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C Got

Publications and source records attributed to C Got.

17 recordsLinked to original sources
PubMed1992

Molecular dissection of a specific nuclear domain: the chromatin region of the ribosomal gene cluster in Xenopus laevis.

Molecular dissection of the nuclear domain corresponding to the ribosomal chromatin cluster was investigated. The experimental scheme was based on the ability of restriction enzymes to digest the whole genome without affecting this region (several megabases in length). Such a strategy involved the judicious choice of restriction enzymes, which is possible in Xenopus laevis, where the rDNA sequence is known and the repeated units are organized into one unique cluster. SalI, XhoI, and EcoRV digestion produced frequent cutting of the genome leaving the ribosomal cluster intact. Isolation of the rDNA cluster was confirmed by separation of the digested DNA by pulsed-field electrophoresis. When applied to purified nuclei, this approach allowed the isolation of the ribosomal chromatin cluster under very mild conditions: no cleavages (either enzymatic or mechanical) were detectable. Since the purification scheme depends only on the DNA sequence outside of the rDNA cluster, it permits the obtention of this domain in different functional states. Electron microscopic analysis demonstrated that the domain organization is substantially preserved and maintains its looped organization (the size and the full number of loops were preserved). This purification scheme provides a powerful tool for studying the structure-function relationships within the ribosomal nuclear domain.

Animals↗
PubMed1990

Supragenic loop organization: mapping in Drosophila embryos, of scaffold-associated regions on a 800 kilobase DNA continuum cloned from the 14B-15B first chromosome region.

The supragenic loop organization of the Drosophila genome was investigated on a 800 kilobase (kb) DNA continuum from the 14B-15B first chromosome region. Nuclear scaffolds from 0-18 hr embryos were prepared with Laemmli's low-salt, detergent procedure and digested with restriction enzymes. Scaffold-associated regions (SARs) were mapped by probing Southern transfers of total, scaffold-associated and free DNA with a set of 70 recombinant phages overlapping the investigated genomic region. In all, 85 restriction fragments showed association to scaffolds. 12 of them were present in the majority of scaffolds. They bore strong SARs organizing the DNA molecule as consecutive loops with sizes ranging from 15 to 115 kb. 44 were present in only a fraction of scaffolds. They contained weak SARs subdividing the basic loops into smaller ones. 29 additional restriction fragments were present in a very small fraction of scaffolds. The position of SARs with respect to transcribed regions was investigated. Strong SARs appeared to be located on untranscribed DNA and to frame transcription units. In contrast, at least some weak SARs were shown to comap with transcribed regions or to reside within characterized transcription units. Statistical analyses established that strong and weak SARs were periodically positioned on the DNA continuum and that there was a potential contact point between scaffolds and the DNA continuum every 11 kb, or multiples thereof. Implications for SAR role(s) are discussed.

Animals↗
PubMed1990

Developmental expression pattern of a 800 kb DNA continuum cloned from the Drosophila X chromosome 14B-15B region.

The expression throughout development of a long DNA segment from the Drosophila genome was investigated. A near continuum of 800 kb DNA was cloned by extending a 90 kb previous chromosome walk, spanning the rudimentary locus (r), and by initiating 2 chromosome walks from an isolated DNA clone located next to the r locus. Hexanucleotide-primed single strand cDNAs were synthesized from poly(A)+ RNAs prepared from staged embryos, larvae, pupae, males, females, heads from adults and thoraces plus abdomens from adults. The representativity of the cDNAs with regard to the whole length and the molar abundance of a selected gene mRNA was checked. These cDNAs were then used to probe Southern transfers of the cloned DNA after digestion with combinations of restriction enzymes. The limits of the expressed parts of the cloned DNA and their developmental profiles were then deduced. Data show that, in contrast to what was known on the basis of genetic analysis, this region of the Drosophila genome is densely transcribed. Numerous parts of the cloned DNA are found to be stage-, or sex- or territory-specifically expressed. Data are consistent with a view of the organization of this representative part of the Drosophila genome according to which the expressed regions tend to be clustered, whereas no tendency for transcription units displaying comparable specific spatial, temporal or sex expression patterns to be arranged in groups is noted.

Abdomen↗
PubMed1990

[Synovial osteochondromatosis of the knee and synovial chondrosarcoma. Report of 2 cases].

The possible transformation of synovial osteochondromatosis into chondrosarcoma is rarely reported in the literature, as well as the coexistence of the two entities. The authors have observed two such cases. The first one was discovered by arthroscopy in the course of a synovial osteochondromatosis associated with a posterior tumour proved secondarily as being a chondrosarcoma. On the contrary, the second case presented as a destroying tumour invading the entire joint and proved secondarily as being a benign osteochondromatosis. Cartilaginous masses very important may lead to bone destruction in the course of benign osteochondromatosis. However, in such cases, the possibility of an associated or a secondary chondrosarcoma must be looked for using radiology, arthroscopy and microscope examination.

Chondromatosis, Synovial↗
PubMed1989

[Beta-2 microglobulin and amyloid osteoarthropathy in patients undergoing chronic hemodialysis].

