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PubMed1992

Ultrastructure of the guinea pig pancreas in acute hypercalcemia.

The effect of acute hypercalcemia on pancreatic ultrastructure and the ultrastructural localization of calcium during hypercalcemia were studied in the guinea pig pancreas. After 3 h of i.v. calcium infusion (0.6 mmol/kg/h), hypertrophy and distention of the Golgi apparatus and an increased number of condensing vacuoles were seen. At 6 h, vacuolar fusion and displacement of zymogen granules occurred. At 9 h, irregular distribution of zymogen granules, indentation of the nucleus with chromatin clumping, and inclusion of intact cell organelles were present. Disruption of the plasma membrane and release of cell organelles into the interstitial space were seen. Control animals receiving saline solution (0.9% NaCl) revealed normal pancreatic ultrastructure. The serum ionized calcium values were 0.65 +/- 0.36 mM in controls and 0.71 +/- 0.14, 0.79 +/- 0.21, and 1.22 +/- 0.50 mM at 3, 6, and 9 h of calcium infusion, respectively. The ultrastructural localization of calcium was performed with the pyroantimonate staining technique after 3 h of calcium and saline infusion. Large calcium deposits were found in calcium-treated animals along the plasma membrane and in the Golgi region. The findings indicate that calcium exerts a strong stimulatory effect that eventually leads to the degeneration of the pancreatic acinar cell.

Acute Disease↗
PubMed1996

Ultrastructural changes in spinal nerve roots induced by autologous nucleus pulposus.

STUDY DESIGN: Ultrastructural changes were analyzed by transmission electron microscopy in nerve roots exposed to autologous nucleus pulposus experimentally. OBJECTIVES: To assess if ultrastructural changes were present in areas with no light microscopic changes in nerve roots exposed to autologous nucleus pulposus in a pig model. SUMMARY OF BACKGROUND DATA: Previous analyses have shown that there is focal nerve fiber damage in nerve roots exposed to autologous nucleus pulposus in the pig. These changes could not fully explain the reduction in nerve conduction velocity seen in the same nerve roots. In the present study, the parts of the nerve roots that did not display breakdown of axons or myelin sheaths at the light microscopic level were analyzed regarding ultrastructural changes. METHODS: In a previous study, nucleus pulposus was harvested from a lumbar disc and placed epidurally onto the cauda equina at the sacrococcygeal level in pigs. Retroperitoneal fat was used as control. After 1, 3, and 7 days, the nerve roots were excised and processed for light microscopy. Parts of the nerve roots that appeared normal at the light microscopic level were further processed for the present electron microscopic examination. RESULTS: Significant ultrastructural changes, such as expansion of the Schwann cell cytoplasm and intracellular edema with vesicular swelling of the Schmidt-Lanterman incisures, were observed in nerve fibers with normal axons. Although present after nucleus pulposus and control application, the changes were more pronounced after the application of nucleus pulposus. CONCLUSIONS: Epidural application of autologous nucleus pulposus without any pressure may induce not only nerve function impairment but also axonal injury and significant primary Schwann cell damage with vesicular swelling of Schmidt-Lanterman incisures. However, because axonal and Schwann cell changes affected only part of the nerve fibers, further causes of the impaired nerve conduction need to be determined.

Animals↗
PubMed1997

An ultrastructural study of calcitonin gene-related peptide-immunoreactive nerve fibers innervating the rat posterior longitudinal ligament. A morphologic basis for their possible efferent actions.

