A new scoring system using multiple immunohistochemical markers for diagnosis of uterine smooth muscle tumors

The diagnosis of uterine smooth muscle neoplasms by light microscopy is difficult. Multiple classification schemes have been proposed based on mitotic rate, nuclear atypia, and the presence or absence of necrosis. None of these classification systems has been entirely successful. This study was undertaken to evaluate the use of selected immunohistochemical and histochemical markers in differentiating these tumors, in addition to accepted morphologic criteria. Ten cases of each of the following: leiomyosarcomas (LMS), atypical leiomyomas (AL), cellular leiomyomas (CL) and usual leiomyomas (UL), were classically evaluated for histological diagnosis and were stained for Ki-67 (MIB-1), bcl-2 and p53 using monoclonal antibodies and the avidin-biotin peroxidase method, and argyrophilic nucleolar organizer region (AgNORs). The number of stained cells was counted in the most positively stained region in a 4 mm² square cover glass mounted on each slide. The mean value was calculated for each group of tumors. The data for Ki-67 (MIB-1), bcl-2, p53 and AgNOR staining respectively, were significantly higher in LMS by comparison to UL, CL or AL. Because many singular cases had superimposed data being difficult to diagnose, a new scoring system for pathological evaluation was created. The results obtained by this scoring system suggest that immunohistochemical markers Ki-67 (MIB-1), bcl-2, p53 together with the AgNOR staining could be useful, by the scoring system, as an adjunct to the current accepted morphologic criteria in differentiating smooth muscle tumors of the uterus.

The structure of mast cell secretory granules in the blind mole rat (Spalax ehrenbergi)

Eosinophils, basophils, and mast cells produce and secrete active substances whose role is to attack invading parasites and protect the host. In this study we use morphometric methods to study mast cells in the blind mole rat (Spalax ehrenbergi). The subterranean and solitary way of life of this species has led to the evolutionary development of special anatomical, morphological, behavioral, and physiological adaptations. Because of its particular lifestyle, the mole rat is less exposed to parasites than other rodents. This could provide a unique model for research into the pathobiology of mast cells. The paracrystalline structure of the mast cell granule content is composed of parallel plates. Diffraction analysis of electron micrographs of thin sections of araldite-embedded tissues indicated that each crystal line plate is a periodic array of parallelograms. The crystal unit cell volume is approximately 930 nm(3), suggesting that each unit cell is composed of one heparin molecule and one to three additional adsorbed proteins. Morphometric data show that characteristics of the secretory granules of mast cells of the blind mole rat resemble those of other rodents. The mast cell unit granule volume in the present study was calculated to be 0.055 microm(3), similar to that of rat peritoneal mast cells.

Changes in the distribution of anionic constituents in secretory granules of mouse pancreatic acinar cells after pilocarpine-induced degranulation

We used cationized colloidal gold (CCG) to investigate the distribution of anionic sites in different secretory granules of mouse pancreatic acinar cell regranulation. Localization of anionic sites with CCG was carried out on ultrathin sections of a mouse pancreas, fixed in Karnovsky's fixative and OsO4 and embedded in Araldite. After pilocarpine-stimulated degranulation, there was a marked diminution in the anionic charge density of immature and mature granules of the 4-hr group (approximately 43.0 gold particles/microm2) compared to the 8-hr mature granules group (approximately 64.6 gold particles/microm2). Scattergram analysis to investigate the correlation between section profile size and cationized gold labeling density revealed a reverse correlation, the small granule profiles demonstrated a higher density compared to the larger profiles of the same group. On the basis of these observations, it appears that a post-translational processing of secretory content influences the granule anionic charge and thus may affect the intragranular buffer capacity.

Evaluation of atrial natriuretic peptide and brain natriuretic peptide in atrial granules of rats with experimental congestive heart failure

The natriuretic peptides are believed to play an important role in the pathophysiology of congestive heart failure (CHF). We utilized a quantitative cytomorphometric method, using double immunocytochemical labeling, to assess the characteristics of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) in atrial granules in an experimental model of rats with CHF induced by aortocaval fistula. Rats with CHF were further divided into decompensated (sodium-retaining) and compensated (sodium-excreting) subgroups and compared with a sham-operated control group. A total of 947 granules in myocytes in the right atrium were analyzed, using electron microscopy and a computerized analysis system. Decompensated CHF was associated with alterations in the modal nature of granule content packing, as depicted by moving bin analysis, and in the granule density of both peptides. In control rats, the mean density of gold particles attached to both peptides was 347.0 +/- 103.6 and 306.3 +/- 89.9 gold particles/microm2 for ANP and BNP, respectively. Similar mean density was revealed in the compensated rats (390.6 +/- 81.0 and 351.3 +/- 62.1 gold particles/microm2 for ANP and BNP, respectively). However, in rats with decompensated CHF, a significant decrease in the mean density of gold particles was observed (141.6 +/- 67.3 and 158.0 +/- 71.2 gold particles/microm2 for ANP and BNP, respectively; p<0.05 compared with compensated rats, for both ANP and BNP). The ANP:BNP ratio did not differ between groups. These findings indicate that the development of decompensated CHF in rats with aortocaval fistula is associated with a marked decrease in the density of both peptides in atrial granules, as well as in alterations in the quantal nature of granule formation. The data further suggest that both peptides, ANP and BNP, may be regulated in the atrium by a common secretory mechanism in CHF.

Decelerated rate of dendrite outgrowth from dopaminergic neurons in primary cultures from brains of hypoxanthine phosphoribosyltransferase-deficient knockout mice

Lesch-Nyhan syndrome (LNS), caused by the complete deficiency of hypoxanthine phosphoribosyltransferase (HPRT), is characterized by a neurological deficit, the etiology of which is still unclear. Evidence has accumulated indicating that it reflects dopamine deficiency associated with defective arborization of dopaminergic dendrites. We monitored the differentiation in vitro of dopaminergic neurons, cultured from HPRT-deficient knockout mice. The HPRT-deficient dopaminergic neurons exhibited a decelerated rate of outgrowth of dendrites in comparison to that of control neurons resulting, after 8 days in culture, in 32% smaller average total length of dendrites per neuron (P<0.025). The results suggest that the abnormal dendrite outgrowth in LNS reflects a defective developmental process.

