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Biomedical subjects

P Ingram

Publications and source records attributed to P Ingram.

At least 55 records · Page 3Linked to original sources
PubMed1983

Three-dimensional configuration of the mitochondria in cultured heart cells.

The mitochondria of chick heart cells grown in monolayer culture occupy a relatively large percentage (30%) of the cell cytoplasmic volume, as determined by thin section morphometry, and vary in their ultrastructural configuration in response to different functional states of the cell. The present study was undertaken to determine the three-dimensional structure of the mitochondria in cardiac cells, since reconstruction experiments have demonstrated the existence of a mitochondrial network in cardiac and other tissues, e.g. diaphragm, soleus and vastus muscle, kidney and urinary bladder, in vivo. Confluent monolayers of synchronously beating embryonic chick heart cells were fixed, stained with a mitochondria-specific heavy metal complex (Pb-Cu citrate), and processed for either transmission electron microscopy (TEM) or scanning electron microscopy (SEM) and backscatter electron imaging (BSI). Both secondary and backscatter images revealed the presence of many thin, extremely elongate structures which in stereo views appeared as branching, anastomosing networks. TEM demonstrated localization of the electron dense stain to either nuclear or mitochondrial membranes, structures which were easily distinguished with SEM or BSI alone. These morphological results indicate that many mitochondria of the cultured heart muscle cell are interconnected and suggest that this morphological network may represent a parallel functional unit which maintains the energy state of the cell.

Animals↗
PubMed1983

Cutaneous pigmentation secondary to amiodarone therapy.

Amiodarone (Cordarone) is an iodinated cardiac antiarrhythmic drug that causes a slate-gray discoloration of the sun-exposed skin and a yellow-brown stippling of the cornea. Histopathologically, biopsy specimens of aminodarone pigmentation sites disclose yellow-brown refractile granules in the reticular dermis. These granules were characterized by transmission electron microscopy as being concentrically arranged intralysosomal inclusions ("myelinlike" bodies) in dermal endothelial cells and perivascular smooth-muscle cells. Electron probe x-ray analysis of these same inclusions disclosed definite peaks for iodine, evidence for the presence of amiodarone or a metabolite of the drug at these sites. Amiodarone, then, concentrates in lysosomes and causes an accumulation of lipids similar to what has been seen with other cationic amphiphilic compounds, such as the glycosphingolipid stored in Fabry's disease. Amiodarone must be recognized as a cause of a drug-induced lipid storage disease with cutaneous and corneal manifestations.

Adult↗
PubMed1983

Acute toxicity of lead particulates on pulmonary alveolar macrophages. Ultrastructural and microanalytical studies.

Although it is well established that respiratory uptake of lead-containing particles plays a substantial role in the epidemiology of plumbism, relatively little is known about the role of the pulmonary alveolar macrophage in lead poisoning. An in vitro system was designed to investigate the effects of lead oxide particles of respirable size on the rabbit alveolar macrophage. The studies were concerned with the intracellular solubility of PbO and Pb3O4 and changes in fine structure attributable to lead toxicity. The distribution of phagocytosed lead and its intracellular reprecipitation complexes was established by electron microprobe analysis and secondary ion mass spectroscopy in conjunction with transmission electron microscopy, scanning electron microscopy, scanning transmission electron microscopy, and backscatter imaging. It was found that Pb3O4, PbO and PbO-coated particles were ingested by the rabbit alveolar macrophages and that each of these lead oxide compounds produced similar damage to the fine structure of the cell. Swelling of the mitochondria, nuclear membrane, and endoplasmic reticulum was common, as well as were characteristic reprecipitation complexes of lead, phosphorous, and calcium within the nuclear heterochromatin and cytoplasm of the cell. The precipitation complexes were not seen in cells incubated with the particles if phagocytosis was blocked by 0.22-microns, membrane filters. It was concluded that phagocytosis of these lead oxide particles was necessary to produce the cytopathic changes. It is suggested that solubilization of lead from the ingested particles in phagosomes of macrophages results in the liberation of intracellular lead with the resultant formation of reprecipitation complexes.

Animals↗
PubMed1982

Ion beam etching effects in biological microanalysis.

Oxygen ion beam sputter etching used in SIMS has been shown to produce morphologic effects which have similarities and differences in comparison to rf plasma etching of biological specimens. For example, selective retention of nuclear and plasma membranes is observed in both cases, however, heterochromatin is preferentially sputtered by O2+ bombardment in SIMS and preferentially preserved during O2 plasma etching. Sputter yield variations resulting from structural microheterogeneity are illustrated (e.g. etch-resistant nucleoli in preferentially etched nuclei), including their impact upon ion image formation in an ion microanalyzer. These image artifacts must be evaluated before secondary ion images revealing subcellular organelles can be related quantitatively to elemental localization in cells or tissues. To minimize gross surface roughness effects such as cone formation induced by ion bombardment, ion imaging studies of thin sections using low primary ion doses are indicated.

