PubMed Health⌕ Search

Biomedical subjects

S Cinti

Publications and source records attributed to S Cinti.

At least 19 recordsLinked to original sources
PubMed1995

Ultrastructure of human parathyroid cells in health and disease.

Parathyroid glands (n = 271) removed from 130 patients were examined by light and electron microscopy. A standardized method of tissue processing was employed and morphometry was performed. The aim of the paper is to provide a description of the human parathyroid chief cell ultrastructure in health and disease, with quantitative evaluation of structures involved in secretion of parathyroid hormone in a large case series, and to discuss their role in current diagnostic histopathology. The patients were euparathyroid (n = 10), or affected by primary (n = 97), secondary (n = 8), or tertiary (n = 15) hyperparathyroidism. In normal glands, solid parenchyma was composed of chief cells, large clear cells, transitional-oxyphil cells, and oxyphil cells. Chief cell hyperplasia, pseudo-adenomatous hyperplasia, adenoma, water-clear cell hyperplasia, and carcinoma were the most usual forms of parathyroid disease responsible for primary hyperparathyroidism. In chief cell hyperplasia, all the parathyroid glands were enlarged and the chief cells were in an active state of hormone secretion, with a large Golgi complex, abundant rough endoplasmic reticulum (RER), small lipid droplets, and tortuous plasma membrane. In pseudo-adenomatous hyperplasia, one gland was enlarged and the others displayed a normal size; however, electron microscopic examination and morphometric analysis showed that all the glands had active cells. Adenomas displayed a pattern similar to those of pseudo-adenomatous hyperplasia, with one gland enlarged and the others of normal size. However, ultrastructural examination and morphometry showed that the normal-size glands were hypo-active. Water-clear cell hyperplasia showed cells filled with cytoplasmic vacuoles. In these cells, structures with intermediate features between secretory granules and vacuoles were visible. Nucleo-cytoplasmic atypias were frequently visible in parathyroid carcinoma cells. In secondary and tertiary hyperplasia, active chief cells were regularly mixed with oxyphil or transitional-oxyphil cells. The tertiary hyperplasia was characterized by RER-associated structures that were not found in the normal or other pathological conditions. These results demonstrate that electron microscopy and morphometry represent useful tools in parathyroid histopathology.

Adult↗
PubMed1995

Immunohistochemical, ultrastructural and morphometric evidence for brown adipose tissue recruitment due to cold acclimation in old rats.

OBJECTIVE: The aim of this work was to study the reactivity to chronic cold stress of interscapular brown adipose tissue (IBAT) in old rats by stereological, immunohistochemical and ultrastructural methods. DESIGN: Five 2-year-old rats were cold-acclimated at 4 degrees C for 4 weeks and six rats were used as controls (20-23 degrees C). MEASUREMENTS: The following were measured: IBAT volume and weight; unilocular and multilocular brown adipocyte content; preadipocyte number; multilocular cell mitochondrial area; cristae length and density per mitochondrion, and immunoreactivity for the brown adipose tissue specific uncoupling protein (UCP). RESULTS: Following cold acclimation, IBAT increased significantly in weight, volume, relative mass and number of multilocular adipocytes (170%). The number of unilocular adipocytes did not vary significantly. Multilocular adipocytes of both cold-acclimated rats and controls expressed the uncoupling protein, but in the experimental group cristae length and density per mitochondrion were significantly higher. Multilocular adipocyte precursors were observed in only one cold-acclimated rat but not in controls. CONCLUSION: The response of brown adipose tissue of old rats to chronic cold stimulus is similar to that observed in young and adult rats. Cold acclimation induces brown adipocyte recruitment: their number increases significantly, they test UCP-positive and their mitochondria are significantly more active than in controls. On the other hand, the number of unilocular adipocytes is not significantly affected, which may serve to improve the utilization of the heat produced by thermogenesis.

Acclimatization↗
PubMed1995

Subcutaneous nodules in a patient hyposensitized with aluminium-containing allergen extracts: a microanalytical study.