Histopathology of the inferior turbinate with compensatory hypertrophy in patients with deviated nasal septum

OBJECTIVE

To measure the dimensions, composition, and possible structural and/or histopathological changes of the compensatory hypertrophic inferior turbinate in patients with deviated nasal septum.

STUDY DESIGN

A prospective, nonrandomized, and morphometric study.

METHODS

Nineteen patients with deviated nasal septum and compensatory hypertrophy of the inferior turbinate in the contralateral nasal cavity underwent surgery for correction of nasal obstruction. Patients' specimens were compared with those of a control group consisting of 10 inferior turbinates removed at autopsy. Quantitative measurements of the inferior turbinate histological sections were carried out and included the width of the layers and morphometric calculations of the relative proportions of the soft tissue constituents. Also, qualitative study was performed to detect pathological changes.

RESULTS

Of all layers, the inferior turbinate bone underwent a twofold increase in thickness and manifested the most significant expansion (P < or =.001), whereas the contribution of the mucosal layers to the inferior turbinate hypertrophy was modest. The morphometric analysis revealed a larger proportion of venous sinusoids in hypertrophic turbinates, but the difference was small and statistically insignificant. Qualitative assessment disclosed normal mucosal architecture in all inferior turbinates with compensatory hypertrophy. Eleven remained intact, while eight disclosed mild to moderate pathological changes.

CONCLUSIONS

The data gathered in the present study are of importance to the decision-making process regarding turbinate surgery. The significant bone expansion and the relative minor role played by the mucosal hypertrophy would support the decision to excise the inferior turbinate bone at the time of septoplasty.

Maturation phenotype of Sertoli cells in testicular biopsies of azoospermic men

The involvement of Sertoli cells in different spermatogenic impairments has been studied by an immunohistomorphometric technique using cytokeratin-18 (CK-18) as a marker for immature Sertoli cells. CK-18 is known to be expressed in Sertoli cells during prenatal and prepubertal differentiation and is normally lost at puberty. Forty-nine azoospermic men were included in the current study. Quantitative measurements on testicular biopsies revealed the highest CK-18 expression in the mixed atrophy biopsies (22 men), a lower expression in the Sertoli cell-only (SCO) biopsies (12 men), and minimal residual staining in the group considered as representing normal spermatogenesis (six obstructive azoospermia patients). The cytokeratin immunopositive-stained tubules were associated either with arrest in spermatogenesis or with SCO. Examination of sections from nine men with microdeletions in the AZF region of the Y chromosome revealed that these men were either negative for CK-18 expression or showed only weak residual staining. This may suggest that the spermatogenic defect in the AZF-deleted men originates in the germ cell and has no impact on Sertoli cell maturation. The cause that determined the spermatogenic defect in the other cases of male infertility with high CK-18 expression may have damaged both the Sertoli and the germ cells.

Effect of photoperiod variation on testes and accessory sex organs in the male blind mole rat Spalax ehrenbergi

The blind mole rat is a seasonally breeding fossorial rodent that is perceptionally blind. This study examines the effect of photoperiod on the morphology and histology of the male mole rat reproductive system, three groups of male mole rats were maintained in the laboratory under short day (SD) conditions (9L: 15D); long day (LD) conditions (15L:9D); and constant darkness (CD), and compared to animals trapped in the field (FL). It was found that the field animals revealed higher testes and prostate gland weights, higher prostate tubuli volume (v*) and lower testes tubuli volume (v*) compared to the other three groups. Distribution of the tubuli in the testes (Vv) was low in the FL group compared to the SD and LD groups but still higher than in the CD group. Distribution of lumen in the testes (Vv) was higher in the CD group in comparison to the other three groups. Distribution of interstitial tissue in the testes (Vv) was higher in the FL group than in the other three groups. Electrolytes and elements secreted from the prostate gland did not differ among the four groups. In the FL group distribution of the tubuli (Vv) in the prostate gland was low and lumen ratio (Vv) was high compared to the other three groups. Distribution of connective tissue in the prostate gland did not differ among all four groups. Testosterone levels and total sperm count was highest in the FL group. Sperm production was noted in all groups; however spermatid and spermatozoa cell production was higher in the FL group. This study shows that photoperiod could be important in initiating timing in the breeding season but that certain other conditions which are absent in the laboratory appear to be responsible for successful breeding in the field.

Differential expression of p53 and Ki-67 proteins in classic and iatrogenic Kaposi's sarcoma

In many neoplasms, the finding p53 immunoreactivity correlates with striking cytologic atypia, a high tumor cell proliferation rate, and poor prognosis. The literature regarding p53 and Ki-67 (a nuclear proliferation-associated antigen) immunoreactivity in Kaposi's sarcoma is limited. We aimed to: (1) evaluate the role of p53 in the development of Kaposi's sarcoma; (2) determine whether there is a correlation between p53 and Ki-67 protein expression; and (3) determine possible differences between classical Kaposi's sarcoma, known usually to have a benign course, and iatrogenic Kaposi's sarcoma, the course of which is unpredictable, by studying the differential expression of p53 and Ki-67. Among 26 cases of classic KS and 19 of iatrogenic KS, 12 were classified histopathologically as early type and 33 as mixed or spindle-cell type. P53 and Ki-67 immunoreactivity correlated significantly with the histopathologic stage of KS (r=0.63, p=0.0001; r=0.42, p=0.0084, respectively). P53 was not detected in any of the cases in an early histopathologic stage but was present in 55% of the cases in a more advanced stage. The spindle cells increased in proportion with the histopathologic progression and were more often positive (p=0.019) and displayed more extensive staining than the endothelial cells (p=0.0001). There was a strong positive correlation between p53 and Ki-67 protein expression (r=0.43, p=0.0087). There was no correlation between the expression of either p53 or Ki-67 and the extent of the eruption. The expression of p53 and Ki-67 was significantly lower in iatrogenic cases than in the classic cases (p=0.009, p=0.0014, respectively), although no statistical difference was found between the histopathologic stages in the two clinical forms of KS. P53 immunoreactivity was detected in 79% of the cases of classic Kaposi's sarcoma in the mixed or spindle cell stage but in only 21.5% of the iatrogenic cases showing the same histopathologic stage (p=0.001), and the percentage of spindle cells as well as the endothelial cells expressing p53 was higher in the classic cases than in the iatrogenic cases (p=0.0032, p=0.0142, respectively). We conclude that p53 immunoexpression is a marker of tumor progression in classic Kaposi's sarcoma but not in most cases of iatrogenic Kaposi's sarcoma. The proliferative activity of the tumor cells in classic Kaposi's sarcoma is much higher than in iatrogenic Kaposi's sarcoma. Our work implies that the molecular steps involved in classic and iatrogenic Kaposi's sarcoma differ.

