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Morphometrical Analysis (morphometrical + analysis)
Selected AbstractsCharacteristics of Rabbit Transgenic Mammary Gland Expressing Recombinant Human Factor VIIIANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 1 2009P. Chrenek Summary The objective of this research was to compare (i) the content of milk protein and recombinant human factor VIII (rhFVIII) in the milk of transgenic and non-transgenic rabbit females at three lactations and (ii) histological structure, ultrastructural morphology and occurrence of apoptosis in rabbit transgenic and non-transgenic mammary gland during third lactation and involution. Significant differences (t0.05) in milk protein content were found between transgenic and non-transgenic at all three lactations. The percentage of apoptotic cells was significantly higher (t0.01) in non-transgenic ones compared with transgenic mammary gland tissues (6.5% versus 2.4%) taken at the involution stage. Morphometrical analysis of histological preparations at the involution stage detected a significantly higher (t0.05) relative volume of lumen in transgenic animals compared with non-transgenic ones (60.00 versus 46.51%). Ultrastructural morphology of the transgenic mammary gland epithelium at the involution stage revealed an increased relative volume of protein globules (t0.05); at the lactation stage, a significantly higher volume of mitochondria (13.8%) compared with the non-transgenic (9.8%) ones was observed. These results, although revealing differences in some parameters of ultrastructure and histology, indicate no harmful effect of the mouse whey acid protein-hFVIII transgene expression on the state of mammary gland of transgenic rabbit females. [source] Disturbed morphogenesis of cardiac outflow tract and increased rate of aortic arch anomalies in the offspring of diabetic ratsBIRTH DEFECTS RESEARCH, Issue 12 2004Daniël G.M. Molin Abstract BACKGROUND Maternal diabetes (MD) is a risk factor for offspring to develop cardiovascular anomalies; this is of growing clinical concern since the number of women in childbearing age with compromised glucose homeostasis is increasing. Hyperglycemia abrogates cardiovascular development in vitro; however, a link to cardiovascular defects in diabetic offspring remains to be investigated. METHODS We have studied cardiovascular development in offspring of MD rats by examining serial histological sections of GD 12.0,18.0 offspring. Development of pharyngeal arch artery malformations was analyzed and related to intracardiac anomalies. RESULTS Pharyngeal arch artery and intracardiac defects were present in 27 of 37 MD GD 13.0,18.0 offspring. Early sixth arch arteries showed abrogated arteriogenesis, whereas fourth arch artery defects developed as a result of abnormal remodeling. Morphometrical analysis showed increased apoptosis in regressing artery segments and reduced apoptosis in persisting artery segments. Double outlet right ventricle with infundibular stenosis (tetralogy of Fallot) was predominantly found in combination with sixth artery defects and pulmonary atresia. As confirmed by morphometric analysis and three-dimensional (3D)-reconstructions, outflow tract defects coincided with endocardial cushion hypoplasia. Cases with teratology of Fallot additionally showed a shorter outflow tract. No relation with apoptosis or disturbed neural crest cell migration was found. CONCLUSIONS Our data uniquely demonstrate mechanistic differences involved in the development of sixth and fourth artery anomalies. Whereas increased apoptosis induces fourth artery anomalies, pulmonary outflow obstruction abrogates sixth artery differentiation independent of apoptosis. The model presented allows analysis of diabetic conditions on cardiovascular development in vivo, essential for elucidating this teratology. Birth Defects Research (Part A), 2004. © 2004 Wiley-Liss, Inc. [source] Enhanced rat sciatic nerve regeneration through silicon tubes filled with pyrroloquinoline quinoneMICROSURGERY, Issue 4 2005Shiqing Liu M.D. Pyrroloquinoline quinone (PQQ) is an antioxidant that also stimulates nerve growth factor (NGF) synthesis and secretion. In an earlier pilot study in our laboratory, Schwann cell growth was accelerated, and NGF mRNA expression and NGF secretion were promoted. The present study was designed to explore the possible nerve-inducing effect of PQQ on a nerve tube model over a 1-cm segmental deficit. An 8-mm sciatic nerve deficit was created in a rat model and bridged by a 1-cm silicone tube. Then,10 ,l of 0.03 mmol/l PQQ were perfused into the silicone chamber in the PQQ group. The same volume of normal saline was delivered in the control group. Each animal underwent functional observation (SFI) at 2-week intervals and electrophysiological studies at 4-week intervals for 12 weeks. Histological and morphometrical analyses were performed at the end of the experiment, 12 weeks after tube implantation. Using a digital image-analysis system, thickness of the myelin sheath was measured, and total numbers of regenerated axons were counted. There was a significant difference in SFI, electrophysiological index (motor-nerve conduct velocity and amplitude of activity potential), and morphometrical