Electron spectroscopic imaging (ESI) is a recent tool for electron microscopic analysis which permits the recognition of the distribution of elements in a specimen, with a spatial resolution up to 5 nm. The authors performed the ESI together with X-ray microanalysis (EDX) and transmission electron microscopy to study granulomatous subcutaneous nodules in a patient who had undergone a desensitising therapy with an aluminium-containing vaccine. Aluminium was detected both by EDX and ESI, mainly in lysosomes of histiocytes containing needle-shaped material in a lucent matrix. However, ESI provided a better localization of aluminium with respect to EDX. This result suggests that the identification of aluminium-containing structures cannot be obtained only by ultrastructural morphology and underlines the utility of a microanalitycal study for a correct diagnosis in the presence of a needle-shaped deposition of dense material in lysosomes.

Aluminum↗
PubMed1994

Skin abnormalities and autonomic involvement in the early stage of amyotrophic lateral sclerosis.

With the aim to evaluate skin abnormalities in patients affected by amyotrophic lateral sclerosis (ALS) with respect to the dermal ultrastructure, including autonomic termination, microcirculation and sweat glands, 13 ALS patients and 5 controls underwent a skin biopsy of the left forearm. Abnormalities of the collagen and elastic fibrils were found in 4 and 5 patients respectively; amyelinic axons and sweat glands showed ultrastructural abnormalities in most ALS patients but not in controls; a quantitative evaluation of the collagen fibrils showed greater diameter of fibrils, larger interfibrillar spaces and more consistent size variation in ALS patients than in controls. These results suggest autonomic involvement in ALS and changes in the collagen fibril organization during the early stages of the disease.

Aged↗
PubMed1994

Immunohistochemical identification of the uncoupling protein in human hibernoma.

The expression of the uncoupling protein (UCP), a protein unique to brown adipocyte mitochondria, was studied in sections of a human hibernoma by means of immunohistochemistry. Multilocular, but not unilocular, adipocytes expressed the UCP in the tissue. Further, the immunostaining was not uniform in multilocular cells, because small adipocytes with finely multivacuolar or scanty lipid deposit showed more intense staining. This pattern is similar to that found in brown adipose tissue. Ultrastructural investigation confirmed that a majority of proliferating cells had the morphological characteristics of brown adipocyte. Results indicate that adipocytes in hibernoma may be very close to brown adipocytes both morphologically and immunocytochemically.

Adipocytes↗
PubMed1994

Electron spectroscopic imaging of secretory granules in human eccrine sweat glands.

A study of human eccrine sweat glands by electron spectroscopic imaging has been performed. A high nitrogen content in secretory granules of the dark mucous cells has been found while mucous cells in the digestive or respiratory systems did not contain nitrogen detectable in our experimental conditions. High concentrations of nitrogen were found in zymogenic granules and in the core of the granules in the eosinophilic leucocytes. Our findings seem to suggest that the granules of the dark secretory cells are composed not only of mucoid substances but contain also high concentrations of proteins. The descriptive term "granulated cells" seems to be more correct than "mucous cells" to indicate these elements.

Adult↗
PubMed1993

S-100 protein in rat brown adipose tissue under different functional conditions: a morphological, immunocytochemical, and immunochemical study.

The brown adipose tissue (BAT) is responsible for nonshivering thermogenesis, exhibiting changes in cell morphology related to the functional conditions. In stimulated BAT (neonatal period, cold acclimation) the large majority of adipocytes become multilocular and active, while in inactive BAT (warm acclimation) most cells are pauci- or unilocular and inactive, very similar to white adipocytes. It is well known that white adipocytes are sites of concentration of S-100, a calcium-binding protein originally isolated from the nervous system and later detected also in nonneural cell types, whereas data on the possible presence of this protein in BAT are lacking. The present study used morphological, immunocytochemical, and immunochemical methods to investigate the presence of S-100 protein in BAT under different functional conditions. We found that S-100 was present in both stimulated and inactive BAT and that is was expressed in significantly higher quantities in the latter than in the former. The multilocular cells were always negative (in both active and inactive tissue), whereas the pauci- and unilocular cells were always S-100-positive under both functional conditions. These data suggest that only pauci- and unilocular brown adipocytes express S-100 protein, thus manifesting a possible relationship between S-100 and cell morphology.

