Morphologic study of left ventricular bands

The presence of left ventricular bands has drawn attention to their possible clinical importance, though there are no concrete data to support their role in serious clinical diseases. We have investigated the incidence, location, microscopic and macroscopic structure of left ventricular bands in the human and animals. We examined 100 hearts: 28 human and 72 animal (dog, goat, sheep). Left ventricular bands were present in 13 of 28 (46%) human hearts and 62 of 72 (86%) animal hearts. The bands usually extended from the interventricular septum to the free walls in human hearts and from the papillary muscles to the interventricular septum in animal hearts. They were composed of muscle tissue in various proportions in human and dog hearts, and of connective and conductive tissue in sheep and goat hearts.     

羊心左冠状动脉形态学观察

目的　探讨羊心脏左冠状动脉的解剖结构 ,丰富动物实验资料。方法　局解手术学实验后处死山羊 ,取羊心 90例 ,经 10 %甲醛固定 ,手工剥制显示左冠状动脉 ,6例用过氯乙烯 乙酸乙脂填充剂注入冠状动脉中制成动脉血管铸型 ,测量左冠状动脉及其分支。结果　羊冠状动脉分左、右冠状动脉 ,左冠状动脉粗大较浅表 ,前降支行于心肌表面或深达心肌不能明视 ,上多附有心肌桥 ,旋支粗大行程长分支多 ,二者之间多有对角支出现。羊心冠状动脉为左优势性。结论　羊冠状动脉与人相比有较大差异     

Intramural Purkinje Cell Network of Sheep Ventricles as the Terminal Pathway of Conduction System

To identify the anatomical basis for cardiac electrical signal conduction, particularly seeking the intramural terminals of conduction pathway within the ventricles, sheep hearts were examined compared with human hearts utilizing the characteristic morphology of Purkinje cells as a histological marker. In 15 sheep and five human autopsies of noncardiac death, prevalence of Purkinje or Purkinje‐type cells were histologically examined in the atrioventricular node, its distal conduction pathway, the interventricular septum, and the right‐ and left‐ventricular free walls. Myocardial tissue cleavages were examined in the transmural sections (along cardiac base‐to‐apex axis) obtained from the septum and ventricular free walls. Serial histological sections through virtually the entirety of the septum in selected sheep were used as the basis of a three‐dimensional reconstruction of the conduction pathway, particularly of the intramural Purkinje cell network. Purkinje cells were found within the mural myocardium of sheep ventricles whereas no intramural Purkinje‐type cell was detected within the human ventricles. In the sheep septum, every intramural Purkinje cell composed a three‐dimensional network throughout the mural myocardium, which proximally connected to the subendocardial extension of the bundle branches and distally formed an occasional junction with ordinary working myocytes. The Purkinje‐cell network may participate in the ventricular excitation as the terminal conduction pathway. Individual connections among the Purkinje cells contain the links of through‐wall orientation which would benefit the signal conduction crossing the architectural barriers by cleavages in sheep hearts. The myocardial architectural changes found in diseased hearts could disrupt the network links including those with transmural orientation. Anat Rec, 2009. © 2008 Wiley‐Liss, Inc.     

Comparison of myocardial infarction with sequential ligation of the left anterior descending artery and its diagonal branch in dogs and sheep

We report a comparison of the effects of myocardial infarction in dogs and sheep using sequential ligation of the left anterior descending artery (LAD) and its diagonal branch (DA), with hemodynamic, ultrasonographic and pathological evaluations. Five animals were used in each group. After surgical preparation, the LAD was ligated at a point approximately 40% of the distance from the apex to the base of the heart, and after one hour, the DA was ligated at the same level. Hemodynamic and ultrasonographic measurements were performed preligation, 30 minutes after LAD ligation, and 1 hour after DA ligation. As a control, two animals in each group were used for the simultaneous ligation of the LAD and the DA. Two months after the coronary ligation, the animals were evaluated as previously, and killed for postmortem examination of their hearts. All seven animals in the dog group survived the experimental procedures, while in the sheep group only animals with sequential ligation of the LAD and DA survived. Statistically significant decreases in systemic arterial blood pressure and cardiac output, and an increase in the pulmonary artery capillary wedge pressure (PACWP) were observed one hour after sequential ligation of the LAD and its DA in the sheep, while only systemic arterial pressures decreased in the dog. Ultrasonographic analyses demonstrated variable degrees of anteroseptal dyskinesia and akinesia in all sheep, but in no dogs. Data two months after coronary artery ligation showed significant increases in central venous pressure, pulmonary artery pressure, and PACWP in the sheep, but not in the dog. Left ventricular end-diastolic dimension and left ventricular end-systolic dimension in ultrasonographic studies were also increased only in the sheep. Pathologically, the well-demarcated thin-walled transmural anteroseptal infarcts with chamber enlargement were clearly seen in all specimens of sheep, and only-mild-to-moderate chamber enlargements with endocardial fibrosis were observed in the dog hearts. In conclusion, this study confirms that the dog is not a suitable model for myocardial infarction with failure by coronary artery ligation despite negligent operative mortality, when compared directly with an ovine model.     

