DigitalUM :: Browsing by Subject "Stereology"

Browsing by Subject "Stereology"

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Open Access
An ultrastructural stereologic study of aldosterone secreting adrenal adenomas and of adjacent zona glomerulosa
(Murcia : F. Hernández, 1988) Belloni, A. S.; Mantero, Franco; Rocco, Stefano; Gottardo, Giuseppe; Mazzocchi, G.; Nussdorfer, G.G.
The ultrastructure of four aldosterone secretine adenomas and of the adiacent zona glomerzosa has been described by "the use of stereological techniques. Adenomatous cells (about 2800 pm' in volume) invariably displayed a striking abundance of lipid droplets. which occupied about 30% of the cytoplasm. Mitochondria prevalently contained tubulo-lamellar or lamellar cristae, hut some cells exhibited organelles with vesicular cristae. Smooth endoplasmic reticulurn (SER) was not very abundant. Small lipofuscin-pigment granules were frequently seen and in a few cells they were exceedingly numerous. Zona glomerulosa cells were smaller (about 950 pm3 in \~olume) and possessed mitochondria with typical tubulo-lamellar cristae, a plentiful SER and few lipid droplets. They showed the ultrastructural features of elements actively engaged in steroid synthesis. The possible origin of aldosteronoma cells from the zona glomerulosa is discussed.
Open Access
Anencephalic fetuses can be an10 alternative for kidney transplantation, a stereological and histological investigation
(Murcia : F. Hernández, 2010) Kalaycıoğlu, Ahmet; Karaca, Mehmet; Can, Ismail; Keleş, Osman Nuri; Üçüncü, Yilmaz; Gündoğdu, Cemal; Uyanık, Abdullah; Ünal, Bünyami
In the study, stereological, histological, and anatomical techniques were used to investigate structural and morphometrical features of anencephalic and normal fetal kidneys. Twenty human fetal kidneys (5 male and 5 female anencephalic fetuses, and 5 male and 5 female normal fetuses) at gestational ages 30 to 35 weeks were examined. Our study used two basic research methods. One was conventional anatomical measurement at the macroscopic level, such as volume, length, weight, etc. The other consisted of conventional and modern microscopic techniques. The microscopic techniques were based on two research methods: histopathological examination at light microscopic level and stereological estimations, including mean kidney volumes, obtained by the Cavalieri method, and the total number and mean height of the glomeruli via the physical dissector method. There was no statistical difference between the two groups in terms of width, height, weight, and fluid replacement volumes. Microscopic quantitative assessment found no statistical differences either, in terms of the kidney volumes and the number and height of the glomeruli. Our findings suggest that kidneys from anencephalic infants may be a suitable alternative for renal transplantation
Open Access
Automated systematic random sampling and Cavalieri stereology of histologic sections demonstrating acute tubular necrosis after cardiac arrest and cardiopulmonary resuscitation in the mouse
(Universidad de Murcia. Departamento de Biología Celular e Histología, 2018) Wakasaki, Rumie; Eiwaz, Mahaba; McClellan, Nicholas; Matsushita, Katsuyuki; Kirsti Golgotiu, Kirsti Golgotiu; Hutchens, Michael P.
Open Access
Compensatory adrenal growth in aldosterone-treated male and female hamsters
(Murcia : F. Hernández, 1989) Kasprzak, A.; Malendowicz, L.K.
The aim of the study was to investigate the compensatory adrenal growth in aldosterone-treated male and female hamsters. Hemiadrenalectomised and sham-operated animals were treated for 5 days with a daily d-aldosterone dose of 25 pglanimal. In both male and female aldosterone-treated hamsters monoadrenalectomy did not change the relative adrenal weight if compared with sham-operated groups. The fasciculata zonae of monoadrenalectomised aldosterone- treated males was larger and contained more parenchyma1 cells than in appropriate control group. There was no difference in the volume of adrenocortical zones, average cell volume and in cell number between sham-operated and unilaterally adrenalectomised females. In vitro 3H-thymidine incorporation per adrenal was markedly higher in monoadrenalectomised than in sham-operated aldosterone-treated males while the opposite was true for female hamsters. Thus, the action of aldosterone on CAG in the hamster seems to depend on sex, with no effect in males and inhibitory action in females.
