Left Hind Leg Research Articles

クロサンショウウオにみられた異常肢個体3例

Three adult Hynobius nigrescens with malformed legs were found in a sample of 165 specimens collected at Iwamuro-Mura, Niigata Prefecture, on March 7, 1979. In the left hindleg of specimen No. 1 metatarsal 2' arose from the basal part of metatarsal 2 and digit II' grew to the position of the underdeveloped digitus IV. In the right hindleg of specimen No. 2, brachydactylia resulting from poor development of the phalanges was seen. Specimen No. 3 had a foreleg-like dwarfish leg on the abdomen. The osteology of these malformed legs is described, and causative factors of the malformation are discussed.

Experimental muscular amebiasis in hamsters as a biological model

Trophozoites of Entamoeba histolytica maintained in vitro in Pavlova's medium were inoculated by deep intramuscular injection into the proximal left hindleg of hamsters. Thioglycollate medium was utilized as a successful vehicle to induce the infection. The invasion of the muscular tissue by the vegetative forms caused the formation of abscesses with great destruction of muscular fibers. The lesions were limited to the muscular tissue of the femoral area. The number of trophozoites, the medium of thioglycollate as a vehicle, the volume of the inoculum and the trauma caused by the needle were important elements in the evolution of the muscular amebic abscesses. A limited trial of the amebicidal activity of metronidazole utilizing the amebic intramuscular infection was also performed.

Local Tetanism, a Tool for Understanding the Stretch Reflex

Publisher Summary This chapter presents an experiment to study stretch reflex using local tetanism. Tetanus toxin is injected into the gastrocnemius muscle of the left hindleg of the cat. Tetanus toxin is transported in the motor fibers and reaches the spinal cord within 24 hr. After the appearance of the first symptom, a slight hobbling, the intoxication develops rapidly to a rigid extension of the whole hindleg of the injected side. At a very low dose, five minimum lethal doses/kg, the tetanic contraction could be observed only in the gastrocnemius muscle. Most acute experiments are performed at that stage of intoxication, when the symptoms are most highly developed. Cats are anesthetized with a mixture of urethane and chloralose. For the reflex tension experiments, the care was taken that the critical level of anesthesia is controlled in order to maintain a good stretch reflex. In the control experiments on non-intoxicated animals, the decerebration is performed under ether anesthesia that is ceased thereafter.

Oxygen tension in the abdominal cavity of hedgehogs during arousal from hibernation

Oxygen tension and temperature were measured in the abdominal cavity and heart frequency was recorded in hedgehogs, Erinaceus europaeus L. during arousal from hibernation. Oxygen cathodes of the dark type were inserted into the abdominal cavity through a small incision in the peritoneal wall. A small thermistor was inserted through the same incision to measure temperature. Heart frequency was recorded using needle electrodes placed subcutaneously in the right foreleg and left hindleg. Average oxygen tension at 15 min (T = 6.5 °C) into the arousal process was 11 mm Hg. Oxygen tension levels rose to 30 mm Hg over the next 30 min (T = 11 °C) then remained constant for 45 min (T = 21.5 °C) and finally increased to 43 mm Hg at 120 min (T = 32°C) after initiation of arousal. The oxygen tension pattern obtained is not fully understood on the basis of oxyhemoglobin dissociation characteristics and known circulatory conditions during arousal from hibernation. Body temperature and heart frequency increased continuously and their patterns were found to be comparable to those obtained by other investigations.

The effect of calcitonin on disuse atrophy of bone in the rat

In thirty female Sprague-Dawley rats the left hind leg was immobilized with plaster casts. According to treatment they were divided into the following groups: A) Control, no casts. B) No treatment. C) 50 MRC mU calcitonin (own preparation) in 5% gelatin subcutaneously per day. D) Vehicle alone subcutaneously. E) 50 MRC mU calcitonin (Ciba) in 5% gelatin subcutaneously per day. In addition, untreated rats without casts served as control (group A). After 6 weeks the femora and tibiae were X-rayed, weighed and examined histologically. The bones of the left and right legs did not differ in control group A. In groups B, C, D, and E a disuse osteoporosis had developed in the left legs (rarefication of trabecular bone volume of femur neck) which could not be seen in X-rays. Calcitonin treatment did not prevent the development of the bone atrophy. However, the pressure of the plaster casts had induced a periosteal apposition in some tibiae, and under calcitonin treatment the extent of this new formation in all femora and tibiae was markedly increased. The vehicle alone was ineffective. It can be concluded that whereas calcitonin is without effect on disuse osteoporosis, it probably favours new bone formation which is induced by other mechanisms.