STUDY DESIGN: The present study investigated ultrastructural characteristics of calcitonin gene-related peptide-immunoreactive nerve fibers in the posterior longitudinal ligament of the rat lumbar spine. OBJECTIVES: To provide a morphologic basis for assessment of the afferent and, in particular, efferent functions of calcitonin gene-related peptide immunoreactive nerves in the posterior longitudinal ligament and their eventual role in degenerative spondylarthropathies and low back pain. SUMMARY OF BACKGROUND DATA: Previous studies using light-microscopic localization of sensory neuronal markers such as calcitonin gene-related peptide have reported the presence of sensory fibers in the supporting structures of the vertebral column. Meanwhile, accumulating research data have suggested efferent properties for calcitonin gene-related peptide, i.e., a trophic action that alters the intrinsic properties of target cells not through transient action of synaptic transmission, but through long-lasting signal transmission by the secreted neuropeptides. To verify such trophic, paracrine actions of the calcitonin gene-related peptide-containing fibers in the posterior longitudinal ligament, however, ultrastructural details of the terminals and their spatial relationship to their eventual target structures have to be elucidated. METHODS: Rat posterior longitudinal ligaments were stained immunohistochemically for calcitonin gene-related peptide. Light-microscopic analysis of the semithin sections facilitated subsequent electron microscopy of specific sites of the posterior longitudinal ligament to determine ultrastructural details and nerve fiber-target relationships. RESULTS: The rat lumbar posterior longitudinal ligament was found to be innervated by two distinctive calcitonin gene-related peptide immunoreactive nerve networks. In immunoelectronmicroscopy, the fibers of the deep network had numerous free nerve endings, whereas those of the superficial network showed spatial associations with other non-calcitonin gene-related peptide immunoreactive components of the network. In both systems, naked axons not covered by the Schwann cells made close spatial contact with smooth muscle cells: of blood vessels and resident posterior longitudinal ligament fibroblasts. CONCLUSIONS: The ultrastructural characteristics of the innervation of the rat posterior longitudinal ligament would be compatible not only with a nociceptive function, but also with neuromodulatory, vasoregulatory, and trophic functions, as has already been established in some visceral organs.

Animals↗
PubMed2002

Ultrastructural characteristics of distal duodenum mucosa in patients with cirrhosis.

OBJECTIVES: Morphological abnormalities observed by light microscopy, such as oedema or vasodilatation, have been described in intestinal mucosa of patients with cirrhosis, but no information is available regarding the ultrastructural characteristics of the intestinal epithelial layer. The aim of this observational study was to investigate the ultrastructural characteristics of the intestinal epithelial layer of duodenum mucosa in patients with cirrhosis. METHODS: Six patients with advanced cirrhosis and six control patients without liver disease were included in the study. Biopsies were obtained from the distal duodenum during upper diagnostic endoscopy, and ultrastructural characteristics were studied by means of electron microscopy. RESULTS: A distended interenterocyte space with intestinal epithelial cells closely attached by morphologically intact tight junctions has been observed in cirrhotic patients, together with shorter and wider microvilli than in the control subjects. CONCLUSIONS: The epithelial layers from cirrhotic patients show ultrastructural abnormalities. However, it is not known if the observed alterations are related to the presence of increased intestinal permeability or to bacterial translocation, which are frequently found in these patients.

Adult↗
PubMed2003

Digital three-dimensional reconstruction and ultrastructure of the mouse proximal tubule.

Mice are prime targets of experimental gene modification and have become object of an increasing number of biologic studies in renal physiology, development, and molecular biology. Phenotypic changes in response to gene modification require detailed information on normal structure. However, detailed analyses of normal mouse kidney structure and organization are lacking. This study describes the 3D organization and ultrastructural, segmental variation of the mouse kidney proximal tubule. A total of 160 proximal tubules in three C57/BL/6J mouse kidneys were analyzed on 800 serial sections from each kidney from the surface to the inner stripe of the outer zone of medulla. All tubules were reconstructed in 3D and visualized by interactive computer graphics. A quantitative ultrastructural analysis of the mouse proximal tubule at every 300 to 400 micro m was performed. The 3D representation revealed a distinct organization of the mouse proximal tubule, each occupying a separate domain within the cortex. Superficial proximal tubules have long straight parts converging into clusters within the medullary rays. Tubules originating deeper within the cortex become longer and increasingly tortuous. In the medullary rays, these are arranged in layers outside the clusters of more superficial tubules. In contrast to rat and human kidney, no major segmental variation in the ultrastructure of the proximal tubule was identified, and no parameters enabled definition of distinct segments in this strain of mice. In conclusion, significant new information on the 3D organization of the murine proximal tubule has been obtained. Quantitative, ultrastructural analyses of mouse proximal tubules reveal substantial differences compared with other species.

Animals↗
PubMed2003

Structural basis of neurogenic bladder dysfunction. I. Methods of prospective ultrastructural study and overview of the findings.

