Homologous Tissue Research Articles

Cardiac metabolism in high performance fish

Abstract In aerobic tissues, such as cardiac and skeletal muscle, short term increases in energy demand are met primarily by acute regulation of mitochondrial pathways. Chronic increases in time-average metabolic rate of an individual or tissue can lead to modest “physiological adaptations” that may result in increased metabolic capacities and more efficient energy production and utilization. These physiological adaptations differ fundamentally from those which alter metabolic rate acutely. Analysis of the metabolic strategies used by an individual to chronically elevate cardiac metabolic rates may help identify the components of cardiac metabolism which may be constrained or malleable over evolutionary time. While pronounced physiological differences in cardiac energy transduction are apparent across species, the evolutionary origins of such differences are difficult to assess. However, the functional consequences of such differences in homologous tissues across species can be discussed with more certainty. Both chronic hypermetabolic challenges and interspecies comparisons suggest highly oxidative tissues such as heart are restricted to strategies which a) elevate the functional mass b) make more efficient use of intracellular space devoted to mitochondria and c) shift toward more efficient metabolic fuels, primarily fatty acids if oxygen delivery is not a factor.

Analysis of the normal human IgG antibody repertoire. Evidence that IgG autoantibodies of healthy adults recognize a limited and conserved set of protein antigens in homologous tissues.

We have used a quantitative immunoblot technique to analyze the Ab repertoire of IgG in the serum of healthy adults with a large panel of homologous and foreign Ags in tissue extracts. Densitometric patterns of reactivity of purified IgG with self-Ags exhibited striking homogeneity among individuals with regard to the protein bands that were recognized. Purified IgG showed higher levels of reactivity with self-Ags than IgG in whole serum. Reactivity with self-Ags of IgG in whole serum was restricted to a small number of protein bands (fewer than 10). There were significant inter-individual differences in the intensity and nature of immunoreactivities. Purified IgG of different individuals exhibited heterogeneous patterns of immunoreactivity with Ags in bacterial extracts. Comparative analysis of repertoires of IgG and IgM indicated that all protein Ags recognized by IgM were also reactive with purified IgG. Some proteins in homologous and in foreign tissue extracts reacted solely with IgG. Our observations provide direct evidence for the restricted and conserved character of the antiself-repertoire of IgG of healthy adults and suggest that natural IgG Ab repertoires in serum are specifically selected for reactivity with a limited set of self-Ags. In addition, IgG autoreactivity in whole serum is controlled by non-IgG factors that determine the unique reactivity pattern of each individual.

Immunomodulation of fat deposition

Abstract Consumer concern about health together with resistance to the use of exogenous substances in meat production has increased the importance of developing ‘friendly’ methods to increase the lean content of meat. Immunological methods may be more consumer acceptable. One such approach is to directly lyse adipocytes by administration or production of antibodies to adipose tissue plasma membrane proteins. To date, antibodies have been raised to rat, rabbit, chicken, ovine and porcine adipose tissue by active immunisation of other species and their effect on adipose tissue accretion examined in the target species. Such treatment decreased body fat in rats by up to 30%, in rabbits by 17% and in sheep by up to 15%, and decreased backfat thickness by 30% and loin fat by 25% in pigs. There was no effect on fat deposition in poultry. The effects appear to be adipose tissue site specific, to reflect decreases in cell size and number and to be influenced by the age of the animal when immunised and the interval between immunisation and slaughter. Antibodies have been successfully raised by active immunisation with homologous adipose tissue preparations but the effects on fat deposition were less than those observed for the passive approach. Future developments of this technology require the identification of specific antigenic determinants from individual adipose tissue sites. Their use as antigens, when coupled to an immunogenic protein and/or the use of polyclonal or monoclonal antibodies derived from these antigens could lead to commercially important improvements in the efficiency of lean meat production without adverse effects on animal welfare or meat quality.

The anatomy and chemical composition of adipose tissue in wild wolverines(Gulo gulo)in northern Canada