Open Access
Counting particles in tissue sections: Choices of methods and importance of calibration to minimize biases
(Murcia : F. Hernández, 2002) von Bartheld, C.S.
Investigators must choose between counting methods to quantify microscopic particles in tissues. The c o nventional profile-based ("model-based" or "2D-") counting methods have been criticized for their potential biases due to assumptions about shapes, sizes, and orientation of particles when converting profile counts into cell numbers. New stereological methods ("designbased" or "3D-") methods such as the optical disector or p hysical disector were initially introduced as being inherently unbiased. Recent calibration analyses and comparisons of results from different investigators have r evealed the potential for significant biases in the most efficient and most frequently used design-based method, the optical disector. This rev i ew aims to objective l y assess the strengths and limitations of current profi l e - and disector-based cell counting methods by examination of studies in which these methods have been calibrated against the "gold-standard", counts obtained by 3-dimensional reconstruction of serial sections. Advantages and disadvantages of each counting method and the associated embedding and sectioning techniques are compared and frequent mistakes and pitfalls of each technique are discussed. The importance of a calibration step for each technique is emphasized, and a protocol is provided for a quick and simple calibration by a "sampling" 3-D reconstruction of limited serial sections. Trends in the usage of counting methods are analyzed in four major journals. It is hoped that this r ev i ew will be helpful, for both inv e s t i gators and manuscript rev i ewers, in clarifying some of the contentious issues in the choice and implementation of appropriate methods for particle counting in tissue sections.
Embargo
DNA-Ploidy, morphometric-stereological and P-Glycoprotein study of superficial bladder carcinomas
(S. Karger AG, 1992) Sánchez Fernández de Sevilla, M. C.; Gil Salom, M.; Pérez Bacete, M.; Morell Cuadreny, L.; Martínez Díaz, F.; Iborra Juan, I.; Fenollosa Entrena, B.; Llombart Bosch, A.; Oftalmología, Optometría, Otorrinolaringología y Anatomía Patológica
We carried out a DNA-ploidy, morphometri􀀜stereolcgic and P-glycoprotein study on 40 newly diagnosed superficial bladder cancer patients (G l-G2), correlating the results with histological grade and clinical outcome. Variations in the number of patients who present recurrences, progression or remain tumor-free during the whole follow-up period (at least 5 years) were not significant when related to nuclear size, proliferative diploid index, presl!nce of aneuploidy and expression of P-glycoprotein. lt is striking how the majority of disease-free subjects showed a proliferative diploid index higher than 10%. Moreoyer .. 3 of them presented a11 aneuploid cell population. In our study, only histological grade showed a significant discriminatory level in terms of progression versus no progression in patients with superficial bladder cancer.
Open Access
Evaluation of volume-weighted mean nuclear volume in endometrial lesions
(Murcia : F. Hernández, 1993) Artacho-Perula, E.; Roldan-Villalobos, R.
The individual nuclear size was studied in three groups of endometrial samples (simple hyperplasia -SH-, atypical hyperplasia -AH-, and well-differentiated adenocarcinoma -WDA-). The application of recent semiquantitative systems in combination with stereological methods permits a simple, quick and unbiased estimation of the volume-weighted mean nuclear volume V,(nucl). We have found an increase in the V,(nucl) from SH to AH to WDA. There are significant differences between the mean of the three groups (pc0.01). The variance associated with estimates of V,(nucl) is mainly provided by differences among lesions; i.e. patients. This capacity for discriminating may be associated with gland and lumen endometrial quantification to improve the correct diagnosis of endometrial samples.
Open Access
Glomerular profile numerical density per area and mean glomerular volume in rats submitted to nitric oxide synthase blockade
(Murcia : F. Hernández, 2001) Pereira, L.M.M.; Mandarim-de-Lacerda, Carlos A.