Pathways of macromolecular extravasation across microvascular endothelium in response to VPF/VEGF and other vasoactive mediators

OBJECTIVE

The goal of these studies was to define the anatomic pathways by which circulating macromolecules extravasate from the hyperpermeable microvessels that supply tumors and from normal venules that have been rendered hyperpermeable by vasoactive mediators.

METHODS

Extravasation pathways of circulating macromolecular tracers were followed by several morphological techniques: light and fluorescence microscopy, transmission electron microscopy of routine as well as ultrathin and serial sections, computer-assisted three-dimensional reconstructions, and morphometry.

RESULTS AND DISCUSSION

Macromolecules extravasated across tumor microvessels or across normal venules rendered hyperpermeable by VPF/VEGF, histamine, or serotonin by three primary pathways: 1) Vesiculo-vacuolar organelles (VVOs), clusters of cytoplasmic vesicles and vacuoles that span endothelial cytoplasm from lumen to ablumen; 2) trans-endothelial cell (EC), pores, and 3) fenestrae. We also present data concerning the structure and function of VVOs as well as evidence that VVOs form as the result of linking together and fusion of caveolae-sized unit vesicles. Under suitable conditions VVOs also afforded a pathway for macromolecular transport in the reverse direction, i.e., from vascular ablumen to lumen. Finally, in addition to opening VVOs to the passage of macromolecules, mediators such as VPF/VEGF may also induce structural rearrangements of VVOs, transforming them into trans-EC pores or fenestrae.

The peritoneal membrane in peritoneal dialysis patients: estimation of its functional surface area by applying stereologic methods to computerized tomography scans

The surface area of the peritoneal membrane in contact with dialysate is an important determinant of solute transport across the peritoneum. Yet there is no method for its estimation in peritoneal dialysis patients. In this study, stereologic methods were applied to computerized tomography (CT) imaging of the peritoneal membrane to estimate the peritoneal membrane surface area. The method was first validated by implementing stereologic methods on a phantom of known surface area. The phantom was a distorted bottle filled with contrast media. Series of thin helical CT sections were performed, and random sections were obtained after reconstruction. A transparent counting grid was placed over the random sections. The surface area was estimated using 9, 18, and 36 random sections. To calculate the coefficient of variation (CV) of the method, 20 different combinations of 9, 18, and 36 random sections were used. With 36 random sections, the error in estimation of the bottle's surface area was -9.4% to +8.8%. The CV was 5.0%. Decreasing the number of sections used to 18 and 9 yielded a CV of 7.8 and 12.3%, respectively. This method was then applied to the peritoneal membrane, which was visualized by instilling dialysate containing contrast media into the peritoneal cavity of peritoneal dialysis patients. The estimated peritoneal membrane surface area of six patients was 0.55 +/- 0.04 m2. This novel method permits the measurement of the peritoneal membrane surface area with a high degree of accuracy.

Morphometric studies of secretory granule formation in mouse pancreatic acinar cells. Dissecting the early structural changes following pilocarpine injection

Secretory granule formation in pancreatic acinar cells is known to involve massive membrane flow. In previous studies we have undertaken morphometry of the regranulation mechanism in these cells and in mast cells as a model for cellular membrane movement. In our current work, electron micrographs of pancreatic acinar cells from ICR mice were taken at several time points after extensive degranulation induced by pilocarpine injection in order to investigate the volume changes of rough endoplasmic reticulum (RER), nucleus, mitochondria and autophagosomes. At 2-4 h after stimulation, when the pancreatic cells demonstrated a complete loss of granules, this was accompanied by an increased proportion of autophagosomal activity. This change primarily reflected a greatly increased proportion of profiles retaining autophagic vacuoles containing recognisable cytoplasmic structures such as mitochondria, granule profiles and fragments of RER. The mitochondrial structures reached a significant maximal size 4 h following injection (before degranulation 0.178 +/- 0.028 microm3; at 4 h peak value, 0.535 +/- 0.109 microm3). Nucleus size showed an early volume increase approaching a maximum value 2 h following degranulation. The regranulation span was thus divided into 3 stages. The first was the membrane remodelling stage (0-2 h). During this period the volume of the RER and secretory granules was greatly decreased. At the intermediate stage (2-4 h) a significant increase of the synthesis zone was observed within the nucleus. The volume of the mitochondria was increasing. At the last step, the major finding was a significant granule accumulation in parallel with an active Golgi zone.

Mechanisms leading to cortical reaction in the mammalian egg

Activation of the mammalian egg results in cortical reaction (CR), which is correlated with an increase in intracellular Ca2+ concentration and PKC activation. The CR is a gradual rather then an "all or none" response, and can be regulated by different concentrations of parthenogenetic activators. To evaluate the biological significance of parthenogenetic induced CR, rat eggs were fertilized or activated by different concentrations of ionomycin and TPA. Cortical granules (CG) were monitored by electron microscopy, while the CG exudate was visualized by Lens culinaris lectin and Texas Red, using light and confocal microscopy. The ability of the CR to trigger a full block to polyspermy was examined in an IVF system. Our study demonstrates the existence of light and dark CG, which differ by number, distribution in the egg cortex, and sensitivity to parthenogenetic activators. Sperm penetration or high concentration of activators, trigger depletion of both light and dark CG, leading to a full CR. Low concentration of activators altered the CG density, the ratio of dark/light CG, and induced partial CR that was sufficient to cause a block to polyspermy. The results imply that Ca2+ rise or PKC activation have different effects on light and dark CG. In recently fertilized or parthenogenetically activated eggs, CG exudate appeared as evenly distributed spots, whereas in more advanced stages of fertilization the exudate was scattered as patchy aggregates. This observation suggests a difference in the dispersion of CG exudate after fertilization as compared to parthenogenetic activation.

