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PubMed1977

A study of mammalian intrafusal muscle fibres using a combined histochemical and ultrastructural technique.

A direct correlation of the histochemical and ultrastructural properties of intrafusal muscle fibres has been achieved by cutting frozen serial sections for histochemical applications (15 micron thick sections) and for electron microscopy (60 micron thick sections) in a repeating sequence. Three types of intrafusal fibre were recognized, including two types of nuclear-bag fibre, designated bag1 and bag2. In addition to histochemical and ultrastructural differences, the three types of fibre differed in length and diameter. Regional variations of histochemical and ultrastructural properties were found. The results are compared with previous attempts to correlate histochemical and ultrastructural properties of intrafusal muscle fibres based on indirect methods.

Adenosine Triphosphatases↗
PubMed1992

Effects of macrolides on ultrastructure of Staphylococcus aureus during postantibiotic phase.

The postantibiotic effects (PAEs) of macrolide antibiotics, such as midecamycin acetate (Miocamycin, MOM), erythromycin (EM), josamycin (JM) and clarithromycin (CAM), on Staphylococcus aureus and the ultrastructure of the pathogen during the postantibiotic phase were investigated. After exposure to 2 x MIC for 2 h, MOM showed the longest PAE of 3.9 h, while EM, JM and CAM showed PAE durations 1.2, 2.5 and 1.9 h, respectively. On examining the serum levels of these agents in man, the longest PAE of 2.4 h was induced by exposure to MOM. JM and CAM induced PAEs for durations of 1.4 and 1.3 h, but EM hardly induced the PAE. The ultrastructure was examined by transmission electron microscopy, and thick cell walls with an undulating outer layer and a multiple thick cross-section were observed for 4 h after exposure to 2 x MIC of MOM for 2 h. After exposure to 2 x MIC of EM, JM and CAM for 2 h, ultrastructural changes were observed for 1, 2 and 2 h, respectively. The size of these cells was about 1.5 to 2 times larger than the normal cells. Ultrastructural changes in S. aureus were observed during the PAE phase of each macrolide.

Anti-Bacterial Agents↗
PubMed1992

The orbital glands of the chelonians Pseudemys scripta and Testudo graeca: comparative histological, histochemical and ultrastructural investigations.

The orbital glands of the chelonians Pseudemys scripta and Testudo graeca were investigated at the histological, histochemical and ultrastructural levels. Four acinar cell types were seen in the harderian gland of P. scripta on the basis of histochemical reactions and ultrastructure. Secretory granules were of 2 types, one showing moderate electron density with an electronlucent core, the other being smaller and more osmiophilic with an electron-dense core. In the harderian gland of T. graeca only 2 glandular cell types were found; one type contained secretory granules with a dense core surrounded by a wide zone of lower density. Acinar cells of the anterior lacrimal gland in both species were of 2 types, one being of mucous type. In the harderian gland and in the lacrimal gland of both species, one cell type appeared not to be involved in the secretion of organic material. These cells contained numerous tightly packed mitochondria among which were abundant clumps of glycogen; the cell membrane was specialised at both edges. This cell type was similar ultrastructurally to the 'salt cells' described in the salt-secreting glands of various marine vertebrates, i.e. of the cells involved in transport processes. These combined histological, histochemical and ultrastructural studies have allowed us to distinguish orbital glands. In the past, the harderian and lacrimal glands in chelonians have often been mistaken for one another.

Anatomy, Comparative↗
PubMed1992

The effect of radix Salviae miltiorrhizae on the changes of ultrastructure in rat brain after cerebral ischemia.

The effect of RSM on ultrastructural alterations of the cortical, hippocampal and caudate neucleus areas brought about by forebrain ischemia in rats were studied. In both RSM-treated and saline-treated groups the ischemic damage was detected in nearly all animals three hours after bilateral common carotid artery ligation, while it was much more mild in RSM-treated animals. The ultrastructural changes consisted of swollen mitochondria, partial loss of cristae, dilatation of rough endoplasmic reticulum and Golgi's complex. In addition, some dark neurons were present, capillary endothelial cells and processes of astrocytes were swollen and active pinocytosis appeared in the endothelial cells. Their presence was most severe in the hippocampus region and the least in the caudate nuclear area. No ultrastructural changes exhibited in the sham-operated animals. The findings of the present experiment demonstrate that RSM can reduce ultrastructural abnormalities of cerebral ischemia and are also direct evidence of the protective effect of RSM on cerebral ischemia.

