Changes in the learning ability of epiphysectomized rats

The experiments on rats have shown changes in the learning ability of animals. The learning of locomotor reactions of escape and avoidance conditioned reflex was accelerated in animals after pinealectomy. Training of rats in U-shaped and 16-door mazes was significantly affected after pinealectomy. The index of reflex retention (1 and 7 days later) was not changed in the operated animals. Epithalamin (0.5 mg/kg for 5 days) selectively facilitated learning of visual and space discrimination.     

Isolated capitellum humeri fractures in adults

From 2003 through 2009 we treated 35 patients who suffered from an isolated capitellum humerus fracture whom we treated with osteosynthesis. Patients who presented with concomitant fractures were not included. Thirty-four patients were categorized as Type I (Hahn-Steinthal) while one patient was Type IV (McKee). We describe the mechanism of injury and compared our results with works available in the literature. The average age of our patients was 38.6 years which was much younger than many articles about this type of injury found in the literature. The ratio of women to men in our study was 20:15. The surgical treatment was performed with various methods including: Kirschner wires, AO screws, Herbert screws and TwinFix screws. We discuss type of injury, days after injury operative treatment is performed, type of osteosynthesis used, the surgical approaches used for our treatment of capitellum humeri fractures, possible complications and our postoperative treatment. Results at the conclusion of treatment were excellent. Range of motion, shown in detail for each patient, was measured preoperatively, 1 month and 3 months postoperatively. We concluded that the major factors in successful treatment are how quickly the surgical treatment is performed after injury and early postoperative rehabilitation.     

Hyperglycemic effect of prolactin in anterior pituitary transplanted rats

The role of prolactin as a diabetogenic hormone was based on studies describing the ability of administered prolactin to raise the level of serum glucose. In the present study, female rats were made hyperprolactinemic by the transplantation of two anterior pituitary glands under the renal capsule, obtained from littermate donors. Chronic hyperprolactinemia increased blood glucose and impaired the glycolytic pathway of hepatic carbohydrate metabolism. However, basal serum insulin values were not different from those of controls. These data suggest that chronic hyperprolactinemia has an hyperglycemic effect and has a significant influence on glucose handling by the liver, through reduced glycolysis.     

External-internal relationships in humeri of modern human females

With data from an early twentieth century human skeletal collection, this exploratory study investigates associations between inner cortical and medullary cavity structures and outer shaft and epiphyseal features of a long bone. Humeri are measured directly in both whole bone and transverse section contexts; data along 2 axes at 2 sites are obtained. Twenty-two probable females, with an age range concentrated in middle adulthood, comprise the sample. Correlations between multiple external and internal bone measurements are analyzed, with the aim of yielding information on the physical nature of bone and on the effects of different measurement types, locations, and orientations for bone relationships. The study also examines whether prediction of inner humeral dimensions from outer measurements would be appropriate. Results indicate biepicondylar width and maximum length as the strongest external correlates of cortical dimensions. Contrasting with studies on the proximal femur, the humeral head shows external size changeability, mostly in the transverse plane, in response to modeling forces shared with the shaft. Epiphyseal measures are more highly associated with absolute rather than percent, and areal rather than linear, cortical variables. Medullary cavity dimensions are not significantly correlated with whole bone measures. Most associations demonstrate shape or proportion influences rather than a shared effect of linear body size. Regarding location and orientation, the distal site and medial-lateral axis display the strongest correlations among external and internal bone dimensions. In light of the demonstrated correlation patterns, prediction of humeral cortical quantity from external bone measures in living and skeletal populations would benefit from utilizing (1) biepicondylar width and maximum length; (2) an absolute, areal cortical measure; (3) a distal location; and (4) a medial-lateral orientation.     

