Calcium Concretions Research Articles

Images- Pulmonary Alveolar Microlithiasis (PAM)

Pulmonary alveolar microlithiasis (PAM) is a rare disease of unknown origin in which calcific concretions collect in alveolar spaces. No known cause for the disease had been identified and there appears to be no systemic disorder of calcium metabolism. Plain chest X-ray shows a white lung consisting of fine sandlike micro calcification diffusely scattered throughout both lungs with high density at lung basis. CT reveals ground glass haze with inter and intra lobular septal thickening suggestive of crazy paving pattern. We here report the typical X-ray and HRCT images of a case of PAM: a rare disease characterized by wide spread sand like intra alveolar calcifications.

Malacoplakia of the tongue complicating the site of irradiation for squamous cell carcinoma with review of the literature

Malacoplakia is a benign and uncommon inflammatory response that develops most frequently in the genitourinary tract but has been reported at other sites. We report the case of 67-year-old man who presented with a lesion at the base of the tongue 7 months after chemoradiation for biopsy-proven invasive squamous cell carcinoma of the tongue. The lesion showed intense avidity by positron emission tomography and was biopsied with the putative clinical diagnosis of recurrent malignancy. Histologically, the lesion showed the characteristics of malacoplakia as well as abundant intracellular gram-negative bacilli. Ultrastructural analysis revealed giant lysosomes, intracytoplasmic calcific concretions (Michaelis-Gutman bodies), and partially digested gram-negative bacilli within vacuolated lysosomes of macrophages. To our knowledge, this is the seventh reported case of malacoplakia of the tongue and the first to develop at the site of prior radiation treatment of a carcinoma. The clinical features of this case, a review of previously reported cases, and a consideration of pathogenesis are presented.

13. Psammoma bodies on screening cervical smear associated with underlying ovarian serous borderline tumour: a case report

Psammoma bodies are microscopic, extracellular, calcific concretions. They are most commonly seen in, but not limited to, papillary serous carcinoma of ovary, papillary thyroid carcinoma and meningioma. The presence of psammoma bodies in cervical smears is a rare finding which may be associated with a range of benign and malignant gynaecologic conditions or with no identifiable cause at all. Reported is a case of an asymptomatic, 55-year-old postmenopau-sal woman whose routine screening cervical smear contained numerous psammoma bodies, some of which were associated with atypical glandular cells. Subsequent follow-up led to the diagnosis of serous borderline tumour involving the surface of both ovaries in conjunction with right ovarian serous cystadenofibroma. This case, along with reviewed current literature, highlights the importance of identification of psammoma bodies in cervical smears and further, supports the instigation of gynaecological follow-up to exclude sinister underlying pathology.