Defective cytoplasmic granule formation.II. Differences in patterns of radiolabeling of secretory granules in beige versus normal mouse pancreatic acinar cells after [3H]glycine administration in vivo

We investigated the development of secretory granules in the pancreatic acinar cells of normal (C57BL/6J +/+) and beige (C57BL/6J Lystbg/Lystbg) mice by analyzing the distribution of 3H label in pancreatic acinar cells after a pulse of [3H]glycine administered in vivo. The results provide quantitative confirmation of the hypothesis that the maturation of condensing vacuoles/immature granules to mature granules in pancreatic acinar cells is associated with a significant volume reduction. Beige mice differ from control mice by exhibiting a more rapid distribution of 3H label from the rough endoplasmic reticulum-rich cytoplasm to the secretory granules and a slightly faster rate of maturation of 3H-labeled granules. Beige mouse pancreatic acinar cells also exhibited, as early as 1 h after pulsing with [3H]glycine, a much higher proportion of 3H-labeled secretory granules than did the cells of control mice. These findings identify additional abnormalities in secretory granule formation in pancreatic acinar cells which are related to the beige (Lystbg) mutation and provide support for the hypothesis that beige mice exhibit an abnormal pattern of granule-granule fusion.

Determination of mean particle volume, a Monte Carlo simulation

Either length measurements or area measurements may be made on a sample of profiles for the purpose of estimating the mean volume of a population of convex particles. Diameters of spheres, caliper diameters of ellipsoids and intercept lengths are available length measurements. Profile areas can be evaluated by planimetry or point counting. Either all the available profiles in random sections or point sampled profiles can be utilized. We have applied a Monte Carlo simulation to compare several of the stereologic methods for the estimation of the mean volumes of spheres and ellipsoids. Populations of spherical, prolate ellipsoidal and oblate ellipsoidal particles were subjected to random sectioning and measurement. Diameter, point sampled intercept length, area and point sampled area were measured in the case of the spherical particles. With the ellipsoids, the same measurement excepting diameters were performed. The measurements were converted to volumes by the appropriate equations, and the means, the standard deviations of the means and the 95% confidence intervals were determined for increasing sample sizes. All the methods provide estimates that converge on their theoretical mean volumes. The area measurements and particularly the point sampled area measurement show some advantage over the length measurements, but differences among the methods are small, not entirely consistent over the different cases and unlikely to be significant in most real applications.

Evidence for endogenous ADP-ribosylation of GTP-binding proteins in neuronal cell nucleus. Possible induction by membrane depolarization

GTP-binding protein(s) recognized by antibodies against the alpha-subunits of Gi- and Go-proteins were detected in crude nuclei isolated from rat brain stem and cortex. Immunohistochemical staining indicated that in the cortex these proteins are perinuclear, or are embedded in the nuclear membrane. Evidence is presented for an endogenous ADP-ribosylation of these proteins, which competes with their PTX-catalyzed ADP-ribosylation. The endogenous reaction has the characteristics of nonenzymatic ADP-ribosylation of cysteine residues, known to involve NAD-glycohydrolase activity. In vitro experiments showed that the alpha-subunit of Go-proteins in the cell membrane also acts as a substrate of this endogenous ADP-ribosylation. The in situ effect of membrane depolarization on the nuclear GTP-binding proteins may be attributable to their depolarization-induced endogenous ADP-ribosylation, suggesting a novel signaling mechanism in neuronal cells in the central nervous system.

Quantitative microscopic changes in the mole rat's accessory sex organs during an annual cycle

BACKGROUND

The mole rat, Spalax ehrenbergi, is a solitary, aggressive subterranean rodent. The present study summarizes a year-round investigation of morphological changes in the mole rat's accessory sex organs.

METHODS

Mole rats maintained in the laboratory were killed after 3 months of acclimation; additional animals trapped in the wild were killed immediately. The accessory sex organs were processed for routine histological examination. Tissues were fixed in Bouin's solution, embedded in paraffin blocks, and stained by hematoxylin-eosin. A systemic sampling approach was used to photomicrograph the tissues for histomorphometric assessment.

RESULTS

The volume fraction (Vv, mean +/- SEM) of prostate connective tissue from animals kept in captivity increased significantly in January (0.49 +/- 0.05 mm3/mm3) and April (0.43 +/- 0.04 mm3/mm3) but only 0.26 +/- 0.03 mm3/mm3 in November. In the field group, the Vv of prostate connective tissue was significantly higher in January (0.58 +/- 0.08 mm3/mm3) and April (0.62 +/- 0.08 mm3/mm3) and lower in November (0.44 +/- 0.03 mm3/mm3) and February (0.43 +/- 0.03 mm3/mm3), with a concomitant decrease in prostate tubuli and lumen. The prostate tubuli star volume (v*) in laboratory animals increased in November (0.009 +/- 0.002 mm3) and May (0.09 +/- 0.02 mm3). The same pattern was shown in the field group, with a significant increase in December (0.012 +/- 0.002 mm3) and March (0.007 +/- 0.001 mm3). The Cowper tubuli Vv in the captive animals increased during February (0.24 +/- 0.02 mm3/mm3), with a concomitant reduction in the connective tissue (0.05 +/- 0.02 mm3/mm3). The Cowper tubuli v* in same animals increased in December, April, and July (1.37 +/- 0.18 x 10(-4) mm3, 0.94 +/- 0.10 x 10(-4) mm3, 1.52 +/- 0.20 x 10(-4) mm3, respectively). In field group, a slight decrease in star volume took place from November to May (1.25 +/- 0.16 mm3 to 0.39 +/- 0.05 mm3, respectively). Testosterone levels appeared to be higher in the field group than in the laboratory group. In December the values were 1.62 +/- 0.15 ng/ml in the field group and 0.55 +/- 0.12 ng/ml in the laboratory group, and in May the laboratory group values were 1.66 +/- 0.12 ng/ml.

