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PubMedDate not supplied

Effect of hydrostatic pressure on morphological and ultrastructural aspects of normal and osteoarthritic human articular chondrocytes.

In this work we studied the morphological and ultrastructural aspects of normal and osteoarthritic (OA) human articular chondrocytes cultivated in alginate gel for 48 hours. After this period the chondrocytes in Petri dishes were exposed to cyclic pressurization (minimum pressure 1 MPa and maximum pressure 5 MPa) at 0.25 Hz frequency for three hours. In other loading procedures the cells were exposed to continuous pressure (24 MPa) for three hours. Some dishes were not pressurised and these served as controls. The cells were then fixed for transmission electron microscopy (T.E.M.) and for scanning electron microscopy (S.E.M.). No ultrastructural changes were observed in normal chondrocytes exposed at physiological pressure. OA cells placed under physiological pressure showed a partial recovery on morphological and ultrastructural aspects. Normal and OA samples exposed to continuous pressure (24 MPa) showed a morphological worsening in both T.E.M. and S.E.M. studies.

Adult↗

PubMed1999

The age-related quantitative ultrastructural changes in pinealocytes of gerbils.

OBJECTIVES. Relatively few ultrastructural studies of the pineal gland of aging animals have been published. The pineal gland of the gerbil is especially interesting in respect to aging because of its progressive calcification with age, and this species has been considered as an excellent model for research on aging. Therefore, the aim of the present study was to examine the quantitative ultrastructure of pinealocytes of the gerbil in three different age groups. METHODS. Three groups of animals were included in the study: 1-month-old, 3-month-old, and 14-month-old. Cross-sectional areas of the pinealocyte and its nucleus and relative volumes of the following cell organelles: mitochondria, lysosomes, Golgi apparatus, granular endoplasmic reticulum and calcareous concretions as well as the number of dense-core vesicles and "synaptic" ribbons were analyzed. RESULTS. No age-dependent changes were observed in the size of pinealocytes and their nuclei. The relative volume of mitochondria and the number of dense-core vesicles increased progressively with age, and that of lysosomes was lowest in the 1-month-old animals and increased at age of 3 and 14 months, whereas a decrease in the relative volume of granular endoplasmic reticulum was observed in 3- and 14-month-old gerbils in comparison with 1-month-old animals. No difference was observed in relative volume of Golgi apparatus and in the number of "synaptic" ribbons. The most striking change was observed in the formation of calcareous concretion within the pineal with age. The pineal gland of 1-month-old gerbils was essentially devoid of these structures, their number and size in 3-month-old animals were moderate, and increased dramatically in 14-month-old animals. CONCLUSION. The ultrastructural features of the gerbil pinealocyte in all examined age groups point to high metabolic activity of these cells.

Journal Article↗

PubMedDate not supplied

Evaluation of ultrastructural changes in paranasal sinus mucosa after functional endoscopic sinus surgery in patients with chronic rhinosinusitis.

The purpose of this study was to compare the preoperative and postoperative ultrastructural changes of paranasal sinus mucosa in patients treated with functional endoscopic sinus surgery for chronic rhinosinusitis. Twelve patients undergoing functional endoscopic sinus surgery for the treatment of chronic rhinosinusitis were involved. The ethmoid sinus mucosa was sampled during the operation and approximately 6 months after the operation. The ciliated epithelium of sinus mucosa was evaluated with transmission electron microscopy. The samples were taken at the Otolaryngology Department of Istanbul University School of Medicine. Electron microscopic study was performed at the Histology and Embryology Department of the same University. Preoperatively, ciliated epithelial cells of the sinus mucosa of the patients showed degenerated ultrastructure with decreased number of cilia, cytoplasmic protrusions, cisternal dilatations of endoplasmic reticulum, and mitochondrial swellings. Remnants of degenerated cells and cellular separations at cell junctions were evident in the diseased epithelium. Goblet cells were frequent along the epithelial lining. Postoperatively, normal architecture and ultrastructure of the ciliated epithelium was restored. These observations showed that unlike other surgical operations, paranasal sinus mucosa can regenerate and the ciliated epithelium can return to normal after functional endoscopic sinus surgergy.

Adult↗

PubMed1975

[Changes in the ultrastructure of the chloride cells of sturgeon during adaptation to a hypertonic medium].

