The Finding of Pacific Transvenid Acanthocephalan in the Arabian Gulf, with the Description of Paratrajectura longcementglandatus N. Gen., N. Sp. from Perciform Fishes and Emendation of Transvenidae.

The acanthocephalan Paratrajectura longcementglandatus n. gen., n. sp. (Transvenidae) is described from specimens of 2 perciform fish species, Nemipterus japonicus Bloch (Nemipteridae) and Otolithes ruber Bloch and Schneider, collected in the marine territorial waters of Iraq and Iran in the Arabian Gulf. Metal analysis of hook tip, middle, and base is also described using energy disruptive analysis for X-ray. The new genus is distinguished from the closely related genus Trajectura Pichelin and Cribb, 2001 described from wrasses (Labridae) (Perciformes) in the Pacific off Australia and Japan by having a proboscis with apical epidermal cone, long rhadinorhynchid-like tubular cement glands, relatively short and lobulated lemnisci, all proboscis hooks with prominent roots, females with subterminal gonopore and a rounded projection on the antero-dorsal end of the trunk, and males with elongate pre-equatorial testes reaching proboscis receptacle. In Trajectura, the proboscis lacks apical epidermal cone, the cement glands are pyriform or ovoid, the lemnisci are digitiform and considerably longer than the receptacle, the posterior proboscis hooks are rootless, the females have prominent finger-like trunk projection and terminal gonopore, and males with equatorial testes that may not be elongate and may be distant from the receptacle. The importance of cement glands in the diagnosis of genera and families in acanthocephalan taxonomy is stressed. Other features especially the type and arrangement of hooks on the proboscis, but not hook roots, are comparable in the 2 genera. Diagnosis of the family Transvenidae is emended.

Description of a New Quadrigyrid Acanthocephalan from Kashmir, with Notes on Metal Analysis and Histopathology, and a Key to Species of the Subgenus Acanthosentis from the Indian Subcontinent.

Acanthogyrus (Acanthosentis) kashmirensis n. sp. is described from recently collected acanthocephalan specimens in the Jhelum River in northern Kashmir that are conspecific with Neoechinorhynchus kashmirensis Fotedar and Dhar, 1977 originally described in a Ph.D. thesis in 1972 from 4 species of cyprinid fishes: Tor tor Hamilton, Bangana diplostoma (Heckel) (syn. Labeo diplostoma Heckel), Labeo rohita Hamilton, and Ptychobarbus sp. Steindachner. The poor unpublished diagnosis was followed by 1 uninformative abstract in a scientific meeting in 1977. The acanthocephalan was later designated as invalid because of the lack of a formal published description and absence of information on deposited type or voucher specimens. Recent collections of specimens of the same species were made from 2 other cyprinid species of cyprinid fishes, Schizothorax plagiostomus Heckel and Schizothorax labiatus (McClelland) from the Sandran River, a tributary of the Jhelum River, in southern Kashmir. It is now possible to provide a full description of these specimens and reassign them in the subgenus Acanthosentis Verma and Datta, 1929 based on the finding of circles of vestigial spines at the anterior end of the trunk of male and female specimens. These vestigial spines are barely visible and easy to miss with optical microscopy. The new species is also characterized by having (1) a para-receptacle structure in males and females, (2) unique double Saefftigen's pouches, (3) large round single-nucleated cells in the proboscis, and (4) the lemnisci being either equal or distinctly unequal with no intermediate states. A key to the species of Acanthosentis of the Indian subcontinent is provided. Histopathological sections show extensive damage to the host intestine with subsequent blood loss, cell necrosis, and attempted encapsulation. Results of the energy dispersive X-ray analysis (EDAX) study show hollow hooks high in sulfur but with limited calcium ions. Hooks of most acanthocephalans studied with X-ray scans are solid with high calcium and low sulfur ions.

Rhadinorhynchus oligospinosus n. sp. (Acanthocephala, Rhadinorhynchidae) from mackerels in the Pacific Ocean off Peru and related rhadinorhynchids in the Pacific, with notes on metal analysis.