Cytological diagnosis of peritoneal endometriosis

Sir, Endometriosis is a common disease characterized by ectopic growth of endometrial tissue that responds to hormonal stimulation. It primarily affects women in the reproductive age group with mixed symptomatology. Cytological features of endometrial cells in peritoneal fluid are not well described, which we wish to highlight. A 30-year-old woman presented with lower abdominal pain and dysmenorrhoea of 1 year duration. On examination, she had mild ascites. Bilateral cysts were seen near the fallopian tube on laparoscopy. Diagnostic considerations included neoplastic process or pelvic endometriosis. A peritoneal wash was performed and 100 mL of haemorrhagic fluid was sent for cytological examination. On microscopy, the fluid showed the presence of endometrial cells. The glandular epithelial cells were arranged in variably sized spheres in which the periphery showed epithelial cells, along the border and as a honeycombed sheet, with a cluster of stromal cells in the centre having hyperchromatic nuclei, scant cytoplasm and indistinct cytoplasmic borders [Figure 1]. There was no nuclear atypia and the nucleoli were inconspicuous. Some of the fragments were arranged in a small ball-like configuration in which there was cytoplasm resembling mesothelial cells [Figure 2]. Their three-dimensional nature and tight grouping set them apart from the loose sheets of mesothelial cells of the peritoneal wash. A few hemosiderin-laden macrophages were identified. A cytological diagnosis of endometriosis was made. Figure 1 Large endometrial fragment in peritoneal wash fluid showing epithelial lining on the outside, seen on the sides and as honeycombed cells as well as compact stromal cells within (PAP, ×400) Figure 2 Small spherule of endometrial cells in three-dimensional arrangement, which has to be differentiated from reactive mesothelial cells (PAP, ×400) The utility of peritoneal wash cytology for diagnosis of endometriosis has been reported.[1,2] In most cases, only hemosiderin-laden macrophages are identified.[2–5] The presence of endometrial cells is more specific but less sensitive than hemosiderin-laden macrophages for the diagnosis of endometriosis. The endometrial cells have been reported in 25%–52% of peritoneal washes done in endometriosis.[1,5] However, recognition of endometrial cells as well as hemosiderin-laden macrophages is essential for diagnosis on morphological basis alone.[6,7] The descriptions, diagnostic features and illustration of endometrial cell morphology in the peritoneal wash fluid is restricted to a few reports.[3,6] The distinction of endometrial cells from mesothelial cells and adenocarcinoma cells is important. Endometrial cells come in three-dimensional fragments that do not resemble mesothelial cells architecturally in washings which are arranged in sheets. However, endometriosis may elicit reactive mesothelial proliferation, which form three-dimensional fragments with calcific concretions, which are difficult to distinguish from endometrial cells.[5] Larger endometrial cell fragments may include stromal cells, which is a useful feature for differentiation as seen in the present case. Presence of hemosiderin-laden macrophages is indirect evidence of endometriosis. In the presence of an adnexal mass, a well-differentiated adenocarcinoma is always a diagnostic consideration and needs to be ruled out by the absence of atypia in the small cells and nuclei of endometrial cells. This distinction becomes difficult if there is reactive mesothelial proliferation in case of endometriosis.[2,5] The use of cell blocks and immunocytochemistry for epithelial and mesothelial cell markers can greatly aid diagnosis in distinction between reactive mesothelial fragments on one side and endometriosis and adenocarcinoma on the other.[2] Correlation with clinical and operative features is essential before cytological diagnosis.

Pineal concretions in turkey (Meleagris gallopavo) as a result of collagen-mediated calcification.

The intra-pineal calcification is a well-known phenomenon in mammals, however it is almost completely unknown in birds. The aim of the present work was to analyze morphology and genesis of the pineal concretions in the turkey. The studies were performed on the pineals collected from one-year-old turkeys (Meleagris gallopavo). In addition to standard morphological methods, the alizarin red S and potassium pyroantimonate methods were employed for localization of calcium at the light and electron microscopy level. In light microscopy, calcified concretions with diameters from 300 microm to 2 mm and quantities from 3 to 6 per gland were observed in all the examined pineals. They were stained red with alizarin S and showed the presence of collagen in Mallory's staining. Two types of cells were noted inside the concretion: polygonal and elongated ones. Using electron microscopy, three parts were distinguished within the calcification area. The peripheral part contained densely packed collagen fibrils, some elongated cells and numerous pyroantimonate precipitates demonstrating the presence of calcium ions. In the intermediate part, the fibrils were covered by almost continuous sheets of pyroantimonate precipitates and fused side by side. The central part showed an appearance of calcified hard tissue and contained some polygonal (osteocyte-like) cells. The obtained data demonstrated that the formation of the pineal concretions in the turkey is associated with the mineralization of collagen. This process is completely different from the mechanisms responsible for the formation of the concretions in the mammalian pineal.

Microcalcifications and Psammoma Bodies in Thyroid Tumors

Microcalcifications are a highly specific sign of malignancy being frequently detected in papillary or medullary cancers, while only 5% of nodular goiters and 3-4% of adenomas show this feature on thyroid sonogram. They correspond to clusters of psammoma bodies at cytological or histological examination. The microphotographs of cytological smears show psammoma bodies as 50 to 70 < m round-shaped calcific concretions with a glassy appearance, concentrically laminated.