CONCLUSIONS

In captivity and in the field, male mole rats probably undergo an annual cycle of accessory gland tissue structural changes that are correlated with testosterone secretion.

Quantitative histomorphology of the blind mole rat harderian gland

Anatomical, histological and morphometric studies have been performed on the harderian gland and its surroundings in the blind mole rat (Spalax ehrenbergi). The gland is tubuloalveolar with no true duct system. All ducts within the gland are formed by a single epithelial cell type and drain into a wide secretory duct. This opens into the conjunctival sac which serves as a reservoir for harderian secretions. Drainage from the conjunctival sac follows 2 possible routes: one through the nasolacrimal duct to the external nasal cavity, the other through a unique excretory duct that emerges from the anteromedial part of the conjunctival sac and runs through the dermis to the skin, opening at the base of a hair follicle. The function of this newly described duct is discussed. Morphometric studies revealed that the lumen volume fraction in the female, slightly smaller than that of the male during the summer, becomes significantly greater during the winter breeding season. The dimorphism and seasonal variations found in the gland acini suggests that the gland may be implicated in pheromone production.

An histochemical approach to characterization of anionic constituents in mast cell secretory granules

We used cationized colloidal gold in order to investigate the distribution of anionic sites in different secretory granules of rat and mouse mast cells. The localization of the anionic sites was performed by post-embedding labeling of thin sections of rat peritoneal cells or mouse skin tissue, fixed in Karnovsky's fixative and OsO4, and embedded in Araldite or LR white, respectively. In all cases anionic sites were demonstrated with a high density variation depending on cell type. In all mast cell secretory granules we have observed the highest density (ca. 500-900 gold particles/microns2), while in other peritoneal cell granules it was about 10 times less (ca. 40-80 gold particles/microns2). Pretreatment of the LR white sections with heparinase I and III resulted in a reduction of 97% and 72%, respectively, in the binding of the gold particles to the granules, indicating that the majority of the gold binding reactivity is due to heparin. Correlation of section profile area with labeling density revealed that the smaller granules were significantly more labeled when compared to the larger profiles. On the basis of these observations it seems that a post-translational change (mainly sulfation of heparin) of secretory content influences the granule anionic charge and thus may affect the intragranule buffer capacity.

The effect of lysosomal storage diseases on secretory cells: an ultrastructural study of pancreas as an example

The lysosome is the disposal and recycling center of eukaryotic cells. The pancreas is an exocrine and endocrine organ. It contains different cell types secreting enzymes, hormones, ions and fluid. The purpose of this study was to demonstrate that the manifestation of the disease in individual cells depends on the expression of the defected gene within the function of the cells. We have thus compared the ultrastructural features of normal pancreas to pancreas affected by eleven different lysosomal storage diseases in human, cats, dogs and mice. The diseases studied include GM1- and GM2- gangliosidosis, galactosialidosis, alpha-mannosidosis, mucopolysaccharidosis-I (MPS-I), mucopolysaccharidosis-VI (MPS-VI), mucopolysaccharidosis-VII (MPS-VII), mucolipidosis-IV (ML-IV), Niemann-Pick C, neuronal ceroid-lipofuscinosis, and an undefined glycolipid storage disease. We demonstrated that morphological changes are seen in some pancreatic cell types but not in others, even though the genetic defect occurs in all cell types. Furthermore, we identified and characterized primary and secondary changes in affected cells. The primary changes include presence of numerous and/or enlarged secondary lysosomes laden with partially degraded substrates. The secondary changes were associated with an abnormal formation and maturation of zymogen or secretory granules. The mechanisms contributing to the secondary changes are thought to be associated with altered synthesis of various constituents of these granules.

Cytoplasmic granule formation in mouse pancreatic acinar cells. Evidence for formation of immature granules (condensing vacuoles) by aggregation and fusion of progranules of unit size, and for reductions in membrane surface area and immature granule volume during granule maturation

We used a computer-assisted morphometry approach to analyze quantitatively the process of cytoplasmic granule formation in mouse pancreatic acinar cells stimulated with pilocarpine to induce secretion. Our findings suggest that each condensing vacuole/immature granule of pancreatic acinar cells is formed by the progressive aggregation of 106 to 128 "unit progranules" of narrowly fixed volume, define a range of 7.7 to 9.2 for the factor of volume condensation between the largest immature granules and the mature unit granule, and predict that the formation of a single mature unit granule by the aggregation and fusion of unit progranules involves a net reduction of at least 95% in the amount of membrane surface area associated with these structures.

Age-related basement membrane thickening of the vocal cords in sudden infant death syndrome (SIDS)

Sudden infant death syndrome (SIDS) remains the leading cause of death in the Western world among infants between the ages of 1 month to 1 year. The diagnosis can only be established at autopsy, at which time no obvious or recognizable pathology is evident. A correlation between thickening of the basement membrane of the true vocal cords and the victim's age was observed in all 51 larynges examined, whereas no such finding was detected in 82 larynges of infants who died of other causes. Thus, the data support the authors' previous morphological results suggesting the use of basement membrane thickening as a marker of positive diagnosis of SIDS at autopsy. The possibility that an immune process may be associated with this syndrome merits further investigation and could prove to be of great importance.

Mast cell and basophil development

Mast cells and basophils express certain remarkable similarities in mediator content, histochemical characteristics, and function. Yet a large body of evidence now indicates that the mast cell and basophil lineages are distinct. Stem cell factor, the ligand for the receptor encoded by c-kit, is a major growth factor for mast cells in both rodent and primate species, and can modulate mast cell secretory function. Moreover, abnormalities affecting the stem cell factor receptor or stem cell factor might contribute to some cases of mastocytosis or mast cell neoplasms. By contrast, basophils can develop independently of stem cell factor, and are not as sensitive as mast cells to the effects of stem cell factor on mediator secretion. In addition, the cytokine interleukin-3 greatly augments the production of human basophils, but has little or no growth promoting activity for human mast cells.

