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C Tomasini

Publications and source records attributed to C Tomasini.

At least 37 records · Page 2Linked to original sources
PubMed1997

Dermoid cyst of the penis.

A dermoid cyst of the penis has not been documented previously in the literature. We report a young Caucasian who had an important swelling of the penis dating back several months. On examination a subcutaneous mass on the dorsal aspect of the shaft and prepuce was present. A cutaneous sinus discharging purulent material was also noted above the mass. Laboratory tests including serology for syphilis and bacteriologic examination were negative. An excisional biopsy revealed a nodular lesion in the subcutaneous tissue with tufts of hair emerging from the surface. Histopathologic examination disclosed granulation tissue containing fragments of hair surrounded by granulomatous infiltrate. Serial sections allowed identification of a subcutaneous cyst. The wall was epidermoid and connected with several pilosebaceous units. A sinus tract lined by stratified squamous epithelium contiguous with the epidermis was also noted. Clinical and histopathologic differential diagnoses are discussed. Evidence for a congenital origin of this condition is given.

Adult↗
PubMed1996

Recurrent necroinflammatory disease of multiple organs and colon. Systemic presentation of inflammatory bowel disease or gut involvement during systemic disorder.

A 30-year-old man with a recurrent febrile illness resembling infection is described. Because he presented with an acute abdomen, he underwent a laparotomy, which showed the paraaortic and mesenteric lymph nodes to be changed into an abscess-like granulomatous tissue made up of necrotized granulocytes. During further flare-ups, the disease affected the spleen, skin, colon, peripheral nerve, and muscle. Histology on the biopsy materials of both the skin and colon, and on the surgically removed spleen showed the same invading pathologic tissue. Exhaustive investigation disclosed no pathogen, and the flare-ups responded repeatedly to high-dose steroids. This patient's picture has recently been defined as a syndrome of chronic granulomatosis based on several published cases. As a distinctive feature, in our patient the granulomas affected also the colon. For the present, and for another previously described similar case we analyzed the factors that might permit the differential diagnosis between the above-mentioned granulomatous syndrome and Crohn's colitis.

Adult↗
PubMed1996

Folliculosebaceous cystic hamartoma with perifollicular mucinosis.

An 8-year-old boy had a congenital, solitary verrucous lesion on his ear that histologically showed numerous maloriented infundibulocystic structures from which radiated immature sebaceous lobules as well as hair germs with rudimentary papillae. The surrounding stroma was fibrillary, containing large quantities of mucin. We conclude that perifollicular mucinosis, considered to be specific to Carney's syndrome, can also be observed in solitary folliculosebaceous hamartoma.

Child↗
PubMed1996

Cellular neurothekeoma.

We describe the histological and immunohistochemical findings of two cases of cellular neurothekeoma, a recently recognized benign neoplasm considered to be of neural origin. Morphologically they were characterized by a dermal proliferation of plexiform fascicles and small nests of pale eosinophilic, epithelioid or spindle-shaped cells which ramified in an ill-defined pattern between collagen bundles. Scant to moderate amounts of mucin were detected only in the plexiform lobules. Purely myxoid and cellular lobules concurred in these neoplasms. Immunohistochemically, both neoplasms exhibited focal immunoreactivity of the cells for factor XIIIa, providing further evidence for perineural differentiation. Problems of differential diagnosis with other plexiform neoplasms of uncertain origin are discussed.

Adult↗
PubMed1995

Agminated Spitz nevi occurring within a congenital speckled lentiginous nevus.

A 40-year-old woman had a speckled lentiginous nevus on her thigh since birth. During her first pregnancy, additional papules and nodules appeared within the preexisting hyperpigmented area, histologic examination of which showed features of both junctional and compound Spitz's nevi accompanied by simple lentigolike changes. In this particular case, speckled lentiginous nevus may have constituted a particular environment for the production of multiple Spitz nevi.

Adult↗
PubMed1995

Recurrent Sweet's syndrome in reactivated Crohn's disease.

A 50-year-old woman developed an acute febrile dermatosis on two occasions concurrently with recurrent Crohn's disease of the colon. Based on the presence of painful erythematous plaques on both hands and forearms, on the leukocytosis with excess bands in peripheral blood, on the histology showing dermal infiltration by mature granulocytes, and on the prompt response to steroids, the diagnosis was made of Sweet's syndrome associated with Crohn's disease. Sweet's syndrome is thought to be a hypersensitivity reaction that leads to parainflammatory (e.g., infections, autoimmune disorders, vaccinations) and paraneoplastic (myeloproliferative disorders, solid malignancy) associations, with a frequency of 10-30%. The association of Sweet's syndrome with Crohn's disease is very rare, but the gastroenterologist should readily differentiate it; it is important to be aware that such patients may have a nonspecific elevated activity index owing to the underlying dermatosis.

Biopsy↗
PubMed1994

Fluorimetric determination of electrically evoked increase in intracellular calcium in cultured cerebellar granule cells.