Feeding patterns of Culex quinquefasciatus (Diptera: Culicidae) from eastern Santa Catarina state, Brazil

Blood-feeding sources of Culex quinquefasciatus Say (Diptera: Culicidae) collected in the eastern region of the Brazilian state of Santa Catarina were analyzed by precipitin technique. One hundred fifty-four female mosquitoes collected by CDC traps in the Navegantes municipality 13-15 February 2005 reacted to one or more of eight antisera, including chicken, dog, goat, sheep, horse, opossum, human and rodent antisera. One hundred thirty-seven specimens (89%) reacted to only one source, and 17 (11%) specimens reacted to two sources. Among the 137 specimens reacting to only one source, reactions to rodent (50.4%), sheep (5.8%), chicken (5.1%), goat (5.1%), dog (2.2%), horse (3.6%), and human (3.6%) antisera were observed. The analyzed species demonstrated a high degree of opportunistic feeding behavior in relation to host preference. Results are compared with results from similar studies, and the low proportion of reactions to human antisera is discussed.     

ANGIOGRAPHIC DIFFERENCE IN CORONARY ARTERY OF MAN, DOG, PIG, and MONKEY

Comparative morphological studies on the coronary arteries of the left ventricular free wall were carried out on human, dog, pig, and monkey hearts by using postmortem coronary arteriography, soft X-ray photograms, and the clearing method. The results showed that the types of coronary arteries (types I, II, and HI) and connecting portion of anastomotic vessels in the pig and monkey hearts closely resembled those in man. Whereas the dog hearts showed the following characteristics: 1) numerous Type III vessels and anastomoses in the epicardial layer, 2) the existence of only the left predominant type of coronary artery, and 3) the supply of blood to the papillary muscles of the left ventricle mostly through a single branch of the coronary artery. Therefore, it is necessary to take into consideration the basic difference in the structure of the coronary arteries of human and dog hearts, when dogs are used experimentally for research of human ischemic heart disease. The fact that only the papillary muscles of the human heart-compared to animal hearts-are supplied blood from two sources may be advantageous to rescue the papillary muscles from ischemic necrosis.     

Angiographic difference in coronary artery of man, dog, pig, and monkey

Comparative morphological studies on the coronary arteries of the left ventricular free wall were carried out on human, dog, pig, and monkey hearts by using postmortem coronary arteriography, soft X-ray photograms, and the clearing method. The results showed that the types of coronary arteries (types I, II, and III) and connecting portion of anastomotic vessels in the pig and monkey hearts closely resembled those in man. Whereas the dog hearts showed the following characteristics: numerous Type III vessels and anastomoses in the epicardial layer, the existence of only the left predominant type of coronary artery, and the supply of blood to the papillary muscles of the left ventricle mostly through a single branch of the coronary artery. Therefore, it is necessary to take into consideration the basic difference in the structure of the coronary arteries of human and dog hearts, when dogs are used experimentally for research of human ischemic heart disease. The fact that only the papillary muscles of the human heart-compared to animal hearts-are supplied blood from two sources may be advantageous to rescue the papillary muscles from ischemic necrosis.     