results (regenerated axon number and thickness of myelin sheath) in nerve regeneration between the PQQ group and controls (P < 0.05). More mature, high-density, newly regenerated nerve was observed in the PQQ group. We conclude that PQQ is a potent enhancer for the regeneration of peripheral nerves. © 2005 Wiley-Liss, Inc. Microsurgery 25:329,337, 2005. [source] Evaluation of blood vessel ingrowth in fibrin gel subject to type and concentration of growth factorsJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 9a 2009A. Arkudas Abstract Our aim was to quantitatively assess the angiogenetic effects of VEGF and bFGF immobilized in a fibrin-based drug delivery system in a suitable subcutaneous rat model. After evaluation of a suitable implantation technique (6 rats), four teflon isolation chambers containing fibrin gel matrices were implanted subcutaneously in an upside-down fashion on the back of 30 Lewis rats. The matrices consisted of 500 ,l fibrin gel with two different fibrinogen concentrations (10 mg/ml or 40 mg/ml fibrinogen) and 2 I.U./ml thrombin and contained VEGF and bFGF in five different concentrations (0 to 250 ng/ml each). At 3, 7 and 14 days after implantation, matrices were explanted and subjected to histological and morphometrical analysis. At 1 week, the volume of the fibrin clots was significantly smaller in the 100 and 250 ng/ml VEGF and bFGF groups in comparison to lower concentrated growth factors. At 1 and 2 weeks, the use of growth factors in low concentrations (25 ng/ml VEGF and bFGF) significantly increased the amount of fibrovascular tissue, average fraction of blood vessels and number of blood vessels at the matrix,host interface in comparison to growth factor-free controls. Higher concentrations were neither associated with further increase of tissue formation nor with increased sprouting of blood vessels in this model. This study demonstrates that fibrin gel-immobilized angioinductive growth factors efficiently stimulate generation of fibrovascular tissue and sprouting of blood vessels in a newly developed subcutaneous upside-down isolation chamber model with an optimum between 25 and 100 ng/ml. [source] Parotid sialosis: morphometrical analysis of the glandular parenchyme and stroma among diabetic and alcoholic patientsJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 1 2010Carolina Merlo J Oral Pathol Med (2010) 39: 10,15 Background:, Among the agents that cause parotid sialosis, diabetes mellitus type 2 and chronic alcoholism are included. In this study, the morphometrical modifications in the diabetic parotid sialosis were determined to compare them with the histopathological characteristics of alcoholic parotid sialosis. Methods:, Five parotid biopsy samples obtained from patients with diabetic sialosis, 12 samples from patients with alcoholic sialosis and seven from individuals without these pathologies (control group) were analyzed. A morphometrical study of parotid parenchyme and stroma, using a digital image analyzer attached to an optical microscope, was carried out. Dimensions of serous acini and striated ducts, the area occupied by the fatty tissue, and the number of ducts were recorded. Mean values were compared using the Mann,Whitney U -test (P , 0.05). Results:, The variables analyzed in diabetic patients did not show significant differences with respect to the control group. However, when diabetics were compared with alcoholics, the alcoholics exhibited a noticeable reduction in the proportion of fatty tissue of stroma and a significant development of ductal epithelium that contributed to increase the caliber of the striated ducts. Conclusions:, These results indicate that the glandular hypertrophy in the diabetic parotid sialosis is not directly associated with the ductal and acinar size, amount of fatty tissue and ductal hyperplasy. Nevertheless, these findings show that the ductal dimensions and the proportion of adipose tissue are variables that allow us to establish histopathological differences between diabetic and alcoholic sialosis. [source] Tissue engineering of peripheral nerves: Epineurial grafts with application of cultured Schwann cellsMICROSURGERY, Issue 1 2003H. Fansa M.D., Ph.D. After a simple nerve lesion, primary microsurgical suture is the treatment of choice. A nerve gap has to be bridged, with a nerve graft sacrificing a functioning nerve. Alternatively, tissue engineering of nerve grafts has become a subject of experimental research. It is evident that nerve regeneration requires not only an autologous, allogenous, or biodegradable scaffold, but additional interactions with regeneration-promoting Schwann cells. In this study, we compared epineurial and acellularized epineurial tubes with and without application of cultured Schwann cells as alternative grafts in a rat sciatic nerve model. Autologous nerve grafts served as controls. Evaluation was performed after 6 weeks; afterwards, sections of the graft and distal nerve were harvested for histological and morphometrical analysis. Compared to controls, all groups showed a significantly lower number of axons, less well-shaped remyelinizated axons, and a delay in clinical recovery (e.g., toe spread). The presented technique with application of Schwann cells into