Congenital lateral patellar luxation in a shorail dog: a case report

A shorail dog of 1.5 years old was admitted to the Teaching Veterinary Hospital, Chittagong Veterinary and Animal Sciences University with a clinical sign of weight bearing lameness of left hind leg. Physically and radiographically, it was diagnosed as grade IV lateral patellar luxation. Attempt was taken to treat the disease by combined tibial tuberosity transposition and trochlear resection. But after 8 months the symptoms attributed again as wire became torn and patella displaced laterally. Key words: Congenital, patellar luxation, trochlear resection, wire suture DOI = 10.3329/bjvm.v5i1.1329 Bangl. J. Vet. Med. (2007). 5 (1 & 2): 121-124

Slow potential changes from cat cortex and classical aversive conditioning

1. 1. The present study was designed to investigate variations in the amplitude of slow electrical potential changes (SPCs) recorded from motor and somato-sensory cortex of cats undergoing classical leg flexion conditioning. Eleven cats (the “learning group”) reached the behavioral criterion of 90% CRs. Eight cats who failed to reach conditioning criterion in 300 trials formed a “non-learning” comparison group. 2. 2. In the learning group negative SPCs from all cortical areas sampled showed decreasing amplitudes during habituation and extinction. All areas, with the exception of the motor cortex ipsilateral to the left hind leg of the animal (the leg receiving the UCS), showed similar decreases in amplitude during overlearning. Slow potential changes from the non-learning group showed consistent decreases only during extinction trials. In the learning group, negative SPCs recorded from contralateral motor and somato-sensory areas during conditioning showed greater mean amplitude than those recorded from the respective ipsilateral areas. In the non-learning group no significant differences appeared between contralateral and ipsilateral areas during CS-UCS pairings. 3. 3. No relation between SPCs and eye movement could be established. 4. 4. It was concluded that the SPC reflects two processes representing the activity of two or more subcortical systems. The equal bilateral changes in SPC amplitude seen in both the learning and non-learning groups were attributed to a diffuse activation via a system such as the midbrain reticular formation. The enhancement of negative SPCs restricted to the contralateral motor and somato-sensory cortices in the learning group, during acquisition, was attributed to a “localized” activation system. This could involve the nucleus ventralis lateralis and nucleus ventralis anterior of the thalamus. The diffuse system may be involved in the maintenance of general levels of “arousal”, or “activation”, a view commonly held. The localized system may be necessary for the elaboration and development of conditioned responding, but does not appear to be necessary for the maintenance of such behavioral activity.

Ligature-Incision-Suction Compared with Amputation in the Treatment of Rabbits Inoculated with Crotalid Venoms *

The results of treatment by amputation or by variations of ligature-incisionsuction (LIS) were compared in New Zealand rabbits inoculated with three lethal doses of either the cytotoxic venom of Crotalus adamanteus or the neurotoxic venom of Crotalus durissus terrificus, pit vipers of the Western Hemisphere. Reconstituted, whole, lyophilized venom was injected subcutaneously into the left hind leg of each anesthetized rabbit. The survival for more than 48 hours of 17 of 21 rabbits inoculated with the venom of C. adamanteus and treated by amputation 8, 15. or 30 minutes later confirmed the superiority of amputation in saving life; but the survival of 25 of 83 rabbits treated for 10 minutes by LIS begun ½, 1, 2, or 8 minutes after inoculation showed that LIS can also be effective against this venom in rabbits if used promptly, but not against that of C. d. terrificus. Local discoloration and necrosis caused by the venom of C. adamanteus were less when rabbits were placed with the inoculated side down than when they were not. Cooling combined with LIS in a few rabbits apparently did not affect the survival rate of animals inoculated with either venom; warming after prompt LIS in a small sample slightly increased the rate of survival with the venom of C. adamanteus only.