Adipose tissue was dissected completely from 25 adult male and five adult female wolverines shot between October and March, 1990–1992 in Northwest Territories, Canada. The gross mass, mean adipocyte volume, lipid, protein and collagen contents were measured in adipose tissue from 13 superficial and internal depots homologous to those of other terrestrial mammals. The total adipocyte complement was calculated from the mass of each depot and its site‐specific adipocyte volume. Almost all the adipose depots found in other terrestrial mammals were present in wolverines and site‐specific differences in adipocyte volume were similar to those of other species. No significant sex differences were detected. All depots except the cardiac adipose tissue enlarged with increasing fatness, but the superficial depots expanded faster than any of the internal depots and the posterior superficial depots enlarged slightly faster than the anterior depots. The partitioning of adipose tissue between superficial and intra‐abdominal depots, and between anterior and posterior superficial depots, changed with fatness and was consistent with predictions from allometric equations derived from data from other Carnivora. The total adipocyte complement was variable, with more than 70% of the specimens having 2–5 times as many adipocytes as predicted from allometric equations relating adipocyte complement to body mass in other carnivorous mammals. Consequently, the correlation between mean adipocyte volume and total dissectible adipose tissue was weak. Measurements of adipocyte volume from biopsies of adipose tissue, and indices based upon the mass of thickness of one or a few depots, would therefore not provide an accurate estimate of fatness. The concentration of collagen was higher in the superficial and intra‐abdominal adipose depots of specimens collected in mid‐winter than in homologous tissues of those killed in early winter, but there were no comparable seasonal changes in the abundance of lipid or non‐collagen protein.

Use of Vicryl (polyglactin-910) mesh implant for repair of orbital floor fracture causing diplopia: a study of 28 patients over 5 years.

Over the past 5 years, Vicryl mesh (polyglactin-910) implants were used successfully to reconstruct the orbital floor in 28 patients with significant preoperative diplopia due to orbital floor fractures. The layered mesh is available in 26.5 x 24 cm sheets, each of which is folded onto itself into 24 layers and packaged; 24 layers are approximately 4 mm thick. Appropriately sized implants varying in thickness from 6 to 56 layers were used to cover and fill the orbital floor defect. Absorbable Vicryl mesh is well-tolerated by orbital tissues; since it is soft and pliable, it is unlikely to compress orbital structures such as the optic nerve, lacrimal sac, or extraocular muscles. A second surgical site necessary for autogenous implants is avoided. The Vicryl mesh implant is technically easy to insert and does not require fixation in the orbit. Because Vicryl mesh is absorbable, the risks associated with permanent alloplastic implants are reduced. Similarly, there is no potential spread of communicable disease with homologous tissue implants. Follow-up ranged from 1 month to 2 years (median, 13 months). None of the patients had late complications. The only complication was transient, low-grade eyelid inflammation in four patients.

Ontogeny and structure of the drupe of Ozoroa paniculosa (Anacardiaceae)

An exocarp sensu stricto develops from the outer epidermis of the ovary wall. At maturity it comprises extensively radially elongated palisade-like parenchyma cells. Besides having an outer cuticle, the outer tangential and outer parts of the radial cell walls of these cells are strongly cutinized. Large, permanently open stomata and saucer-shaped depressions also characterize the exocarp. The mature mesocarp sensu stricto consists of secondarily thickened parenchyma and brachysclereids. An abundance of tanniniferous deposits and crystals, as well as secretory ducts associated with the vascular bundles also form part of the mature mesocarp. Derivatives of the inner epidermis of the ovary wall differentiate into the stratified endocarp sensu stricto . At maturity this comprises consecutive layers of macrosclercids, osteosclereids (typified by a capirate part and cell wall flutes), brachysclereids, and crystalliferous sclereids. Pericarp structure is related to its taxonomic significance and the possible role of micromorphological characters in the survival strategy of Ozoroa paniculosa. It is shown that ontogenetic studies contribute to the precise interpretation of previously described cell layers, ensuring that homologous tissues are compared in different taxa.

Influence of web-monitoring tactics on the density of mitochondria in leg muscles of the spider family uloboridae.

From electron micrographs we determined the ratio of mitochondrial to myofibril cross sectional area in cells of the first leg anterior depressor muscles of adult females of four spider species, each from a different genus. Species with more active web-monitoring tactics and greater tracheal supplies to their first legs have muscle cells that are better supplied with mitochondria than those with less active tactics and less well-developed tracheal systems. These results demonstrate that, even in homologous tissues of closely related species, mitochondrial supply can change to accommodate changes in metabolic activity. © 1992 Wiley-Liss, Inc.