epineurial tubes did not offer any major advantages for nerve regeneration. Thus, in this applied model, neither the implantation of untreated nor the implantation of acellularized epineurial tubes with cultured Schwann cells to bridge nerve defects was capable of presenting a serious alternative to the present gold standard of conventional nerve grafts for bridging nerve defects in this model. © 2003 Wiley-Liss, Inc. MICROSURGERY 23:72,77 2003 [source] Low grade diffuse gliomas: Shared cellular composition and morphometric differencesNEUROPATHOLOGY, Issue 5 2008Sawako Kinjo Low grade diffuse gliomas arising in the brain are challenging to treat because of their ability to infiltrate adjacent tissue. We attempted to clarify the cellular composition and histopathological features of low grade gliomas by utilizing morphometric and immunohistochemical analyses. Seventy-eight cases of low grade gliomas were examined including 21 diffuse astrocytomas (DA), 36 oligodendrogliomas (OL), and 21 oligoastrocytomas (OA), based on the WHO classification system. Moreover, OL were subdivided into three types based on the morphological characteristics advocated by Daumas-Duport et al.: OL type I, OL type II, and OL type III. The cellularity, nuclear form factor, and conditional entropy corresponding to the nuclear pleomorphism were measured in each sample by the image analysis software "Gunmetry." Twenty-two cases were immunohistochemically analyzed for the expression of several antigens. Morphometric data indicated that the cellularity of OL type II was significantly higher than that of DA, and that the conditional entropy of OL type III was significantly lower than that of DA. Although the results of the immunohistochemical studies were almost consistent with previous reports, there were significant differences in the expression of GFAP, nestin and p53 between DA and OL. Double immunostaining revealed that expression of Olig2 and GFAP, and Olig2 and nestin was mutually exclusive in most glioma cells. Moreover, the coexpression of nestin and GFAP occurred in DA and OA, but not in OL. We conclude that each glioma include cells expressing GFAP, cells expressing nestin, and cells expressing Olig2 in a characteristic proportion for each tumor type. We suggest that diffuse gliomas share cellular compositions in different ratios and that they can be distinguished by morphometrical analysis. [source] Hypoplasia of the arcuate nucleus and maternal smoking during pregnancy in sudden unexplained perinatal and infant deathNEUROPATHOLOGY, Issue 4 2004Anna Maria Lavezzi Maternal smoking during pregnancy is the most important risk factor for sudden perinatal and infant death in more industrialized countries. The frequent observation of hypoplasia of the arcuate nucleus in the brainstem of these victims prompted the verification of whether maternal cigarette smoking could be related to defective development of this nucleus during intrauterine life, by affecting the expression of specific genes involved in its developmental process. In serial sections of the brainstem of 54 cases of sudden and unexplained fetal and infant deaths (13 stillbirths, 7 neonatal deaths and 34 sudden infant death syndrome (SIDS) victims), morphological and morphometrical analysis was used to observe the different structural alterations of the arcuate nucleus (bilateral hypoplasia, monolateral hypoplasia, partial hypoplasia, delayed neuronal maturation and decreased neuronal density) detected in 24 cases (44%). Correlating this finding with smoking in pregnancy, a significantly increased incidence of cytoarchitectural alterations of the arcuate nucleus was found in stillborns and SIDS victims with smoker mothers compared to victims with non-smoker mothers. Moreover, the observation of a wide range of developing morphological defects of the arcuate nucleus related to maternal smoking led to the hypothesis that the constituents of the gas phase in cigarette smoke could directly affect the expression of genes involved in the development of this nucleus, such as the homeobox En-2 gene. [source] Speciation on the Azores islands: congruent patterns in shell morphology, genital anatomy, and molecular markers in endemic land snails (Gastropoda, Leptaxinae)BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2009KURT JORDAENS Morphological data, in combination with molecular data, may provide invaluable insights into speciation processes on archipelagos. Land snails offer ample opportunities to evalutate adaptive and non-adaptive speciation scenarios. However, studies investigating processes of differentiation and speciation on the Azores are scarce. The present study comprises a morphometrical analysis of shell and genital characters in a group of Azorean land snails (Pulmonata, Leptaxinae). Geographical isolation appears to be an important mechanism underlying morphological and molecular differentiation in the Azorean Leptaxini, instead of adaptive radiation through ecological differentiation. Nevertheless, we could not exclude the occurrence of ecological speciation on the oldest island (Santa Maria) where two species that markedly differ in shell-shape co-occur. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 97, 166,176. [source] | |||||||||||||