Effect of lymphangiography on metastasis.

Complications related to lymphangiography have been minor and easily treated in most instances. The possibility exists, however, that the passage of contrast material through cancerous lymph nodes may facilitate metastasis. This possibility became apparent to us after we viewed histologic preparations of lymph nodes removed from patients subjected to lymphangiography. The histopathology of these nodes revealed marked inflammatory changes, acute and chronic; replacement of portions of lymph node parenchyma by oil droplets; and decreased number of germinal centers (Figs. 1 and 2). Similar findings have been reported by Ravel (4), who studied a large series of nodes removed at varying intervals following lymphangiography. Our study was undertaken to determine whether lymphangiography affected tumor metastasis by any one or a combination of the following factors: (a) facilitation of metastasis from the marked alteration in lymph node architecture, (b) increase in blood-borne metastasis through lymphovenous shunts during or following the procedure, and (c) facilitation of metastasis within the lymphatic system from the increased intralymphatic pressure during the procedure. Materials and Methods One hundred three white female New Zealand rabbits, two to three months old and weighing 5–6 pounds, were used in the study. They were housed individually in air-conditioned quarters and given water and Rockland rabbit pellets freely. A modification of the technic of Zeidman and Buss (8) for tumor preparation and infusion was employed. The tumor used was the transplantable V–2 rabbit carcinoma which has been carried in our laboratory for the past three years. Tumor-cell suspensions were prepared by homogenizing small pieces of tumor tissue in physiologic saline. The homogenate was then passed through a sieve into a sterile test tube and packed in ice until used. A cell-viability count was made by Schrek's method (6). These suspensions were prepared to contain 1 × 106 ± 200,000 viable tumor cells per cubic centimeter. The animals were divided into three groups. In Group A (control animals), V–2 tumor suspension was infused intralymphatically into the afferent popliteal vessel of the left hind leg. Group B animals were subjected to direct lymphangiography with 1 cc of Ethiodol3 ten days prior to tumor cell infusion. Group C rabbits were subjected to direct lymphangiography ten days after tumor cell infusion. The rabbits were anesthetized with intravenous sodium pentobarbital. The medial side of the left hind leg was shaved and prepared with tincture of benzalkonium chloride An oblique incision over the medial aspect of the lower left hind leg was used to expose the afferent lymphatics. These vessels were usually found alongside a tributary of the great saphenous vein. To visualize the lymphatics 0.1 cc Direct Sky Blue 4 per cent4 was injected into the foot pad just before the procedure.

Comparison of the effect of cobalt-60 and 250-kv radiation on the bones of the rat.

This study was initiated when a well known therapeutic radiologist expressed the opinion that “the bone-sparing effect of cobalt 60 is a ‘spicule’ of the radiation therapist's imagination.” The argument that supervoltage radiation has a “bone-sparing” effect was adduced because of physical principles. Since then it has been questioned by numerous authors (1, 2), some maintaining that it is nullified by the lower biological effectiveness of supervoltage (1). Garland suggests the biological effectiveness of cobalt 60 is a factor of 0.8 of orthovoltage. It has been shown that roentgen rays of a h.v.l. of 0.4 mm. Cu produced twice the damage in cortical bone as roentgen rays of 2.4 mm. Cu, in terms of osteocyte destruction (Rosenthal and Marvin, 3). The same authors were unable to demonstrate differences in stunting of bone growth between the softer and harder radiation and this was attributed to cartilage being of soft-tissue density. In this attempt to compare cobalt-60 and 250-kv radiation we utilized the knees of the rat, one knee serving as a control and the other as the test subject. Microscopic studies were originally included in the final assessment, but have not been carried sufficiently far to warrant including the results in this report. Further, it had been intended to compare both modalities as to the relative effect on healing of fractures. It was discovered that the fractured femur of the rat does not heal,3 even when not irradiated, and thus ended this phase of the project. The study as originally devised also included plans to attempt to produce fractures secondary to high doses of radiation. It was found, however, that the animals carried out self-amputation, by chewing off the heavily irradiated leg. As presently constituted, this is a study of the radiological changes consequent upon irradiation. The rats used were four-week-old females, fed and housed under identical conditions. The technic of irradiation for 250 kv consisted of a beam with a Thoraeus 11 filtration and h.v.l. of 2.5 mm. Cu at 30 cm. distance. The cobalt 60 was administered at a distance of 70 cm. The electron build-up of cobalt 60 was increased by 5 mm. of wax bolus. It was recognized that an air gap, due to fur and irregularities of the leg, was present between the wax and the flesh, but studies in electron scatter have shown this is not significant (4). The rats were anaesthetized with Nembutal solution (1 mg./50 mg. rat weight) intraperitoneally. They were then strapped to a cardboard frame resting on a kapok backing and radiation was administered. Only the left hind leg of each rat was irradiated, the other serving as a control. The field was 35 mm. in diameter and the irradiation was centered just anterior to the knee joint (Fig. 1) and given in a single dose. Initially, a number of test doses were made to obtain, in general terms, information as to how long a waiting period was required and also to determine the generally useful dosages.

