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P Thibert

Publications and source records attributed to P Thibert.

31 records · Page 2Linked to original sources
PubMed1982

Testicular atrophy in the spontaneously diabetic BB Wistar rat.

Complete gross and microscopic postmortem examinations were performed on 100 BB Wistar diabetic rats, 27 BB Wistar nondiabetic siblings, and 41 Wistar rats, and the incidence of testicular lesions was tabulated. Testicular atrophy was the predominant finding in all three groups of rats, but atrophy occurred at a much younger age in the diabetic rats. There was a strong relationship between the duration of diabetes and the presence of atrophy, which was stronger than the relationship between age and atrophy. The testicular atrophy observed in the diabetic rats was morphologically similar to the senile testicular atrophy in the nondiabetic rats. Histologic findings that were associated with increasing severity of atrophy were multinucleated giant cells in the lumens of seminiferous tubules, increased interstitial connective tissue, Leydig cell hyperplasia, and thickening of the tunica albuginea. Testicular atrophy has also been reported in human diabetics. Therefore, the BB Wistar rat may be a useful model for investigating this aspect of diabetes mellitus.

Age Factors↗
PubMed1981

The spontaneously diabetic BB Wistar rat. Morphologic and physiologic studies of peripheral nerve.

The spontaneously diabetic "BB" Wistar rat was examined for evidence of peripheral nerve abnormalities by a combined morphologic and physiologic approach. The studies were done on rats kept severely hyperglycemic and frequently ketotic. The peripheral nerves of the lower extremities, including the most distal nerves of the intrinsic foot muscles, revealed only minimal abnormalities by histologic and morphometric examination. Sciatic nerve conduction studies, however, measured over a 2-month period did not show a significant slowing in diabetics compared with age-matched controls, as well as between diabetics and weight-matched controls. In addition, fast anterograde axoplasmic transport studies were correlated with serum glucose results. Rats maintained severely hyperglycemic with or without ketosis had abnormal down flow rats of [3H]leucine compared to controls. Diabetic rats maintained with normal blood glucose levels showed no change in transport rates. These results suggested that persistent hyperglycemia in the "BB" Wistar rat produces significant physiologic but not significant structural abnormalities in the peripheral nerve.

Animals↗
PubMed1981

Spontaneous gastric erosions and ulcerations in BB Wistar rats.

One hundred thirty-four BB Wistar diabetic rats, 31 nondiabetic siblings, and 30 Wistar rats were necropsied. Gastric erosions and ulcers were observed in 43 (32.1%) of the diabetic rats and three (9.7%) of their nondiabetic siblings. None of the Wistar rats showed evidence of gastric mucosal injury. Lesions were most frequently found in the thick-walled, glandular portion of the stomach and were morphologically consistent with stress ulcers. BB Wistar rats may be valuable for studies on gastric stress ulcers.

Animals↗
PubMed1980

Control of microbial contamination in the use of laboratory rodents.

Historically, laboratory rodents have been used in preference to other animal species for biomedical research. Study disruptions and invalidations often have occurred due to microbial contaminants inherent to laboratory rodents. Today, many commercial suppliers and research institutions are controlling a variety of infectious diseases among laboratory rodents by careful design of animal facilities, by adaptation of managerial techniques employing precise operational policies coupled with careful supervision and attention to detail and the use of various diagnostic programs. The continued evolution of epidemiological practices, environment control systems, sophistication of barrier-sustained operations, preventative medicine and sanitation techniques, complemented by an improvement in veterinary diagnostic programs for disease surveillance further minimize microbial contamination of laboratory rodents. Such measures contribute to the fulfillment of various legislative requirements concerned with the quality of animals for biomedical research.

Animal Feed↗
PubMed1978

[Histochemical characterization of the tonic fibers in the flexor carpi radialis muscle of frogs (Rana temporaria, L.)].

In the flexor carpi radialis muscle of the Frog, extra-fusal muscular fibres with histochemical characteristics of tonic fibres were identified by reactions for enzyme activities, especially for myofibrillar adenosine triphosphatase. This evidence suggests no difference between the sexes in the organization of this muscle, in spite of a strongly marked sexual dimorphism.

Adenosine Triphosphatases↗
PubMed1976

[Tetanic fatigue and proximate post-tetanic recuperation in sartorius and flexor carpi radialis muscles of the male frog. Effects of iodoacetic acid (author's transl)].

The time-course of the isometric tension output, at 20 degrees C, during a long tetanus and after a short period of rest, was investigated in two isolated frog muscles : the sartorius and flexor carpi radialis muscles. To prevent aerobie and glycolytic recovery processes, some muscles were poisoned with 0,4 mM iodoacetic acid (IAA) and nitrogen, for 20 or 40 min. 1. For the unpoisoned sartorius muscle, tetanic tension declined quickly, but after a 0,8 sec period of rest, the muscle was able to develop high tension. Poisoning with IAA-N2 increased fatigue without suppressing the property of a proximate post-tetanic recuperation. 2. In the flexor carpi radialis muscle resistance to fatigue was very large before poisoning and diminished after poisoning. Proximate recuperation was very weak. 3. The results show that the recovery processes are not a primary factor of the development of the short-term fatigue ; they enhance the hypothesis that a failure of the electromechanical coupling can explain the rate of the tension fall in tetanized sartorius muscles.

Anaerobiosis↗
PubMed1975

Tonic properties of the Flexor carpi radialis muscle of the male frog (Rana temporaria).

The mechanical acitvity of the isolated flexor carpi radialis muscle (FCRM) of the mature male frog (Rana temporaria) was compared to that of the sartorius muscle. Muscles were stimulated directly by massive shocks at 20 degrees C and isometric tension was recorded during single twitch, twitch series, long tetani and long tetanus series. Some groups of muscles were poisoned with IAA-N2 or FDNB. The FCRM showed a high resistance to fatigue during a tetanus series and a "fatigue contracture" during a twitch series. The rate of the tetanic tension rise was smaller by five to six times than in the sartorius muscle (0 to 50% Po) and the twitch/tetanus ratio was always very small. During continuous activity and after the blocking of recovery metabolic pathways, FCRM used its energetic stores two to three times slower than the sartorius muscle. These stores did not seem to be more important. The results indicate that the FCRM is not a "tonic" muscle but, quite possibly, is composed of several types of fibre like many other frog muscles. However, some characteristics of mechanical response cannot be explained by the common classification into two types of fibre.

Animals↗