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1.
A two-year-old female miniature poodle died unexpectedly while romping with its owner. Anomalous origin of the left coronary artery from the left pulmonic sinus was discovered at necropsy. Histologically, the right ventricle was unremarkable, but multifocal to coalescing necrosis and fibrosis occurred in the myocardium and endocardium of the left ventricle. Medial hypertrophy of small muscular pulmonary arteries was observed in the lung. The cardiac lesions were similar to those of children with anomalous origin of the left coronary artery from the pulmonary trunk. Pulmonary hypertension, which is suggested by the pulmonary arterial medial hypertrophy, could have increased left ventricular myocardial perfusion and delayed the ischemic myocardial damage that resulted in the death of this dog.  相似文献   

2.
This study describes a rare congenital coronary artery anomaly in the Syrian hamster; namely, the separate origin of the obtuse marginal and left circumflex arteries which are the main components of the left coronary artery. The hearts of nine affected animals were examined by means of a corrosion-cast technique and histology. The hamsters belonged to a laboratory inbred family with a high incidence of coronary artery anomalies and bicuspid aortic valve. The aortic valve was tricuspid in three hamsters and bicuspid in the other six hamsters. In all cases, the right coronary artery was normal, whereas the left coronary artery main trunk was absent. The present anomalous coronary artery patterns could be classified into two main entities: (i) ectopic origin of the obtuse marginal artery from the right aortic sinus or from the right coronary artery, with the left circumflex artery arising from the left side of the aortic valve; and (ii) ectopic origin of both the obtuse marginal artery from the right aortic sinus or from the right coronary artery and left circumflex artery from the dorsal aortic sinus. In all cases, the obtuse marginal artery coursed to the right side of the heart through the ventral wall of the right ventricular outflow tract. When the left circumflex artery arose from the dorsal aortic sinus, it formed an acute angle with the aortic wall. This report seems to be the first to describe the separate origin of the main components of the left coronary artery in a non-human mammalian species. In man, the congenital coronary artery and aortic valve defects reported herein may entail the risk of clinical complications. However, none of the affected hamsters showed signs of disease.  相似文献   

3.
Congenital underdevelopment of one or more main branches of the coronary arteries has been reported in man, but not in non-human mammals. In man, this defective coronary artery arrangement may cause myocardial ischaemia and even sudden death . The main goal of this study was to describe the coronary artery distribution patterns associated with the presence of a markedly underdeveloped (rudimentary) coronary artery in Syrian hamsters. Moreover, an attempt was made to explain the morphogenesis of these patterns, according to current knowledge on coronary artery development. Eleven affected hamsters belonging to a laboratory inbred family were examined by means of internal casts of the heart, great arterial trunks and coronary arteries. The aortic valve was tricuspid (normal) in seven hamsters and bicuspid in the other four. A rudimentary coronary artery arose from the right side of the aortic valve in four specimens, from the left side of the aortic valve in a further three, and from the dorsal aortic sinus in the remaining four. In all cases, a second, well-developed coronary artery provided for all the coronary blood flow. Except for the existence of a rudimentary coronary artery, the present anomalous coronary artery distribution patterns are similar to coronary artery patterns reported in Syrian hamsters, dogs and humans in association with a solitary coronary ostium in aorta. We suggest that an unusual prolonged time interval in the development of the embryonic coronary stems might be a key factor in the formation of coronary arteries displaying significantly dissimilar developmental degrees.  相似文献   

4.
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5.
A surgically induced model of arterial thrombosis in pigs (60–80 kg live weight) has been developed using a balloon angioplasty technique. The purpose of this model is to assess the thrombogenicity of milkfat in comparison with other dietary lipids, thereby assessing its importance in the pathogenesis of human coronary heart disease. Balloon angioplasty catheters (Meditech, 3 cm X 8 mm balloon) are inserted into the left and right femoral arteries via a cut-down on to the saphenous artery. The balloons are inflated five times for 30 seconds with 30 second intervals between inflations. This results in endothelial denudation, exposure of sub-endothelial connective tissue and formation of platelet rich thrombi. Thrombus size is quantitated using autologous blood platelets labelled with 99Tc-HMPA0 (technetium - “Deretec”).  相似文献   