Disturbances and restoration of function in the hind legs of puppies following deafferentation

Long-term experiments were performed on puppies, aged 2–4 months, in which the left hind leg was deafferentated.

A Device for Holding Rabbits during X-Ray Photography

X-ray photographs are used extensively for investigating epiphyseal fusion to indicate the age of rabbits. In American research work the live animals were apparently held in position over the X-ray plate by hand (Thomsen and Mortensen, 1946; Hale, 1949; Petrides, 1951). Later, in New Zealand, Tyndale-Biscoe devised a strait jacket for holding the rabbits (Oryctolagus cuniculus L.) to avoid exposing the operators to radiation (Watson and Tyndale-Biscoe, 1953). The strait jacket was designed to hold rabbits of different sizes and to obtain different views of the leg bones. However, after being fastened, the rabbit could, by flexing or relaxing the muscles, alter the position of the leg. The changed position was not obvious until the plate had been developed, and repeat exposures, with a resulting waste of time and material, were necessary to ensure a series of pictures presenting similar views. It was found that a lateral view was sufficient, and further work by the Animal Ecology Section in New Zealand's Department of Scientific and Industrial Research led to the design of a more suitable rabbit holder. The device was made to restrain the left hind leg, so that a lateral view of the knee joint could be obtained. Fig. 1 shows the rabbit in the finished holder, ready for exposure. The foot and lower part of the leg rest in a groove at the base of the holder. Twisting of the leg is prevented by the angle at which the foot is held by a removable peg. The pelvis is held between the back of the holder and a buttress by a leather strap around the upper part of the right leg. The forequarters fit into a closely woven bag. There is less tendency for the rabbit to struggle when the eyes are covered, and the loose-fitting bag does not interfere with breathing. Three-ply wood is used for the back-board, base-board and upper side of the shaped groove. A spacer, cut to shape as shown in Fig. 2, is built up to suitable thickness with layers of ply wood. The upper side of the groove has been removed for the purpose of illustration; in normal use it remains fixed. An L-shaped bracket of ?/2-inch thick pine gives extra rigidity to the back-board, and serves as an anchorage for the broad end of the leather strap. The buttress (Fig. 1) is of %-inch thick pine. The base and back-board were assembled first in order to obtain the dimensions of the groove and positions of the bracket and buttress. A rabbit was held in the desired position, and pencil-marks made for guidance. Fig. 2 also shows the catch, made of spring wire, which holds the narrow end of the strap. The lower end of this is turned into the wood to prevent twisting, and two wire staples hold it securely. Throughout construction no specialised joints are used; screws and small nails are sufficient. All projections are rounded, and the holder given two coats of spar varnish to give a hard, smooth surface less likely to collect dirt. The over-all dimensions of the finished device are 24 X 6 X 614 inches and the weight just under 4 pounds. The use of this holder results in clearer photographs being obtained with a considerable saving of time. With it, one technician can handle five