Les tonsillolithes nasopharyngés au scanner : à propos de 31 cas

ObjectiveNasopharyngeal tonsilloliths are less well known to radiologists than palatine tonsil lithiases. The possibility of routinely available fine slices during CT scans of the head and neck prompted a retrospective study on the causes and radiological signs and patterns of nasopharyngeal tonsilloliths. Material and methodsA total of 515 CT scans were retrospectively re-examined looking for calcifications of the posterior wall of the nasopharynx. One patient with this type of calcification underwent a cerebral MRI as part of the etiological workup of his faintness, which also provided a study of the nasopharyngeal wall. The size, density, and position of these calcium concretions were analyzed with CT in all cases. ResultsIn 31 patients (18 men, 13 women), we discovered one or several calcifications in the pharyngeal mucous area, between 2 and 5.5 mm in size, with a median density of 202 HU. In two cases, we observed that these calcifications adhered to an adenoid cyst, whereas in three cases, the patients had both palatine tonsil and nasopharyngeal calcifications. None of the 31 patients had previously had an adenoidectomy. Sagittal CT and MRI images clearly localized all these calcifications before the pharyngobasilar fascia. DiscussionThe position of these nasopharyngeal calcifications in front of the pharyngobasilar fascia means that a calcified vestige of the notochord can be ruled out. Moreover, the simultaneous presence of nasopharyngeal tonsil and palatine tonsil calcifications in three patients is an additional argument for considering these calcifications of the posterior wall of the nasopharynx as tonsilloliths, all of which, representing 6 % of the CTs in our series, were asymptomatic. ConclusionThe nasopharyngeal tonsilloliths are stones less than 1 cm in size lodged in the pharyngeal tonsils that are frequently detected on CT when there are no clinical symptoms.

Pulmonary Alveolar Microlithiasis Scintigraphic Features

A 35-year-old female patient presented with a history of nonspecific chest pain and cough for one year. Spirometric studies excluded an obstructive ventilatory defect . Lung volume study findings were consistent with a moderate restrictive ventilatory defect with Total Lung capacity of 2.15L (51.6% of predicted). Diffusing capacity for the alveolar volume ventilated was reduced. Plain chest radiograph showed sand-like opacities, diffusely scattered, bilateral, micronodular areas of radioopacity of calcific densities throughout the lungs with the classic “sandstorm” pattern throughout both lungs predominantly in the lower zones (Fig: 1). Figure 1 Figure 1: Plain chest radiograph showing sand-like opacities, diffusely scattered, bilateral, micronodular areas of radioopacity of calcific densities throughout the lungs with the classic “sandstorm” pattern throughout both lungs predominantly in the lower zones. Computerized tomographic scan revealed diffuse bilateral calcified fine nodular pattern with extensive septal thickening (Fig: 2). Pulmonary Alveolar Microlithiasis Scintigraphic Features 2 of 4 Figure 2 Figure 2: Computerized tomographic scan showing diffuse bilateral calcified fine nodular pattern with extensive septal thickening. Figure 3 Figure 3: Tc-99m methylene diphosphonate (MDP) Bone scintigraphy showing intense bilateral uptake of the radiopharmaceutical in the lungs. Bone scintigraphy along with chest radiography and computerized tomography contributed to the diagnosis of Pulmonary Alveolar Microlithiasis in this patient. DISCUSSION Pulmonary alveolar microlithiasis is a rare disease of unknown etiology, characterized by the presence of calcific concretions in the alveolar spaces, intra-alveolar development and deposition of microliths or calcispherytes consisting of calcium phosphate1 The progression of the disease is generally very slow. Study of the calcium metabolism in many reported cases, however, reveals no derangement of serum calcium levels as in this patient who was normocalcemic, though elevated serum calcium and renal stones have been recorded in some cases.2, 3 Pulmonary function studies demonstrate a tendency toward a restrictive pattern. Chest roentgenography, high-resolution computed tomographic, and technetium-99m lung scan are useful in the diagnosis. Bone scintigraphy can be useful in the detection of early pulmonary calcifications, which have been associated with impaired pulmonary function and, due to their size, are generally not detected by X-ray. Bone scintigraphy may add helpful information in the case of nonspecific CT findings. Bone scan usually shows intense bilateral uptake of the radiopharmaceutical in the lungs.4 Differential diagnosis of diffuse lung uptake in bone scans includes patients with hyperparathyroidism, Hodgkins lymphoma, Sarcoidosis, Wegener's vasculitis, Primary amyloid, renal failure and Pneumocystis carinii.5 CORRESPONDENCE TO Dr Regi Oommen MD, Professor and Head, Department of Nuclear Medicine, Christian Medical College, Vellore - 632004, India. Email ID: regi@cmcvellore.ac.in Fax: 0091-416-2232103