6.
Little attention is being paid to the presence of accessory coronary artery ostia in man and non-human mammals due to their limited clinical relevance. However, information about their frequency and the cardiac territories irrigated by the vessels arising from them is of interest to obtain an accurate survey of the establishment of the coronary artery system in each species. The aim here was to compare the incidence and significance of the accessory coronary ostia in Syrian hamsters with normal coronary arteries and several coronary anomalies characterized by the absence of a left coronary artery originating from the left aortic sinus. The hearts from 2829 hamsters were examined using a corrosion-cast technique, micro-dissection, histochemical techniques, and scanning electron microscopy. Overall, 148 specimens displayed accessory ostia. A limited number of them belonged to the conal artery which supplies the wall of the right ventricular outflow tract. The other accessory ostia led to the septal artery, a vessel which irrigates the most part of the interventricular septum. The incidence of accessory ostia in normal and anomalous coronary artery patterns was quite similar. This suggests that the morphogenetic deviations producing the coronary artery anomalies reported in this study do not alter the connections of the septal and conal arteries to the aorta. The present observations lead to the notion that in the Syrian hamster, the septal artery should be regarded as a third coronary artery.  相似文献   

7.
Minimal inhibitory concentration (M.I.C.) values as determined by an agar-plate-dilution method for 60 bacterial isolates, consisting of Salmonella typhimurium, Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus of animal origin against 20 antimicrobial drugs are presented. Of all the drugs, gentamicin had the best in vitro antibacterial activity in terms of M.I.C. when considering all the species of organisms together, while spectinomycin had the least activity.

An inoculum replicator was a convenient tool in carrying out the agar-plate-dilution method.

A comparison of the M.I.C. values of 42 isolates of S. typhimurium with the results obtained by low level method and the Bauer-Kir-by method showed that with few exceptions, there is a general agreement.

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8.
The concept that anatomical variations in the coronary artery tree might be influenced by genes is relatively old. However, empirical evidence on the effect of genotype on the coronary morphology is still scarce. In the Syrian hamster, there is a septal coronary artery which arises from the left or from the right coronary artery and supplies most of the interventricular septum. The aim was to decide whether the anatomical origin of the septal artery is subject to inheritance factors. Overall, 483 internal casts of the heart and coronary arteries were examined. All the hamsters included in this study had normal coronary arteries. The results of 74 crosses were compared statistically to seek for any significant difference between the phenotypes of the offspring and the phenotypes of the parents. The left septal artery was over‐represented in the offspring of crosses between parents having both a left septal artery (p < .01), while the right septal artery was over‐represented in the offspring of crosses between parents, one with a right and the other with a left septal artery (p < .001), and, more markedly, in the offspring of crosses between parents both with a right septal artery (p < .001). These results are the first to reveal that the coronary artery pattern is influenced by genetic factors, at least in its proximal portion with regard to the aorta.  相似文献   

9.
Temperature of alfalfa silage was monitored for 28 d at three depths following ensiling in a vacuum bag system. For this silo system, silage was piled on one sheet of plastic and covered by another; the plastic sheets were connected on all sides by rolling and clamping around a polyvinylchloride pipe. The silo was evacuated with a vacuum pump attached to a perforated pipe placed on the bottom sheet of plastic prior to filling. Temperatures increased linearly as depths increased (0.3 to 0.6 and 0.9 m), but temperature measurements were <35.9oC at all depths. Storage cost per ton of silage ensiled was very sensitive to the quantity ensiled and marginally sensitive to DM losses. For a vacuum silo with 40 metric ton (mT) (DM) capacity, storage cost estimates per mT (DM) were $8.90, $9.50, $9.95, and $10.44 for 5, 11, 15 or 19% DM losses, respectively. Temperature differences attributable to post-ensiling days were detected. The performance of 48 midlactation (187+ 45 din milk) cows fed diets based on forages (45.8 to 61.4% DM) of corn (CS), alfalfa, or ryegrass silages (RS) with or without 7.0% cottonseed hulls (CSH) was compared in a 75-d lactation trial. Corn silage was ensiled in an upright silo; alfalfa silage was ensiled in both an Ag-Bag® (Ag-Bag International, Warrenton, OR) and vacuum bag system (BAL and VAL, respectively); RS was ensiled in an Ag-Bag® system. Cows fed CS without CSH produced more milk (21.1 kg/d) than did cows fed the other three silages (17.1 to 19.1 kg/d). No differences in milk production were detected for cows consuming silage from the different ensiling systems, indicating that the vacuum ensiling process can be a satisfactory method of making silage. Cows fed RS consumed less DM (11.0 to 12.1 kg/d) than did cows fed the other three silages (14.4 to 20.4 kg/d). Inclusion of CSH in the alfalfa silage-based diet increased DMI, milk production, and BW gain but had no effect on milk fat or protein percentage. A vacuum silo system may be a satisfactory method of ensiling crops, especially during emergency situations, for short-term ensiling, and for small herds. Systems, Silage, Dairy Cows, Milk Production.)  相似文献   