Alterations in the ultrastructure of chloride cells of young sturgeons Acipenser guldenstadti Brandt in the process of adaptation to hypertonic medium (S=105%) were under study. In the process of this adaptation thread-shaped long mitochondria became shorter, their random position was substituted by orientation in parallel to the axis of the cell. The amount of mitochrondria increased. A great number of vacuoles appeared in the cytoplasm. The character of the endoplasmic reticulum changed. The obtained data on the ultrastructure of chloride cells of the sturgeon confirm and supplement earlier light microscopy investigations of chloride cells of the sturgeon. The changes of the ultrastructure of chloride cells are interpreted as functional and adaptational ones.

Adaptation, Physiological↗

PubMed2001

Ultrastructure of the tunica albuginea in congenital penile curvature.

PURPOSE: We investigated the ultrastructure of the tunica albuginea in individuals with congenital penile curvature to explain the pathology of this disease. MATERIALS AND METHODS: Included in our study were 15 patients 17 to 24 years old with congenital penile curvature. Study material consisted of samples of the tunica albuginea excised from the greater curvature of the corpus cavernosum during surgical correction. Control samples were obtained from the lesser curvature on the side opposite the study material during the same operation. The 2 types of tissue were analyzed using transmitter electron microscopy. RESULTS: Ultrastructural examination of the control material revealed numerous collagen fibers that were homogenous in size and organization on cross section. Periodic striation was typical in collagen that produced fibers. In the study group the tunica albuginea structure had a chaotic pattern of collagen fibers that formed bundles with disrupted 3-dimensional organization. Diameter of the fibers differed greatly on cross section. We observed periodic widening and fragmentation of collagen fibers with the complete disappearance of striation and transformation into electron dense, fibrous granulated material. Disrupted fibroblasts without cell membrane and cellular organelles between collagen fibers were also visible. There was elastin accumulation without any morphological differences in the control and study groups. CONCLUSIONS: Our results show that ultrastructural changes in the tunica albuginea may cause congenital penile curvature, possibly by altering mechanical properties.

Adolescent↗

PubMed1975

Ultrastructure of gonadoblastoma.

We examined, ultrastructurally, gonadoblastomas from two phenotypic females with a 46,XY and 46,XY/45, XO genotype, respectively. Ultrastructurally, germ cells of gonadoblastoma resembled immature gonocytes; it was not possible to classify them into exact developmental stages given for normal fetal testes or ovaries. In the dysgerminomatous part of the first tumor, germ cells showed ultrastructural signs of differentiation comparable to abortive spermatogenesis as seen in testicular but not ovarian dysgerminosa. The sex cord cells resembled either Sertoli, granulosa, or ovarian stromal cells. The stroma surrounding the epithelial nests resembled the ovarian stroma and contained interstitial cells like Leydig or ovarian hilar cells or both. The epithelial nests of gonadoblastoma were surrounded by laminar multilayered basement membranes. The hyaline masses inside the tumor nests were composed of the same material.

Adolescent↗

PubMedDate not supplied

[Ultrastructural changes in gastroduodenal mucosal cells in patients with perforating ulcer and effect of serotonin adipinate on their postoperative rehabilitation].

Consideration is given in the paper to the state of the mucosal cell ultrastructure in the gastroduodenal zone in patients with perforating ulcer. Apparent inflammatory-degenerative type ultrastructural alterations have been found to be precent in the gastric and duodenal mucous coat in the zone of perforating ulcer. The above alterations are noted to persist by day 10 in these postsurgical patients having been administered conventional treatments. The use of serotonin adipinate promotes earlier restoration of the ultrastructural picture in the mucous coat of the gastroduodenal zone.

Adipates↗

PubMed2001

Histological and ultrastructural studies of rats exposed to carbaryl.

The aim of the study was to assess the general toxic effects of dermally applied carbaryl, based on histological and ultrastructural examinations of internal organs and to relate these effects to earlier own studies where 14C carbaryl was used for determining the pesticide penetration. The pesticide was applied in doses of 1/5 and 1/10 LD50, administered to the tail skin of male Wistar rats 4 hours daily, for 4 weeks except Saturdays and Sundays. After the experiment, the animals were anaesthetized and the following organs were taken for histological study: brain, lung, heart, liver, kidney, skin from the site of exposure and skin from a place at least 2 cm distant from the exposure site. Lung, liver, kidney, heart and skin were used for ultrastructural studies. Dermal application of carbaryl resulted only in slight histological changes in skin, liver, brain and lung. Even in brain and liver, where large amounts of 14C carbaryl, compared to other organs (lung, kidney, heart), where the intensity of histologic changes was earlier stated to below. Ultrastructural changes were observed in skin, liver, lung, heart and kidney.