A technique is described to measure the electrically evoked increase in intracellular calcium in cerebellar granule cells cultured on glass coverslips and preloaded with FURA-2. To minimize light scattering, the coverslip containing the granules was placed in the fluorimeter cuvette at a 30 degrees angle to the exciting light beam. The cuvette was provided with 2 platinum electrodes so as to stimulate the neurons with a tangential field. The [Ca2+]i transients were maximized by omitting Mg2+. The fluorescence peaks were directly related to the pulse (1 ms, 100 mA) frequency and to the train length. The responses were completely tetrodotoxin- and [Ca2+]o-dependent and could be replicated 5-6 times at 5-min intervals. At the stimulation rate of 20 Hz for 5 s, a condition ensuring submaximal peaks, the [Ca2+]i rose from the basal levels of 41 +/- 2.7 nmol/l to 89.6 +/- 5.8 nmol/l. The participation of various membrane channels in the electrically induced [Ca2+]i increase was demonstrated. 4-Aminopyridine (1 mM) increased the height of the peaks to 240%. Both nifedipine (10 microM) and omega-conotoxin (1 microM) reduced the transients by about 25%. The residual response (in the absence of Mg2+) depended mostly on the release of endogenous glutamate as it proved sensitive to NMDA, AMPA and t-ACPD receptor antagonists. Since a technique to measure the electrically evoked release of D-[3H]aspartate is presently available, the parallel determination of release and of [Ca2+]i in twin populations of cultured granule cells is possible.

Animals↗
PubMed1994

Excitatory amino acids (EAAs) stimulate phosphatidylinositol turnover in adult rat striatal slices: interaction between NMDA and EAA metabotropic receptors.

The effect of excitatory amino acids (EAAs) on phosphatidylinositol (PI) turnover in adult rat striatal slices was investigated. Quisqualic acid (QA), alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), kainic acid (KA), ibotenic acid (IBO) and N-methyl-D-aspartic acid (NMDA) maximally increased inositol phosphate (IP) formation at 10 microM while trans-1-amino-cyclopentane-1,3-dicarboxylic acid (ACPD) was maximally effective at 100 microM. The NMDA channel blocker dizolcipine (MK-801) counteracted the effect of NMDA 10 microM and IBO 10 microM while it potentiated that of IBO 100 microM and IBO 1000 microM. Conversely, the non-NMDA receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) prevented the effect of AMPA and KA and reduced that of QA (all at 10 microM). Lowering extracellular Ca2+ concentrations ([Ca2+]0) differentially affected the PI response to EAAs. The ACPD 30 microM effect was unchanged at low [Ca2+]0 (but abolished when EGTA 2 mM was added), while that of ACPD 100 microM was halved in 0.1 mM and almost abolished in a nominally free Ca2+ medium. NMDA 10 microM and AMPA 10 microM were ineffective at low [Ca2+]0 while NMDA 100 microM, ineffective in a 1.2 mM Ca2+ medium, strongly stimulated IP formation in 0.1 mM Ca2+ but not in a nominally free Ca2+ medium. The effect of NMDA on EAA metabotropic receptor agonist stimulated PI turnover was also studied. NMDA 10 microM potentiated the effect of ACPD 30 microM. This positive cooperation persisted at low [Ca2+]0 but not in the presence of EGTA. Conversely, NMDA 100 microM prevented the effect of ACPD 100 microM. This negative interference was reversed when Ca2+ was omitted from the medium. This study shows that in the adult rat striatum both EAA metabotropic and ionotropic receptor activation increases IP formation. A positive and negative interaction between NMDA and metabotropic receptor activation was also found to regulate PI turnover. The role of [Ca2+]0 in subserving the PI response to EAAs was made evident.

Amino Acids↗
PubMed1994

Chronic venous stasis: not a predisposing factor for basal cell carcinoma on the leg. A histopathological study.

A histopathological study of 125 cases of basal cell carcinoma (BCC; out of 5,475 over a period of 5 years) occurring on the leg was performed. Nodular and superficial BCC were the most common patterns. No sclerosing type was observed, although prominent fibrosis was present in some cases of BCC associated with severe stasis changes. Stasis changes were found only in 25% of the cases suggesting that they do not represent a predisposing factor for the development of BCC on the leg.

Aged↗
PubMed1993

Microvenular hemangioma.

We report five cases of microvenular hemangioma, a recently described benign vascular disorder. Clinically, they were acquired, slowly enlarging angiomatous lesions without distinctive features. Histologically, these tumors were characterized by a proliferation of small-sized, irregularly branched, blood vessels throughout the dermis embedded in a desmoplastic stroma. In many areas, the endothelial cells were surrounded by pericytes. The architectural pattern of microvenular hemangioma make its differentiation possible from other cutaneous benign vascular lesions, namely, capillary hemangioma, lobular capillary hemangioma, angioblastoma, and hemangiomas in polyneuropathy, organomegaly, endocrinology, M protein, skin changes (POEMS) syndrome. A close relationship among these vascular proliferations is suggested.