Histochemical study of the blue autofluorescence of collagen in oral irritation fibroma: effects of age of patients and of the duration of lesions

The intensity of the autofluorescence of collagen was measured in 27 irritation fibromata of the buccal mucosa and 13 of the lip. The intensity of fluorescence correlated positively with the duration of the lesion. The fluorescence intensity also increased with the patients' age. The present observations show that in irritation fibromata of buccal and lip mucosae, the intensity of blue autofluorescence of the collagen increases with duration of the lesions and with the age of patients.

Histochemical characterization of collagen fibers in fibrous overgrowth (irritation fibroma) of the oral mucosa: effect of age and duration of lesion

In a study of 43 specimens of oral mucosa irritation fibroma, polarization colours of collagen thin (0.8 microm) and thick (1.6-2.4 microm) fibers were recorded in formalin-fixed and paraffin-embedded sections stained with Picrosirius red. Examination of polarization colours of both the 'thin' and 'thick' collagen fibers revealed an increase of yellowish-orange and orange fibers as a function of age in patients over 30 years old (P < 0.05 only in thick fibers). When the polarization colours of thin and thick collagen fibers were recorded as a function of duration of the lesion, there was an increase in the number of yellowish-orange and orange fibers and a decrease in blue-green and green fibers in both thin (P < 0.1) and thick (P < 0.05) populations as the lesion matured. These findings show that increments in both the patient's age and the duration of the lesions increase the amount of collagen fibers which exhibit yellowish-orange and orange polarization colours indicating tighter packing and better alignment of the microfibrils, similar to normal mature collagen. These differences may have an effect on the timing of the surgical excision.

Ultrastructure of human dermal mast cells in 29 different lysosomal storage diseases

The effect of lysosomal storage diseases on the ultrastructure of human mast cells has not previously been reported. Indeed, there has been little published evidence indicating that mast cells contain typical lysosomes. However, mast cell cytoplasmic granules contain hydrolases similar to those found in lysosomes, but which differ from lysosomal hydrolases in exhibiting optimal activity at higher pH. We therefore examined by transmission electron microscopy the dermal mast cells in 58 biopsies of patients exhibiting 1 of 29 different lysosomal storage diseases. We found mast cells containing abnormal lysosomes in 16 of these disorders. In 6 of these 16 diseases, the mast cells' cytoplasmic granules appeared normal. These observations indicate that human mast cells can contain lysosomes, and provide evidence that the enzymes affected by lysosomal storage diseases are active in mast cells.

Theoretical considerations on the formation of secretory granules in the rat pancreas

Rat pancreatic zymogen granule sizes were determined by analysis of electron micrographs of the pancreas from adult and newborn rats. Areas of granule profiles were measured and converted to equivalent volumes. Histograms of the equivalent volumes showed integral multimodal distributions which were evaluated for goodness of fit with two models, unit addition and random fusion. Previous analyses of zymogen granule size distributions have failed to recognize the multimodality we have observed. Distributions of equivalent volumes for the two models were developed using Monte Carlo simulation. In the case of the granules from the newborn rats, the distribution of granule sizes gave a better fit with the random fusion model, whereas the granules from the adult rats had distributions with a better fit to the unit granule addition model. The estimated unit granule sizes for the two different ages were the same. Both unit addition and random fusion models propose that following formation of secretory granules from Golgi-derived material, the granules fuse with one another to create a wide dispersion of granule sizes. The present results extend the evidence for fusional growth of secretory granules, originally developed for the mast cell, to the zymogen granules of pancreas. All normal cells previously studied have yielded secretory granule distributions most consistent with unit addition. The basis for the expression of random fusion in the newborn rather than the more usual unit addition is not known.

Characteristics of palatal wound healing in desalivated rats

The healing of excisional wounds in the palate of desalivated rats was evaluated. Experimental rats became desalivated after extirpation of the submandibular and sublingual glands and ligation of the parotid ducts. Small or large circular wounds, 3 or 5 mm in diameter, were produced in the palate. The wound area, area of inflammation, area of connective tissue formation and the number of myofibroblasts were determined at 0, 3, 7, 14, 21 and 28 days after surgery. The area of the small wound (3 mm) was similar in experimental and control groups; however, the area of the large wound (5 mm) was greater in the experimental group (p < 0.05-0.01). The area of inflammation was greater in the experimental group with small or large wounds (p < 0.05-0.01). Connective tissue formation was less (p < 0.01) in desalivated rats with a small wound at day 14 and with a large wound at days 21 and 28. There were fewer myofibroblasts in the large wound of desalivated rats (p < 0.01) than in controls between days 3 and 14. The results indicate that palatal wound healing is delayed in desalivated rats and that larger wounds are more sensitive to desalivation than smaller wounds.

Dissociation between release and gene expression of gonadotropin alpha-subunit in gonadotropin-releasing hormone-stimulated alpha T3-1 cell line

The alpha T3-1 cell line which was derived by targeted tumorigenesis in transgenic mice [Windle et al. (1990) Mol. Endocrinol. 4, 597-603] possesses high-affinity binding sites for GnRH analogs coupled to enhanced phosphoinositide turnover and phospholipase D activity. Incubation of alpha T3-1 cells with [D-Trp6]-GnRH analog (GnRH-A) resulted in a rapid increase in gonadotropin alpha-subunit mRNA levels which was detected already at 30 min of incubation (0.1 nM GnRH-A, 3-fold, p < 0.01). The effect diminished with time to reach basal levels at about 12 h of incubation, with a secondary rise in alpha mRNA levels between 12 and 24 h of incubation. Addition of the protein kinase C activator 12-O-tetradecanoylphorbol 13-acetate (TPA, 100 ng/mL) or the Ca2+ ionophore ionomycin (1 microM) to alpha T3-1 cells also resulted in a rapid increase in alpha-subunit mRNA levels. Surprisingly, GnRH-induced alpha-subunit release was detected only after a lag of 4 h of incubation. Thus, dissociation between exocytosis and gene expression can be demonstrated in GnRH-stimulated alpha T3-1 cell line.