10.
Saskatchewan, in the summer of 1962, was the scene of an extensive outbreak of western equine encephalomyelitis (WEE) in horses. The results of mosquito survey work showed Culiseta inornata and Culex tarsalis respectively to be the two most abundant mosquito species during midsummer. These species are those reported to be most commonly associated with outbreaks of WEE. Five hundred and sixty-four pools of mosquitoes were examined for the presence of WEE virus. Six pools, three of C. tarsalis and one each of C. inornata, Aedes flavescens and Aedes dorsalis, yielded WEE virus. Positive mosquitoes were from St. Walburg (C. inornata), Saskatoon (C. tarsalis — two, A. dorsalis — one), Outlook (C. tarsalis) and Kisbey (A. flavescens).  相似文献   

11.
A study was undertaken to evaluate the response of different test systems to preparations of heat-stable enterotoxin (ST) derived from Eschericihia coli strains recovered from diarrheal disease of humans, pigs and calves. Sterile broth culture supernatants of enterotoxigenic strains of E. coli were heated at 65°C for 30 minutes and tested for the presence of heat-stable enterotoxin. Three test systems, namely, ligated intestine of weaned pigs, ligated intestine of rabbits and the infant mouse test were used in attempts to detect ST in the culture supernatants. Two patterns of reaction were observed in response to ST-containing preparations: either the preparation elicited a response in the three tests or the preparation elicited a reaction only in the ligated pig intestine. A response in all three tests were observed for 5/5 human ST-producing E. coli, 5/5 bovine enterotoxigenic E. coli, 5/5 “atypical” porcine enterotoxigenic E. coli, 3/3 St+LT- porcine E. coli of serogroup O138:K81 and 4/24 LT+ST+ porcine E. coli. A response only in the ligated pig intestine was obtained with 5/5 ST+LT- porcine E. coli belonging to serogroups other than O138:K81 and to 20/24 ST+LT+ E. coli from pigs. The results are consistent with the view that there are two kinds of ST, one of which (ST1) reacts in all three tests and the other (ST2) which reacts only in the ligated pig intestine. The findings underscore the limitations of the infant mouse test as a means of detecting ST in porcine isolates of E. coli, since the test fails to detect ST produced by a large number of these E. coli strains. There appeared to be a relationship between kind(s) of ST produced and the animal species from which the producing organism was recovered.  相似文献   

12.
Coronary artery anomalies are traditionally classified into anomalies of origin, course and termination. One of the anomalies of origin is absence of the left main coronary artery (LMCA), where the left anterior descending (LAD), the circumflex (Cx) and the ramus medianus (RM) (when present) arteries originate directly from the left aortic sinus. The study aimed to document the prevalence of absent LMCA, discuss its possible embryogenesis and clinical relevance. A review of 407 coronary angiograms performed by cardiologists of three private hospitals in the eThekwini Municipality area of KwaZulu‐Natal, South Africa, was performed. The LMCA was absent in 9.6% (39/407) of the coronary angiograms. The LAD and Cx arteries originated directly from the left aortic sinus with a single ostium in 8.6% (35/407) and separate ostia in 1% (4/407) of the angiograms. In four of the angiograms with absent LMCA, a RM artery was recorded originating directly from the left aortic sinus in addition to the LAD and the Cx arteries. Angiographic detection of the anomalies of the coronary arteries is essential in the determination of the significance of such findings and their management.  相似文献   