Peritoneal Mice Implicated in Intestinal Obstruction

Peritoneal loose bodies or "peritoneal mice" are asymptomatic and mostly found as "incidentalomas" during intraperitoneal surgery or at autopsy. Implication of these concretions in an acute abdomen is a rare clinical entity. We report the case of a 63-year-old man who presented with small bowel obstruction and two calcified concretions in his pelvis. A computerized tomography scan demonstrated two oval stones near the terminal ileal loop with lumenal compression of the distal small bowel. During laparotomy, two extralumenal glistening stones, measuring 5.8 x 4.5 x 3.7 cm and 5.2 x 4.5 x 3.7 cm, were recovered from the peritoneal cavity. Histologically, the wall showed concentric lamellar fibrosis and calcification, whereas the nucleus displayed the vestiges of membranous fat necrosis; all consistent with diagnosis of peritoneal loose body. All symptoms of bowel obstruction were relieved postoperatively, and the patient had an uneventful recovery. Peritoneal loose body is a histopathologic diagnosis, and most other differentials for calcified intraperitoneal masses can be ruled out during the histologic examination. Surgical removal is recommended because conventional cross-sectional imaging cannot accurately establish the diagnosis.

Otolith matrix proteins OMP-1 and Otolin-1 are necessary for normal otolith growth and their correct anchoring onto the sensory maculae

Fish otoliths are highly calcified concretions deposited in the inner ear and serve as a part of the hearing and balance systems. They consist mainly of calcium carbonate and a small amount of organic matrix. The latter component is considered to play important roles in otolith formation. Previously, we identified two major otolith matrix proteins, OMP-1 ( otolith matrix protein-1) and Otolin-1, from salmonid species. To assess the function of these proteins in otolith formation, we performed antisense morpholino oligonucleotide (MO)-mediated knockdown of omp-1 and otolin-1 in zebrafish embryos. We first identified zebrafish cDNA homologs of omp-1 ( zomp-1) and otolin-1 ( zotolin-1). Whole-mount in situ hybridization then revealed that the expression of both zomp-1 and zotolin-1 mRNAs is restricted to the otic vesicles. zomp-1 mRNA was expressed from the 14-somite stage in the otic placode, but the zOMP-1 protein was detected only from 26-somite stage onwards. In contrast, zotolin-1 mRNA expression became clear around 72 hpf. MOs designed to inhibit zomp-1 and zotolin-1 mRNA translation, respectively, were injected into 1–2 cell stage embryos. zomp-1 MO caused a reduction in otolith size and an absence of zOtolin-1 deposition, while zotolin-1 MO caused a fusion of the two otoliths, and an increased instability of otoliths after fixation. We conclude that zOMP-1 is required for normal otolith growth and deposition of zOtolin-1 in the otolith, while zOtolin-1, a collagenous protein, is involved in the correct arrangement of the otoliths onto the sensory epithelium of the inner ear and probably in stabilization of the otolith matrix.