Animals↗
PubMed2002

Hepatic stress gene expression and ultrastructural features under intermittent Pringle manoeuvre.

BACKGROUND: Intermittent Pringle manoeuvre resulted in less blood loss and better preservation of liver function when it was applied for fewer than 120 minutes. The mechanism of better preservation of liver function under intermittent Pringle manoeuvre at molecular level remains unclear. Furthermore, the ultrastructural features in the liver with chronic diseases under intermittent Pringle manoeuvre have not been studied. The aim of the study is to investigate the expression of stress genes and ultrastructural change of the liver under intermittent Pringle manoeuvre. METHODS: From July 1995 to February 1998, 131 patients underwent hepatectomy for liver tumours (61 patients without Pringle manoeuvre and 70 patients with intermittent Pringle manoeuvre). Twenty-five patients (15 with Pringle manoeuvre and 10 without Pringle manoeuvre) were included in the study of hepatic stress gene expression during hepatectomy. Twenty-two patients (18 patients with intermittent Pringle manoeuvre and four patients without Pringle manoeuvre) were randomly assigned for electron microscopic examination. RESULTS: For the expression of stress genes, both the heat shock genes (HSP 70A and HSC 70) and acute phase genes (TNF-alpha and interleukin-6) were detected simultaneously in the patients with or without intermittent Pringle manoeuvre. The patients under intermittent Pringle manoeuvre had relatively higher mRNA levels of heat shock gene 70 family, which is related to intracellular repair and protection. Induction of TNF-alpha and interleukin-6 genes, which contributed to ischaemia-reperfusion injury and postoperative complication, was not found in the patients under intermittent Pringle manoeuvre. Under the electron microscopy, the hepatic ultrastructure was well maintained under intermittent Pringle manoeuvre whatever the liver status, even when the accumulated ischaemic duration was extended to 120 min. CONCLUSION: Intermittent Pringle manoeuvre induced relatively higher expression of heat shock genes, which are related to intracellular homeostasis, and is consistent with the well maintenance of liver ultrastructure.

Gene Expression↗
PubMed1992

Interdigitating cells in the rat thymus during cyclosporin A treatment: ultrastructural observations.

Major Histocompatibility Complex (MHC) class II-positive cells are almost completely absent in the rat thymic medulla after cyclosporin A (CsA) exposure. This phenomenon has been related to alterations in the medullary interdigitating cells (IDCs), representing either down-modulation of RT1 class II antigen on persistent IDCs, or actual disappearance of IDCs. To resolve this issue, we performed an ultrastructural study of the rat thymic medulla during CsA treatment (15 mg/kg body weight/day CsA subcutaneously for 7 to 14 days). At day 7 after exposure, only very few IDCs could be identified. They showed an abnormal ultrastructural morphology as judged by inconspicuous membrane interdigitations and lack of Birbeck granules. At day 14, the number of IDCs was larger. At this time, the IDCs had a normal ultrastructure, except for the almost complete absence of Birbeck granules. We conclude that CsA causes an initial depletion of IDCs from the thymic medulla. The ultrastructural morphology of the few IDCs present suggests an immature character. New IDC immigrants appear in the medullary area already during CsA treatment, indicating early recovery.

Animals↗
PubMed2003

Effect of L-arginine on overhydration and ultrastructure preservation of rat's heart exposed to cold cardioplegic ischaemia.