Specimens of a new species of Rhadinorhynchus Lühe, 1911 are described from the chub mackerel Scomber japonicus (Scombridae) and the Chilean Jack mackerel Trachurus murphyi (Carangidae) (possibly a subspecies of Trachurus symmetricus) from the Pacific Ocean off the Peruvian coast at the Port of Chicama, La Libertad. Specimens of Rhadinorhynchus oligospinosus n. sp. are somewhat small having 11-14 rows of alternating proboscis hooks with 20-22 hooks each with posteriormost hooks in a continuous ring. Ventral hooks are robust with prominent roots but dorsal hooks are slender and shorter with discoid roots. Trunk spines are in two zones separated by a non-spiny region. Anterior trunk spines are in 2-3 complete circles but posterior spines are only ventral and lateral, and do not extend posterior to the level of the posterior end of the proboscis receptacle in both sexes. The new species is closest to Rhadinorhynchus seriolae (Yamaguti, 1963) Golvan, 1969 found in Japanese and Australian waters, but not as close to 19 other species found in the same Pacific waters off Australia, Japan, and Vietnam. In R. seriolae, posterior trunk spines extend well past the receptacle in females, among other diagnostic differences. Proboscis hooks of the new species were analyzed for chemical elements using X-ray in conjunction with EDAX (energy-dispersive analysis for X-ray) software; sulfur had a higher concentration at the edge than the middle of cut hooks.

A description of Echinorhynchus baeri Kostylew, 1928 (Acanthocephala: Echinorhynchidae) from Salmo trutta in Turkey, with notes on synonymy, geographical origins, geological history, molecular profile, and X-ray microanalysis.

A population of Echinorhynchus baeri Kostylew, 1928 with 18-24 rows of 8-10 proboscis hooks each and long fusiform eggs measuring 95-110 × 18-22 µm collected from Salmo trutta (Salmonidae) in a branch of the Murat River in Turkey is described and specimens are designated as neotype. Specimens of two similar populations of E. baeri (E. baeri Kostylew, 1928 and E. sevani Dinnik, 1932) were previously described from Salmo ischchan in Lake Sevan, Armenia. Waters of Lake Sevan and the Murat River were previously joined during the Middle Miocene-Pliocene. The two populations from Lake Sevan and ours from Turkey had identical morphology and size eggs. The proboscis armature and eggs, among other features of our Turkish specimens, proved intermediate between E. baeri and E. sevani, thus eliminating the significance of the described differences between these two species and confirming their synonymy with priority to Echinorhynchus baeri (junior synonym: Echinorhynchus sevani Dinnik, 1932). Echinorhynchus baeri is apparently a highly variable species. The two descriptions from Lake Sevan did not include features or illustrations of females, except for references to trunk and egg size but the eggs were illustrated. Complete morphometric comparisons are made and females of the Turkish material are described for the first time. DNA sequencing (mitochondrial cytochrome oxidase subunit I gene; nuclear 18S rRNA gene) results from two available E. baeri individuals were equivocal. New features to the Acanthocephala include the presence of rootless uncalcified apical proboscis hooks studied with X-ray microanalysis.

Lesions associated with mineral deposition in the lymph nodes and lungs of cattle: a case-control study of environmental health hazard.

This report focuses on the state of health of the cattle raised in the district of Taranto - city of Italy rated as environmentally at risk. Representative samples of lungs, bronchial and mediastinal lymph nodes of cattle from district of Taranto's slaughterhouses were collected. After a macroscopic examination, samples with marked lesions were processed for light microscopy. Samples were also observed with polarized light microscopy, scanning electron microscopy and with microanalysis. The macroscopic examination revealed that 60 out of 183 samples showed marked lesions. Lung alterations were characterized by thickening of the alveolar septa and by the latter's modifying action on the alveolar spaces, foci of fibrosis and bronchopulmonary inflammation. For 51 out of the 60 samples observed, the histological examination confirmed the presence of pneumoconiosis and lymph nodal anthracosis. Energy-dispersive X-ray microanalysis of lung samples identified a wide range of elements including silicon, aluminium, titanium, iron, carbon and small amount of the other metals. In the lymph-nodes the same kind of metals with a different levels of distribution was observed. Our survey on cattle farmed in areas at high risk of pollution may be helpful to the estimation of the exposure risk for man to environmental contaminants and to the evaluation of the occurrence of the pathological manifestations as well.