Rats submitted to chronic inhibition of nitric oxide synthase (NOS) have developed systemic hypertension and consequent renal injury. The present study aims to determine glomerular quantitative changes due to NOS inhibition in rats. Adults and normotensive Wistar rats were separated into control and L-NAME groups (each group n=10). The animals received water and food ad libitum, while L-NAME rats received N ~ - Nitro-L-Arginine methyl Ester hydrochloride to inhibit NOS (50mg/kg/day) in drinking water during 40 days. After that period the rats were sacrificed, the kidneys were removed, measured, and prepared for histological and stereological analyses. The glomerular density per area [NA(giom)] and the mean glomerular volume [Y] were determined per animal in 15 random fields. In LNAME rat the blood pressure was 76% higher than the respective control group with the same age. Glomeruli had global or segmental glomerular sclerosis; some glomeruli only presented an atrophic structure. The renal volume was not different between control and L-NAME rats (p>0.05). However, L-NAME rats had the NA(giom) 33% smaller than the control rats (p=0.0001) and, concomitantly, L-NAME rats had the Y (glom) 33% higher than the control ones (p=0.004). These results demonstrate morphological renal alterations caused by NOS inhibition and hypertension.
Open Access
Histological and stereological insights into renal and adrenal changes in pregnant rats exposed to wood smoke-derived PM2.5
(Universidad de Murcia, Departamento de Biologia Celular e Histiologia, 2025) Salinas, P.; Villarroel, F.; González Torres, C.; Lazcano, T.; Silva, J.; Maulen, A.; Rojas, E.
Air pollution, particularly fine particulate matter (PM2.5), is a global health issue affecting millions. In southern Chile, firewood used for heating exacerbates pollution, especially in winter. This study examines the impact of wood smoke-derived PM2.5 on kidney and adrenal gland morphology in pregnant rats. It evaluates chronic PM2.5 exposure effects during pregestational and gestational periods in Sprague-Dawley rats. Pregnant rats were exposed to PM2.5 in Temuco, a city with high wood smoke pollution. Filtered and unfiltered air chambers simulated different exposure conditions. Histological and stereological analyses were conducted on rat kidneys and adrenal glands using systematic sampling and STEPanizer software. Findings showed significant changes in renal and adrenal morphology due to PM2.5 exposure. In the kidney, variations were observed in glomerular compaction, proximal convoluted tubules, and medullary rays. In the adrenal gland, the zona fasciculata showed decreased acidophilia and lipid content, reduced cytoplasmic homogeneity, and the appearance of empty spaces. These effects were more pronounced in rats exposed to unfiltered air during both pregestational and gestational periods. Wood smoke-derived PM2.5 exposure significantly impacts kidney and adrenal morphology in pregnant rats, emphasizing the need for strategies to reduce environmental pollutant exposure during critical developmental periods to protect maternal-fetal health.
Open Access
In search for a gold-standard procedure to count motor neurons in the spinal cord
(Universidad de Murcia. Departamento de Biología Celular e Histología, 2018) Ferrucci, Michela; Lazzeri, Gloria; Flaibani, Marina; Biagioni, Francesca; Cantini, Federica; Madonna, Michele; Bucci, Domenico; Limanaqi, Fiona; Soldani, Paola; Fornai, Francesco
Counting motor neurons within the spinal cord and brainstem represents a seminal step to comprehend the anatomy and physiology of the final common pathway sourcing from the CNS. Motor neuron loss allows to assess the severity of motor neuron disorders while providing a tool to assess disease modifying effects. Counting motor neurons at first implies gold standard identification methods. In fact, motor neurons may occur within mixed nuclei housing a considerable amount of neurons other than motor neurons. In the present review, we analyse various approaches to count motor neurons emphasizing both the benefits and bias of each protocol. A special emphasis is placed on discussing automated stereology. When automated stereology does not take into account sitespecificity and does not distinguish between heterogeneous neuronal populations, it may confound data making such a procedure a sort of “guide for the perplex”. Thus, if on the one hand automated stereology improves our ability to quantify neuronal populations, it may also hide false positives/negatives in neuronal counts. For instance, classic staining for antigens such as SMI-32, SMN and ChAT, which are routinely considered to be specific for motor neurons, may also occur in other neuronal types of the spinal cord. Even site specificity within Lamina IX may be misleading due to neuronal populations having a size and shape typical of motor neurons. This is the case of spinal border cells, which often surpass the border of Lamina VII and intermingle with motor neurons of Lamina IX. The present article discusses the need to join automated stereology with a dedicated knowledge of each specific neuroanatomical setting.