Osteoarthritis in two marine mammals and 22 land mammals: learning from skeletal remains

The occurrence of osteoarthritis (OA) in marine mammals is still questionable. Here we investigated the prevalence of OA in marine (dolphin and dugong) and terrestrial mammals (Asian elephant, Asiatic buffalo, camel, cat, cattle, deer, dog, domestic goat, horse, human, hyena, impala, lion, Malayan tapir, Assam macaque, mule, pig, rabbit, red kangaroo, sheep, tiger and waterbuck). Skeletal remains obtained from five institutes were used as subjects; a total of 45 different parts (locations) of bones were observed for OA lesions. The prevalence of OA was reported as number of OA lesions/total number of bones. Our results revealed that the presence of OA in marine species (dolphin and dugong) was 2.44% and 3.33%, respectively. In dolphins, the highest OA occurrence was on the left and right humeral trochlea, with 13.68% and 12.63%, respectively, while the highest number of OA lesions in dugongs was on the lumbar vertebrae (8.79%). No significant difference (P > 0.05) in the prevalence of OA between sexes in dolphins and dugongs was observed, but we found a significant difference (P < 0.05) in 24 bone locations of human bones, which had the highest OA prevalence (48.93%), followed by dogs (3.94%). In conclusion, OA can occur in marine mammals, similar to terrestrial mammals, even though their natural habitat is the ocean.     

A Functional Comparison of Animal Anterior Cruciate Ligament Models to the Human Anterior Cruciate Ligament

Many investigators have used animal models to clarify the role of the human anterior cruciate ligament (ACL). Because none of these models are anatomically and biomechanically identical to the human ACL, there exists a need for an objective comparison of these models. To do this, we used a universal force-moment sensor to measure and compare the in situ forces, including magnitude and direction, of the ACL and the anteromedial (AM) and posterolateral (PL) bundles of human, pig, goat, and sheep knees. An Instron was used to apply 50 and 100 N anterior tibial loads at 90° of knee flexion, while a universal force-moment sensor was used to measure the forces applied by the ACL to the tibia, the in situ force of the ACL. We found significant differences between the magnitude of force experienced by the goat and sheep ACL and AM and PL bundles when compared with the human ACL and AM and PL bundles. Also, the direction of the in situ force in the ACL and AM bundles of the goat and sheep were different from the human. The pig knee differed from the human only in the magnitude and direction of the in situ force in the PL bundle in response under anterior tibial loading. A tally of the significant differences between the animal models and the human knees indicates that goat and sheep knees may have limitations in modeling the human ACL, while the pig knee may be the preferred model for experimental studies.     

Sonomicrometric studies on the effects of long-term pumping of cardiac assist device on the bulk and regional mechanics of the normal left ventricle in goat.

Pneumatically driven, diaphragm type left ventricular assist devices (LVADs) were implanted into 2 goats with normal hearts for approximately 1 month to study the effects of long-term pumping of LVAD on the cardiac mechanics. One sham-operated goat was used to obtain control data. Diameters and myocardial segment lengths of the left ventricle were measured with an ultrasonic displacement meter to calculate the bulk mechanical work (BMW) and regional myocardial mechanical work (RMW), respectively. The LVAD was pumped in the 2:1 drive mode (one counterpulsated pumping in every two cardiac cycles), and was temporarily driven in the 1:1 mode (one pumping in every cardiac cycle) or stopped to obtain the data under these conditions. During the second half of the post-operative period while the animal condition was stable, the BMW in the 2:1 and 1:1 modes were approximately 59% and 72% of that observed under the temporary pump-off condition (0.22 W/(100 g)), respectively. The RMW in the 2:1 and 1:1 modes were 69% and 74% of that obtained during pump-off (6.2 mW/cm3), respectively. The myocyte diameter in the subendocardial layer was reduced by unloading effect of 1-month pumping, whereas those in middle and subepicardial layer showed little change.     

山羊心脏中心纤维体内的骨髓组织

目的 探讨山羊心脏中心纤维体的组织结构。方法 用石蜡切片,ＨＥ、Ｍａｓｓｏｎ和苏木素－美蓝－天青－伊红染色,光镜观察。结果 山羊中心纤维体为骨组织,其中有骨小梁和典型的骨髓组织。结论 山羊中心纤维体可能具有造血功能。     

Complement activity in serum and Mg2+-EGTA plasma from various animals for two haemolytic indicator systems