PURPOSE: We standardize procedures for ultrastructural study of detrusor smooth muscle and intrinsic nerves in neurogenic bladder dysfunction in the human, and present an overview of the findings. MATERIALS AND METHODS: The study included 18 female and 33 male patients 7 to 96 years old. They had neurogenic bladder dysfunction with hyperreflexia for less than 1 to 43 years, resulting from upper motoneuron lesions (spinal cord injury 25, brain disorder 17) or combined upper and lower motoneuron deficit (meningomyelocele 9). Endoscopic or open bladder biopsies were processed for ultrastructural study of detrusor smooth muscle and intrinsic neural elements. Qualitative morphologic criteria of muscle cell arrangement, degeneration and cell-cell contacts, as well as those of degeneration and regeneration of intrinsic neural elements are defined. RESULTS: Five biopsies from the brain disorder group had insufficient smooth muscle and were excluded from study. The remaining 46 biopsies were evaluated by electron microscopy, and all displayed the complete dysjunction pattern of detrusor overactivity. Most displayed degeneration and regeneration of intrinsic axons but disproportionately limited muscle cell degeneration, irrespective of detrusor contractility. The brain disorder group biopsies displayed many more ultrastructurally normal axons than the meningomyelocele and spinal cord injury group biopsies (median 33% versus 8% or less). CONCLUSIONS: Upper motoneuron neurogenic bladder dysfunction in humans is associated with intrinsic neuromuscular defects in the detrusor. Ultrastructural features of these defects suggest morphologic markers that not only may distinguish neuropathic from nonneuropathic bladder dysfunction, but also may point to the anatomical level of the neurogenic deficit.

Adolescent↗
PubMed1968

Studies on ultrastructure and purification of isolated plant mitochondria.

Sweetpotato mitochondria, that showed respiratory control, were studied with respect to ultrastructure. If fixed in media containing sucrose at 0.4 M, the cristae were dilated and the matrix was highly condensed. A more orthodox ultrastructural form was observed when the mitochondria were fixed in a medium containing sucrose at 0.25 M, i.e., the matrix was more expanded, the cristae were less dilated, and peripherally, the inner membrane element lay adjacent to the outer membrane element. These results are discussed in terms of a sucrose-accessible space (space between outer and inner membrane elements including intracristal space), and a space relatively inaccessible to sucrose (matrix). Ultrastructural shifts were not observed with change in metabolic steady state of the mitochondria. High resolution electron micrographs showed that the ultrastructure of sweetpotato mitochondria is very similar to that of animal mitochondria.Purity and homogeneity of mitochondrial fractions were followed both by phase-contrast and electron microscopy. Preparations from sweetpotato, using older methods, were relatively homogeneous with respect to particle type and size, whereas avocado preparations contained a high proportion of chloroplasts and cellular debris. A method of purification involving sucrose-density-gradient centrifugation was developed. Purified mitochondria exhibited respiratory control and appeared similar to unpurified mitochondria under the electron microscope.

Journal Article↗
PubMed1973

Ultrastructural transformations in bean inner mitochondrial membranes.

The ultrastructure of inner membrane-matrix mitochondria isolated from bean (Phaseolus vulgaris) shoots was examined in different metabolic states. Gross ultrastructural transformations analogous to the condensed-to-orthodox configurational changes reported in mammalian mitochondria are observed on transistion from nonrespiring to respiring metabolism. With the induction of oxidative phosphorylation, the particles remain in the orthodox configurational state. The reverse orthodox-to-condensed configurational changes observed in mammalian preparations does not occur. Optically monitored absorbancy studies with bean particles show a substrate-supported P(i)-induced swelling under the same conditions that induce the condensed-to-orthodox ultrastructural transformation. The swelling is associated with the net uptake of K(+) and P(i) as well as a small P(i)-induced respiratory stimulation. When phosphorylation is initiated with these swollen particles, the optically monitored volume remains unchanged. Thus a positive correlation exists between the ultrastructural configuration and the osmotic volume changes, which supports the conclusion that configurational changes reflect internal osmotic adjustments.

Journal Article↗
PubMed1977

Ultrastructure of the human dermal microcirculation. II. The capillary loops of the dermal papillae.