Hepatocyte nuclear structure and subcellular distribution of copper in zebrafish Brachydanio rerio and roach Rutilus rutilus (Teleostei, Cyprinidae) exposed to copper sulphate.

Copper is a trace element essential to life, but also a heavy metal with toxic effect clearly demonstrated. Cu induced perturbations in fish liver are well documented but the variability of the reported results is large. In this study two cyprinids, zebrafish and roach, were exposed to copper. Reported histocytological changes are either adaptative or degenerative depending on fish species, concentration of metal, and duration of exposure. Hepatic subcellular distribution of copper was determined by X-ray microanalysis in control and Cu-exposed roach and zebrafish. Sublethal copper sulphate contamination induced the development of a particular nucleolar alteration forming a network or honeycomb like structure in liver. This perturbation is observable in almost all the hepatocytes of zebrafish and roach exposed to copper for a minimum of 4 days of exposure. It seemed to concern more precisely the pars fibrosa. X-ray microanalysis showed that the appearance of network nucleolus was in relation to a Cu accumulation. Cu deposit was well located in the network as pars granulosa and nucloplasm showed very lower metal concentrations. The origin and consequence of network structure in nucleolus was discussed.

Tissue distribution and subcellular localization of trace metals in the pond snail Lymnaea stagnalis with special reference to the role of lysosomal granules in metal sequestration.

The present study was undertaken to elucidate the cellular mechanisms, which govern metal sequestration and detoxification in gastropods. For this purpose the pond snail, Lymnaea stagnalis was exposed to environmentally relevant concentrations of three species of metals (Al, Zn and Cd) for 30 days and the localization and fate of these metals were followed in different tissues of the snails. The measurement of relative distribution of metals between tissues revealed that the digestive gland and kidney account for most of the accumulated metals. Al and Cd (non-essential metals) were redistributed to the digestive gland, possibly because of the presence of specific binding entities in the digestive glands of the herein species. This study focuses on the role of intracellular metal-containing granules on metal sequestration. Three main types of granules were identified in the digestive gland cells namely small, green and yellow granules. The morphological examination and the progressive accumulation of elements within these granules revealed that they are developmental stages with the yellow granule being the mature one. The total number of these granules was found to be significantly increased upon exposure of the snails to Al only. This increase may be a response to the large amount of Al that is accumulated through feeding route of this grazing snail. X-ray microanalysis (XRMA) revealed that metals were localized in all three types of digestive gland granules. The increased amount of ligands (P and S) in the granules may give evidence for their role in metal sequestration. Levels of Al and P were positively correlated in the digestive gland granules. It is possible that aluminium is bound to phosphorus to render it insoluble and so to both immobilize it within the lysosome and to be excreted in a highly insoluble form. On the other hand, both Zn and Cd induced marked upregulation of S in mature (yellow) granules by 26- and 11-folds, respectively. The lysosomal codeposition of S and either Cd or Zn in the lysosomal granules in addition to the increase in RER cisternae may indicate that the exposure to these metals could induce metallothionein synthesis in the cells. The microscopical examinations in the present study revealed that metal detoxification from the digestive gland cells may occur via faeces or via basal exocytosis towards hemocytes dispersed by the connective tissue in the visceral mass. In the kidney, one type of granules, the excretory concretions, was identified in the nephrocytes. The significant increase in the number of these concretions in the snail L. stagnalis upon exposure to metals may give further evidence for their role in metal excretion.

Morphological and histochemical observations of the organic components of ostrich eggshell.

