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1.
The immunological problems of pig hearts supporting life in human recipients have potentially been solved by transgenic technology. Nevertheless, other problems still remain. Autonomic innervation is important for the control of cardiac dynamics and there is evidence suggesting that some neurons remain intact after transplantation. Previous studies in the human heart have established regional differences in both general autonomic innervation and in its component neural subpopulations. Such studies are lacking in the pig heart. Quantitative immunohistochemical and histochemical techniques were used to demonstrate the pattern of innervation in pig hearts (Sus scrofa). Gradients of immunoreactivity for the general neural marker protein gene product 9.5 were observed both within and between the endocardial, myocardial and epicardial plexuses throughout the 4 cardiac chambers. An extensive ganglionated plexus was observed in the epicardial tissues and, to a lesser extent, in the myocardial tissues. The predominant neural subpopulation displayed acetylcholinesterase activity, throughout the endocardium, myocardium and epicardium. These nerves showed a right to left gradient in density in the endocardial plexus, which was not observed in either the myocardial or epicardial plexuses. A large proportion of nerves in the ganglionated plexus of the atrial epicardial tissues displayed AChE activity, together with their cell bodies. Tyrosine hydroxylase (TH)-immunoreactive nerves were the next most prominent subpopulation throughout the heart. TH-immunoreactive cell bodies were observed in the atrial ganglionated plexuses. Endocardial TH- and NPY-immunoreactive nerves also displayed a right to left gradient in density, whereas in the epicardial tissues they showed a ventricular to atrial gradient. Calcitonin gene-related peptide (CGRP)-immunoreactive nerves were the most abundant peptide-containing subpopulation after those possessing NPY immunoreactivity. They were most abundant in the epicardial tissues of the ventricles. Several important differences were observed between the innervation of the pig heart compared with the human heart. These differences may have implications for the function of donor transgenic pig hearts within human recipients.  相似文献   

2.
The electrical properties of the heart as the generator of the surface electrocardiogram are often described by its multipole moments. While it is possible to ascribe physiological meaning to the dipole moment, the physiological meaning of the higher moments (like quadrupole, octopole, etc.) is not clear. In the following, the multipole moments of the heart at any instant of its depolarization are related to the depolarized portions of the epicardium and endocardium at that time. The surfaces of the heart are divided into elements. Transfer coefficients between the known multipoles and these elements are defined. The transfer coefficients relate the multipoles and the fraction of depolarized area in each element. For the cases reported here, 3 to 8 surface elements are utilized, and the dipole, quadrupole, and octopole moments are studied. The general physiological characteristics of the activation process are formulated as a set of linear constraints. The whole problem is formulated as a quadratic programming problem and it is solved by standard techniques. The first three moments of an idealized human heart, the dipole, the quadrupole, and the octopole (the latter has not yet been measured), are calculated utilizing known experimental data of the activation of the heart. These moments and the activation data are used for testing the proposed procedures of interpreting multipolar data. It is found that from known dipole moments the depolarized fractions of 3 or 4 elements representing the left ventricular endocardium could be calculated. When the quadrupole moments are known, it might be possible to get some information about the activation of the right ventricle as well. These results are not improved by using octopole moments. The constraints used are valid only for the phase of activation of the ventricles. Supported in part by Program Research Grant HL-14388 from the National Heart and Lung Institute.  相似文献   

3.
Immunoglobulin synthesis in primary and myeloma amyloidosis.   总被引:1,自引:0,他引:1  
Bone marrow cells from 14 patients with primary amyloidosis and two patients with myeloma amyloidosis were studied by immunofluorescence and biosynthesis experiments after incorporation of radioactive amino acids. Cells from four patients affected with non-myeloma secondary amyloidosis were also studied as controls. In primary amyloidosis, monoclonal plasma cell populations were demonstrated by immunofluorescence in virtually every case, even in patients without serum and urine monoclonal immunoglobulin and with a normal percentage of bone marrow plasma cells. Biosynthesis experiments showed the secretion of large amounts of free light chains, most often of the lambda type, in every primary or myeloma amyloidosis case and the presence of light chain fragments in almost all cases. Special features in certain patients were the synthesis of short gamma chains (two cases), assembly block at the HL half molecule level of a monoclonal IgA (one case) and secretion of decameric abnormally large kappa chains (one case). This is in contrast with non-myelomatous secondary amyloidosis where the distribution of bone marrow plasma cells was normal by immunofluorescence and where normal sized immunoglobulins were synthesized, without free light chain secretion and fragments. These data confirm that primary amyloidosis belongs to plasma cell dyscrasias and emphasize the role of free light chains and light chain fragments in the pathogenesis of amyloid deposition.  相似文献   