Electron microscopy was used to define the ultrastructure of the capillary loops in the dermal papillae of normal, eczematous, and psoriatic skin. Capillary loops were reconstructed from 1-mum plastic-embedded sections. Ultrathin sections were taken at 4- to 6-mum intervals for correlation with the thick sections. The capillary loops of normal forearm and elbow skin could be divided into two segments: an intrapapillary and extrapapillary portion. The intrapapillary portion had the ultrastructural characteristics of an arterial capillary--homogeneous-appearing basement membrane without bridged fenestrations. The ascending limb in the extrapapillary portion was also an arterial capillary and the descending limb in the same portion had venous characteristics--multilayered basement membrane. The intrapapillary arterial loop developed venous characteristics abruptly after the vessel left the dermal papilla proper. The capillary loops in acute nummular eczema were identical in ultrastructure to those of normal skin. Bridged fenestrations were found in one capillary loop in eczema but not in normal skin. By contrast, the intrapapillary capillary loops in psoriasis were venous capillaries which were characterized by bridge fenestrations and multilayered basement membrane. The ultrastructural features of the capillary loops and those of the microcirculatory segments in the horizontal dermal plexus should provide sufficient criteria for one to evaluate the nature of vascular abnormalities that occur in the upper dermis.

Adult↗
PubMed2004

Mitochondrial dysfunction and ultrastructural damage in the hippocampus during kainic acid-induced status epilepticus in the rat.

PURPOSE: Prolonged and continuous epileptic seizure (status epilepticus) results in cellular changes that lead to neuronal damage. We investigated whether these cellular changes entail mitochondrial dysfunction and ultrastructural damage in the hippocampus, by using a kainic acid (KA)-induced experimental status epilepticus model. METHODS: In Sprague-Dawley rats maintained under chloral hydrate anesthesia, KA (0.5 nmol) was microinjected unilaterally into the CA3 subfield of the hippocampus to induce seizure-like hippocampal EEG activity. The activity of key mitochondrial respiratory chain enzymes in the dentate gyrus (DG), or CA1 or CA3 subfield of the hippocampus was measured 30 or 180 min after application of KA. Ultrastructure of mitochondria in those three hippocampal subfields during KA-induced status epilepticus also was examined with electron microscopy. RESULTS: Microinjection of KA into the CA3 subfield of the hippocampus elicited progressive build-up of seizure-like hippocampal EEG activity. Enzyme assay revealed significant depression of the activity of nicotinamide adenine dinucleotide cytochrome c reductase (marker for Complexes I+III) in the DG, or CA1 or CA3 subfields 180 min after KA-elicited temporal lobe status epilepticus. Conversely, the activities of succinate cytochrome c reductase (marker for Complexes II+III) and cytochrome c oxidase (marker for Complex IV) remained unaltered. Discernible mitochondrial ultrastructural damage, varying from swelling to disruption of membrane integrity, also was observed in the hippocampus 180 min after hippocampal application of KA. CONCLUSIONS: Our results demonstrated that dysfunction of Complex I respiratory chain enzyme and mitochondrial ultrastructural damage in the hippocampus are associated with prolonged seizure during experimental temporal lobe status epilepticus.

Animals↗
PubMed2006

Early and late immunohistochemical and ultrastructural changes associated with functional impairment of the lachrymal gland following external beam radiation.

The aim of this study was to investigate scintigraphic, immunohistological and ultrastructural changes associated with radiation-induced dysfunction of the lachrymal gland in an established experimental animal model. Ten rabbits were randomized into two groups and used for the study; in the control as well as experimental group, the Schirmer-test, lachrymal gland scintigraphy, and immunohistological and ultrastructural investigations were carried out prior to irradiation and 72 h as well as 1 month after single-dose irradiation with 15 Gy. Seventy-two hours after irradiation, secretion reduction evaluated by the Schirmer-test was evident. At this phase, we could observe a decrease in the expression of alpha-SMA and a re-distribution of tenascin-C matrix. Ultrastructural changes of acinar and myoepithelial cells were noticed; simultaneously, disturbance in the primary (99m)TcO(4)- uptake as well as significant reduction of the lachrymal ejection fraction was assessed scintigraphically. These changes were still evident 1 month following irradiation but became less intensive. Single-dose irradiation with 15 Gy implicates a functional impairment of the lachrymal gland, which is associated with early immunohistological and ultrastructural alterations. These changes may represent objective surrogate parameters for radiogenic dysfunction and prerequisites for further investigations on radioprotection of lachrymal glands during radiotherapy of the periorbital region.

Actins↗
PubMed1984

Relationship between ultrastructure and receptor content of human primary breast cancer.