The organic component of the avian eggshell can be divided into 3 portions, the shell membranes, the matrix and the cuticle. These have been well characterised in the chicken but little has been published with regard to the ostrich (Struthio camelus). A number of recent studies have indicated that the cause of intra-shell embryonic deaths in the ostrich is similar to intra-shell embryonic deaths that occur in the chicken. These deaths in the chicken are associated with the loss of or damage to the waxy cuticle and other organic components of the eggshell, which is reported to be absent in the ostrich eggshell. In this study, preliminary morphological and histochemical analyses, at the level of the light and electron microscope, have characterised the various organic components of the ostrich eggshell. The results of the histochemical and electron microscopical analyses suggest that there may only be 1 shell membrane in this species, which could play a major role in the limitation of bacterial penetration to the embryonic chamber The shell membrane has a distinct elemental profile as determined by EDS analysis. The matrix is shown to decrease in mesh size from the mammillary layer to the vertical crystal layer. The closer packing of the mesh may indicate the presence of a morphologically discernible termination signal to calcification or the remnants of an evolutionary calcified cuticle. The matrix of the pores may also form a defensive barrier against bacterial invasion, which could be damaged as a result of dipping the eggs before incubation.

Petrographic and geochemic evaluation of equine enteroliths.

OBJECTIVE: To characterize the texture, mineralogic features, and chemical features of enteroliths obtained from horses. SAMPLE POPULATION: Enteroliths from 13 horses with colic. PROCEDURE: Enteroliths were harvested from 13 horses that underwent ventral midline celiotomy for treatment of colic or necropsy because of colonic obstruction and rupture caused by enteroliths. Dietary and environmental history were determined via questionnaires or evaluation of medical records. In 7 horses that underwent surgical treatment for enterolithiasis, samples of colonic contents were obtained via an enterotomy in the pelvic flexure. Colonic concentrations of magnesium (Mg), phosphorus (P), sulfur (S), sodium (Na), calcium (Ca), and potassium (K) were determined. Enteroliths were analyzed via electron microprobe analysis and X-ray diffraction. RESULTS: Enteroliths varied widely regarding degree of porosity, presence and distribution of radiating texture, and composition and size of the central nidus. A distinct concentric banding was identifiable in all enteroliths. Struvite was the predominant component of all enteroliths, although Mg vivianite was identified in 5 enteroliths, and there were variable quantities of Na, S, K, and Ca in the struvite within enteroliths. Despite an abundance of Ca in colonic fluids, Mg-phosphate minerals were preferentially formed, compared with Ca-phosphates (apatite), in equine enteroliths. CONCLUSIONS AND CLINICAL RELEVANCE: Enteroliths comprise 2 major Mg phosphates: struvite and Mg vivianite. There is wide variability in macrotexture and ionic concentrations between and within enteroliths.

Ultrastructure of selected calcium oxalate-containing urinary calculi from dogs.

OBJECTIVE: To elucidate the ultrastructural details of calcium oxalate-containing urinary calculi from dogs. Sample Population-38 specimens selected from a collection of 8,297 oxalate-containing urinary calculi from dogs: 22 specimens composed of calcium oxalate (calcium oxalate monohydrate [COM], calcium oxalate dihydrate [COD], or COM and COD) and 16 specimens composed of calcium oxalate with amorphous calcium phosphate. PROCEDURE: Analyses of specimens included use of plain, reflected, and polarized light microscopy, X-ray diffractometry, scanning electron microscopy (SEM) with backscattered electron (BSE) imagery, and electron microprobe analysis. RESULTS: Four texture types were observed in calcium oxalate calculi; 4 texture types of calcium oxalate-calcium phosphate-mixed calculi were recognized. Texture types were delineated through differences in calcium oxalate crystal sizes, which were affected by urine supersaturation and abundance of crystal nucleation sites. Segregation of calcium oxalate from calcium phosphate indicated they do not precipitate under the same conditions. Deposition of calcium phosphate between calcium oxalate crystals decreased the volume of pore spaces within calculi. Porosity was observed along boundaries between COM and COD. Minute pores increased the surface area of calculi exposed to urine, and this increase in liquid-solid interface promotes interaction of crystals with the surrounding urine. CONCLUSIONS AND CLINICAL RELEVANCE: Calcium oxalate urolithiasis is of major concern, because it is often a recurrent disease among dogs, principally treated by surgical removal of calculi, with few effective dissolution strategies. Understanding the ultrastructure and mineralogic content of calcium oxalate and its association with amorphous calcium phosphate is a step toward the solution of this increasingly important medical problem.