Animals↗
PubMed1981

Infantile pulmonary hypertension associated with foreign body vasculitis.

An infant dying with pulmonary hypertension had a pulmonary vessel foreign body vasculitis as identified by light microscopy and characterized ultrastructurally by scanning electron microscopy and energy-dispersive x-ray analysis. The inclusions were of two distinct types: those containing silicon and titanium, and others consisting of talc. The possible sources of these inclusions and the importance of considering foreign body vasculitis in the pathogenesis of clinically idiopathic pulmonary hypertension are discussed.

Humans↗
PubMed1981

Crystalline deposits of calcium and phosphorus: their appearance in glomerular basement membranes in a patient with renal failure.

The kidneys and lungs of a 71-year-old man with a 30-month history of biopsy-proven Wegener's granulomatosis were examined at autopsy. They displayed striking crystalline deposits in glomerular basement membrane (GBM) and, to a much lesser extent, other basement membranes. The patient had been in renal failure, with peritoneal dialysis instituted three weeks before death. Energy-dispersive x-ray microanalysis of these deposits showed them to consist of calcium and phosphorus. Transmission electron microscopy revealed their presence diffusely throughout all layers of GBMs, with focal areas showing early reactive membrane formation. Control studies confirmed these deposits as being an endogenous, in vivo phenomenon, representing a morphologic finding not previously described to our knowledge.

Acute Kidney Injury↗
PubMed1980

Energy dispersive x-ray detection of thorium dioxide.

Since the recognition of the development of certain malignant neoplasms in association with thorium dioxide (Thorotrast), its presence has been documented by light microscopic appearance and time-consuming autoradiography. Energy dispersive x-ray microanalysis can be used in the rapid documentation of thorium in paraffin-embedded tissues and it is confirmed that thorium is the principal component of the granular deposits described by light microscopy.

Bone Marrow↗
PubMed1980

Ion microanalysis of cells.

The application of ion microanalysis (IMA) to the chemical characterization of freeze-fixed, freeze-dried cells is reviewed. Particular emphasis is given to pathological studies involving the determination of the chemical composition of isolated cells (e.g. rabbit alveolar macrophages--RAMs) exposed in vitro to toxic species (e.g. Pb3O4 particles). Ion microscopic results indicated that lead from Pb3O4 migrated into the RAMs and subsequently formed phosphorous-containing compounds. Quantitative comparisons of the relative concentrations of physiologic elements in Pb3O4-treated versus control RAMs also were made using ion microanalytical techniques. The Pb3O4 results illustrate that the three-dimensional analysis capabilities of the IMA may be exploited for the in situ observation of the penetration of xenobiotic agents into cell interiors and their subsequent intracellular chemistry. The potential advantages of ion microanalysis for the characterization of cells include high elemental sensitivity (including low atomic number elements and diffusible ions), broad elemental coverage, three dimensional analysis, and isotopic information. The major limitations include non-idealities of the ion sputtering process, the constraints on the lateral resolution available to identify subcellular features, and the difficulties inherent in the determination of absolute elemental concentrations.

Animals↗
PubMed1980

Total rate imaging with x-rays (TRIX)--a simple method of forming a non-projection x-ray image in the SEM using an energy dispersive detector and its application to biological specimens.

X-ray images can be formed in a conventional scanning electron microscope equipped with a Si(Li) energy dispersive spectrometer. All the x-ray events generated in the electron beam scanning process are synchronously displayed in the same manner as for dot maps. The quasi-digital image formed using Total Rate Imaging with X-rays (TRIX) exhibits good gray scale contrast and is dependent on topography, orientation and atomic number. Although this latter dependence is complex, it has been found useful in locating several types of inclusions in lung tissue (silicosis), human alveolar macrophages and cigarette smoke condensate. This is because of the greater depth of penetration of x-rays than backscattered electrons (BSE) usually used for such localizations in a matrix, and the negligible sensitivity of the Si(Li) detector to x-rays from an organic biological matrix. The optimum procedure is to use a combination of TRIX and BSE to investigate such specimens.

Electron Probe Microanalysis↗
PubMed1979

Preparative techniques for freezing and freeze-sectioning macrophages for energy dispersive x-ray microanalysis.

In order to study the subcellular distribution of normal intracellular electrolytes and of metal pollutants, rabbit alveolar macrophages and mouse peritoneal macrophages were maintained in standard tissue culture medium with or without various concentrations of cadmium chloride or ammonium vanadate. A variety of preparative techniques were employed to study both monolayers and cell pellets by light microscopy, transmission electron microscopy, scanning electron microscopy and energy-dispersive x-ray microanalysis. Pellets of macrophages centrifuged in narrow bore centrifuge tubes were successfully snap-frozen in liquid-nitrogen-cooled liquid propane and either sectioned on a cryoultramicrotome or freeze-substituted with 1% osmium tetroxide in acetone and embedded in Epon. Spot probes of freeze-dried, frozen thin sections for normal intracellular electrolytes such as potassium, phosphorus and sulfur showed good localization to the cells and differences between organelles. Monolayers were freeze-dried and directly embedded in Epon. When Epon thin sections of these cells and of the freeze-substituted, Epon embedded pellets were obtained with a dry knife, intracellular electrolytes such as potassium, phosphorus and cadmium could still be detected by energy-dispersive x-ray microanalysis. It is concluded that in studies using snap-freezing for element localization, maximum information is obtained with the simultaneous application of a combination of preparatory techniques.