Adipose Tissue, Brown↗
PubMed1993

The normal, cryptorchid and retractile prepuberal human testis: a comparative morphometric ultrastructural study of 101 cases.

Fifty-two surgical biopsies from retractile testes of patients in pediatric age (3-14 years), of which 25 were treated with hormonal therapy (RT) and 27 did not undergo therapy before orchidopexy (RNT), were compared with the biopsies of 18 normal (N) and 30 cryptorchid or ectopic (E) testes. A light and electron microscopic morphologic and morphometric study was performed. For the quantitative investigation 4 parameters were selected: a) the mean tubular diameter (on 20 cross-sections); b) the mean spermatogonial number per tubular section; c) the mean nucleolar area of the Sertoli cells; and d) the mean thickness of the tubular basal lamina. The 101 biopsies were collected for statistical evaluation into four age groups: 3-6 years, 7-10, 11-13 without spermatogenesis and 10-14 with signs of early spermatogenesis. In the RT category the mean tubular diameter and the mean spermatogonial number were similar to N in the first two age groups, but were significantly reduced in the RNT categories. The morphometric study of the Sertoli cell nucleolar area confirms the delay of maturation observed in the categories of RT, RNT and E. In normal biopsies, the basal lamina shows a progressive reduction of the thickness, with the lowest values around puberty, while constantly higher values were found in the other categories, although this increase is not statistically significant.

Adolescent↗
PubMed1992

Ultrastructural modifications in one case of hairy cell leukemia during alpha-interferon therapy.

There are many reports concerning the morphology of hairy cell leukemia (HCL), but, to our knowledge, there are no data on the ultrastructural modifications of HCL during interferon therapy. The ultrastructural modifications of neoplastic cells in peripheral blood in a case of HCL were investigated before and 2 and 4 months after beginning treatment with human lymphoblastoid alpha-interferon. Before therapy, hairy cells displayed the typical cytoplasmic projections, and 4% contained ribosome-lamellae complexes (RLC) (the cells contained up to 7 RLC). Two months from the beginning of therapy, hairy cells had shorter projections, RLC had disappeared, and tubuloreticular structures (TRS) had appeared in 2.2% of the elements. Four months from the beginning of therapy, TRS persisted in 2.3% of hairy cells, cylindrical confronting cisternae (CCC) appeared in 6.8% of the cells, and uncommon RLC, in close contact with the rough endoplasmic reticulum and nuclear membrane, were found in 1.5% of the elements. The cells contained up to 3 RLC. Our data confirm that interferon stimulates the synthesis of TRS and CCC, whereas the reappearance of uncommon forms of RLC could reflect their neosynthesis, possibly related to the interferon therapy. The frequent findings of a close contact between RLC and nuclear membrane support the view that RLC are derived not only from rough endoplasmic reticulum, but also from the nuclear membrane.

Adult↗
PubMed1992

Parathyroid glands in primary hyperparathyroidism: an ultrastructural morphometric study of 25 cases.

In parathyroid glands removed from patients with primary hyperparathyroidism (pHPT), hyperplasias and adenomas cannot be distinguished from one another by light microscopy when only one gland is available for examination. When a second gland is available, it is necessary to establish whether it is normal, suppressed, or hyperplastic. This distinction may be difficult, and the main criterion is the amount of cytoplasmic lipid in the parenchymal cells. If the lipid is abundant, the gland is considered normal or suppressed, and if it is scanty, the gland is interpreted as hyperplastic. We have performed a morphometric ultrastructural study to test the reliability of this criterion. Twenty-five adenomatous glands removed from patients with pHPT, when compared with glands of normal size from euparathyroid patients, showed a significant increase in the parameters indicative of metabolic activity, namely the size of the Golgi apparatus, the amount of rough endoplasmic reticulum, and the length of plasmalemmas. In addition, the amount of cytoplasmic lipid was significantly reduced. Furthermore, 25 glands of normal size removed from the same patients with pHPT showed an amount of lipid similar to that of normal glands from euparathyroid patients. However, all the parameters indicative of metabolic activity were significantly higher than those in glands from euparathyroid patients and comparable to those found in adenomatous glands. These results suggest that in pHPT, normal-size glands are as active as adenomatous glands, regardless of a higher lipid content.