Administration, Cutaneous↗

PubMed1975

Epithelial autolysis during implantation of the mouse blastocyst: an ultrastructural study.

An ultrastructural investigation was made of cell death in the uterine epithelium during the implantation of the mouse blastocyst. Cell death occurs in two phases: (i) early individual cell death, and (ii) later general cell death. Individual dead epithelial cells are phagocytosed and digested by trophoblast cells. At 95 h post coitum (p.c.) there are 1-4 dead cells; at 105 h and 113 h, 6-8 dead cells, and at 116 h, 2-3 dead cells. No lysosomal involvement could be identified in the death of these cells. The general breakdown of the uterine epithelium around the implanting blastocyst is first recognizable at the ultrastructural level at 113 h p.c., and continues until the adjacent deteriorated epithelium has been phagocytosed by the trophoblast cells at 119 h p.c. Ultrastructurally, from 113 h p.c. cytoplasmic portions of epithelial cells are trapped within cytosegrosomes, and there is an increase in size of the dense lysosomal bodies found in viable epithelial cells at 105 h p.c. The dense bodies, which are positively stained for acid phosphatase enzyme at 105 h p.c., increase in diameter approximately 3-5 times between 105 h p.c. and 119 h p.c. These results provide evidence of intracellular digestion of small portions of the cytoplasm possibly through the formation of cytosegrosomes which then fuse with residual bodies already present. Thus the evidence favours a process of autolytic breakdown of the uterine epithelium around the implanting blastocyst.

Animals↗

PubMed2001

Vital and ultrastructural changes in dog spermatozoa during cyopreservation.

The exact nature of cryo-injury to dog semen and the stage of cryopreservation at which it occurs have not been evaluated fully and were investigated in the present study. Semen samples were examined immediately before and after addition of semen extender, cooling and freeze-thawing in a Tris-based medium. Vital and ultrastructural assessments were made immediately after each treatment and after incubation for 4 h at 39 degrees C after each treatment. Addition of semen extender produced no significant ultrastructural changes in spermatozoa; however, cooling resulted in an immediate increase in the number of acrosomal abnormalities and a subsequent decrease in sperm viability. Freeze-thawing caused both an immediate and a delayed decrease in sperm viability. This effect may have been an exacerbation of the effects of cooling as many acrosomal abnormalities were present or it may have been the result of initially unrecognized damage. Cooling and freezing of dog spermatozoa may have both immediate and delayed effects on the ultrastructure of spermatozoa. The immediate effects of cooling and freezing may either kill spermatozoa or render them incapable of fertilization by damaging the acrosome, whereas delayed effects may reduce sperm longevity by altering plasma membrane structure.

Acrosome↗

PubMed1999

[The study of ultrastructure of retinal pigment epithelium of transplantation].

OBJECTIVE: To investigate the ultrastructure of retinal pigment epithelium (RPE) for the base of clinical application. METHODS: Pigmented rabbit RPE was transplanted to the subretinal space of 10 unpigmented rabbits by internal route. The ultrastructure of transplanted RPE cells were observed by electron microscopy. RESULTS: The transplantation of RPE was successful. It was shown that the transplanted cells had polarity and attached to Bruch's membrane to form basal infoldings, and the relationships between transplanted cells and the host photoreceptors were also seen. CONCLUSIONS: The internal approach is a practical and useful method for transplantation of RPE. The transplanted RPE can vitalize, perform metabolism and form some normal ultrastructure.

Animals↗

PubMed2001

Immunocytochemical localization of NOVH protein and ultrastructural characteristics of NCI-H295R cells.

In this study we present biochemical and immunocytochemical results on NOVH protein secretion and localization in NCI-H295R cells, as well as results on the ultrastructural characteristics of NCI-H295R cells. NCI-H295R cells were characterized by small quantities of rough and smooth endoplasmic reticulum, many free ribosomes, large nuclei with prominent nucleoli, numerous elongated mitochondria, a few Golgi complexes, and a small number of lipid droplets. Large numbers of coated pits and coated vesicles were present, but no secretory granules or exocytotic profiles were seen. Best ultrastructural preservation of NCI-H295R cells was achieved when fixation was done directly on the culture dishes and the cells were detached by scraping. Our biochemical results showed that NCI-H295R cells secreted large amounts of NOVH protein. The immunocytochemical localization of NOVH protein showed that the protein was localized in the cytoplasm, the plasma membrane and the nuclear envelope. This localization pattern, along with the ultrastructural and biochemical findings raise interesting questions on the function(s) and the mode of secretion of NOVH protein.