Sheep antibody-sensitized human erythrocytes (SAHE) were haemolyzed by sheep, goat, cow, pig, guinea-pig (g-p), rat, hamster, horse, cat, dog, chicken, mouse, rabbit and human serum. Mg²⁺-ethyleneglycoltetraacetic acid (EGTA) plasma from these species, titrated in the presence of Mg²⁺-EGTA, were also haemolytic. Preserved g-p serum was non-haemolytic for SAHE. All serum samples haemolyzed rabbit antibody-sensitized sheep erythrocytes (RASE) but most of the plasma samples did not. Serum and plasma from many species haemolyzed human and sheep erythrocytes per se.Except for fresh g-p plasma, all plasmas heated at 50°C for 30 min failed to haemolyze SAHE. A CM-cellulose fraction of foetal lamb serum restored haemolytic activity to sheep, goat, cow, pig, horse, cat, dog and chicken plasma in the presence of Mg²⁺-EGTA.These results indicate that an alternative pathway-like mechanism appears to be involved in haemolysis of SAHE by plasma in the presence of Mg²⁺-EGTA.     

Recombinant fusion proteins of protein A and protein G with glutathione S-transferase as reporter molecules

The regions encoding the IgG-binding domains of protein A (PA) and protein G (PG) were cloned into the bacterial expression vector pGEX. Both proteins were expressed in Escherichia coli as fusion proteins with glutathione S-transferase (PA-GST and PG-GST) and were found to be soluble, abundant and easily purified in one step from the bacterial lysate by affinity chromatography on immobilized glutathione. Yields of 50 mg/litre of cultures were obtained. Both purified fusion proteins were shown to be functional in a variety of immunochemical procedures. In radial diffusion tests, PA-GST precipitated IgG from human, squirrel monkey, rabbit, dog, cat and pig but not mouse, sheep, goat, cow, horse or chicken. PG-GST formed precipitin bands with IgG from human, rabbit, mouse, pig, sheep, goat, cow and horse but not squirrel monkey, dog, cat and chicken IgG. The fusion proteins were shown to function as effective detection reagents in ELISA and Western blotting. Glutathione agarose beads with bound fusion protein were shown to be useful for immunoprecipitation.     

Incidence and distribution of isolated atrial amyloid: Histologic and immunohistochemical studies of 100 aging hearts

The incidence and anatomic distribution of isolated atrial amyloid (IAA) in 100 aging hearts were studied histologically and immunohistochemically using antibodies against α-human-atrial natriuretic peptide (α-ANP), human transthyre-tin (TTR) and human amyloid P component (AP). Ninety-one of 100 hearts (91%) had amyloid deposits in the atria. Amyloid deposits in all 91 hearts reacted with α-ANP and AP antisera, and in four hearts other amyloid deposits that reacted with lTR antiserum were coincidentally seen in the atria. The prevalence of IAA deposition, using a semiquantitative evaluation, was significantly higher in the hearts from patients over 80 years of age, from women, those weighing over 450g, with a thickened left ventricular wall (>1.4 cm) and with multiple myocardial scars. IAA deposition showed a significant distribution in the auricle and left atrium; it was located mostly in the interstitium of the subendocardial layer and the subendorcardial myocardium. These results indicate that IAA occurs more frequently than previously appreciated in the elderly and in patients with certain cardiac disorders.     

Prevalence of non-A,non-B hepatitis/hepatitis C virus antibody in human immunoglobulins.

Human intravenous immunoglobulins prepared by the cold ethanol fractionation technique of Cohn are considered safe with respect to infectivity. However, there have been several instances of transmission of both hepatitis B and non-A,non-B hepatitis viruses after administration of intravenous immunoglobulins. To determine the prevalence of hepatitis C virus antibody in intravenous immunoglobulins and protein preparations, 30 commercially available products were tested. Using the Abbott enzyme immunoassay for hepatitis C virus antibody, 27 of 30 (90%) immunoglobulins tested positive. The Ortho immunoassay showed that 28 of 30 (93%) were positive, with one discordant result between the Ortho and Abbott assays. An antigen-blocking or neutralization test (Abbott) confirmed the results of the Ortho assay. Bovine, sheep, goat, and horse sera also were tested before and after isolation of animal immunoglobulins. All results on the animal sera were negative, indicating that the fractionation process did not produce false-positive results. The high prevalence rate of hepatitis C virus antibody in intravenous immunoglobulins has important implications for follow-up of recipients, selection of serum donors, and implementation of anti-hepatitis C virus testing.     