Morphometric variation in Plio-Pleistocene hominid distal humeri

The magnitude and meaning of morphological variation among Plio-Pleistocene hominid distal humeri have been recurrent points of disagreement among paleoanthropologists. Some researchers have found noteworthy differences among fossil humeri that they believe merit taxonomic separation, while others question the possiblity of accurately sorting these fossils into different species and/or functional groups. Size and shape differences among fossil distal humeri are evaluated here to determine whether the magnitude and patterns of these differences can be observed within large-bodied, living hominoids. Specimens analyzed in this study have been assigned to various taxa (Australopithecus afarensis, A. africanus, A. anamensis, Paranthropus, and early Homo) and include AL 288-1m, AL 288-1s, AL 137-48a, AL 322-1, Gomboré IB 7594, TM 1517, KNM-ER 739, KNM-ER 1504, KMN-KP 271 (Kanapoi), and Stw 431. Five extant hominoid populations are sampled to provide a standard by which to consider differences found between the fossils, including two modern human groups (Native American and African American), one group of Pan troglodytes, and two subspecies of Gorilla gorilla (G. g. beringei, G. g. gorilla). All possible pairwise d values (average Euclidean distances) are calculated within each of the reference populations using an exact randomization procedure. This is done using both raw linear measurements as well as scale-free shape data created as ratios of each measurement to the geometric mean. Differences between each pair of fossil humeri are evaluated by comparing their d values to the distribution of d values found within each of the reference populations. Principal coordinate analysis and an unweighted pair group method with arithmetic averages (UPGMA) cluster analysis are utilized to further assess similarities and differences among the fossils. Finally, canonical variates analysis and discriminant analysis are employed using all hominoid samples in order to control for correlations among variables and to identify those variables that discriminate among groups; possible affinities of individual fossils with specific extant species are also examined. The largest size differences, those between the small Hadar specimens and the two largest fossils (KNM-ER 739, IB 7594), can be accommodated easily within the ranges of variation of the two Gorilla samples, but are extreme relative to the other reference samples. The d values between most of the fossils based on shape data, with the notable exception of those associated with KNM-ER 739 and KNM-ER 1504, can be sampled safely within all five reference samples. Subsequent analyses further support the inference that KNM-ER 739 and KNM-ER 1504 are different from the other hominid humeri and possess a unique total morphometric pattern. In overall shape, the distal humeri of the other fossils (non-Koobi Fora) are most similar to living chimpanzees. The distal humerus of Paranthropus from Kromdraai (TM 1517e) is most similar to one of the Hadar specimens of A. afarensis (AL 137-48a), whereas the first specimen of A. africanus from Sterkfontein (Stw 431) is not closely linked to any of the other australopithecines. The A. anamensis humerus from Kanapoi exhibits no special affinities to A. afarensis or to modern humans. © 1996 Wiley-Liss, Inc.     

Model of occlusion-reperfusion arrhythmias of the transplanted heart in rats

Rats with heterotopically transplanted heart were used for modeling of occlusion-reperfusion arrhythmias. Heart transplantation was carried out by performing the anastomoses between the recipient carotid artery and jugular vein and innominate artery and pulmonary artery of the transplant respectively. The reversible ischemia of myocardium was achieved through temporal occlusion of recipient carotid artery supplying transplanted heart. The model is characterised by total denervation of the heart, the absence of pump function, total nature of myocardial ischemia during occlusion of supplying artery, high reproducibility of arrhythmias and the opportunity of repeated use of the animals.     

Regeneration ability of fungiform papillae and taste-buds in rats

We have earlier shown that the taste-bud-bearing fungiform papillaeform a stable pattern on the tongue of rats. In this study theeffect of removal of the fungiform papillae in rats was investigated.The fungiform papillae on a 10 x 5-mm area on one side of thetongue were removed after mapping of both sides under an operatingmicroscope. Serial sections of five rat tongues within 1 dayof biopsy showed that all but one papilla were gone. After 4,6 and 12 months an average of seven papillae with taste-budswere found in the operated area, compared to 20, 26 and 23 inthe controls. Comparison of tongue maps before and after theseperiods showed that papillae had not migrated from areas outsidethe area of the biopsies. To test the assumption that the extentof biopsy determined the amount of regeneration, only the upperpart of the papillae with their taste buds were removed in 15rats. Complete regeneration of papillae and taste buds was obtainedwithin 14 days. The function of the regenerated taste buds wastested by bilateral recording from the chorda tympani propernerves. No difference in response amplitudes was observed betweenthe sides. When, however, the whole papilla including its basewas removed, neither the papilla nor the taste-bud regenerated.The results show that the ability of the fungiform papilla andthe taste-bud to regenerate after removal of the papilla isrelated to the extent of the biopsy. If the entire papilla includingits base is removed, it will not regenerate. If only the upperpart is removed, complete regeneration of both papilla and itstaste-bud will occur.     

Histochemical profile of articularis humeri muscle in the horse

In this study the histochemical fiber type analysis of the articularis humeri muscle of the horse was performed. This muscle is composed of type I and type IIA fibers. A large number of spindles has been observed and the presence of these receptors could help to understand the role played by this muscle.     

Human colonic cancer lines transplanted in athymic mice and rats

A number of human colonic cancer strains from operative specimens transplanted to nude mice and rats are described. Histologic characteristics of the strains completely correspond with those of the primary tumor. The strains contain mainly human cells, which is proved by 5 peaks of lactate dehydrogenase isoenzymes detected at electrophoresis in agar gel.