UNLABELLED: ISCHAEMIA: Reperfusion damage causes injury both cardiomyocytes and endothelial cells. Loss of endothelium function and heart cells degeneration can be essential for deterioration of postoperative efficiency of heart and in this way can threaten patients' life. OBJECTIVE: How addition of L-arginine to cardioplegic solution influences development of ultrastructural degeneration indications of rat's heart exposed to cold cardiolegic ischemia. METHODS: The research was conducted on isolated heart model of 56 rats, divided into seven equal groups. The hearts were prepared with modified Neely's method and were perfused with the use of apparatus in accordance with modified Langedorf's method. The research was carried out in order: initial perfusion of the non-working and working heart, perfusion with cardioplegic solution, cold cardioplegic arrest with or without addition of L-arginine. RESULTS: In the microscopic preparations of rat's heart in the control group (P) numerous focal performing contraction nodes were found. Intumescent vessels' endothelium included a large number of pinocytal vesicles. In the ultrastructural examination of group DI heart preparations there were less contraction nodes than in control group. The widening of endoplasmatic reticulum's channels and system T was essentially smaller comparing with group P. Less widening of perivascular zone and less number and size of pinocytal vesicles were also observed. In group 2 further decreasing of contraction nodes number was revealed. The structure of capillary was preserved and number of pinocytal vesicles was still decreasing. Further standardization of ultrastructural picture of cardiomyocytes and perivascular zone was found in group 3. CONCLUSION: In control group (P) microscopic degeneration indications of rat's heart were the most intensified. Addition of L-arginine to cardioplegic solution influenced decreasing of intensification of heart degeneration indications. Increasing of L-arginine doses added to cardioplegic solution positive correlates with protective effect of L-arginine on heart ultrastructure.

Animals↗
PubMed2003

[Ultrastructure analysis and cytokines expression of orbital fibroblasts in the patients with thyroid-associated ophthalmopathy].

OBJECTIVE: To analyse the ultrastructure and cytokines expression from cultured orbital fibroblasts (OFs) in the patients with thyroid-associated ophthalmopathy (TAO). METHODS: Primary cultured OFs were obtained from 5 patients with TAO and 4 normal control subjects, some of subcultured OFs were treated by patients' serum with active TAO. Ultrastructures of OFs were observed by transmission election microscope. The cytokines in cultured supernatant were detected by enzyme linked immunosorbant assay (ELISA). RESULTS: There were no significant differences of ultrastructure of OFs from TAO patients and normal subjects. Nucleoli enlargement, microvillus prolongation and increase of endoplasmic reticular of OFs were detected after maintaining in culture. The IL-1, TNF-alpha and IFN-gamma were found in supernatant of OFs treated by patients' serum. IL-1 was found in supernatant of OFs in TAO patient and control subjects, and the IL-1 level of former was higher than the controls. CONCLUSION: There are no significant differences in ultrastructure of OFs from patients with TAO and normal subjects. The OFs treated with the serum of TAO patients showed proliferation and increasing cytokines secretion.

Cytokines↗
PubMed2004

[Effect of selection techniques on chromosome and ultrastructure of human spermatozoa].

OBJECTIVE: To know the effect of different selection techniques on chromosome abnormality rate and the percentage of spermatozoa with relatively intact head ultrastructure in human sperm. METHODS: The selection techniques of swim-up, Percoll density gradient centrifugation and doule-flection tube were used to observe sperm chromosome abnormality rate, sex chromosomal ratio and the percentage of spermatozoa with relatively intact head ultrastructure. RESULTS: The sperm chromosome abnormality rate, sex chromosomal ratio and the percentage of spermatozoa with relatively intact head ultrastructure remained unchanged after the application of the three selection techniques(P > 0.05). CONCLUSION: The three selection techniques used in this study neither increase the damage to sperm ultrastructure nor exert effects on human chromosome.

Adult↗
PubMed2004

Ultrastructural analysis of granulocyte inclusions in genetically confirmed MYH9-related disorders.