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The endothelial lining (EL) of ventricular endocardium and coronary arteries of a dog, minipig and humans, as well as that of the abdominal aorta of a rat and superior vena cava (minipig) was studied using luminescent microscope in the reflected light after staining of the non-fixed tissue with thioflavine-T and argentation. Marked heterogeneity of the endotheliocytes was shown to be both specific and depending on the localization of the cells in the cardiovascular system. Comparative analysis of EL in different animal species and in man, as well as in different parts of the CVS, indicated the relationship between the cellular morphologic features and local hemodynamics.  相似文献   

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Protein AA, the main fibril constituent in secondary systemic amyloidosis, was demonstrated by the peroxidase-anti-peroxidase method in kidney sections from five out of 14 cases of primary and myeloma associated amyloidosis, all having an immunoglobulin light chain derived protein as a major subunit. In three of these cases, protein AA was also demonstrated in double immunodiffusion of dissolved amyloid preparations. The protein had the characteristics of protein AA in elution position, immunodiffusion and isoelectric focussing pattern. The significance of protein AA in primary and myeloma associated amyloidosis is unknown.  相似文献   

8.
A mouse strain, ICR/SLC, was involved in spontaneous amyloidosis with high incidence. The amyloid deposition in this strain was seen mainly in the mucosal propria of duodenum and terminal ileum, liver, spleen, adrenal cortices, and renal glomeruli. The mice, orally administered more than 300 mg/kg of organic germanium for 22 months since 5 weeks old, did not develop amyloidosis. Half of the mice, given 30 mg/kg of organic germanium for 22 months developed amyloidosis. The mice given 5% carboxymethylcellulose, the solvent of organic germanium, were affected with systemic amyloidosis with high frequency. The results showed that the organic germanium successfully inhibited the occurrence of senile amyloidosis with dose response. The agent did not have any apparent relation to the incidence of hepatic cell carcinoma or pulmonary adenoma which is frequently combined with aged mice. Although the actual mechanism involved is not clear, the evidence of the inhibition of senile amyloidosis by organic germanium may give a light to elucidate the pathogenesis of amyloidosis.  相似文献   

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10.
Summary The present study deals with qualitative und quantitative analysis of osteoclastic bone resorption in metastatic bone disease. 267 cases were examined histomorphologically and divided into three developmental stages. In the first phase of early appearance no bone resorption takes place. The stimulation of osteoclastic resorption in the surroundings of tumour tissue is typical in the second phase of interaction. Pressure atrophy, aseptic necrosis and osteolysis by the tumour cells themselves are other mechanisms of bone destruction in the last phase of carcinomatosis. Because osteoclasts are exclusively responsible for the loss of bone tissue in the phase of interaction, this stage is suited for precise quantitative analysis of osteoclastic resorption. 24 pure osteolytic secondary bone tumours of various primary lesions were examined histomorphometrically. The numerical values were compared with each other and with standard values of healthy individuals. In contrast with normal bone tissue the fractional resorption surfaces und osteoclast indices increase in metastases. Activated osteoclasts are larger and have more nuclei. The numbers of osteoclast index and nuclei per osteoclast are significantly higher in renal than in breast carcinoma. Osteoclasts can be activated in distances of more than 500 µm from tumour tissue. The mean stimulation distance in metastasis from squamous cell carcinoma is markedly higher than in secondary bone tumours of breast carcinoma. Several osteoclast activating substances and divers mechanisms of stimulation might be responsible for different numerical values of morphometric parameters in metastases from various primary malignancies.Dedicated to Prof. Dr. G. Seifert on the occasion of his 65th birthday  相似文献   

11.
The aim of the present study was to compare the distribution of ion currents and the major underlying ion channel proteins in canine and human subepicardial (EPI) and midmyocardial (MID) left-ventricular muscle. Ion currents and action potentials were recorded from canine cardiomyocytes derived from the very superficial EPI and central MID regions of the left ventricle. Amplitude, duration and the maximum velocity of depolarization of the action potential were significantly greater in MID than EPI myocytes, whereas phase-1 repolarization was more pronounced in the EPI cells. Amplitudes of the transient outwards K+ current (29.5±1.5 vs. 19.0±2.3 pA/pF at +50 mV) and the slow component of the delayed rectifier K+ current (10.3±2.3 vs. 6.5±1.0 pA/pF at +50 mV) were significantly larger in EPI than in MID myocytes under whole-cell voltage-clamp conditions. The densities of the inwards rectifier K+ current, rapid delayed rectifier K+ current and L-type Ca2+ current were similar in both cell types. Expression of channel proteins in both canine and human ventricular myocardium was determined by Western blotting. In the canine heart, the expression of Kv4.3, Kv1.4, KChIP2 and KvLQT1 was significantly higher, and that of Nav1.5 and MinK much lower, in EPI than in MID. No significant EPI-MID differences were observed in the expression of the other channel proteins studied (Kir2.1, 1C, HERG and MiRP1). Similar results were obtained in human hearts, although the HERG was more abundant in the EPI than in the MID layer. In the canine heart, the EPI-MID differences in ion current densities were proportional to differences in channel protein expression. Except for the density of HERG, the pattern of EPI-MID distribution of ion-channel proteins was identical in canine and human ventricles.  相似文献   