13.
A toxin which is lethal for two week old chicks has been recovered from strains of Escherichia coli O78:K80 of bovine and avian origin and from avian isolates of serogroups O2, O45 and O109. The toxin is heat-labile, antigenic, high in protein, inactivated by pronase, trypsin, amylase, and pancreatic lipase. The toxin may be precipitated by ammonium sulfate or TCA treatment from the supernatant obtained by repeated centrifugation of sonicated cells. Considerable purification has been obtained by column chromatography using Sepharose 6B.  相似文献   

14.
Sir, — Andrews’(2) checklist of helminth parasites of wild ruminants in New Zealand recorded the presence of 10 species of gastrointestinal nematodes in chamois (Rupicapra rupicapra rupicapra L.) from “Central South Island”. In October 1978 we examined 28 freshly-shot chamois cadavers from the Harper-Avoca watershed in the headwaters of the Rakaia River. Six of the nematode species reported by Andrews were found again; viz. Ostertagia ostertagi, O. circumcincta, O. trifurcata, Nematodirus filicollis, Oesophagostomum venulosum and Trichuris ovis. The 4 species found by Andrews that were not recovered by us from the animals we examined were: Trichostrongylus axei, T. vitrinus, Spiculotragia spiculoptera and S. asymmetrica. On the other hand we found 4 helminths not encountered by Andrews: 3 nematodes: Nematodirus spathiger (Railliet, 1896), N. abnormalis (May, 1920), and Chabertia ovina (Fabricius, 1794), and 7 specimens of the cestode Moniezia expansa (Rud., 1805). Nematodirus spathiger was the most commonly encountered Nematodirus species, but generally the numbers of all 3 species encountered were low as might be expected in a sample of adult and almost year-old animals. It is probable that most of the adults had acquired some measure of immunity(3), and the most susceptible group, the kids, would not be born until late November. Because peptic digestion was not used to recover juveniles from the intestinal submucosa, only small numbers of adults were obtained.  相似文献   

15.
A 7-year-old male castrated domestic short-haired cat suddenly died. Gross examination revealed severe right-sided haemothorax with blood clots, four adult filarial nematodes in the blood clots and the caudal vena cava and haemorrhage dissecting into the tunica media of the right pulmonary artery. Histopathological investigation showed fibrosis of the tunica intima and disorganization/fragmentation of the elastic fibres accompanied by fibrous tissue deposition in the tunica media of both branches of pulmonary artery. Degenerative vasculopathy (intimal fibromuscular hyperplasia and medial hypertrophy/hyperplasia) involving pulmonary arteries was also observed. The polymerase chain reaction amplification and sequencing confirmed the identification of the parasite as Dirofilaria immitis. A diagnosis of pulmonary artery dissection with haemothorax and concomitant heartworm disease was formulated. Degenerative processes of the tunica media have been reported to cause pulmonary artery dissection in both humans and animals. Pulmonary artery remodelling induced by heartworms may be considered the underlying cause in the first case of feline pulmonary artery dissection, herein described.  相似文献   

16.
A total of 10 adult, healthy, male chinchillas (Chinchilla lanigera) were used to investigate the origin, course, and termination of the coronary arteries. Coloured latex was injected into the carotid arteries following conventional anatomical applications. In all the chinchillas examined, the left coronary artery was the single coronary artery. The right coronary artery was missing. Additionally, a small vessel originating from the cranial border of the aorta was observed in one chinchilla. The left coronary artery divided into the paraconal, interventricular and left circumflex rami. The left marginis ventricular ramus arose from the paraconal interventricular ramus in eight chinchillas, and from the left circumflex ramus in two. The ventricular and septal branches of the left coronary artery ran subepicardially at the beginning mostly parallel to the muscle fibres, also surrounded by a thin adipose tissue. It was concluded that the only left coroner artery supplied blood to the heart in the chinchilla.  相似文献   