Silicate pneumoconiosis in hens.

Thirteen cases of silicate pneumoconiosis in 3- to 4-year-old hens are described. Ten of the birds were raised in the suburbs of a city near several chalk quarries and two cement-works; the remaining three hens (aged 3 years) had lived in an environment with high particulate pollution from a nearby brick-works in which large amounts of clay were used daily. Silicotic granulomas composed of dust-laden macrophages were scattered over the lungs. They were located mainly in the infundibula and atria of tertiary bronchi and around vessels; more rarely they occurred in the lamina propria mucosae of primary and secondary bronchi. Energy dispersive x-ray microanalysis coupled with both transmission and scanning electron microscopy revealed that the dust was composed mainly of silicon, aluminium, calcium, iron and potassium. Titanium, sulphur, magnesium, zinc, copper and chlorine were also found. It is concluded that animals raised in polluted environmental conditions may serve as an important indicator of risks to human health and pathogenetic mechanisms. Thirteen cases of silicate pneumoconiosis in 3- to 4-year-old hens are described. Ten of the birds were raised in the suburbs of a city near several chalk quarries and two cement-works; the remaining three hens (aged 3 years) had lived in an environment with high particulate pollution from a nearby brick-works in which large amounts of clay were used daily. Silicotic granulomas composed of dust-laden macrophages were scattered over the lungs. They were located mainly in the infundibula and atria of tertiary bronchi and around vessels; more rarely they occurred in the lamina propria mucosae of primary and secondary bronchi. Energy dispersive x-ray microanalysis coupled with both transmission and scanning electron microscopy revealed that the dust was composed mainly of silicon, aluminium, calcium, iron and potassium. Titanium, sulphur, magnesium, zinc, copper and chlorine were also found. It is concluded that animals raised in polluted environmental conditions may serve as an important indicator of risks to human health and pathogenetic mechanisms.

Calcium oxalate crystalluria in a goat.

As part of a routine health evaluation of an 8-month-old female Nubian goat, serum biochemical analyses and urinalysis were performed. Most serum biochemical values including concentrations of blood calcium and indicators of urinary system dysfunction, such as blood urea nitrogen, creatinine, and phosphorous concentrations, were within reference ranges. An aliquot of voided urine was hypersthenuric and acidic and contained numerous typical cuboidal-bipyramidal calcium oxalate dihydrate crystals and unique rectangular parallelepiped crystals that were confirmed by energy dispersive X-ray microanalysis as being of calcium oxalate dihydrate composition. We hypothesize that the calcium oxalate crystals resulted from a diet containing calcium and oxalic acid. Treatment was not administered, and the goat remained healthy during the ensuing year.

Lyssaviral infection and lead poisoning in black flying foxes from Queensland.

Pteropid lyssaviral infection, lead poisoning, and the difficulties in diagnosing pteropid lyssaviral infection using histopathological examination of tissues are described in wild black flying foxes (Pteropus alecto) from northern Queensland (Australia). An adult female P. alecto showed aggression before death in January 1995. Lead poisoning was diagnosed due to the presence of intranuclear lead inclusion bodies in renal proximal convoluted tubular epithelium and high concentrations of lead in renal and hepatic tissues, 370.03 +/- 7.35 ppm and 16.76 +/- 0.53 ppm, respectively. Renal inclusion bodies were composed of lead, calcium, phosphorus, and possibly sulphur; some inclusions had their granules arranged in concentric bands. This bat also had a moderate concentration (8.09 +/- 0.18 ppm) of cadmium in renal tissue. An adult male P. alecto presented with ascending paralysis before it died in May 1996. Pteropid lyssaviral infection was diagnosed subsequently in both bats in September 1996 by immunofluorescent and immunoperoxidase antibody tests for rabies on brains and viral culture from brains. Neither bat had gross or microscopic lesions of the brain that suggested a lyssaviral infection, apart from occasional, subtle, eosinophilic cytoplasmic inclusions in the neurones of the brain stem of the female. These cases illustrate the need for a specific test to detect pteropid lyssavirus such as an immunofluorescent antibody test for lyssavirus rather than histopathological examination of tissues.