Adrenal Cortex Neoplasms↗

PubMed1975

Gentamicin nephrotoxicity in rats. I. Acute biochemical and ultrastructural effects.

This investigation characterizes the acute biochemical and ultrastructural alterations within the rat kidney following the single injection of 10, 40, 80, or 160 mg. of gentamicin per kilogram of rat weight. Gentamicin was given intraperitoneally and rats were killed 80 minutes later. To assess a possible inhibitory effect upon protein synthesis 3H-leucine was injected 20 minutes postantibiotic and renal cortex was assayed for whole tissue and the protein fraction amino acid uptake. To exclude the possibility of gentamicin-induced lysosomal membrane instability with subsequent release of acid hydrolases, the activity of acid phosphatase was assayed in the supernatant and the residue of cortical homogenates containing the lysosomal fraction. Ultrastructural changes were concomitantly studied. To determine the intracellular localization of gentamicin, levels of the antibiotic were measured in subcellular fractions of cortical homogenates obtained from rats 2 hours following a single subcutaneous injection of 20 mg. of gentamicin per kilogram of rat weight. No gentamicin-induced alterations either of protein synthesis or of acid phosphatase distribution were demonstrated. Ultrastructural changes were most marked at 160 mg. per kg. consisting mainly of dilation of the endoplasmic reticulum, altered mitochondria, and increased cytosegresomes. Significant quantities of gentamicin were distributed within the nuclear, mitochondrial, and microsomal fractions. These studies indicate that although cytoplasmic alterations are prominent within the proximal tubular epithelial cells, they are not likely the result of either inhibition of protein synthesis or release of acid phosphatase from lysosomes.

Acid Phosphatase↗

PubMed1998

[A study on lens epithelial cell ultrastructure in rhesus monkey cataract].

OBJECTIVE: To investigate the ultrastructure of lens epithelial cells of normal eyes and cataractous eyes in rhesus monkeys. METHODS: Anterior capsules were taken from 4 normal lenses and 4 cataractous lenses of rhesus monkey eyes, and the samples were observed under transmission electron microscope. RESULTS: The ultrastructure of the cataractous lens epithelial cells changed obviously. Mitochondria with disappearance of crista were swollen, and vacuolar. Hollow cell with a single large vacuole in the cytoplasm could be seen. The cytoplasm presented dissolution. Cells were swollen and damaged, even cell membrane disruption could be seen. Karyopyknosis, nuclear deformity, disappearance of perinuclear cistern and nuclear pores could be found. The heterochromatin was concentrated and aggregated at the nuclear periphery. CONCLUSIONS: The ultrastructural changes of the lens epithelial cells in monkey cataractous lens are similar to that in human cataractous lens. Rhesus monkey cataract may be a suitable experimental model to investigate the formation of human cataract.

Animals↗

PubMed1975

Ultrastructure of gonadal ridge in male and female pig embryos.

Pig embryos aged 21-22 days (d) obtained from artificially inseminated sows for an ultrastructural study of the development and sex differentiation of the gonadal ridge. The chromosomal sex of the embryos was identified by a chromosome analysis. At the age of 21 d the gonadal ridge consisted of three different tissues: the surface epithelium, the primitive cords, and the mesenchyme. The surface epithelial cells contained elongate mitochondria with lamellar cristae, granular endoplasmic reticulum (GER), the Golgi complex, free polysomes, coated vesicles and fine filaments. The epithelium was continuous with the primitive cords, which were composed of ultrastructurally similar cells. The epithelial basal lamina followed the cord surface, but covered it incompletely. Primordial germ cells (PGC) were located under the surface epithelium in the mesenchyme and in the cords. The nucleus with a prominent nucleolus, and the large mitochondria were round. The cytoplasm contained a pair of centrioles, the Golgi complex, solitary lamellae of the GER, free polysomes, lipid droplets and some coated vesicles. The PGC entered the gonadal cords before these were surrounded by the continuous basal lamina. A day later (22 d) the number and length of the cords were increased. The PGC were more frequent and seen also in deeper layers. All the structures studied at the age of 21-22 d showed that the gonadal ridge also at the ultrastructural level is at the sexually indifferent stage.