The Classic

Alexis Carrel (Fig. 1) was born near Lyon, France, in 1873. He received his medical education and surgical training at the University of Lyon and the hospitals in Lyon. From the very beginning, he became interested in experimental surgery. He published his first paper on blood vessel suturing in 1902. In 1904, he came to the University of Chicago to work in the Department of Physiology. In Chicago, in collaboration with C. C. Guthrie, he perfected on experimental animals the techniques of vascular anastomosis, both arterial and venous. In 1906, Carrel moved to the Rockefeller Institute for Medical Research in New York to head the Laboratory of Experimental Surgery. He remained there until his retirement in 1939. There he continued his experiments with transplantation of organs that included transplantation of limbs. In 1914. he stated: “During the last few years it has been definitely established that autoplastic transplantation of organs are practically always successful: that homoplastic transplantation, although the immediate results may be excellent, are nearly always ultimately unsuccessful; and that heteroplastic transplantations are always unsuccessful. Although the technical part of the problem of the transplantation of organs was completely solved long ago, this operation cannot yet be applied to human surgery. Homoplastic grafts alone would be of use; but before practicable, homoplastic transplantation must be rendered as safe as autoplastic transplantation.” During World War I, Carrel did pioneer work in the sterilization of septic wounds, primarily of the extremities. This experience led him to the conclusion that orthopedic surgery should be a separate specialty. He also believed that if transplantation of homologous tissues was to become a success, methods of long-term preservation of such tissues had to be refined.

Homologous vs Autogenous Fascial Grafts for Scleral Buckling-Reply

In Reply. —We thank Dr Davidorf for suggesting the use of homologous fascial grafts in patients with exposed buckles. We agree that this is a viable alternative to autogenous fascial grafts; however, it would still not be our first choice of material. Crawford,1who had much experience with both banked and autogenous fascia, preferred autogenous fascia because of the variability of the banked tissues in vivo. Banked fascia is also not always available in the community. It is also important to recognize that with even the remotest chance of acquiring viral conditions from homologous tissues, most patients would prefer autogenous grafts. The obtaining of autogenous fascial grafts is easy and quick and it has limited complications. We believe that the additional effort is well worthwhile.

Extrinsic Eyelid Ectropion

Extrinsic ectropion is caused by loss of skin around the orbital margins. Every patient with cicatricial ectropion should be assessed thoroughly to determine if the cause is intrinsic, extrinsic, or both. This assessment is extremely important when dealing with severe deformities after burns, cancer, or noma, for example. The assessment allows a proper planning of surgery. As a rule, the original size and location of the missing tissues should be recreated and the defect replaced by homologous tissues.

Effects of relaxation of mechanical tensions upon the early morphogenesis of Xenopus laevis embryos.

In Xenopus laevis embryos at the early gastrula stage, circumferential tensions of embryonic ectoderm were relaxed by making sagittal or transversal slits in the ventral parts of embryos and inserting into surgical cuts the sectors of homologous tissue from same-stage embryos. Changes in tensile patterns were controlled by measuring cell surface angles. Immediate decreases in surface cell wall tension as related to transversal wall tension were registered. Within minutes of the operation, the lobopodial activity of the inner ectodermal surface increased. The subsequent gastrulation movements were disturbed, germ layers partially mixed and archenteron reduced. The areas of extensive cell columnarization in the ectoderm of operated embryos were less regularly arranged and were extended much more ventrally than in intact embryos. Ventro-dorsal migration and latero-medial intercalation of mesodermal cells also were suppressed. As the operated embryos developed, we observed increases in the total amount of neural tissue, associated sometimes with duplication and even triplication of neural tubes, duplication of otic vesicles, partial fusion of axial rudiments, suppression of mesodermal segmentation and branching or bending of notochord. In the gravest cases the antero-posterior embryo polarity was disturbed. In some cases we observed the formation of axial rudiments in ventral implants. The role of tensions in determining the patterns of morphogenetic cell movements and in establishing the morphological order of normal development is discussed.

Induction of multifocal pancreatic cancer after inoculation of hamster pancreatic cancer cell line (PC-1) into a defined area of homologous pancreatic tissue

Inoculation of the pancreatic cancer cell line PC-1 into a defined area of the tail of the hamster pancreas led to development of multiple cancerous foci in the body of the pancreas along the main pancreatic duct. Each carcinoma showed identical histological characteristics and was completely separated from the others by regions of normal pancreatic tissue. This observation suggests spread of the cancer from the primary site in discontinuity through the ductal system of the pancreas.