Adenoma↗
PubMed1992

Steatosis associated with immotile cilia syndrome: an unrecognized relationship?

The present study deals with a case of hepatic parenchymal steatosis in a child with primary ciliary dyskinesia (immotile cilia syndrome) well documented by functional and ultrastructural evaluation of the ciliary epithelia. Hepatic steatosis was associated with ultrastructural evidence of retention of material either in the cisternae of the endoplasmic reticulum or in proximity of the Golgi apparatus of hepatocytes. It is suggested that the absence of dynein in the axoneme is probably part of a diffuse genetic defect which may extend to cytoplasmic, non axonemal, dynein and lead to a disturbance of various microtubule-dependent cell activities.

Biopsy, Needle↗
PubMed1992

Occurrence of brown adipocytes in rat white adipose tissue: molecular and morphological characterization.

Brown adipocytes are thermogenic cells which play an important role in energy balance. Their thermogenic activity is due to the presence of a mitochondrial uncoupling protein (UCP). Until recently, it was admitted that in rodents brown adipocytes were mainly located in classical brown adipose tissue (BAT). In the present study, we have investigated the presence of UCP protein or mRNA in white adipose tissue (WAT) of rats. Using polymerase chain reaction or Northern blot hybridization, UCP mRNA was detected in mesenteric, epidydimal, retroperitoneal, inguinal and particularly in periovarian adipose depots. The uncoupling protein was detected by Western blotting in mitochondria from periovarian adipose tissue. When rats were submitted to cold or to treatment with a beta-adrenoceptor agonist, UCP expression was increased in this tissue as in typical brown fat. Moreover, the expression was decreased in obese fa/fa rats compared to lean controls. Morphological studies showed that periovarian adipose tissue of rats kept at 24 degrees C contained cells with numerous typical BAT mitochondria with or without multilocular lipid droplets. Immunocytochemistry confirmed that multilocular cells expressed mitochondrial UCP. Furthermore, the number of brown adipocytes and the density of mitochondrial cristae increased in parallel with exposure to cold. These results demonstrate that adipocytes expressing UCP are present in adipose deposits considered as white fat. They suggest the existence of a continuum in rodents between BAT and WAT, and a great plasticity between adipose tissue phenotypes. The physiological importance of brown adipocytes in WAT and the regulation of UCP expression remain open questions.

Adipose Tissue↗
PubMed1992

[Peripheral neuropathy associated with Castleman's lymphoma].

Castleman's lymphoma is a rare clinicopathological entity and is often difficult to classify nosographically. From the histopathological point of view two variants are recognized, one hyalino-vascular and one plasma cellular. Moreover Castleman's lymphoma may be multifocal or unifocal (located within the thorax in 70% of patients). The plasma cellular variant is often associated with systemic symptoms such as fever, sweating, organomegaly, polyneuropathy, and mono- or polyclonal gammopathy. We describe a rare case of unifocal, plasma cellular-type Castleman's lymphoma located in the mediastinum, asymptomatic at onset but later dominated by neurological symptoms (chronic isolated polyneuropathy whose clinical expression was predominantly motor). A brief review is presented of the main clinico-histological characteristics of Castleman's lymphoma together with some hypotheses about the pathogenesis of the associated neuropathy.

Adult↗
PubMed1991

Structural and functional modifications induced by ketamine on synaptosomes in the rat.