Animals↗
PubMed1979

Ultrastructure and x-ray microanalysis of macrophages exposed to cadmium chloride.

Macrophages have a direct role in the inflammatory response to cadmium exposure. Cadmium is not only an important air pollutant, but is also one component of cigarette smoke. To study the effects of soluble cadmium on macrophages, two model systems were chosen:rabbit alveolar macrophages (RAMs) obtained by pulmonary lavage and peritoneal macrophages elicited by intraperitoneal injections of 10(7) viable M. bovis, bacillus Calmette Guérin (BCG MACs). Macrophages were maintained in standard tissue culture medium from 4 to 30 hours with concentrations of cadmium chloride (CdCl2) ranging from 0 to 1.0 mM. Attached macrophages and RAMs in suspension were studied by conventional transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy dispersive x-ray microanalysis (EDX). In addition to routine techniques for TEM and SEM, preparatory procedures included snap freezing in liquid propane, and either cryoultramicrotomy or freeze-substitution with 1% osmium tetroxide in acetone. By TEM many macrophages exhibited laminated nuclear inclusions at doses as low as 0.05 mM CdCl2) (at 20 hrs) and as early as 4 hrs (at 1.0 mM CdCl2). Sections of cells fixed by freezing exhibited the same nuclear inclusions as well as mitochondrial densities that were not visible with any other preparative technique. Cadmium was demonstrated in the nuclear inclusions and mitochondrial densities by EDX in snap frozen cells. Lesser amounts of cadmium were also detected diffusely in treated cell cytoplasm and nuclei. Cadmium was only detected by EDX in cells fixed by freezing. These studies document the localization of Cd in nuclear inclusions and mitochondria providing morphological support for the biochemical findings of other laboratories. In addition, the value of fixation by freezing over conventional chemical fixation is illustrated.

Animals↗
PubMed1977

Scanning and transmission electron microscopy of human prostatic acinar cells.

Benign hyperplastic and neoplastic human prostate tissue samples were obtained by needle biopsy, transurethral resection or open prostatectomy. Acinar cells of both types of tissues were examined in the scanning electron microscope. It had been reported previously that adenocarcinoma acinar cells were more heterogeneous in size and shape than BPH acinar cells; the purpose of this study was to determine if there were surface morphology differences between the two types of tissues. Acinar cells were found to be extremely heterogeneous in their surface morphologies; three major types of surface morphologies were present - microvillous, ruffled, and bare. Within each class of surface morphology there was heterogeneity, both in size and density, of surface structures present. Microvillous, ruffled, and bare cells appeared to be present in normal, BPH, and neoplastic acini with no significant qualitative or quantitative differences in surface morphologies. Infrequently, it was possible to distinguish between well-differentiated and poorly-differentiated carcinomas because cells of the latter tissues were present in sheets rather than acini and appeared flat and totally devoid of surface detail. The SEM studies also sought to determine a marker to establish the origin of prostate tissue culture cells as normal, BPH or cancerous. Surface morphologies from tissues could be traced into the tissue cultures; again, three types of cells are present - bare, microvillous, and ruffled. However, since surface morphology does not appear to be a distinguishin feature of the pathology of the tissue it cannot provide a distinguishing marker for the origin of tissue culture cells. Scanning electron microscopy also provided an opportunity to observe possible secretory mechanisms and products in the prostate acinar cells.

Adenocarcinoma↗
PubMed1977

Investigations of black bronchoalveolar human lavage fluid.

The removal by bronchoalveolar lavage (two occasions) of 10(11) black macrophages containing crystals of aluminum silicate, large amounts of amorphous carbon, and oxidized lipids was followed by considerable improvement in gas exchange in a patient. Sixty-eight percent of these pulmonary macrophages were viable and normal, as judged by chemotatctic and phagocytic activity. Except for cigarettes, no source for the previously mentioned ingested foreign substances was found. These observations suggest that removal by lavage of nonviable macrophages laden with foreign bodies from distal portions of the lungs of pulmonary patients may be therapeutically useful.

Carbon↗
PubMed1977

Calcification of soft contact lenses in patient with dry eye and elevated calcium concentration in tears.

Following radiotherapy for an extensive intraepithelial carcinoma of the conjunctiva and eyelid, a patient developed opacification of soft contact lenses used on the same side. Calcilm was demonstrated within the contact lenses by cytochemical methods and by energy-dispersive x-ray microanalysis. The phenomenon was associated with unilateral tear insufficiency and an elevated tear calcium level as determined by atomic absorption spectrophotometry.

Calcium↗