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Postmortem findings in primary familial amyloidosis with polyneuropathy.   总被引:5,自引:0,他引:5  
The pathology of primary familia amyloidosis with polyneuropathy is described on the basis of post-mortem examination of six cases from Northern Sweden. Clinically the disease is characterized by progressive sensory and motor disturbances with loss of sensation, muscular wasting and flaccid paralysis. Impotence, urinary bladder dysfunction, motility disturbances of the gastro-intestinal tract and postural hypotension indicate affection of the autonomic nervous system as well. Malabsorption, cardiac insufficiency and vitreous opacites also occur. As regards the distribution of amyloid, the following findings seemed to be characteristic. Usually there were no gross lesions indicating the amyloid disease. Histopathologically, amyloid deposits were observed in great extent in the peripheral nervous system and in various parts of the peripheral autonomic nervous system as well. It occurred extensively in the walls of blood vessels of various calibres, in the perivascular collagenous connective tissue and adjacent to the smooth musculature. Amyloid deposition was also found more or less abundantly in various other organs and tissues. No deposits, however, or only insignificant amounts, were found in the central nervous system, either in the parenchyma of the liver, in the islets of Langerhans, or in the bone marrow. Clinical manifestations seemed to be related to the local deposition of the amyloid substance. Our clinical and pathological findings in this particular type of familial amyloidosis conformed mostly to those previously described.  相似文献   

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15.
Amyloid deposits were found subepithelially in the seminal vesicles of 34 of 209 consecutively studied men. The incidence increased with age and was found in 21% of men over 75 years. This senile seminal vesicle amyloidosis (SSVA) is a localized disorder, and the amyloid substance has unique histochemical and immunochemical properties not shared with any other amyloid described until now.  相似文献   

16.
The morphologic changes in trabecular bone were studied in 60 patients with surgically proven hyperparathyroidism and in 69 patients with nephrolithiasis. The hyperparathyroid bone lesions showed substantial variation in their extent. Four, typical stages were defined. The structure of trabecular bone remained intact in most cases. Bone turnover is significantly higher in the patients with primary hyperparathyroidism. Fifty percent of all patients with nephrolithiasis had bone changes similar to those found in the surgically proven hyperparathyroidism group. In 50% of so-called asymptomatic cases of hyperparathyroidism, the iliac crest biopsy is a useful supplement to clinical and hormonal data in deciding whether to operate on the parathyroid glands. In about 45% of cases, however, no definite diagnoses is possible. The determination of serum parathyroid hormone in primary hyperparathyroidism has a greater importance for diagnostic purposes than morphologic investigation of the bone biopsy.  相似文献   

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The liver is a major site of amyloid deposition. The spectrum of histopathologic changes in the liver was studied in 38 patients with systemic amyloidosis (25 with primary or myeloma-associated amyloidosis [AL] and 13 with secondary, reactive [AA] amyloidosis). Overall architectural distortion, alterations of portal triads, as well as predilection for topographic deposition in the parenchyma and/or blood vessel walls were noted. Significant histopathologic differences in AL or AA amyloid liver involvement included 1) portal fibrosis, seen in 7 of 25 (28%) AL patients and 8 of 13 (62%) AA patients (P = 0.05), 2) parenchymal amyloid deposition in 25 of 25 (100%) AL amyloid and 10 of 13 (77%) AA amyloid patients (P = 0.04), and 3) vascular amyloid deposition found in 17 of 25 (68%) with AL amyloid and 13 of 13 (100%) patients with AA amyloid (P = 0.02). These data vary from the widely held concept that deposition of amyloid is predominantly vascular in the AL form and parenchymal in amyloid AA. Clearly, however, in individual cases significant overlap occurred, and characterization of amyloid types based on morphologic distribution of amyloid deposits may be possible in only a minority of cases. In most cases, differentiation of amyloid AL and amyloid AA forms requires clinical, histochemical, immunochemical, and sometimes more elaborate laboratory amino acid sequence studies for accurate identification.  相似文献   

19.
A simple mathematical model of the intramyocardial circulation has been utilized to provide a better understanding of coronary blood flow. The model includes three myocardial layers, each characterized by a three-parameter windkessel with one capacitance and two resistances. The effects of the beating heart are taken into account by means of an intramyocardial pump and the possible collapse of the vessels by an elevated backpressure. The three basic parameters that govern the flow are a normalized time constant, , the total resistance, Rt, and a parameter, α, which specifies the resistance distribution in the intramyocardial circulation. Both the normal beating heart and prolonged diastole have been investigated analytically as well as numerically. It is shown that each of these parameters has its own special significance. Calculated pressure-flow relationships and zero-flow pressures for the case of prolonged diastole show a high sensitivity to and α.  相似文献   

20.
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