Open Access
Morphological changes induced by colchicine in the chick optic cup in early stages of development. A stereological study
(Murcia : F. Hernández, 1999) Abadía Molina, F.; Calvente, R.; Carmona Martos, R.; Luján, R.; Abadía Fenoll, F.
In this study chick embryo optic cups at HH stage 13 of development were analyzed under normal conditions and after inoculation with colchicine for 1, 2, 4, and 8 h. Several changes were seen after these periods of treatment: 1) modifications of the structure, with thicker regions in the cup and a general decrease in the total volume according to the duration of exposure to the drug (about 4 times less than normal, 5,035 x lo3 ym3 vs 1,334 x lo3 ym3 after 8 h of treatrnent); 2) enlargement of the ventricular cavity and its closure, due to failure of approximation of retina1 and pigmentary layers; 3) failure of lens development, with delay and impairment of pit formation and deformation of al1 structures; lens volume was less than normal (about 4 times less, 2,148 x 103 pm3 vs 658 x lo3 pm3. after 8 h of treatment); 4) a general segregation of the cells making up the structure, principally in the more active proliferating zones. The local alterations found are described
Open Access
Morphological differentiation of mitochondria in the early chick embryo: a stereological analysis
(Murcia : F. Hernández, 1986) Paz, P. de; Zapata, A.; Renau-Piqueras, J.; Miragal, F.
The morphological evolution of mitochondria in three cell types of chick embryo in neurulation was analyzed by stereological methods. Mitochondria, showing a random distribution, were characterized by moderate electron-dense matrices and normal cristae. The numerical density of mitochondria significantly increased in the neuroectoderm and epiblastic cells while their volume density remained unchanged. The mitochondria in mesoderm cells were ellipsoidal (axial ratio 2:l) at stages 5 and 8 although they underwent an elongation in neuroectoderm and epiblastic cells (axial ratio from 2: 1 to 1.6: 1). The individual size of "average mitochondria" in the mesoderm cells was smaller than in other cell types. The total V/S (volume/surface) ratio of mitochondria decreased during neurulation. These morphological changes have been discussed emphasizing the possible metabolical role of mitochondria during morphogenesis
Open Access
Soy isoflavone effects on the adrenal glands of orchidectomized adult male rats: a comprehensive histological and hormonal study
(Universidad de Murcia. Departamento de Biología Celular e Histología, 2018) Milošević, Verica Lj.; Severs, Walter B.; Ristić, Nataša M.; Manojlović Stojanoski, Milica N.; Popovska Perčinić, Florina V.; Šošić Jurjević, Branka T.; Pendovski, Lazo B.; Trifunović, Svetlana L.; Miler, Marko Š.; Ajdžanović, Vladimir Z.
Genistein (G) and related soy phytoestrogens have been studied for potential usefulness in different chronic diseases, and may ameliorate signs of aging. They have a profound influence on the hypothalamopituitary-adrenal (HPA) axis. The present study utilized the rat model of mild andropause to thoroughly evaluate the effects of G and soy extract on the adrenal gland and related blood hormones. Adult male rats were orchidectomized (Orx) or sham operated (SO). Orx rats received daily subcutaneous injections for 3 weeks of solvent, or G (Orx+G, 30 mg/kg), or commercial soy extract (Orx+Soy, 30 mg/kg). Adrenal glands and blood were harvested at the end of the treatment for hormone analyses, histology and design-based stereology. Compared to SO rats Orx evoked significant (P<0.05) changes including: the replicating cell number in the 3 adrenocortical zones; vascularity and cortical volume and blood levels of adrenocorticotropic hormone (ACTH), aldosterone and dehydroepiandrosterone (DHEA). When comparing Orx vs. Orx+G groups the following significant (P<0.05) changes were observed: a further increase in number of replicating cells in zonas glomerulosa and reticularis, vasculature network presence, cortical and zona reticularis volumes, ACTH and corticosterone concentrations, and lower DHEA levels. Comparing Orx vs. Orx+Soy resulted in elevated (P<0.05) ACTH and corticosterone levels. Structural integrity of the adrenal gland was unchanged vs. SO rats. Overall, G and soy extract treatments resulted in proliferative activity and/or vasculature support in the adrenal cortex. The data and current literature support the impression of a beneficial effect of soy components on the homeostatic response to stress.