This study correlates previous observations on the effects of a general anaesthetic (2-chlorophenyl-2-methylaminocyclohexanone, trade name Ketalar), administered in vivo on the functional properties of synaptosomes from the brain of the rat, with structural modifications detected using freeze-fracture electron microscopy. The anaesthetized rats exhibited a fluidization of the synaptic membranes, as probed by stearic acid spin labels, accompanied by a decrease in the activity of acetylcholinesterase. The freeze-fracture images of synaptosomes from anaesthetized rats showed a clear statistical increase in the number of vesicles with aggregated intramembrane particles, without any significant change of the particle diameter. The hypothesis that a perturbation of the lipid protein interaction is a primary effect, in the mechanism of action of anaesthetics, is supported at present only by indirect evidence.

Acetylcholinesterase↗
PubMed1991

Rat interscapular brown adipose tissue at different ages: a morphometric study.

Interscapular brown adipose tissue (IBAT) was studied in newborn and 1, 3, 5, 7, 13, 26, 52, 78 and 104-week-old rats maintained under standard laboratory conditions in order to define its morphological modifications and assess previous statements on an involution phase of IBAT after the first weeks of extrauterine life. Serial sections were analysed morphometrically to quantify the multilocular, the monolocular and the connective-vascular components of IBAT. Morphometry shows that the IBAT weight and volume progressively increase up to the twenty-sixth week of age, these figures remaining almost constant thereafter. The volume of the unilocular and connective components increased with age. The volume of the multilocular component increases up to the sixth month of age, and slightly reduces thereafter. The number of the multilocular adipocytes is almost constant from the third week up to the second year of life. Our results suggest that, in IBAT of adult animals, despite a slight prevalence of unilocular adipocytes, the number of multilocular cells is not reduced with respect to younger animals.

Adipose Tissue↗
PubMed1991

The correlation between magnetic resonance imaging and ultrastructural patterns of brown adipose tissue.

The present paper reports on magnetic resonance imaging (MRI) at high spatial resolution of the brown adipose tissue (BAT) in laboratory rodents, in comparison with light and electron microscopy findings. Our aim was to assess whether MRI correlates with the expected ultrastructural differences between newborn and adult BAT. The study was performed on the cervical and the interscapular BAT deposits by means of a nuclear magnetic resonance (NMR)-spectrometer equipped with a high resolution imaging system. Ultrastructural examination of BAT at different ages showed three different patterns of adipocyte ultrastructure in BAT which were associated with different MRI patterns. In BAT, MRI identifies the prevalent type of adipocyte in the tissue providing information consistent with ultrastructural results. Results presented here show that MRI represents a precise and reliable tool to investigate the morphology of tissues in living animals. The safe, non-invasive MRI technique represents a very useful tool in morphological research.

Adipose Tissue, Brown↗
PubMed1990

Morphometric evaluation of intracytoplasmic lipid in normal and pathological parathyroid glands.

The chief morphological criterion for classifying parathyroid glands as 'normal', 'suppressed', or 'activated' is the lipid content of the cytoplasm. In particular, cytoplasm lipid deposit is scanty in the active parathyroid cell, according to many authors. In this paper we present the results of a morphometrical study of ten normal parathyroid glands from patients undergoing thyroidectomy, 20 enlarged 'adenomatous' glands from patients with primary hyperparathyroidism, and 20 glands of normal size from the same hyperparathyroid patients. We aimed at assessing the content of intracytoplasmic lipid of secretory cells in all these conditions. The results show that secretory cells of adenomatous glands have less lipid than those from normal glands; however, there was considerable overlapping of the data in the two groups. The mean lipid content of cells in glands of normal size taken from hyperparathyroid patients was not significantly different from the mean value of normal cells, even when ultrastructural evidence of activation was present in the former. These data suggest that caution has to be exercised in assessing the functional status of parathyroid glands on the basis of lipid content of secretory cells, mainly when differentiating between adenoma and hyperplasia.

Cytoplasm↗