BACKGROUND AND OBJECTIVES: MYH9-related disorders are autosomal dominant hereditary macrothrombocytopenias caused by mutations in the MYH9 gene. This gene encodes the non-muscular myosin heavy chain type II A (MHCIIA). Among these disorders, May-Hegglin anomaly (MHA), Sebastian syndrome (SS), and Fechtner syndrome (FS) are associated with different types of ribosome inclusions in granulocytes. FS also exhibits Alport-like manifestations: nephropathy, neurosensory deafness, and cataracts. The aim of our study was to assess the granulocyte inclusion ultrastructure in genetically confirmed MYH9-related disorders. DESIGN AND METHODS: Ten individuals were studied. All fulfilled the clinical and laboratory findings to be diagnosed as having an MYH9-related disorder. The ultrastructure of 50 granulocyte sections for each patient was examined, and the percentages of the different types of inclusion were established. Mutations of the MYH9 gene were also analyzed. RESULTS: The patients were classified as having MHA if the inclusions contained parallel longitudinal filaments. If not, they were classified as having SS or FS. FS patients also showed Alport-like manifestations. In all syndromes we observed a wide variability of the inclusion ultrastructure. Moreover, a small number of inclusions typical of other syndromes was observed. A new cross-striated inclusion variant was identified in SS. A significant number of pure ribosome aggregates were identified in all syndromes. INTERPRETATION AND CONCLUSIONS: Like other MYH9-related traits, the variation and partial overlap in the inclusion ultrastructure could be attributed to specific changes in the polymerization, assembly, or stability of the MHCIIA. These changes might be associated with MYH9 gene mutations as well as with its heterogeneous expression.

Adult↗
PubMed2004

[Ultrastructure of the pinealocytes in rats exposed to light and radiation].

Changes in pinealocytes (PC) were analysed using quantitative electron microscopy in 240 adult male rats from first minutes up to 180 days after their continuous exposure to bright light (CLE) for 48 hours, X-ray irradiation (XRI) or their combination (CE). After CLE early changes of PC included the reduction of rough endoplasmic reticulum (RER), Golgi complex and synaptic ribbons. At 24 hours and 10 days PC secretory activity was increased, while their ultrastructural organization was normalized by 30-180 days. 10 days after XRI degenerative changes were detected in PC that included dilation, fragmentation and vacuolization of RER cisterns, mitochondrial swelling, appearance of large vacuoles and osmiophilic inclusions, increase in lysosome content. Volume density of mitochondria and RER was lower, while that of Golgi complex was higher than in control. PC ultrastructure was restored 30-180 days after XRI. Following CE, the changes in PC ultrastructural organization were more significant at all time interval studied than after the action of single factors. The results obtained indicate that CLE increased the extent of postradiation changes in PC ultrastructural organization during the early time intervals after XRI and at the peak of radiation sickness development.

Adaptation, Physiological↗
PubMed2004

Effect of myrrh extract on the liver of normal and bilharzially infected mice. An ultrastructural study.

In the present work, the efficacy of purified oloe-resin extract of myrrh derived from Commiphora molmol tree (commercially known as Mirazid) as a new, natural antischistosomal drug was investigated. The effect of myrrh on the ultrastructural profile of the non infected normal mice liver was also studied. Sixty male mice were used throughout this work and they were divided into 3 main groups (20 animals each): group I, non infected control animals, group II, infected animals and group III, infected animals treated with myrrh extract 8 weeks post infection (500 mg/kg body weight). The drug was given orally on an empty stomach after overnight fasting for five successive days. All animals were sacrificed after 12 weeks from the beginning of the experiment and small pieces of the liver were excised and prepared for ultrastructural study. The liver of the non infected animals which received myrrh extract (group IA) showed a more or less normal ultrastructural profile. Infected groups showed alterations of the ultrastructure of most of the hepatocytes with extensive intercellular fibrosis with abundant granulomas in the portal tract. In the infected treated group, most of the hepatocytes showed normal organelles with numerous microvilli extending into patent spaces of Disse. Marked reduction of granulomas in the portal areas and amelioration of intercellular fibrosis was also observed. On the basis of the observed results, it was concluded that myrrh extract has a promising antischistosomal non hepatotoxic activity.

Animals↗
PubMed1979

ULTRASTRUCTURAL ANALYSES OF STONE HEART SYNDROME AT ONSET AND SIX DAYS LATER FOLLOWING TOTAL SUPPORT OF THE CIRCULATION WITH A PARTIAL ARTIFICIAL HEART OR LEFT VENTRICULAR ASSIST DEVICE (ALVAD).