Open Access
Stereologic analysis of the in vivo alveolar type II cell response to isoproterenol or saline administration
(Murcia : F. Hernández, 1987) Smith, Dennis M.; Griffin, Lawrence S.
Previous studies have demonstrated enhanced secretion of pulmonary surfactant from type I1 alveolar epithelial cells following 8-adrenergic stimulation. The present study was undertaken in order to provide quantitative morphologic data supporting this effect in vivo. Adult male Sprague-Dawley rats were injected subcutaneously with 150 mg/kg L-isoproterenol, a widerange 8-adrenergic agonist, and killed at times 0.25 - 12 hours post-injection. Other rats were similarly injected with saline, and killed at times 0.25 - 6 hours post-injection. A third group of animals was not injected, nor handled, prior to the time of death, and served as baseline controls. Stereologic analysis of the intracellular organelles of the type I1 celss in the animals treated with L-isoproterenol revealed a significant decrease in lamellar body volume density, indicating increased secretion of surfactant, at 0.5 - 4 hours. The rough endoplasmic reticulum volume density increased significantly at 2 - 6 hours, indicating increased synthetic activity. In contrast, the type I1 cells of salineinjected animals showed no significant evidence of increased secretion, but did demonstrate a large increase in synthetic activity, resulting in many large lamellar bodies at 2 and 4 hours post-injection. The results of this study provide quantitative morphological evidence of 8-adrenergic stimulation of the secretion and synthesis of pulmonary surfactant secretion by type I1 cells of the adult rat lung in vivo. In addition, they suggest an enhancement of surfactant synthesis following saline injection, which is perhaps based on endogenous catecholamine release.
Open Access
Stereological study of the synaptic profiles belonging to interneurons in the dorsal lateral geniculate nucleus of the rabbit
(Murcia : F. Hernández, 1992) Carmona Martos, R.; Abadía Molina, F.; Luján Miras, R.; Calvente Iglesias, R.; Abadía Fenoll, F.
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Open Access
Stereological study of tissue compartments of the human spleen
(Murcia : F. Hernández, 1996) Milicevic, Z.; Cuschieri, A.; Xuereb, A.; Milicevic, N.M.
Morphometric reports on animal and human spleen are very few and no studies have been carried out using stereological methods to investigate all of the tissue compartments of the human spleen. Eighteen samples of spleens, which were either surgically removed after traumatic injury or during treatment for early stage carcinoma or gastric ulcer, were investigated. The point-counting method was used to study the volume densities of the following tissue compartments: red pulp, perifollicular zone, white pulp (this tissue compartment was divided in two subcompartments: follicles and periarteriolar lymphatic sheath), marginal zone and connective tissue of trabeculas. The following stereological parameters of the follicles were investigated: the number of follicles per mm2 of spleen section, numerical density, volume density, and the mean follicular diameter. The identity of spleen tissue compartments was verified using immunohistochemical staining for B- and T-lymphocytes. The volume densities of tissue compartments, as well as stereological parameters of lymphoid follicles, were similar in both groups of splenic samples, except for the volume densities of perifollicular zone and periarteriolar lymphatic sheath, where a statistically significant difference was registered.