The rigidity of bacterial flagellar filaments and its relation to filament polymorphism

We determined and correlated the rigidity of Salmonella typhimurium, Escherichia coli, and Rhizobium lupini flagellar filaments representing various structural and polymorphic states (plain, complex, straight, superhelical, and right- and left-handed). Persistence length, from which the filament's rigidity and other parameters (Young's modulus, bending force constant, buckling persistence length, flexural deformation, and flexural time) were derived, was determined from electron micrographs of isolated, negatively stained filaments. Outer diameters and radii of strong intersubunit connectivity were determined from three-dimensional image reconstructions and radial mass density profiles from scanning transmission electron microscopy. All filaments appear to be highly rigid with no evident correlation with their helical sense or superhelicity. The complex filament of R. lupini is rigid to the extent that it becomes brittle. The overall flexibility of the flagellum seems to stem mainly from the hook and not from the filament. Polymorphism is probably related to the propelling properties and hydrodynamic shape of the filament rather than to its rigidity.

Morphometric studies of pancreatic acinar granule formation in NCTR-Balb/c mice

NCTR-Balb/c mice are afflicted with a cholesterol lysosomal storage disorder stemming from a defect in intracellular cholesterol processing. The clinical and biochemical abnormalities expressed in the mice resemble Niemann-Pick type C and D disorders in humans. One of the proposed mechanisms to explain the pathophysiology of the disorder implies a defect in the process of membrane transport that normally takes place in the vesicular movement of cholesterol to specific target sites in the cell. Secretory granule formation in pancreatic acinar cells is one of the biological processes known to involve massive membrane flow. Thus, we have undertaken a morphometric study of the regranulation mechanism in the pancreatic acinar cells of the mutant mice, as a way of studying cellular membrane movement. Electron micrographs of pancreatic acinar cells from mutant and normal mice were taken at several time points after extensive degranulation induced by pilocarpine injection. Two hours after stimulation the pancreatic cells demonstrated a complete loss of granules, and at later time points newly formed granules appeared. Identical unit granule volumes were observed in both groups, indicating that the progranules were of normal size. However, the rate of granule formation and maturation was reduced in the mutant mice, which might be the result of a defect in membrane function.

Unusual renal deposit in mixed connective tissue disease

We describe a patient with clinical signs of mixed connective tissue disease who developed nephrotic syndrome. The kidney biopsy revealed glomerular and vascular deposits that stained positive with Congo red and showed a green birefringence. The Congo red positivity became negative in sections treated with potassium permanganate. Peroxidase-antiperoxidase staining with anti-AA antibodies was strongly positive. Ultrastructurally, although the deposits were similar to amyloid, they were about twice the size of amyloid fibrils. To our knowledge, the deposition of an amyloidlike material that shows the histochemical and immunohistochemical features of amyloid AA but is lacking the distinctive ultrastructural characteristics of amyloid fibrils has not been described.

Histopathology of benign prostatic hyperplasia after failure of hyperthermia treatment

We have used a fine morphometric method to evaluate hyperplastic prostate tissue after treatment by local hyperthermia and compare it with untreated specimens. Local hyperthermia was delivered to the prostate gland by a transrectal applicator using microwaves at 915 MHz. Prostatic tissue was obtained from 13 patients who had completed a course of local hyperthermia treatment and who underwent prostatectomy 3 to 12 months later because the treatment had failed. Prostatic tissue from 9 patients who had undergone prostatectomy with no previous treatment served as a control. A significant reduction in the volume fraction of fibrous tissue was found in the study group (37%) compared with the general population (48%). No inter-group difference was observed in the volume fractions of vascular or glandular tissue. We suggest that the difference observed in the fibrous elements may be the reason for the failure of treatment and that the histological composition of the diseased gland may, therefore, be a key factor in determining the outcome.

Mast cells in rat dermis and jejunal lamina propria show a five-fold difference in unit granule volume

The cytoplasmic granules of mast cells have a periodic multimodal size distribution in which the volumes of individual granules are integral multiples of the intermodal distance, a volume defined as the "unit granule" or v1. In this study, we used two 3-month-old male rats to analyze two classical mast cell subpopulations, dermal "connective tissue-type mast cells" and jejunal lamina propria "mucosal mast cells", for the morphometric characteristics of their cytoplasmic granules. Both v1 and the mean volume of individual cytoplasmic granules were much smaller in dermal than in jejunal mast cells (ratios of 1:5.5 and 1:4.2, respectively), but dermal mast cells contained 150% more granules per cell than did jejunal mast cells. The two types of mast cells did not differ significantly in total cell volume, nucleus volume, aggregate volume of cytoplasmic granules per cell or numbers of unit granules comprising a granule of mean volume. These findings add unit granule volume to the list of phenotypic characteristics which express significant variation in anatomically distinct populations of mast cells.

Extraction wound healing in desalivated rats

Wound licking has been shown to promote extraoral wound healing among animals. Although the oral mucosa is bathed in saliva. Little information about the role of saliva in oral wound healing is found. The present study evaluates the healing of extraction wounds in desalivated rats. Experimental rats underwent sialadenectomy of the submandibular and sublingual glands and ligation of the parotid ducts. Maxillary left first molars were extracted. Rats were killed at 0, 1, 3, 5, 7, 10, 14, and 21 days after surgery and maxillae were prepared for light microscopy examination. Generally, a delay in socket healing in the desalivated rats was found. No differences were observed in blood clot formation. Replacement of the clot by granulation tissue was relatively slow concomitant with a longer inflammatory process. Bone formation kinetics were slower among the experimental rats.

Osteopenia, hematopoiesis, and bone remodelling in iliac crest and femoral biopsies: a prospective study of 102 cases of femoral neck fractures

Cancellous microanatomy, bone remodelling, and hematopoietic tissue were studied in iliac crest and femoral neck biopsies taken intraoperatively in 102 consecutive patients with displaced intracapsular fractures. About half of the femoral biopsies had osteopenia, and most showed replacement of hematopoietic tissue by fat cells, with absence of osteoblasts and osteoclasts. In contrast, most of the iliac crest biopsies showed relatively less decrease in cancellous bone, while hematopoietic tissue and bone remodelling cells were present in approximately 75%. These results indicate that the iliac crest biopsy does not necessarily reflect cancellous microanatomy, hematopoietic tissue, and bone remodelling at other skeletal sites in any given patient.