Ischemic myocardial contracture developed in a 21-year-old man following aortic and mitral valve replacement. The patient's circulation was supported totally for 6 days with an abdominal left ventricular assist device (ALVAD). Cardiac allografting was then undertaken. Samples of myocardium taken at the original operation and 6 days later at transplantation were analyzed ultrastructurally. At the onset of ischemic cortracture, left ventricular abnormalities included hypercontraction of myofibrils, loss of normal A-band and Z-band patterns, mitochondrial swelling with fusion of cristae, interfibrillar edema and glycogen depletion. Capillaries demonstrated swelling of endothelial cells and basement membrane disruption. Six days later, ultrastructural morphology showed further degeneration. The myofibrils remained hypercontracted, but were more fragmented. Degenerative changes in mitochondria were more advanced and calcium deposition in cristae was present. No glycogen was seen. The right ventricular myocardium exhibited significantly fewer ultrastructural abnormalities. The principal right ventricular changes were endothelial swelling and basement membrane disruption. Glycogen granules were present. Ischemic contracture affects the left ventricle more than the right, and the morphology becomes more abnormal with time. To our knowledge, this is the first instance wherein morphologic progressions of the ultrastructural alterations of ischemic contracture have been documented.

Journal Article↗
PubMed2004

Effects of Crest Whitestrips bleaching on subsurface microhardness and ultrastructure of tooth enamel and coronal dentin.

PURPOSE: To describe the complementary subsurface analysis of structural and ultrastructural effects of bleaching with Crest Whitestrips on enamel and coronal dentin METHODS: Human tooth enamel specimens were cycled through a daily regimen including salivary immersions and treatments with commercial tooth whitening gels containing hydrogen peroxide or carbamide peroxide. Treatments with hydrogen peroxide in Crest Whitestrips gel base were carried out for up to 70 hours bleaching (some five fold to the clinical exposure required to produce satisfactory whitening in bleaching strip systems as established by double blind placebo controlled clinical studies) [correction]. Following in vitro laboratory cycling, the teeth were cross sectioned and remounted for observation of microhardness and ultrastructural characteristics in subsurface regions. Ultrastructure was assessed by application of confocal laser scanning microscopy (reflection mode). RESULTS: Peroxide whitening compositions had no effects on subsurface microhardness of enamel or dentin, even under conditions of five fold overbleaching. Crest Whitestrips gel containing up to 6.5% hydrogen peroxide applied for periods up to 70 hours (five kit) overbleaching was found to produce no changes (at a lateral resolution of 200-300 nm) in observed subsurface enamel and dentin ultrastructure or architecture.

Analysis of Variance↗
PubMed2004

Ultrastructural evaluation of activated forms of microglia in human brain in selected neurological diseases (SSPE, Wilson's disease and Alzheimer's disease).

Activated forms of microglia were ultrastructurally evaluated in three neurological diseases of different aetiology (subacute sclerosing panencephalitis--SSPE, Wilson's disease and Alzheimer's disease). The occurrence of activated rod, ramified and amoeboid microglia was found in the investigated diseases. The widest ultrastructural variability of microglia was in SSPE, including the presence of mitotic chromosomes or centrioles in its cytoplasm, which indicates microglia proliferation. In the nuclei of activated microglia, some nuclear bodies with different structures were frequently seen, whereas lamellar structures (similar to developing Birbeck's bodies--pathognomonic to Langerhans-type dendritic cells) were observed in the cytoplasm. The activated forms of microglia with apoptotic features were found only in SSPE cases. Some apoptotic nuclei were filled with nucleocapsids of measles virus. In Alzheimer's disease, activated microglia was most frequently bound to senile plaques. Ramified microglia was in contact with amyloid fibrils, which penetrated its cytoplasm and reached the nuclear membrane and channels of rough endoplasmic reticulum, or was situated among dystrophic neurites. Rod microglia was found predominantly at the edge of senile plaques. In Wilson's disease, the ultrastructure of activated microglia showed mostly indirect forms between rod, ramified and amoeboid microglia. The microglia ultrastructure suggests that its morphological form may express functional involvement in the pathogenesis of a given disease entity.