Pulmonary histiocytosis in tree shrews (Tupaia belangeri).

Granulomatous lesions similar to those of pulmonary histiocytosis in rats developed spontaneously in the lungs of captive tree shrews. Incidence peaked in 3-year-old tree shrews. Sex dependency was not observed, and development of the granulomas was unrelated to experimental procedures because the lesions were observed in animals from the breeding stock as well. The granulomas consisted of amorphous material, foam cells, and a few foreign body-type multinuclear giant cells; they also contained acicular clefts, often with some fibrous material. Alveolar septa within and adjacent to the granulomas were thickened in most instances, but did not contain inflammatory cells in appreciable numbers or amyloid. Only traces of cholesterol and calcium were detected in the amorphous material; neutral fat was stored in the foam cells and the amorphous masses. Fibers without birefringency were documented by polarization and scanning electron microscopy in the vicinity of granulomas, which in energy-dispersive X-ray microanalysis consisted mostly of calcium, but lacked silicon.

Elemental composition of muscle at rest and potassium levels in muscle, plasma and sweat of horses exercising at 20 degrees C and 35 degrees C.

In this study, 4 Standardbred geldings were exercised at 20 and 35 degrees C. The exercise test (ET) consisted of 2 exercise bouts separated by 2 h of rest in their boxes. Blood samples were taken before, during and after the second exercise bout and muscle (m. gluteus medius) biopsies were taken before the first exercise bout and after an intensive trot over 2600 m in the second exercise bout. The blood samples were analysed for plasma potassium and total plasma protein concentration (TPP) and the muscle fibres were analysed for elemental composition by x-ray microanalysis. The intracellular content was as follows: sodium (Na) = 40 +/- 7; magnesium (Mg) = 32 +/- 4; phosphorus (P) = 282 +/- 15; sulphur (S) = 222 +/- 13; chloride (Cl) = 119 +/- 31; potassium (K) = 304 +/- 21 and calcium (Ca) = 8 +/- 2 mmol/kg dry weight under resting conditions. Intracellular potassium content increased after exercise compared to resting values. There was a good correlation between exercise intensity, plasma potassium concentration and shifts in plasma volume, indicated by alterations in TPP. This probably reflects the very fast shift of potassium and fluid between muscle and plasma. Plasma potassium concentrations decreased below resting values post exercise. The higher dehydration degree and potassium sweat loss after exercise at 35 degrees C was not reflected in lower muscular potassium content, but by a lower plasma potassium/total plasma protein ratio after exercise, indicating less circulating potassium.

Lesions associated with mineral deposition in the lymph node and lung of the dog.

This report includes details of the clinical and pathologic features of 31 dogs with a range of systemic illness and granulomatous lymphadenopathy associated with the presence of birefringent crystalline material within lymph nodes. Similar crystalline material was found in the lymph nodes of dogs with lymphoma (n = 9) and as an incidental finding within the canine lung (n = 9). The mineral content of these crystals was determined by electron microprobe analysis and interpreted in light of the composition of known geological or human-made compounds. A wide range of elements was identified including silicon, sulfur, copper, calcium, and aluminium, with lesser proportions of phosphorus, sodium, potassium, iron, magnesium, titanium, nickel, and chromium. Many of these compounds may have originated from exogenous natural and human-made sources, but some compounds (notably phosphates and sulfates) are uncommon or not found in nature and may have been formed within the tissues of the body (biomineralization). The inflammatory response induced by the presence of these minerals within lymphoid tissue may trigger altered immunoregulation, accounting for the spectrum of disease observed.

Extrapulmonary silicosis in two water buffaloes.

Two cases of extrathoracic silicosis in buffaloes raised near a quartz quarry and suffering from clinically severe silicosis are described. The extrapulmonary changes were characterized by silicoconiotic nodules in the tonsils, mesenteric lymph nodes and spleen. A combination of energy dispersive X-ray microanalysis and scanning electron microscopy revealed that the mineral component of these lesions consisted mainly of silicon, aluminium, iron, calcium, magnesium, zinc, sulphur and potassium. It is concluded that domestic animals raised in polluted environmental conditions represent an important biological source from which helpful data may be obtained for assessing risks to human health and gaining new insight into pathogenetic mechanisms.