Animals↗

PubMed2002

A qualitative ultrastructural study of the hypocontractile detrusor.

PURPOSE: It has been proposed that precise and specific ultrastructural patterns exist in the dysfunctional human detrusor. We evaluated ultrastructural changes in the hypocontractile detrusor and examined the technique of detrusor muscle biopsy and its clinical application. MATERIALS AND METHODS: After clinical and urodynamic evaluation 19 male and 2 female patients with severe hypocontractility were entered into this prospective study. All patients had a post-void residual urine volume of consistently greater than 300 ml. and were classified as weak or very weak according to the Schäfer nomogram. Multiple biopsies were obtained with the patient under general anesthesia using the cold cup technique. Subsequent specimens were processed for electron microscopy using standard methods. Biopsies were also obtained from 6 controls with normal voiding parameters. RESULTS: Cold cup detrusor biopsy provided muscle of sufficient quality for detailed electron microscopic analysis in 26 of the 27 specimens obtained. Previously described criteria of the degeneration pattern were present in all cases of severe hypocontractility. These criteria include widespread disruptive muscle cell profiles with sarcoplasmic vacuolation, disruption of cell organelles and ultimately cell lysis. These features were evident in more than half of the randomly studied fields. In addition, 7 patients had an indistinct muscle fascicle cell arrangement with excessive deposits of collagen and elastic fibers between widely separated muscle cells and in the interstitium. It was suggested that these features represent the hyperelastosis pattern in the chronically over distended bladder. These morphological appearances were not present in any controls. CONCLUSIONS: This early study would appear to support a morphological basis for detrusor hypocontractility and it reinforces the feasibility of electron microscopy as a potential diagnostic tool. The hypocontractile detrusor has distinct ultrastructural appearances that are easily distinguishable from those of the normal age matched detrusor.

Adult↗

PubMed2000

[Effect of prolonging time for sampling on preservation of ultrastructure during the specimen preparation].

The ultrastructural change of rat liver, which was not immediately fixed after separation from the animal, was observed under electron microscope. The results showed that the ultrastructure of hepatocytes still satisfied the needs for diagnostic electron microscopy if the isolated livers were soaked in normal saline for 30 minutes, at room temperature, or placed in 4 degrees C refrigerator for 60 minutes, then they were fixed. After the isolated samples were put at room temperature for over 30 minutes, ultrastructure of hepatocytes were damaged so severely as to lose value for observation under electron microscope.

Animals↗

PubMed1975

[Ultrastructure of nephridial systems in cyclophyllidean cestoda: Catenotaenia pusilla (Goeze, 1782), Hymenolepis diminuta (Rudolphi, 1819) and Inermicapsifer madagascariensis (Davaine, 1870) Baer, 1956].

Electron microscopic study of nephridial systems in three cyclophyllidean cestodes indicates a resemblance in their ultrastructure. The walls of longitudinal, transverse and collecting ducts show a very similar pattern of organization. The surface of the anucleate epithelium lining the ducts is developed into microvilli. A relatively thick layer of fibrillar tissue underlies the basal membrane of the microvillar epithelium. The nucleated portions or "pericaryons", situated between the parenchymal cells, are directly connected with epithelium by cytoplasmic prolongations. The canalicular lumen extends through a single series of cells curved into a ring. The epithelial surface of the canalicular wall is developed into short, densly staining microvilli and the immediately underlying fibrillar tissue appears very compact. The cilia were never observed in any of the above ducts. The ultrastructure of protonephridia proper is comparable with those already described in other cestodes. There is a close association between the flame-cell and the cancalicular ending, enlarged into a nephridial funnel. A single row of nephridial rods of the flame-cell is surrounded by a row of digitiform prolongations of the nephridial funnel border. The prolongations alternate with the rods and their interlocking pattern appears clearly in cross-sections. A series of minute pores or "nephrostomes" providing a direct contact between the nephridial chamber and intercellular space of the paranchyma was shown. The problem of classification and definition between the "closed" protonephridia and open metanephridia is discussed. The structural unity of protonephridia in different groupes of Platyhelminthes is reviewed. The different number of flagella within the "flames" of different cestodes is compared and analyzed. The ultrastructural characteristics of duct-wall epithelium provides some confirmation of its high metabolic activity.

Animals↗