The Late Assyrian Royal-Seal Type

This year is a particularly appropriate one in which to revive the subject of the Royal Assyrian Seal, for it is exactly a century since the publication of Austen H. Layard's Discoveries in the Ruins of Nineveh and Babylon, in which —among so many other things that remain vivid and delightfully instructive —the royal character of the type of stamp seal under discussion was first suggested. The most recently discovered example of an impression of the Royal Seal was found some months ago at Nimrud.What are the common features found in the extant specimens of impressions of the Royal Seal? It is always a stamp seal, the outline of the engraved sealing surface being circular. The bearded king is shown standing, right foot forward, wearing the standard royal head-dress of the period, his clothing terminating slightly below the knees. His left arm is outstretched, the hand grasping the top of the head of a lion which faces him. The king's right hand holds a dagger which he is plunging into the lion's chest. The lion itself is rampant, left hind leg forward, left front paw hanging ineffectually close to the king's right thigh; the lion's right front leg is poised, ready to strike, behind the lion's head. As in the vast majority of ancient Mesopotamian representations of lions, its mouth is wide open and its tail curls in.

The work performance of normal rats given continuous intravenous injections of cortisone and of corticotropin.

DURING the past 20 years there have been a number of reports that normal animals can be made more resistant to fatigue by the administration of adrenal cortical extracts. One of us (DJI) has made several attempts to confirm these claims with negative results. One of our studies (Ingle, Nezamis and Jeffries, 1949) has been published. The present report is based upon positive results obtained by the continuous intravenous injection of either cortisone or corticotropin. methods Male rats of the Sprague-Dawley strain were obtained from the Upjohn breeding colony and maintained on Archer Dog Pellets until they reached a weight of 200±2 gms. The work test was carried out according to Ingle (1944). The animals were anesthetized with phenobarbital sodium and cyclopal sodium and were subjected to the stimulation of muscle immediately following hypophysectomy. The gastrocnemius muscle of the left hind leg was weighted with 100 gms. A Nerve Stimulator, Model B (Upjohn) was used to deliver 5 pulses per second.

Isolation of Eastern Equine Encephalomyelitis Virus from Naturally Infected Monkey (Macacus Philippinensis)

A native monkey was bought by an army officer from a Filipino in the vicinity of Manila about December 25, 1946. It was then given to a female civilian living in the Manila Engineers Compound (H Street), where it was kept. On April 14, 1947 it became sluggish and would not eat. On April 15 it had difficulty in walking and on the following day was brought to the Veterinary Section of the 3rd Medical General Laboratory with a flaccid paralysis of the left hind leg. It was caged, observed and sent to the virus section on April 17. The next day the paralysis involved the right hind leg. It was sacrificed for virus study on April 18, 1947. This monkey had been in contact with two other monkeys in the Manila compound and had also contacted humans living in the area. No symptoms of any central nervous system disease were observed in any contact.

Studies on the Bovine Electrocardiogram. I. Electrocardio-graphic Changes in Calves on Low Potassium Rations.

Four calves were placed on a semipurified ration which analyzed 0.10-0.12% potassium. Four control calves were given the same ration except that potassium was added to bring the level of this constituent to 0.35%. The animals were placed on this ration at 160 days of age. Previous to this they received whole milk and a small amount of hay and grain.Electrocardiograms were usually taken at monthly intervals, but for some periods more frequently. The electrodes, which were of the German silver plate type, were placed on the upper part of the 2 fore limbs and just above the hock on the left hind leg. The areas on which the electrodes were placed were clipped, cleaned and covered with electrode paste applied with vigorous rubbing.Serum potassium determinations were made on all calves at 2-week intervals, more often when deemed necessary, by a modification of the titrimetric method of Shohl and Bennett.1Plasma calcium, phosphorus, and magnesium determinations were carried out at weekly intervals in order to ma...

Effect of Methylcholanthrene on Latent Period of Breast Tumors in Dilute Brown Mice.