Ultrastructure and mineral composition of urinary calculi from horses.

Urinary calculi from 17 horses with urolithiasis were examined to study their mineral content and ultrastructure. Among the analytic methods used were X-ray diffractometry, scanning electron microscopy, and electron microprobe analysis. The calculi initially were observed by use of a stereoscopic dissecting microscope and generally were found to have nodular surfaces surrounding a banded or granular-to-chalky interior. Observation by scanning electron microscopy revealed an intricate pattern of irregularly concentric, fine bands and spherules. These had a round, finely banded, globular texture formed by precipitation of ultrafine-grained radiating crystals. The original pore spaces (ie, between spherules, between bands and spherules, or between crystal generations) could be observed as primary porosity. Precipitation and dissolution of these urinary calculi were observed to be spontaneous processes, which can occur simultaneously within an individual calculus. Another prominent feature of the ultrastructure was secondary porosity (spontaneous dissolution) which, in its incipient stages, appeared to be site-selective (ie, some bands appeared to be more susceptible to development of pinpoint porosity). Textures indicative of dissolution were observed not only on the calculus surface, but within the calculus interior as well. Areas that had more advanced stages of dissolution, resulting in increased secondary porosity, also were observed. All 17 samples of the study were found to be composed of calcium carbonate in the form of the mineral calcite, although minor quantities of 2 other polymorphs of calcium carbonate, minerals vaterite and aragonite, also were encountered. Vaterite was observed in 5 of the samples, whereas aragonite was found in 1 sample. Strontium and sulfur were observed as trace elements in 3 of the calculi, whereas magnesium was present in all calculi. Magnesium was observed to substitute for calcium within the calcite crystal lattice in larger quantities than those of strontium or sulfur. Magnesium K alpha X-ray dot maps generated by use of an electron microprobe analyzer indicated that the distribution pattern of magnesium appeared to closely follow layer-by-layer growth of the calculus. Magnesium distribution also appeared to be related to porosity development. In samples where preferential dissolution was observed, the more porous areas had higher magnesium content. Quantitative chemical analyses, using the electron microprobe analyzer, confirmed these observations. Association of the magnesium distribution pattern to the primary growth texture of the calculus indicated that magnesium content of the calculus varied during the formation process. This also indicated that changes in urine chemical analytes may be reflected in composition of the calculi formed.(ABSTRACT TRUNCATED AT 400 WORDS)

Silicate pneumoconiosis in pigs: optical and scanning electron microscopical investigations with X-ray microanalysis.

Four cases of silicate pneumoconiosis are described in pigs raised near several chalk quarries and two cement works. The pulmonary changes were characterized by thickened alveolar septa, resulting in distorted airspaces, and small foci of initial fibrosis. In the bronchiolar and alveolar sites, as in the interstitium, free and intracytoplasmic dust was detected. An energy dispersive X-ray microanalysis coupled with a scanning electron microscope revealed that this dust was composed mainly of silicon, calcium, potassium, sulphur, aluminium and iron. In lung-associated lymph nodes, severe lymphoid cell depletion and dilatation of peritrabecular and subcapsular sinuses were constant findings. The inorganic material found in the lymph nodes contained the elements listed above. Air samples from the same geographical area revealed particulate pollutants, the qualitative features of which were similar to those found in lung and lymph nodal tissue. It is concluded that domestic animals raised in polluted environmental conditions represent an important biological source from which helpful data may be obtained for assessing risks to human health.

Spontaneous globoid mineralization in the cerebellum of rats.

Cerebellar globoid mineralization in two rats was examined by light and electron microscopy, and by X-ray microanalysis. The mineralization was round to oval in shape; it varied in size and was positive for the periodic acid-Schiff and von Kossa reactions. Ultrastructurally, a concentric lamellar structure was prominent in moderately electron-dense depositions. Elemental analysis revealed the presence of large amounts of calcium and phosphorus, and small amounts of zinc, potassium and aluminum.