Adolescent↗
PubMed2004

[Effects of ulinastatin on renal ultrastructure after ischemia-reperfusion in rats].

OBJECTIVE: To investigate the effect of ulinastatin on renal function and ultrastructure changes after renal ischemia-reperfusion in rats. METHODS: Acute ischemic renal injury model was established (45 min of bilateral renal ischemia and reperfusion for 24 h). Thirty Male SD rats were randomly divided into 3 groups: sham operation group (control group or group C, without renal ischemia), renal ischemia-reperfusion group (ischemia-reperfusion group or group I, without ulinastatin), renal ischemia-reperfusion and ulinastatin intravenous injection group (ulinastatin group or group U). BUN level, serum creatinine values and renal ultrastructure were measured. RESULTS: Serum creatinine (167 +/- 39) micromol/L and BUN concentration (21 +/- 7) mmol/L in group I were significantly higher than those in group U: serum creatinine (116 +/- 13) micromol/L and BUN concentration (14.1 +/- 2.6) mmol/L (P < 0.05). The renal ultrastructure was greatly injured in group I, meanwhile, it was obviously ameliorated in group U. CONCLUSION: Ulinastatin greatly improved renal function and provides remarkable protection on renal ultrastructure after ischemia-reperfusion of kidney in rats.

Animals↗
PubMed2004

[Ultrastructural characteristics of lipid droplets in rat adrenocortical cells from zona fasciculata-reticularis].

One day cultured adrenocortical cells from zona fasciculata-reticularis were used in morphological experiments. The electron-microscopic and imaging analysis methods were used for the investigation of intracellular ultrastructure of these cells. Experiments which conducted in control conditions, allowed us to allocate three types of cells which differed by ultrastructure of the mitochondria, lipid droplets, smooth endoplasmic reticulum and dense bodies. It was shown that lipid droplets with light and homogeneous matrix, met more often in cells with morphological attributes of high intensity of steroidogenesis. On the contrary, lipid droplets, with dark matrix and a dense edging, met more often in cells which having morphological attributes-of low intensity of steroidogenesis. Ionophore A23187 or adrenocorticotropic hormone application resulted in reduction of lipid droplets diameter and in simultaneous increase in density of their arrangement in cytoplasm. At the same time droplet matrix became light and homogeneous in all cells. Thus, the ultrastructure of lipid droplet matrix is sensitive to change of calcium ions concentration in cytoplasm. Processes which result in change of lipid droplet ultrastructure, probably, are connected to steroidogenesis, nevertheless, this question requires further investigation. The lipid droplets" ability to form morphological contacts with smooth endoplasmic reticulum, mitochondria, nuclear and cellular membranes is also discussed.

Adrenocorticotropic Hormone↗
PubMed1992

Malignant mesothelioma: cytologic diagnosis with histologic, immunohistochemical, and ultrastructural correlation.

The differential diagnoses of malignant mesothelioma in serous effusions include adenocarcinoma and reactive mesothelial cells. While several cytologic features are of predictive value in separating these entities, immunostaining and ultrastructural examination are important adjuncts that increase the diagnostic yield. Many of the cytomorphologic features can be correlated with immunohistochemical and ultrastructural findings. Most important among these is the ultrastructural demonstration of long, often branching microvillous processes in malignant mesothelial cells. Corresponding microvilli can be visualized by immunostaining for epithelial membrane antigen in both cell block preparations from effusions and biopsy specimens, allowing the identification of malignant mesothelioma. In addition, the circumferential distribution of these immunostained microvilli in cells dispersed in stromal connective tissue identifies them as malignant mesothelial cells, corresponding to the ultrastructural appearance of aberrant microvilli, which project through deficiencies in the basal lamina. These microvilli show interdigitation with stromal collagen fibers, a phenomena not observed in adenocarcinoma.

Adenocarcinoma↗