Antisera to a Rabbit Urinary Tract Antigen also React with Human Bladder and Kidney Tissue

The mucin layer covering the bladder transitional cell mucosa appears to function as a primary defense mechanism against bacterial infection. We have previously prepared a glycoprotein fraction (GP1) from the urinary bladder mucosa of NZW rabbits and raised murine antisera against it. These antisera react with bladder, ureter and kidney tissue from rabbits, rats, guinea pigs, and hamsters. We now show that a similar substance occurs in human kidneys and bladder. In order to remove antibodies reactive with the Tamm-Horsfall protein (THP), the antisera were initially absorbed with an immunoadsorbent composed of purified human THP covalently bound to Sepharose CL-4B gel. Using an enzyme linked immunosorbent assay (ELISA) it could be shown that the absorbed antisera did not react with THP but retained a high titer in binding to GP1. Immunohistochemical procedures involving avidin-biotin-immunoperoxidase staining demonstrated that the absorbed anti-GP1 reacted well with six human urinary bladder biopsy specimens and two kidney autopsy specimens while normal murine sera showed little or no binding. Although this reactivity was not as strong as that found with homologous tissue (rabbit) these studies suggest that GP1, an antigen common to several animal species, is also related to a human urinary tract component. (J. Urol., 143: 414–417, 1990)

The fate of intravenously injected tissue ferritin in pregnant guinea-pigs.

The organ distribution of intravenously injected hepatic ferritin either labelled with 59Fe or with 59Fe and 125I, was studied in pregnant guinea-pigs. At 5 h 71.2% of injected 59Fe was present in the placenta and fetus. Transfer of 59Fe to the fetus was slow, with 11.2% present at 5 h and 38.6% at 21 h. Analysis of a placental cellular lysate for 59Fe and 125I revealed that the injected iron was present as intact ferritin at 2 h but by 21 h the ferritin had been catabolized, the 125I excreted and the 59Fe incorporated into endogenous ferritin. Most of the fetal 59Fe counts were detected in the liver, with 35.3% of the transferred 59Fe in ferritin, 30.4% in haemoglobin and 10.6% in a low molecular weight pool. The uptake of labelled ferritin by the placenta was inhibited by a 300-fold molar excess of unlabelled ferritin but not by albumin, asialofetuin or by the injection of carbon particles. A nonsignificant reduction in uptake was noted after injection of mannosylated bovine serum albumin. The mannosidase inhibitor swainsonine had no effect. Iron transfer to the fetus was not affected by various microtubular inhibitors. Presaturation of endogenous transferrin with oral carbonyl iron prevented iron release from the feto-placental unit back into the maternal circulation. In consequence, marrow 59Fe uptake by the maternal marrow was reduced. The ferrous chelator 2,2'-bipyridine significantly reduced 59Fe transfer to the fetus and this occurred irrespective of whether the chelator was given prior to or after 59Fe ferritin administration. The ferric chelator desferrioxamine had no such effect. Electron microscopy of placental tissues revealed endocytosis of ferritin molecules. These results indicate that the guinea-pig placenta takes up homologous tissue ferritin and transfers the iron slowly to the fetus after reductive mobilization. The process is compatible with a receptor-mediated pathway.

A critique of posterior lumbar interbody fusion: 12 years' experience with 250 patients

A comprehensive long-term follow-up analysis of the clinical and radiographic results of posterior lumbar interbody fusion for lumbar disk disease is presented. This 12-year experience with 250 patients is compared with a previous critique of our surgical management of lumbar disk disease by laminotomy and diskectomy alone. The clinical results and complication rates are comparable. However, posterior lumbar interbody fusion significantly reduces the rate of recurrent problems requiring subsequent surgery. Careful technique and judgment are mandatory for success with posterior lumbar interbody fusion. Homologous tissue bank bone grafts were found to be as successful as autogenous bone. Posterior lumbar interbody fusion represents an improvement in the surgical management of lumbar disk disease.

A Physiological Comparison of Bivalve Mollusc Cerebro-visceral Connectives With and Without Neurohemoglobin. I. Ultrastructural and Electrophysiological Characteristics.

The presence of hemoglobin in tissues of a small number of species is puzzling when homologous tissues of closely related species do not possess hemoglobin. Several species of bivalve molluscs possess nervous systems with nerve hemoglobin (neurohemoglobin). These systems were compared to nervous systems from other bivalve molluscs without neurohemoglobin to determine ultrastructural and electrophysiological characteristics under normoxic conditions in an attempt to locate any differences between these two types of nervous systems. Cerebro-visceral connectives from the bivalves Tellina alternata and Spisula solidissima with neurohemoglobin and Tagelus plebeius and Geukensia demissa without neurohemoglobin possess a perineural sheath, a subjacent peripheral layer of glial cells, and glial cell processes that enwrap bundles of 0.2-0.4 µm diameter axons. Neurohemoglobin-containing cerebro-visceral connectives have smaller axon bundles and more dense perineural sheaths than those without neurohemoglobin. These features may be important in oxygen delivery from the neurohemoglobin to the axons. Action potential traces, conduction velocities, refractory periods, strength-duration relationships, and temperature responses of all four connectives are typical of nerves possessing very small axons. There are no obvious electrophysiological differences between cerebro-visceral connectives with and without neurohemoglobin.