Open Access
Structure and hormonal output of the adrenal gland after experimental estrogenization of male rats
(Universidad de Murcia, Departamento Histología e Histopatología, 2025) Pavle Ćosić; Svetlana Trifunović; Branka Šošić-Jurjević; Marko Miler; Branko Filipović; Milica Manojlović-Stojanoski; Vladimir Ajdžanović; Histología e Histopatología
Orchidectomy and estrogenization of the male represent a procedure that is applicable in sex reassignment or in prostate cancer therapy. This approach has an influence on the hypothalamic-pituitaryadrenal axis and thus affects cardiovascular function and metabolism. We utilized orchidectomized rats to evaluate the effects of estradiol on the structure and hormonal output of the adrenal gland. Adult Wistar rats were divided into sham-operated (SO; n=7), orchidectomized (Orx; n=7), and estradiol-treated orchidectomized (Orx+E; n=7) groups. Estradiol-dipropionate (0.625 mg/kg b.m.) was administered subcutaneously for three weeks, while the SO and Orx groups received vehicle alone. Set objectives were achieved using histochemistry/immunohistochemistry, stereology, and immunoassays. In Orx+E rats, the hormonal milieu was characterized by decreased testosterone and increased ACTH, compared with the Orx group. Also, orchidectomy and estradiol treatment provoked a significant increase in adrenal cortex volume and volume of ZF per se, with increased cell and nuclei volumes in all three adrenocortical zones (ZG, ZF, and ZR), in comparison with Orx rats. Concentrations of aldosterone in blood, as well as corticosterone in blood and adrenal tissue were increased, while circulating DHEA was decreased (with increased immuno-expression of adrenocortical CYP 17 enzyme), all in Orx+E compared with Orx animals. The wide zonal distribution of VEGF and the pronounced blood supply within the ZF of Orx+E animals acted to support the synthesis and secretion of corticosteroids. These results seem cautionary in the context of young male estrogenization, given the negative impact of high mineralocorticoids and glucocorticoids on cardiovascular function and metabolism.
Open Access
The hepatocytes of the brown trout (Salmo trutta f. fario):A quantitative study using design-based stereology
(Murcia : F. Hernández, 2001) Rocha, E.; Monteiro, R.A.F.; Oliveira, M.H.; Silva, M.W.
A stereological study was performed on brown trout hepatocytes aiming to disclose whether there are basic gender differences when minimal levels of sex hormones exist, and also to establish a platform for both interspecific comparisons and physiological correlations. We used the so-called "design-based stereology" (with no shape, size or orientation assumptions) and also some new related statistics. Twoyear- old brown trout were collected in April, and the livers were fixed by perfusion. From liver slicing to microscopical field selection, systematic sampling was used. Stereology was applied at light and electron microscopy. Target parameters were the relative and total hepatocyte number, the mean individual hepatocyte volume and surface, and also both relative and total volumes, and surfaces, either of organelles or of cell compartments. Observed variability was usually high, but the precision of estimates was proved to be globaily adequate facing the true biological variation amongst specimens. Females had more hepatocytes per liver ( 1 . 7 9 ~ 1 0v~s. 1 . 1 2~1 0~C) .o nsidering the individual hepatocytes, whereas no gender differences were detected in the cell volume, males had higher values of nuclear volume (199 vs. 151 pm3) and surface (170 vs. 131 pm2), endoplasmic reticulum volume I 1300 vs. 824 pm3), and microvilli volume (82 vs. 54 pm ) and surface (1445 vs. 975 pm2). However, when dealing with quantities per liver, gender differences were found only in the volumes of dense bodies (56 vs. 97 mm3) and of residual cytoplasm (169 vs. 341 mm3) - both volumes were higher in females. Functional implications of data are discussed, namely that females seem to have basic structural traits for coping with the later demands of breeding. Data also support that structural remodelling of hepatocytes occurs after breeding, urging to pursue seasonal studies (namely on lysosomes). We advanced the hypothesis that genders differ in microvilli surface just to maintain an optimal physiological surface-to-volume ratio. Interspecific similarities and differences were disclosed. For example, the number of hepatocytes/cm3 of parenchyma of brown trout was much lower than those reported in rainbow trout, but in both trouts femaies seem to have an higher cell number. In addition, when comparing the size of hepatocytes of brown trout with that from other fish and mammals it was suggested that major interspecific differences exist.

Browsing by Subject "Stereology"

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