The incidence of beta-2 microglobulin amyloidosis was assessed in two populations of chronic hemodialysis patients. Out of 34 patients who underwent biopsy during orthopedic surgery (33 cases) or autopsy (1 case), 26 had amyloid deposits which fixed anti-beta microglobulin serum. Out of 55 unselected patients treated for over months at the dialysis centre, 14 (25%) had clinical symptoms suggesting amyloidosis and out of 43 patients who had a systematic radiological skeletal survey, 23 (53%) had bone deposits. The plasma beta microglobulin concentrations (about 20 times the normal value) we not significantly different whether or not the patients had histological proven amyloidosis, clinically or radiologically probable amyloidosis, no detectable amyloidosis. However, the duration of hemodialysis was longer in those with proven or highly probable amyloidosis. The finding illustrate the indirect role of elevation of beta-2 microglobulin in the genesis of this pathology and also the necessity of lowering its concentration in order to avoid the long term complications of osteoarticular deposits, the functional consequences of which may be very serious.

Adult↗
PubMed1989

[Osteonecrosis of the femur head in patients with renal transplant. Apropos of 82 surgically treated hips].

Fifty-six renal transplanted patients having an average age of 33 years have been operated on for necrosis of the femoral head from 1973 to 1988. They totalise 85 cephalic necrosis due to the therapeutic peaks of corticotherapy. The femoral condyles were affected by the necrosis in 21 patients, and the humeral head in 16 patients. 82 surgical operations of first intention and 18 resumptions leading to 100 the total number of operations. The 26 drilling gave place to 11 by arthroplasty. The good results of the drillings only concern the infraradiological stages and the MRI allows to detect the non symptomatic stages 0. The 33 intermediate prosthesis did not lead to septic complications but 9 cotiloidal alterations of which 4 important with a resumption by total prosthesis. 36 total prosthesis were realized out of which 13 for resumption. Two early and two late suppurations after septicemia complicated the evolution. If at stage 0 or 1 the drilling seems to remain a reliable indication, the total prosthesis is the only possible solution for invalidating stages IV, the intermediate prosthesis seems to be able to keep a place in the intermediate stages.

Adolescent↗
PubMed1986

Biological markers of alcohol intake among 4796 subjects injured in accidents.

An epidemiological survey was carried out in France in 1982-3 to study the proportions of occasional and chronic drinkers among people injured in accidents of all kinds. The characteristics of 4796 victims recruited in the emergency units of 21 hospitals were recorded. Systematic blood sampling was performed to determine the blood alcohol concentration and two markers of chronic alcohol consumption--gamma-glutamyltransferase activity and mean corpuscular volume. Alcohol was present in the blood of 35% of the injured people, with concentrations exceeding 17.4 mmol/l (0.8 g/l) in one man out of four and in one woman out of 10. gamma-Glutamyltransferase values and mean corpuscular volume were also much higher than in a reference population of healthy subjects, indicating that most of the intoxicated subjects were probably chronic drinkers. This was confirmed by a discriminant analysis which showed an overall proportion of 30% of chronic drinkers among casualties. In France, therefore, the policy for preventing accidents should focus on chronic as much as on occasional drinking.

Accidents, Traffic↗
PubMed1978

[Shock].

Explore the source record for details and available documents.

Animals↗
PubMed1977

[Intestinal mechanical sutures: macroscopic and histological aspects (author's transl)].

The authors studied healing in digestive sutures carried out using automatic clips in the Dog. The mechanical conditions of the suture and in particular the absence of crushing are responsible for an almost perfect scar healing by first intention. The absence of ischemic necrosis remains the main factor differentiating these sutures from manual sutures where necrosis is constant, whether due to repeated trauma from forceps or ischemia due to tightening the threads, and above all, constant inclusion of the mucosa within the scar. The use of non-ischemic sutures explains undoubtedly the low incidence of fistulas, but explains, on the contrary, the large number of cases which bleed from the divided margins of the sutured or anastomosed layers; in rare cases, severe bleeding requires reoperation. These sutures are everted sutures causing a significant number of adhesions. We did not find any significant difference in the healing of inverted or everted sutures from the 15th day onwards.

Animals↗
PubMed1977

[Paraplegia and bilharziasis. A propos of 4 cases (including 2 confirmed cases of bilharzial myelitis].

Four observations of paraplegia of bilharzians are presented. In two of them the anatomical proof of medullar localization of parasitosis was obtained, once in vivo, only once after a post-mortem. Medical study enables us to spot 55 cases of bilharzian paraplegia, of which 25 sufficiently explicit on the clinical point of view, indicated medullar parasitosis. A parasitosis diagnosis must especially therefore be sought out with the greatest care so that the specific and remarkably active treatment may be started as soon as possible.

Adult↗
PubMed1975

[Aortic ruptures in traffic accident traumatology].

8 cases of rupture of the aorta seen in a series of 62 autopsies were studied in the context of a multidisciplinary enquiry into road accidents. In the light of these cases, the literature and experimental findings, different mechanisms are described, an essential step in the prevention of this lesion which is the main cause of death in 15 p. cent of cases.

Abdominal Injuries↗
PubMed1975

[Circular fractures of the skull base during traffic accidents].

With reference to 5 cases of circular fracture of the base of the skull occurring in relation to road accidents, the literature is reviewed. Two different types may be distinguished: --"compression" fractures, --"hyperextension' fractures, the latter being special on the basis of the site of the fracture line and the application of forces via the face or chin. Reconstruction of trajectories during accidents, on the basis of the anatomical lesions and the damage caused to vehicles, as well as the study of films made during the experimental reproduction of similar lesions, make it possible to explain the mode of production of these hyperextension fractures. Such understanding is essential to the study of safety precautions for vehicle occupants.

Acceleration↗