Transplantation of the fetal occipital cortex to the third ventricle of SCN-lesioned rats induces a diurnal rhythm in drinking behavior

Fetal hypothalamic transplants which include the suprachiasmatic nuclei (SCN), were shown previously to be capable of restoring circadian rhythmicity as manifested by both diurnal and free-running rhythms in drinking behavior in rats rendered arrhythmic by SCN lesions. The question arises as to whether the transplant must be homologous tissue or whether any other fetal brain tissue can produce similar effects. In this study rats with a lesion of the SCN and with clear loss of drinking rhythms received grafts of fetal occipital cortex placed into the third ventricle. Following the graft, animals were placed in LD conditions for 8 weeks and then in DD for another 8 weeks. The results indicate that the cortical graft induced recovery of a drinking rhythm under LD lighting conditions but that under DD the rhythm was lost again. These results suggest that non-hypothalamic tissue can mediate recovery of a diurnal rhythm but that hypothalamic tissue including the SCN is required to restore circadian function with maintenance of free-running rhythms.

Blood flow through cerebral collateral vessels one month after middle cerebral artery occlusion.

Acute occlusion of a middle cerebral artery (MCA) reduces cerebral blood flow in normotensive Wistar-Kyoto rats (WKY) and in stroke-prone spontaneously hypertensive rats (SHRSP). The goal of this study was to determine whether MCA occlusion produces a sustained reduction in cerebral blood flow or whether collateral vessels restore blood flow to normal levels. We measured blood flow through cerebral collateral vessels to the territory of the occluded MCA and to homologous tissue of the other hemisphere in WKY 1 month after occlusion of the MCA. Cerebral blood flow, measured with microspheres, was restored to normal levels under control conditions in the territory of the occluded MCA. During vasodilatation produced by seizures, blood flow and vascular conductance were increased to similar levels in tissue distal to the site of MCA occlusion and in the homologous tissue of the other hemisphere. MCA occlusion did not produce infarction in any of the WKY. In contrast, 1 month after MCA occlusion in SHRSP, a large atrophic infarct was invariably present in the territory of the occluded MCA. The number of collateral vessels to the territory of the MCA do not differ in SHRSP and WKY. Internal diameter and orientation of the anastomotic vessels differ in SHRSP and WKY. We conclude that, after 1 month of MCA occlusion, changes in the collateral vessels supplying the territory of the occluded MCA in WKY were sufficient to restore blood flow to normal under control conditions and to virtually normal levels during vasodilatation.(ABSTRACT TRUNCATED AT 250 WORDS)

In vitro studies on steroid metabolism by gonadal tissues from ambisexual teleosts : II. Conversion of [ 14C]androstenedione by the heterologous gonadal tissues of the protandric sea bream Pagellus acarne (Risso)

The heterologous gonadal tissues of the protandric sea bream Pagellus acarne were incubated with [ 14C]androstenedione in vitro. The tissues were taken from two males, an inverting specimen, and a female in early April. Although the testicular tissue regresses in the inverting fish the rate of 11β-hydroxylation in the male part of the gonad is at least as high as in the homologous portion of the “pure” male. No difference was found in the enzymatic pattern between the ovarian part of the inverting animal and that of the female. There is, however, a striking distinction in the metabolic activities of the pooled ovarian parts from two males and the homologous tissues from the inverting and female animals. They concern mainly the activities of 11β-hydroxylase and 17β-HSD. Moreover, ring A-reduction and the ratio of 5α 5β -reduced metabolites differ considerably from the corresponding gonadal tissues taken from the inverting and the female specimen. The possible physiological meaning of these findings remains to be elucidated.

Tissue distribution and characterization of LDH isozymes in two fishes of the order cypriniformes

Electrophoretic analysis of the lactate dehydrogenase isozyme patterns of several tissues ofHeteropneustes fossilis andClarias batrachus indicated that in addition to the LDH A and B genes found in these species the liver tissue ofClarias batrachus also possesses a liver specific LDHC. gene. The relative mobilities of the LDH-B4 and-A4 isozymes inHeteropneustes fossilis andClarias batrachus, are reversed. Further there are significant quantitative differences in the amounts of specific isozymes in homologous tissues of these two species and also in different tissues of a single species as documented in densitomeric tracings. The subunit composition of the LDH isozymes were confirmed by immunological procedures.