Sub-cellular partitioning of Cd, Cu and Zn in tissues of indigenous unionid bivalves living along a metal exposure gradient and links to metal-induced effects

We studied organ and sub-cellular distributions of several trace metals in a freshwater bivalve that has been proposed for use as a metal biomonitor. Specimens of Pyganodon grandis were collected from nine lakes located along a Cd, Cu and Zn concentration gradient (Rouyn-Noranda area, Québec). Gills and digestive gland were isolated, homogenized and six sub-cellular fractions were separated by differential centrifugation and analysed for their Cd, Cu and Zn content. Metallothionein was quantified independently. Gill tissues contained abundant calcium concretions that accounted for over 60% of the total gill burden of each metal. Cadmium and Zn concentrations in this granule fraction reflected ambient metal concentrations. Metal concentrations in the digestive gland also responded to the metal contamination gradient, but to a lesser extent than the gills, reflecting the lower abundance of granules in the digestive gland. Metals (Cd, Cu) in this organ were present largely in the “heat-stable proteins” fraction, and metal concentrations in this fraction were strongly correlated with those of both metallothionein and, to a lesser extent, the “lysosomes + microsomes” and “mitochondria” fractions. In both organs, Cd concentrations in the “heat-denaturable protein” fraction remained low and constant, suggesting reasonably effective metal detoxification. Some evidence for oxidative stress was noted in the gills but not in the digestive gland. Overall, we conclude that in nature metals in P. grandis are bound differently in the gills and in the digestive gland and that metal detoxification in the former organ may be less effective than in the latter.

Sub-cellular partitioning of metals (Cd, Cu, Zn) in the gills of a freshwater bivalve, Pyganodon grandis: role of calcium concretions in metal sequestration

Indigenous unionid molluscs, Pyganodon grandis, were collected from nine lakes in the Rouyn–Noranda area (Québec, Canada) along a polymetallic concentration gradient (Cd, Cu, Zn). After excision, the gills were gently homogenised and the cellular compartments were separated by a differential centrifugation procedure that yielded the following particulate fractions: “nuclei + cellular debris”, “mitochondria”, “lysosomes + microsomes” and “granules”. The supernatant remaining after the final ultracentrifugation step, i.e., the operationally-defined cytosol, was separated into a “heat-denaturable proteins” (HDP) fraction and a “heat-stable proteins” (HSP) fraction containing metallothionein (MT). The Cd, Cu and Zn content of each particulate and cytosolic fraction was determined and gill metallothionein was quantified independently by a mercury saturation assay. Cytosolic Cd concentrations were significantly related to the dissolved Cd concentrations at each site, but cytosolic Cu and Zn (essential metals) were not related to their respective ambient dissolved metal concentrations. Metallothionein concentrations increased along the metal contamination gradient and were related to cytosolic Cd (and Zn) in a concentration-dependent manner. However mass balance calculations showed that binding to metallothionein could only account for a small proportion of total gill metal (∼10% Cd; ∼3% Cu; ∼1% Zn). Under these chronic exposure conditions, the three metals (Cd, Cu and Zn) were mainly located in calcium concretions present in the gills (respectively 58 ± 13% of the total gill Cd, 64 ± 6% of the total gill Cu and 73 ± 6% of the total gill Zn). The overall contribution of granules to the total gill dry weight remained relatively constant among the different lakes, suggesting that lake-to-lake variations in granule synthesis were independent of the metal contamination gradient, i.e., these constituent elements of unionid gills act as non-inducible metal sinks at the cellular level. Metal concentrations increased proportionally in both the granules and the MT pool along the polymetallic gradient, suggesting a constant partitioning between these two compartments. Overall, despite an increase in Cd in the “mitochondria” fraction, metal sequestration mechanisms seem to be reasonably effective in detoxifying cadmium: in the cytosol, Cd concentrations in the potentially metal-sensitive HDP fraction remained relatively low and constant, even in specimens collected from the most contaminated lakes.