17.
Collateral pulmonary circulation was evaluated angiographically 11 months after experimental infection of dogs with either 25 or 100 infective larvae of Dirofilaria immitis. In both groups, collateral pulmonary circulation developed from bronchial arteries and esophageal branches of the left gastric artery. Of the four dogs receiving 25 larvae, one had no detectable collateral circulation, one developed collateral pulmonary circulation from the bronchial arteries only, and two had collateral pulmonary circulation from the bronchial arteries and esophageal branches of the left gastric artery. Of the three dogs receiving 100 larvae, all had collateral pulmonary circulation from the bronchial arteries and the esophageal branches of the left gastric artery. Bronchial artery collateral pulmonary circulation was more extensive in the 100-larvae dogs than in the 25-larvae dogs. Collateral pulmonary circulation from the left gastric artery esophageal branches was similar in both dog groups. Angiographically detectable collateral pulmonary circulation developed within the first year of heaertworm infection. In some respects, the extent of collateral pulmonary circulation development was related to the severity of heartworm infection.  相似文献   

18.
A total of 25 (13 male, 12 female) adult, healthy Swiss albino mice were used to investigate the origin, course and anastomoses of coronary arteries. Coloured latex was injected into the aortic arch to enable these arteries to be clearly discerned. A. coronaria sinistra was larger than A. coronaria dextra. It was divided into a Ramus interventricularis paraconalis and a Ramus circumflexus sinister. However, in 2 specimens, the septal ramus, was observed to stem directly from the left coronary artery, and only 1 ventricular branch arose from the left circumflex. The collateral branches of the paraconal interventricular ramus had a larger diameter and more extensive distribution was observed in these specimens. The A. coronaria dextra was divided into a Ramus septalis and Ramus circumflexus dexter. The Ramus interventricularis subsinuosis was not detected in this study. The ventricular branches of the left coronary artery run intramyocardially whereas the branches of the right coronary artery course subendocardially.  相似文献   

19.
Anomalies involving arterial branches in the lungs are one of the causes of hemoptysis in humans and dogs. Congenital and acquired patterns of bronchoesophageal artery hypertrophy have been reported in humans based on CT characteristics. The purpose of this retrospective study was to describe clinical, echocardiographic, and multidetector computed tomography features of bronchoesophageal artery hypertrophy and systemic‐to‐pulmonary arterial communications in a sample of 14 dogs. Two main vascular patterns were identified in dogs that resembled congenital and acquired conditions reported in humans. Pattern 1 appeared as an aberrant origin of the right bronchoesophageal artery, normal origin of the left one, and enlargement of both the bronchial and esophageal branches that formed a dense network terminating in a pulmonary artery through an orifice. Pattern 2 appeared as a normal origin of both right and left bronchoesophageal arteries, with an enlarged and tortuous course along the bronchi to the periphery of the lung, where they communicated with subsegmental pulmonary arteries. Dogs having Pattern 1 also had paraesophageal and esophageal varices, with the latter being confirmed by videoendoscopy examination. Authors conclude that dogs with Pattern 1 should be differentiated from dogs with other congenital vascular systemic‐to‐pulmonary connections. Dogs having Pattern 2 should be evaluated for underlying pleural or pulmonary diseases. Bronchoesophageal artery hypertrophy can be accompanied by esophageal venous engorgement and should be included in the differential diagnosis for esophageal and paraesophageal varices in dogs.  相似文献   

20.
Sir, — We wish to report the isolation of two potent neurotoxins from herbage collected from pastures on which the disease of livestock known as ldryegrass staggers rd(8)(11) occurred. These neurotoxins have been partially characterised by their mass spectral properties (see below) and appear to be new compounds not previously reported. We propose the general name lolitrems for the neurotoxins, based on their association with ryegrass (Lolium perenne L.) and on their ability to produce tremors in animals, and name the isolated compounds lolitrem A and lolitrem B.  相似文献   

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