Lipid pigment (lipofuscin) accumulation in rat tongue muscle with aging

Lipid pigment (lipofuscin) was examined in perioral and tongue muscles of aging rats. While in perioral striated muscle the pigmented granules could not be found, a considerable accumulation with aging could be noted in the tongue muscle. Unlike the human tongue muscle, in which the pigmented granules were stored in clusters of different sizes at the nuclear poles of the muscle fibers, in rats, they were scattered randomly through the cytoplasm. The results of this study suggest that lipofuscin can be used as a marker for aging of the tongue muscle in the rat.

Morphological evidence for chronic mast cell activation after prolonged exposure with supernatants from chronic graft-versus-host splenocytes

Chronic graft-vs.-host disease (cGVHD) includes a syndrome of inflammatory and fibrotic changes in some respects resembling scleroderma. In the present study we have quantitated the number of peritoneal mast cells (MC) in mice with cGVHD induced across minor histocompatibility barriers. MC were evaluated by staining with toluidine blue. The number of MC decreased significantly (by 25%) at the onset of the cGVHD fibrosis (day 12). Around day 35, MC were virtually undetectable, and started to reappear on day 130. Upon clinical recovery (day 200) a dramatic increase in MC numbers was found (about 8-fold). In addition, we evaluated by electron microscopy the morphology of peritoneal MC, obtained from normal mice and rats, that had been co-cultured on 3T3 fibroblast monolayer in the presence of splenocyte supernatants from mice with cGVHD or from control mice. After 6-8 days of continuous incubation with the cGVHD splenocyte supernatant, MC appeared to be activated, since they displayed an array of heterogenous granules. Few of the granules were dense; many were swollen and pale. Rare granule extrusion was evident. This would indicate that MC underwent a slow activation process due to a factor(s) present in the cGVHD supernatant, different from the classical acute anaphylactic activation.

Morphometric analysis of gold particles in low-label cell compartments

Quantitative estimation of the binding of gold-conjugated ligands to various cell organelles has become a commonly used method to quantify the amount of ligand-binding sites associated with those organelles. However, often a small percentage of organelles is labeled or the density of gold labeling is low. We have defined the "gold-labeled region" as a zone that has a boundary defined by the localization of the outermost gold particles. Such a phenomenon was recently observed in a study of the internalization of gold-labeled native surfactant into lamellar bodies of cultured pulmonary type II cells. We estimated the size and density of gold-labeled regions in lamelar bodies using a simple stereological approach and demonstrated that the low percentage of gold-labeled organelles can be explained as a result of the probability of random selecting through the labeled areas. Our method, which permits use of transmission electron microscopy to calculate the true parameters of gold-labeled regions, can significantly facilitate analyses of ligand binding to various cell compartments.

Cutaneous responses to histamine, compound 48/80 and codeine in patients with hyperthyroidism

The regulatory effects of various endocrine factors on allergic processes have been widely studied. The clinical importance of hyperthyroidism in asthma and in chronic urticaria has been demonstrated in several cases. These observations may be attributed to modulatory effects of thyroid hormones on mast cell releasability and/or on other target organs as blood vessels. To evaluate the effects of thyroid hormones on mast cell releasability and on the cutaneous vasculature, we analyzed the wheal and flare response to compound 48/80, to codeine, and to histamine in patients with hyperthyroidism and in a control group. No significant difference was found between the two groups. We could not demonstrate any in vivo effect of the thyrotoxic state on the cutaneous response to these substances.

Morphometric evaluation of benign prostatic hyperplasia

Resected prostate tissue from 9 patients with benign prostatic hyperplasia was subjected to a morphometric analysis. The relative volume density of 4 prostatic tissue components was determined: fibrous (47%), muscular (8%), vascular (3%), and glandular (18%). The resolution of the stromal portion of the hyperplastic prostate into 3 subcomponents represents a finer level of resolution than that previously reported. This enhanced precision in the determination of tissue composition lends new insight into the etiology of benign prostatic hyperplasia, and provides a basis for the evaluation of novel approaches to its treatment.

Mast cell activation by hornet (Vespa orientalis) venom

As far as its effect on the activation of rat peritoneal mast cells is concerned, the venom of young hornets (age 0-24 h) differs from that of adult hornets (over 24 h of age). 'Juvenile' venom caused activation mainly in rats previously sensitized to it, whereas 'adult' venom induced activation regardless of presensitization. Furthermore high concentrations of 'adult' venom were cytotoxic to the entire murine peritoneal cell population, but 'juvenile' venom was not toxic. SDS-PAGE data demonstrate that the venom of young hornets contains a unique component (82 kD), nonexistent in adult venom. Our data demonstrate that hornet venom activity is correlated with the hornet's age.

Ontogeny of mast cells in the ventral prostate of the rat

The ontogenic evolution of mast cells in the rat ventral prostate was studied using the Grimelius silver impregnation method. The mast cell density was highest during the pubertal period and later, it declined significantly with age. Most mast cells were identified in the fibrovascular stroma in close proximity to nerve fibers and blood vessels. The total number of mast cells seems to be constant when correlated with prostatic weight.

Recovery of rat mast cells after secretion: a morphometric study

Granule reconstitution in rat peritoneal mast cells following massive secretion was studied by morphometric techniques. Immediately following secretion, the earliest identifiable mast cells showed a substantial decrease in cell volume associated with granule loss. Cell volume then increased almost to the original level over a period of a month. The size of the Golgi apparatus increased markedly in the week following secretion and then returned to its original size. The total volume of granules increased slowly after the secretory depletion and by 34 days had not returned to the original value although the number of granules had recovered fully. The reconstitution of mast cells after secretion is a prolonged process with several phases resulting in mast cells of varying appearance and content. This heterogeneity generated by reconstitution post secretion must be considered in studies of populations of mast cells in vivo.