previous metabolic bone disease. There were 19 female and 2 male patients, ranging from 75 to 96 years, (mean 84.9). We found a low frequency of cortical (2/21) and trabecular (3/21) osteoporosis. There was no case of clearcut osteomalacia. Following histomorphometric bone study, two patients showed a typical pattern of hyperparathyroidism, and in a third one, this condition seemed very likely. In these three patients who were among the oldest, and who had high levels of serum PTH, chronic renal failure and primary hyperparathyroidism could be excluded. High bone remodeling was frequent in our patients, as reflected by the enhancement of eroded surfaces (13 cases) and of osteoid thickness (7 cases). Intact PTH level was elevated in our series compared to normal values in adults (in accordance to the PTH elevation in the case control study in a larger series). These findings suggest a major role of a secondary hyperparathyroidism in senile bone disorders favoring proximal femur fractures. This hyperparathyroidism is probably secondary to mild calcium and vitamin D deficiency. It may lead to architectural bone changes favoring this fracture.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1991

Effect of clonidine on the circulation and vasoactive hormones after aortic surgery.

After completion of abdominal aortic graft, 29 patients received an i.v. infusion of placebo (n = 16) or clonidine 7 micrograms kg-1 (n = 13) over 120 min in a double-blind study. Cardiovascular variables were measured and plasma samples obtained up to 5 h after arrival in the recovery room, for assay of noradrenaline, adrenaline, vasopressin and renin concentrations. Noradrenaline, adrenaline and vasopressin concentrations decreased in the clonidine group throughout recovery (P less than 0.001, 0.05 and 0.05, respectively, vs placebo). Heart rate was less in the clonidine group (P less than 0.01). There was no significant difference in mean arterial pressure between groups. Stroke volume was larger (P less than 0.01) and there were fewer episodes of hypertension (P less than 0.05) and tachycardia in the clonidine group. In addition, a reduction in the number of circulatory interventions (P less than 0.05) and episodes of shivering was noted in the clonidine group. Mean (SD) postoperative volume requirements were larger in the clonidine group (total postoperative input: clonidine 1462 (604) ml; placebo 1064 (348) ml (P less than 0.05]. These data are consistent with the observation that clonidine modifies endocrine and circulatory status after major surgery.

Aorta, Abdominal↗
PubMed1991

[Influence of Chlamydiae serology and the presence of a pelvic inflammatory state on the results of in-vitro fertilization].

The authors investigated the influence of Chlamydiae serology and the presence of a pelvic inflammatory state on the outcome of in-vitro fertilization on the basis of an analysis of 116 stimulation cycles. The study included 71 female patients suffering from infectious sterility of tubular origin with distal lesions. Chlamydiae trachomatis serology was considered to be positive at IgG titers in excess of 1/64. When the serum test was positive, there was a significant reduction in the number of clinical pregnancies and the cleavage rate. The percentage of ectopic pregnancies (6 ectopic pregnancies out of 29 clinical pregnancies) was very high, particularly if the serum test was positive and a pelvic inflammatory state persisting after antibiotic treatment contraindicated microsurgery. Surgery was performed only in favorable cases and did not appear to have any negative impact on the outcome. The presence of a non-stabilized pelvic infectious state was correlated with a significant increase in the drop-out rate and the number of post-menopausal gonadotropin required to achieve stimulation. The fact that unexpected spontaneous pregnancies may occur after an unsuccessful attempt must be taken into account when sterilization or salpingectomy are envisaged in an attempt to improve the outcome.

Chlamydia Infections↗
PubMed1990

A prospective study of the incidence and nature of injuries to adult rugby players.

The incidence and nature of injuries occurring in 8 adult club rugby teams was followed prospectively during the 1988 rugby season. The findings were compared with those from two similar studies in schoolboy rugby players. A total of 114 injuries were sustained by 78 players; 85% of injuries occurred during matches. Injury was most prevalent during the first 8 weeks of the season and again after the mid-season break. Hookers (19%), wings (15%), fullbacks (11%) and centres (10%) were the players most often injured. Injury occurred most commonly when the player was tackled (26%), during open play (21%) and during the loose scrum (17%). Muscles (33%) and ligaments (32%) were the anatomical structures most often injured. Injury caused 35% of injured players to miss more than 35 days of rugby. Thirteen per cent of injured players did not play again for the rest of the season and only 14% of injured players returned to rugby after 7 days or less. Prolonged disability was associated with ligament injuries (57%), dislocations (17%) and fractures (10%).

Adult↗
PubMed1990

Teratogenic effect of the cholesterol synthesis inhibitor AY 9944 on rat embryos in vitro.

AY 9944 [trans-1,4-bis(2-chlorobenzylaminomethyl) cyclohexane dihydrochloride] is an amphiphilic cationic molecule. This chemical is an established inhibitor of cholesterol synthesis and is teratogenic in rats. The mechanisms of this teratogenicity remain to be clarified. This study used cultured rat whole embryos to ascertain whether AY 9944 had a direct effect on embryos, or whether its action was indirect, via the maternal cholesterol metabolism. Four experimental conditions were investigated: (A) controls; (B) 10 day untreated embryos were cultured in serum of treated rats; (C) 10 day untreated embryos were cultured in serum containing added AY 9944 (0-1,000 micrograms/ml); and (D) 10 day embryos from females treated on day 4 of gestation were cultured in normal serum. In group B there was no growth retardation; some slight nonspecific abnormalities were not significant. In group C, direct addition of AY 9944 to culture medium retarded growth and differentiation in a dose-dependent manner. No malformation was observed, but histological examinations showed numerous areas of cell necrosis, especially in the CNS. In group D, not only was growth retardation observed, but also characteristic malformations of AY 9944 teratogenesis, including pituitary agenesis. These results show that AY 9944 teratogenicity is initiated prior to day 10.

Abnormalities, Drug-Induced↗
PubMed1990

Human seminal plasma suppresses the chemiluminescence of polymorphonuclears without modifying phagocytosis.

The suppressive activity of human seminal plasma was confirmed on the luminol-amplified chemiluminescent reaction of human polymorphonuclears. This suppression was found to be dose-dependent and noncytotoxic. The responsible factor appeared to be a radical scavenger of low molecular weight, acting selectively on hydrogen peroxide. Correlation with glandular markers of semen indicated this molecule to have a prostatic origin. Neither crude seminal plasma nor this factor were found to suppress intracellular engulfment and killing of bacteria. This molecule seems to cooperate with the other semen antioxidants to protect sperm cells from extracellular oxygen radicals.

Humans↗
PubMed1989

Thoracic and lower cervical spine involvement in a case of rheumatoid arthritis.

The authors report a case of spine involvement in a severe case of rheumatoid arthritis treated with corticosteroids. First, the patient developed acute back pain, related to costovertebral joints arthritis at levels T9-T10. Then, neck pain and cord involvement yielded to diagnosis of cervical interapophyseal joints arthritis; there was a C5-C6 subluxation which necessitated surgical treatment. The conjunction of these two rheumatoid localizations is an uncommon feature. Study by the CT scan is valuable when rheumatoid arthritis of the spine is suspected. Lower cervical spine subluxation, even severe, may be well tolerated. Surgery is necessary when there is medullary involvement.

Arthritis, Rheumatoid↗