The ultrastructure of 47 primary breast cancers was studied. For each tumour, the characteristics of approximately 200 malignant cells were examined. Eleven features were scored from 1 to 3 and multivariate analysis showed that seven of these could be used to define an ultrastructural index of differentiation. Differentiation at the ultrastructural level was associated with the presence of steroid receptors. Differentiated tumoral cells contained oestrogen receptor and progesterone receptor in 81.8% and 66.7% of cases, respectively. Poorly differentiated cells contained oestrogen receptors in 50% and progesterone receptor in 14.3% of cases. Comparison of histological grading by the method described by Scarff, Bloom & Richardson with the ultrastructural index of differentiation showed a rather loose correlation which was not significant in this group of 47 patients. The authors conclude that differentiation at tissue or cellular levels yields differing information, only the latter being closely correlated with steroid receptor presence.

Adenocarcinoma↗
PubMed2005

Malignant melanoma with neuroendocrine differentiation: clinical, histological, immunohistochemical and ultrastructural features of three cases.

AIM: To document the clinical, histological, immunohistochemical and ultrastructural features of three malignant melanomas showing neuroendocrine differentiation. METHODS AND RESULTS: Three patients, two with primary cutaneous melanoma and one with nasal mucosal melanoma, subsequently developing or simultaneously presenting with metastatic malignant melanoma, were studied by conventional histological technique, immunohistochemistry of formalin-fixed paraffin-wax embedded tissues, and electron microscopy of epoxy-resin-embedded tumour tissue. Tumours showed either small cell or conventional malignant melanoma cell morphology. One of the three primary melanocytic lesions (the nasal melanoma) exhibited neuroendocrine differentiation immunohistochemically. All three metastatic malignant melanomas showed, in varying combinations, immunohistochemical and ultrastructural evidence for neuroendocrine differentiation: they were positive for the melanocytic markers, S100 protein, HMB-45, Melan-A and tyrosinase, and the neuroendocrine markers chromogranin, synaptophysin and neurofilament protein. Ultrastructural study in two of the metastases revealed neuroendocrine granules but no lattice-bearing melanosomes. CONCLUSIONS: The cases described are the most comprehensively investigated malignant melanomas showing neuroendocrine differentiation to date, and the first to document neuroendocrine differentiation ultrastructurally in these tumours. Malignant melanoma with neuroendocrine differentiation therefore needs to be recognized among the other, better known variants of malignant melanoma.

Adult↗
PubMed2005

A fast method to study the secretory activity of neuroendocrine cells at the ultrastructural level.

Cryo field emission scanning electron microscopy (cryo-FE-SEM) is a versatile technique that allows the investigation of the three-dimensional organization of cells at the ultrastructural level over a wide range of magnifications. Unfortunately, cryopreparation of the specimens for this technique remains cumbersome, in particular because ice crystal formation must be prevented during freezing. Here we report that a light prefixation with glutaraldehyde and incubation in glycerol as cryoprotectant or a high-pressure freezing approach are both excellent procedures for cryopreparation of animal cells to be used in combination with cryo-FE-SEM. Using the proopiomelanocortin-producing intermediate pituitary melanotrope cells of Xenopus laevis as a physiologically inducible neuroendocrine system, we compared the ultrastructural characteristics of inactive and hyperactive neuroendocrine cells. The overall quality of the ultrastructural images was comparable for the two cryopreparation procedures, although some fine structures were better conserved using high-pressure freezing. Melanotrope cells in a secretory inactive state contained numerous storage granules and a poorly developed endoplasmic reticulum (ER), while large amounts of rough ER were present in hyperactive cells. Thus, the cryo-FE-SEM approach described here allows a fast ultrastructural study on the secretory activity of neuroendocrine cells.

Animals↗
PubMed1995

Ultrastructural abnormalities with inclusions in Onuf's nucleus in motor neuron disease (amyotrophic lateral sclerosis).