Cadmium-handling strategies in two chronically exposed indigenous freshwater organisms—the yellow perch ( Perca flavescens) and the floater mollusc ( Pyganodon grandis)

Laboratory experiments on a variety of aquatic organisms suggest that metallothionein-like proteins (MT) play an important role in the regulation of essential metals, and in the sequestration and detoxification of non-essential metals (e.g., Cd). However, the importance of metallothionein production relative to alternative strategies of metal detoxification, and its effectiveness in metal detoxification, remain largely unexplored in field situations. In the present study we explored metal-handling strategies in an adult benthic bivalve ( Pyganodon grandis) and in juvenile yellow perch ( Perca flavescens), exposed to Cd in their natural habitat. The two biomonitor species were collected from lakes located along a Cd concentration gradient. Ambient dissolved Cd concentrations were determined by in situ dialysis as a measure of metal exposure. Sub-cellular Cd partitioning was determined in target tissues (bivalve gills and digestive gland; perch liver) by differential centrifugation, and metallothionein was measured independently by a mercury-saturation assay in the bivalve tissues. Malondialdehyde concentrations were measured as a potential indicator of oxidative stress. Ambient dissolved Cd concentrations ranged from 0.06 to 0.57 nM in the nine lakes from which bivalves were collected, and from <0.3 to 6.7 nM in the eight lakes from which yellow perch were sampled. Bioaccumulated Cd also varied from lake to lake, more so for the bivalve than for the yellow perch; the [Cd] max/[Cd] min ratios for the various tissues decreased in the order: bivalve gill Cd (28) > bivalve digestive gland Cd (18) > perch hepatic Cd (14). In the two lakes that were common to both the bivalve and perch studies, i.e. lakes Opasatica and Vaudray, accumulated Cd concentrations were consistently higher in the bivalve than in the perch. Cadmium-handling strategies were similar in the bivalve digestive gland and perch liver, in that Cd was mainly associated with the heat-stable protein (HSP) fraction. Furthermore, in these organs the contributions from the “mitochondria” and “lysosomes + microsomes” fractions were consistently higher than in the gill tissue. In the bivalve gill, the HSP fraction could only account for a small proportion (10 ± 3%) of the total Cd burden, and the metal was instead largely sequestered in calcium concretions (58 ± 13%). Along the Cd-exposure gradient, Cd detoxification appeared to be reasonably effective in the bivalve gill and digestive gland, as judged from the protection of the heat-denaturable protein (HDP) fraction. However, in both organs Cd concentrations did increase in potentially metal-sensitive organelles (mitochondria), and malondialdehyde concentrations increased along the exposure gradient in the gills (but not in the digestive gland). Cadmium detoxification seemed less effective in juvenile yellow perch. As total hepatic Cd increased, Cd concentrations increased in all sub-cellular fractions, including the HDP fraction that was well protected in the bivalve. The relative proportions of Cd in the various fractions did not vary appreciably along the exposure gradient and there was no evidence of a threshold exposure concentration below which sensitive metal pools were protected.

Absence of pulmonary uptake of tc-99m methylenediphosphonate in alveolar microlithiasis

Pulmonary alveolar microlithiasis (PAM) is a rare disease of unknown etiology characterized by accumulation of calcific concretions in the alveolar spaces. The paper reports a case of PAM in a 56-year-old male. The patient had persistent dry cough, and gradually progressive dyspnea on exertion. The diagnosis was established on the basis of roentgenography and confirmed by the sputum and transbronchial biopsy findings. Scintigraphy revealed the absence of Tc-99m methylenediphosphonate uptake of lungs. Familial occurrence was not observed. Chest roentgenogram, pulmonary function, and clinical status of the patient have remained stable for 41 months. Radiological and clinical follow-up of the disease continues.

Pulmonary Alveolar Microlithiasis: A Case Report

Pulmonary alveolar microlithiasis is a rare disease of unknown etiology, characterized by intra-alveolar deposition of calcific concretions. Chest radiographic findings are characteristic, showing multiple nodules less than 1 mm diameter scattered diffusely throughout the lung parenchyma. Pulmonary alveolar microlithiasis is a slowly progressive disease leading to respiratory insufficiency associated with cyanosis, clubbing, and pulmonary hypertension. There is no satisfactory therapy for this condition.