The production of breast tumors in non-susceptible female mice of strains IF, CBA, JK, and NH by subcutaneous injection of methylcholanthrene was reported almost simultaneously in England and in this country. Observations in this laboratory also indicate that methylcholanthrene may affect the production of mammary carcinoma in a strain of mice that is known to develop the tumors spontaneously. Breeding female dilute brown (Little dba) mice have a high incidence of spontaneous mammary carcinoma. Subline 212, on which our experiments were performed, has a lower incidence of breast tumors than other members of the strain. Forty-two identified breeding female mice of this line have been observed for at least one year. Fourteen of them developed one or more spontaneous breast tumors when 250 to 475 days old. The average latent period was 371.0 days. Most dilute brown mice died of leukosis if they were painted with methylcholanthrene solutions. The carcinogen was applied to the unepilated skin twice weekly with a No. 6 camel's hair brush. The site was changed with each painting in the following order: head, left hind leg, right hind leg, left foreleg, right foreleg, sacral region, abdomen, interscapular region, anterior thorax. None of the male mice that were painted developed breast tumors. Thirteen of 65 breeding females of line 212 that were treated with methylcholanthrene had one or more mammary carcinomata. (Table I.) They appeared between the 106th and 268th day of life. The average latent period for these tumors was 181.3 days. The duration of painting varied. No breast cancer was found among 75 virgin females that were treated similarly.

The form of the electrocardiogram in experimental myocardial infarction: III. The later effects produced by ligation of the anterior descending branch of the left coronary artery

One to four days after ligation of the anterior descending branch of the left coronary artery or one of its subdivisions, the anterior surface of the dog's heart was explored by means of direct and semidirect leads. In taking these leads, the exploring electrode was paired with an indifferent electrode placed on the left hind leg, and the connections were so made that relative negativity of the former electrode produced an upward deflection in the completed record. The curves obtained under these circumstances by leading directly from the epicardial surface of the infarcted region have a characteristic outline. The initial and usually the sole deflection of the QRS group is a tall summit. The downward movement which normally precedes the intrinsic deflection in direct leads from the ventricular surface is absent. The intrinsic deflection is likewise absent, or is greatly reduced in amplitude in which case it is often represented by a deep notch on the descending limb of the initial upward deflection. The RS-T segment and T-wave are usually represented by a U-shaped depression, sometimes followed by a small summit. Curves of similar form are obtained when the exploring electrode is separated from the epicardial surface by a pad of gauze soaked in physiological salt solution or by the precordial tissues of the intact chest wall. The curves in question are very much like those obtained by introducing the exploring electrode into the cavity of the left ventricle. They owe their characteristic form to the absence of the electrical forces normally produced by the portion of the ventricular wall deprived of its blood supply.

Influence of Acid Extract of Cattle Anterior Pituitary Gland on Bone Repair in Young Guinea Pigs

We have shown1 that a growth-promoting effect is exerted by acid extract of cattle anterior pituitary gland on bone and cartilage in young guinea pigs. The present investigation deals with the influence of this extract on callus formation and healing of fractured bones.Twenty-four fall and winter guinea pigs averaging from 130 to 300 gm. in weight were used in these experiments. Under deep ether anesthesia both tibia and fibula of the left hind leg as a rule were fractured in these animals. As exposure of the bone with the unavoidable removal of the periosteum was followed by unsatisfactory healing, the following procedure was used: After shaving the skin of the leg the bones were broken at about the middle of their shafts. The broken ends were carefully approximated, the leg fixed with a small wooden splint and tightly bandaged with adhesive plaster. Sixteen animals thus operated on were injected with from 1 to 1 ½ cc. of extract daily, while 8 others of similar size, weight and age were not injected and...

Susceptibility of Heart to Electric Shock in Different Phases or the Cardiac Cycle

In connection with an extended series of experiments on the effects of electric shock, the fact has been brought to light that shocks whose duration is a small fraction of the cardiac cycle have a marked difference in their tendency to cause ventricular fibrillation,. depending upon the phase of the cycle in which they occur. The shocks were tripped off by amplified cardiac currents after a controlled delay from a reference point in the electrocardiac cycle. The electrocardiogram together with the shock current and voltage were photographically recorded in time relation on a continuously moving film, which enabled checks to be made on the placement of the shocks in the cardiac cycle. Nearly 800 shocks with 60-cycle current of .03 and .1 second durations were administered to 92 anesthetized sheep in different parts of the cardiac cycle, with currents ranging from 1 to 17 amperes, through the pathway between the right fore-leg and the left hind-leg. A large proportion of the shocks which were given near the...