This study describes an ultrastructural examination focused on motor neurons in Onuf's nucleus in the spinal cord of four control patients without neurological disease (45-70 years) and six motor neuron disease (MND) patients (38-79 years; duration 8 months-19 years) who showed no somato-vesical dysfunction. Prompted by recent studies suggesting some sphincteric motor neurons may succumb to MND, this study sought to determine whether the wider population of neurons in Onuf's nucleus display ultrastructural cytopathology which is normally undetectable in histological preparations. Spinal cords were removed 3-20 h after death, and 1 mm slices of cord rapidly fixed in modified Karnovsky medium were processed for both light- and electronmicroscopy. 'Control motor neurons' had intact neuronal and nuclear membranes. Nissl bodies chiefly comprised ordered structures of alternate lamellae of rough endoplasmic reticulum and arrays of polyribosomes. The Golgi complexes consisted of multilamellated curvilinear stacks of ER. No intraneuronal filamentous or Bunina body inclusions were observed, but occasional axonal spheroids were seen in the neuropil. In MND, histological evidence of sparing in Onuf's nucleus was associated with abnormal ultrastructure of the motor neurons. Some sphincteric neurons were atrophic, whereas in the others, Nissl bodies were reduced in number, showed loss of structural organization or comprised polyribosomal aggregates. Golgi complexes had disrupted lamellated organization or consisted solely of distended ER. Intraneuronal filamentous Lewy-body or skein-like inclusions and Bunina bodies were identified in Onuf's nucleus of three subjects (duration of MND 8 months-2 years). The results of the present study indicate that Onuf's nucleus is vulnerable in MND, and preservation of sphincter function with qualitative histological evidence of 'sparing' does not necessarily imply a corresponding lack of ultrastructural cytopathology in this nucleus.

Adult↗
PubMed1979

Ultrastructure of skin biopsy specimens in lysosomal storage diseases: common sources of error in diagnosis.

Common sources of error in the diagnosis of lysosomal storage diseases by ultrastructural examination of skin specimens have been identified in a series of biopsies from 72 patients. Four principal factors have emerged as leading pitfalls and sources of error in diagnosis. First, the skin biopsy technique itself may lead to alterations of normal skin ultrastructure. Second, artifacts may be produced during fixation and preparation of tissue for electron microscopy. Third, cellular organelles and structures normally present in human skin may be mistakenly interpreted as pathological. Fourth, the use of cultured skin fibroblasts for ultrastructural identification of storage material is often accompanied by artifacts induced in tissue culture and is not recommended. Recognition of these common problems may aid interpretation of the fine structure of skin abnormalities. Furthermore, when skin biopsy specimens are used as the primary source of diagnostic material, correlation of both skin ultrastructure and assay for specific lysosomal enzymes in cultured dermal fibroblasts will facilitate diagnostic accuracy.

Biopsy↗
PubMed2005

Tissue pool neutrophils of the bovine mammary gland: ultrastructural features during in vitro senescence.

The aim of the study was to verify whether the in vitro senescence process of tissue pool neutrophils of the bovine mammary gland is accompanied by similar changes of ultrastructure as typically occurs in in vivo conditions. The experiments were carried out in four clinically healthy, Holstein x Bohemian Red-Pied crossbred heifers aged 14-16 months. With the aid of transmission electron microscopy (TEM), scanning electron microscopy (SEM) and flow cytometry (FCM), neutrophil apoptosis in vivo was detected and during senescence it was monitored in vitro. The neutrophil apoptosis comprised three ultrastructurally different stages: (1) karyopyknosis, (2) zeiosis, and (3) apoptotic bodies. These stages were obvious in the apoptotic neutrophils both in vivo and in vitro. In addition to the common morphological signs, however, ultrastructural differences were also detected in apoptotic neutrophils in vitro. These in vitro ultrastructural differences mostly comprised hyper-vacuolation of the cytoplasm with mega-vacuoles and secondary necrosis of apoptotic neutrophils. Morphological features of apoptosis during in vitro senescence of tissue pool neutrophils of the bovine mammary gland were shown to be in close accordance with these in vivo signs.

Animals↗
PubMed1985

Ultrastructural changes of the bile secretory apparatus and bile ductule in experimental hepatitis B with neither apparent biochemical nor light-microscopic cholestasis.

An ultrastructural study on the hepatic bile secretory apparatus and bile ductules was carried out using liver biopsy specimens of six chimpanzees with experimental hepatitis B. Although biochemical cholestasis was very mild or lacking and light-microscopic evidence of cholestasis was not evident, various ultrastructural changes which had been described in association with cholestasis were detected. The significance of these ultrastructural changes in relevance to cholestasis was difficult to determine, nevertheless electron-microscopic examination could possibly be the most sensitive means for the diagnosis of cholestasis. These ultrastructural changes appeared to be indifferent to the necrotizing process of liver cells in experimental hepatitis B.

Animals↗