Sub-cellular partitioning of essential and non-essential metals in a freshwater mollusc,Pyganodon grandis, collected in the field along a polymetallic environmental gradient

The cellular alterations normally induced by metals at high concentrations can be prevented by detoxification processes [1] such as sequestration into cellular compartments (calcium concretions, lysosoiues, etc.) or their binding to specific cellular ligands like metallothionein [2]. The aim of this project was to study and compare the subcellular partitioning of three metals (Cd. Cu, Zn) in gills of a freshwater molluse, Pyganodon grandis, collected along a polymetallic environmental gradient (nine lakes in the Rouyn-Noranda area, Abitibi, QC, Canada). Differential centrifugation was used to partition metals among different subcellular fractions. In the gills, along the environmental metal gradient, total tissue metal concentrations were positively correlated with concentrations in the granule traction; gill tissues contained high amounts of calcium concretions, which acted as preferential sites for sequestration of the three metals. An increase in Cd concentration was observed in the heat stable proteins fraction (including metallothionein), but not in the heat-denatured proteins fraction, suggesting that Cd-induced cell injury could be prevented by the involvement of maltiple cellular compartments in a protective role.

Evaluation of testicular microlithiasis in varicoceles.

Background: Testicular microlithiasis is said to be characterized by calcific concretions within the seminiferous tubules. There have been reports suggesting a link between testicular microlithiasis and testicular dysfunction and tumors. Methods: In this study, we assessed subjects with varicoceles detected by using testicular ultrasound, and evaluated the cases of testicular microlithiasis in terms of age, seminalysis findings, and endocrinological parameters (testosterone, follicular stimulating hormone (FSH), luteinizing hormone (LH), and prolactin (PRL)). The subjects comprised 224 patients with varicoceles diagnosed by using testicular ultrasound, who attended this institution as outpatients between January 1998 and August 2000. Results: Testicular microlithiasis was detected in 15 out of 224 subjects (6.7%), bilateral in all cases. No significant differences were seen between the group with testicular microlithiasis and the group without testicular microlithiasis, in terms of age, seminalysis findings, and/or endocrinological parameters (testosterone, FSH, LH, prolactin). The incidence of testicular microlithiasis in outpatients undergoing testicular ultrasound varies between reports, but is of the order of 0.6-2.0%. Conclusion: In this study, we found a high proportion of testicular microlithiasis at 6.7%, strongly suggesting a link with male infertility. (Reprod Med Biol 2002; 1: 75-79).

Excitatory amino acids and neurodegeneration: a hypothetical role of calcium precipitation

Activation of excitatory amino acid (EAA) receptors can induce neurodegeneration by two major mechanisms of excitotoxicity, one related to the influx of Na+, Cl− and water, and the other to the increase in intracellular calcium concentration ([Ca2+]i). Thus, acute microinjection of EAAs in several areas of the central nervous system (CNS) has been used to produce neurodegenerative models. We studied the excitotoxic pattern associated with acute microinjection of AMPA in rat hippocampus, medial septum-diagonal band of Broca (MS-DBB), prefrontal cortex and retina. In all cases progressive neuronal loss, glial reaction and development of intra- and extracellular calcium concretions were observed. However, a CNS-area differential vulnerability was revealed, as shown by the specific atrophy of MS-DBB and its limited calcification. Whether calcium deposits are a defensive mechanism against the massive increment of free cytoplasmatic calcium is discussed on the basis of ultrastructural data and previous results.