Adult↗
PubMed1993

Seborrheic keratosis-like lesions in epidermodysplasia verruciformis.

A light microscopic study of 6 verrucous lesions with clinical features of seborrheic keratoses (SK) occurring on sun-exposed skin of 4 patients with epidermodysplasia verruciformis (EV) was performed. We observed the typical histological findings of SK in all cases. In addition, koilocytotic effects suggestive of EV were observed in the upper prickle layer and stratum granulosum. In 2 lesions, we also noted bowenoid changes suggesting possible early malignant transformation. Immunohistochemical study confirmed the presence of HPV in these lesions.

Adult↗
PubMed1993

Mycosis fungoides and eruptive epidermoid cysts: a unique response of follicular and eccrine structures.

A case of a patient who developed simultaneously mycosis fungoides (MF) and multiple, tiny eruptive cutaneous cysts on the face, neck and upper part of the trunk is reported. Histologically and immunohistochemically MF infiltrate was recognized not only in the upper part of the dermis and in the epidermis but also around and within the walls of cystic lesions. Furthermore, the eccrine structures were also involved by MF infiltrate. We emphasize that MF infiltrate can affect the follicular and eccrine structures inducing the formation of keratinous cysts. The clinical appearance of the facial lesions may be confused with Favre-Racouchot disease.

Aged↗
PubMed1993

Cutaneous lymphadenoma. A basal cell carcinoma with unusual inflammatory reaction pattern?

Two additional cases of cutaneous lymphadenoma (CL) are reported. The lesions presented as single nodules of many years' duration on the face. Histologically, the neoplasms consisted of irregularly shaped lobules immersed in a dense fibroblastic stroma involving the whole dermis and extending into the subcutaneous fat. Duct-like structures suggesting an eccrine differentiation were recognized. The lobules were composed of a rim of basaloid cells surrounding large epithelioid cells and lymphocytes. In some areas the basaloid lobules were only partly replaced by the inflammatory cells. Immunohistochemically, the intralobular inflammatory component was composed of a mixed B- and T-cell population and S-100-positive dendritic cells. The observation of these cases suggests that CL is not a distinct entity but may represent a basal cell carcinoma, possibly with pilar or eccrine differentiation, in which an immune host reaction pattern is exceedingly unusual.

B-Lymphocytes↗
PubMed1992

A simple method for electrical field stimulation of cultured granule cells.

A method suitable for electrical field stimulation of superfused primary cultures of cerebellar granule cells is described. A microchamber of about 0.5 ml was obtained by closing the culture dishes with a perspex plug equipped with stimulating electrodes and inlet-outlet tubing. Two-minute trains of electrical pulses (alternate polarity, 2-ms duration; 100 mA intensity; 10 V drop between electrodes; frequency 5, 10 and 20 Hz) applied to cultures kept at 27 degrees C, elicited a D-[3H]aspartate outflow which was frequency related, [Ca2+]0 dependent, tetrodotoxin sensitive. Moreover 2 trains of 10 Hz pulses (S1 and S2) at 30-min intervals caused an S2/S1 ratio equal or near to one, thus demonstrating that a steady-state condition had been achieved. The NMDA antagonist DL-2-amino-5-phosphonopentanoic acid (AP5) but not the non-NMDA antagonist, 6-cyano-7-nitroquinozaline-2,3-dione (CNQX), added before S2, significantly increased the electrically evoked tritium efflux, suggesting that the endogenous transmitter released during electrical stimulation activated an NMDA-mediated negative feed-back. This technique of electrical field stimulation seems particularly feasible to study the extent and time course of drug effects on spontaneous and evoked D-[3H]aspartate outflow.

2-Amino-5-phosphonovalerate↗
PubMed1992

HPV-related follicular cysts.

Five examples of follicular cysts with papillary projections protruding into the lumen are given. In all cases, the lining was epidermoid. The cystic cavity contained compact, eosinophilic keratinous material. Groups of vacuolated keratinocytes with overlying tiers of parakeratotic cells were seen on the top of the crests. In the intervening valleys, there were irregular clumps of keratohyaline granules. These changes are diagnostic cytopathogenic effects of viral papillomas. However, papillomavirus common antigens were not identified by immunohistochemistry.

Adult↗
PubMed1992

Pigmented trichoblastoma.

We report a case of trichogenic tumor with epithelial and mesenchymal components recapitulating the formation of hair germs. The epithelial lobules were highly pigmented and affected the full thickness of the dermis, extending into the subcutaneous fat. In addition, amyloid deposits were found within the epithelial lobules and in the stroma. The overall architecture was reminiscent of hair bulbs. Problems of differential diagnosis with other trichogenic tumors and pigmented tumors are discussed.

Adipose Tissue↗