山羊和家猪冠状窦和Marshall静脉肌桥的解剖学特征

目的：报道山羊和家猪心脏冠状窦和Marshall静脉肌桥的形态特征。方法：用大体解剖方法，观测山羊和家猪冠状窦和Marshall静脉肌桥的形态，起止点、走行及出现率，结果：两种动物冠状窦和Marshall静脉肌桥的出现率大于90%，其形态可分环形、纵形和斜形3种，它们均来源于右心房后壁，止于左心房。结论：山羊和家猪冠状窦和Marshall静脉表面覆盖有心肌纤维，是左右心房的异常通道之一这两种动物具备制作局灶性心房颤动物模型的解剖学基础。     

Detection of Breda virus antigen and antibody in humans and animals by enzyme immunoassay.

Enzyme immunoassays were developed for the detection of Breda virus antibody and antigen. Cattle sera collected in the United Kingdom were found to have a high prevalence of antibody (55%) to Breda virus when examined in a competitive enzyme-linked immunosorbent assay. A low prevalence of antibody was found in pigs (2.2%), and no antibody was found in sheep or goat sera. No antibody to either Breda virus or Berne virus was detected in human sera collected from veterinarians and farm workers. Only 1 of 430 human fecal specimens (0.2%) contained Breda virus antigen detectable by enzyme-linked immunosorbent assay.     

Functional, morphological and metabolic characteristics of isolated hearts from normotensive and spontaneously hypertensive rats before, during and after renal hypertension

It has been much discussed whether left ventricular hypertrophy (LVH) in hypertension implies improved or impaired cardiac performance, mainly because experiments in various hypertensive models have given controversial results. It has, for example, been suggested that increased collagen content may depress LV function both in renal and spontaneous hypertension (SHR) in rats. For such reasons cardiac performance was studied both in SHR and in normotensive control rats (NCR) before and during superimposed two-kidney, one clip Goldblatt hypertension, and also 1 week after reversal of hypertension by unclipping. The LV function of the isolated hearts was determined in an antegrade working heart perfusion system. Further, myocardial morphology, with regard to fibrous tissue infiltration and energy metabolic status, were evaluated in the renal hypertensive rats before and after unclipping. Compared with NCR, maximal cardiac performance was elevated in the hypertrophied SHR hearts, but depressed when renal hypertension was superimposed, even though this led to further LVH. However, one week after reversal of renal hypertension, when LVH was still considerable, cardiac function was increased well above the control level, even though the stores of high energy compounds and the content of myocardial fibrous tissue was almost the same as during renal hypertension. It is concluded that LVH generally enhances cardiac performance, but that concomitant renal hypertension exerts a cardio-depressive influence which can neither be ascribed to an increased fibrous tissue content nor to a reduced energy charge potential. It is therefore suggested that some negative inotropic agent of renal or extrarenal origin is released during two-kidney, one clip renal hypertension, which offsets the enhanced performance induced by the left ventricular hypertrophy.     

Anatomy and clinical significance of ventricular Thebesian veins

An injection study was carried out in sheep hearts to compare the anatomy and distribution of Thebesian veins (venae cordis minimae) in the ventricles. The left azygos, middle cardiac, small cardiac, and anterior cardiac veins were ligated in 36 hearts, and India ink was injected into the right coronary artery or the left coronary artery or the coronary sinus. Examination revealed foramina Thebesii in both of these cardiac chambers. Myocardial tissue samples were taken, and 12 were subsequently studied histologically to confirm the presence of Thebesian veins. A greater number of Thebesian veins were observed in the right ventricle than in the left (P < 0.05). To identify any larger communications between the coronary arteries and cardiac chambers (arterioluminal), and between the coronary veins and cardiac chambers (venoluminal), gelatine was injected in 16 hearts. Arterioluminal vessels were identified only in the right ventricle, whereas venoluminal vessels were present in both ventricles. Venoluminal vessels are most likely responsible for the non-nutritive shunting of cardioplegic solutions delivered via the coronary sinus during surgery. Thebesian veins play a role in the drainage of blood, contributing towards right to left shunting of deoxygenated blood. It has also been suggested, although not proven, that they are able to supply blood to the myocardium in coronary arterial occlusion, thus acting as a natural form of nutrient channel. Thebesian veins may be confused with artificial nutrient channels constructed by transmyocardial laser revascularization, a possibility that should be considered during histological evaluation of this technique. Copyright Wiley-Liss, Inc.