Long-term effects of α-amino-3-hydroxy-5-methyl-4-isoxazole propionate and 6-nitro-7-sulphamoylbenzo(f)quinoxaline-2,3-dione in the rat basal ganglia: calcification, changes in glutamate receptors and glial reactions

Previous data from our laboratory indicate that 25 mM ibotenic acid induces intracellular calcifications in the rat basal forebrain. Because of the lack of specificity of ibotenic acid for a glutamate receptor subtype, a dose–response study with α-amino-3-hydroxy-5-methyl-4-isoxazole propionate was undertaken and calcified areas (identified with Alizarin Red staining) as well as astro- and microglial reactions (by autoradiography with [ 3H]lazabemide and [ 3H]Ro 5-4864) were quantified at one month post-lesion. α-Amino-3-hydroxy-5-methyl-4-isoxazole propionate administered into the globus pallidus induced, in a dose-dependent manner, the formation of calcium deposits and the activation of both glial cells, the microglial reaction being particularly robust. From this study, a dose of 5.4 mM α-amino-3-hydroxy-5-methyl-4-isoxazole propionate was selected for further experiments. [ 3H]α-amino-3-hydroxy-5-methyl-4-isoxazole propionate, [ 3H]dizocilpine maleate and [ 3H]PN 200-110 binding in vitro were performed to assess autoradiographically whether the tissue damage was associated with changes in glutamate receptors and calcium channel binding sites. In the α-amino-3-hydroxy-5-methyl-4-isoxazole propionate-treated animals, the specific binding of [ 3H]α-amino-3-hydroxy-5-methyl-4-isoxazole propionate was significantly reduced by 28% in the lesioned ventral pallidum, whereas it was unchanged in the globus pallidus and substantia innominata. In these three nuclei, calcifications developed and an increase in both glial markers was measured. In contrast, the binding of [ 3H]PN 200-110 and [ 3H]dizocilpine maleate were unaffected. Co-injection of 15 mM 6-nitro-7-sulphamoylbenzo(f)quinoxaline-2,3-dione, a selective α-amino-3-hydroxy-5-methyl-4-isoxazole propionate/kainate receptor antagonist, prevented the formation of calcium concretions, the microglial reaction and the decrease in [ 3H]α-amino-3-hydroxy-5-methyl-4-isoxazole propionate binding but it failed to inhibit totally the astroglial reaction induced by α-amino-3-hydroxy-5-methyl-4-isoxazole propionate. This may suggest that the microglial reaction and calcification take place through different mechanisms from the astrogliosis associated with the neuronal loss. In conclusion, acute administration of α-amino-3-hydroxy-5-methyl-4-isoxazole propionate in the rat globus pallidus elicits a dose-dependent calcification process associated with a chronic reaction of astrocytes and microglia. α-amino-3-hydroxy-5-methyl-4-isoxazole propionate-induced injury is accompanied by a slight reduction of α-amino-3-hydroxy-5-methyl-4-isoxazole propionate receptors in the ventral pallidum, whereas the binding of N-methyl- d-aspartate and L-type calcium channels receptors remains unchanged in any lesioned nucleus.

Microcalcifications in the anterior pituitary gland of the fetus and the newborn: A histochemical and immunohistochemical study

Calcified concretions are a normal and constant finding in the anterior pituitary gland of fetuses and newborns. Their light and electron microscopic characteristics have been recently reported by the authors. In this study, undecalcified and decalcified sections from 20 neonatal and 60 fetal anterior pituitary glands were studied by histochemical and immunohistochemical methods to further clarify their nature and mechanism of formation. All the glands revealed homogeneous and/or laminar calcifications located either within the interstitium or follicular structures. They were composed of a diastase-resistant periodic acid-Schiff—positive carbohydrate-rich matrix. The Feulgen method for DNA was negative. Their core frequently reacted to Alcian blue and epithelial membrane antigen (EMA). EMA also stained the apical membranes of adjacent epithelial cells. Other immunostains (vimentin, keratin, and pituitary hormones) were negative. The positive staining for Alcian blue and EMA and the negative staining with the Feulgen method for DNA suggest that the core of the calcifications consists of acidic mucosubstances and EMA-positive proteinaceous material previously secreted by viable pituitary cells. The EMA-negative periphery of the concretions probably develops from further extracellular peripheral mineralization that leads to larger, sometimes laminated psammoma bodies. The occurrence of pituitary calcifications in states of adult physiological and pathological hyperprolactinemia suggests that the marked proliferation of lactotrophs occurring during the fetal life play an important role in the pathogenesis of the fetal and neonatal concretions.