Cytopathological and chemico-physical analyses of smears of mucosa surrounding oral piercing.

OBJECTIVE: The aim of this comparative study was to analyze cytopathologically and chemico-physically the mucosa surrounding oral piercing to correlate results with adverse tissue signs. MATERIALS AND METHODS: The tongue superficial mucosa of 15 young subjects (control group) and the superficial mucosa surrounding oral piercing of 15 young subjects (test group, TG) were smeared on slides, Papanicolaou stained and analyzed under the optical microscope. Some smears were prepared for (back-scattered) scanning electron microscope (SEM) and X-ray microanalysis to study piercing fragments. RESULTS: Smears of TG displayed a variable extent of bacterial cytolysis of epithelial cells, fungi, hyperkeratosis, parakeratosis, granulocyte infiltration, calcium formations and bacterial flora; the four last statistically significant (P < 0.05). Foreign bodies surrounded by keratinocytes were detected under both light and SEM. X-ray microanalyses highlighted piercing alloy aggression, ion release and an inverse gradient of ion concentration inside keratinocytes. CONCLUSIONS: The pathological findings in smears correlated with adverse effects of oral piercing. Ion release may be related to direct toxic effects and belated reactions because of metal sensitization. A strict regulation of piercing is warranted.

Selective melanocortin MC4 receptor agonists reverse haemorrhagic shock and prevent multiple organ damage.

BACKGROUND AND PURPOSE: In circulatory shock, melanocortins have life-saving effects likely to be mediated by MC4 receptors. To gain direct insight into the role of melanocortin MC4 receptors in haemorrhagic shock, we investigated the effects of two novel selective MC4 receptor agonists. EXPERIMENTAL APPROACH: Severe haemorrhagic shock was produced in rats under general anaesthesia. Rats were then treated with either the non-selective agonist [Nle4, D-Phe7]-melanocyte-stimulating hormone (NDP--MSH) or with the selective MC4 agonists RO27-3225 and PG-931. Cardiovascular and respiratory functions were continuously monitored for 2 h; survival rate was recorded up to 24 h. Free radicals in blood were measured using electron spin resonance spectrometry; tissue damage was evaluated histologically 25 min or 24 h after treatment. KEY RESULTS: All shocked rats treated with saline died within 30-35 min. Treatment with NDP--MSH, RO27-3225 and PG-931 produced a dose-dependent (13-108 nmol kg-1 i.v.) restoration of cardiovascular and respiratory functions, and improved survival. The three melanocortin agonists also markedly reduced circulating free radicals relative to saline-treated shocked rats. All these effects were prevented by i.p. pretreatment with the selective MC4 receptor antagonist HS024. Moreover, treatment with RO27-3225 prevented morphological and immunocytochemical changes in heart, lung, liver, and kidney, at both early (25 min) and late (24 h) intervals. CONCLUSIONS AND IMPLICATIONS: Stimulation of MC4 receptors reversed haemorrhagic shock, reduced multiple organ damage and improved survival. Our findings suggest that selective MC4 receptor agonists could have a protective role against multiple organ failure following circulatory shock.

Histological study on sinus lift grafting by Fisiograft and Bio-Oss.

The work aims to provide a histological investigation of Fisiograft, a PLA/PGA copolymer, used as filler for bone defects in humans. The study was performed on biopsies of sinus lifts where Bio-Oss and Fisiograft gel were applied as graft material. Bone regeneration was satisfactory in all sinus lifts, even when Fisiograft was applied alone. Due to remarkable osteoclast activity, Bio-Oss granules were cleared from the majority of biopsy cores. At histology, Fisiograft gel appeared as globes enveloped by fibroblasts, displaying an epithelial-like cell appearance. Due to its solubility in solvents, undegraded Fisiograft (recorded for 7 months or more) did not stain whereas degraded Fisiograft stained positive. The loose connective tissue, that surrounded Fisiograft and bone contained isolated mastocytes. Bone grew inside the loose connective and often reached the surface of Fisiograft by intervening cells. The results seem to indicate that Fisiograft may be considered both a polymer useful for fastening bone substitutes inside a defect and in addition a material capable of prompting bone regeneration, with or without the use of a bone substitute. In addition to space-former and space-maintainer functions, Fisiograft shows potential bone stimulation function, which may be labelled as osteopromotive capability.

Combined technique with polyethylene fibers and composite resins in restoration of traumatized anterior teeth.

Traumatized anterior teeth need quick esthetic and functional repair. Esthetic requirements of anterior teeth require the use of composite materials which, in the most complex cases, can be used in association with fibers so as to improve their mechanical resistance. Many kinds of fibers are available. The authors considered parameters such as physical properties, water absorption, ease of cutting and of laying. Polyethylene fibers appear to have the best properties in elasticity, translucency, adaptability, tenaciousness, resistance to traction and to impact. Fifteen children, between 7 and 13 years old, with crown fractures of the anterior sector were treated. In the case of a simple crown fracture, the missing part was restored by polyethylene fibers and composite resins. In the case of a complex crown fracture needing endodontic treatment, the fibers were used as a central core stump in order to restore the dental morphology. At control examinations, the teeth restored by this technique were acceptable, both in function and in aesthetics. Thus, the authors recommend this combined technique for predictable restoration of traumatized anterior teeth.

Protective effect of melanocortin peptides in rat myocardial ischemia.

The influence of the melanocortin peptide ACTH-(1-24) (adrenocorticotropin) on the consequences of short-term coronary ischemia (5 min) followed by reperfusion, and the effect of the long-acting melanocortin [Nle(4),D-Phe(7)]alpha-melanocyte-stimulating hormone (NDP-MSH) on the damage induced by a permanent coronary occlusion, were investigated in anesthetized rats. Ischemia was produced by ligature of the left anterior descending coronary artery. Reperfusion-induced arrhythmias [ventricular tachycardia (VT), ventricular fibrillation (VF)] and survival rate within the 5 min following reperfusion, blood levels of free radicals detected 2 min after reperfusion by electron spin resonance spectrometry, and amount of healthy myocardial tissue, measured 72 h after permanent coronary occlusion on immunohistologically stained serial sections, were evaluated. Postischemic reperfusion induced VT in all saline-treated rats, and VF and death in a high percentage of animals (87%). In rats treated i.v. (2.5 min after coronary occlusion) with ACTH-(1-24) (0.16-0.48 mg/kg) there was a significantly dose-dependent reduction in the incidence of arrhythmias and lethality. Ischemia/reperfusion caused a large increase in free radical blood levels; treatment with ACTH-(1-24) (0.48 mg/kg i.v.) almost completely prevented this increase. In rats subjected to permanent coronary occlusion, the amount of healthy myocardial tissue was much reduced in saline-treated rats, while in rats treated s.c. with NDP-MSH (0.27 mg/kg every 12 h) it was significantly higher. The present data demonstrate, for the first time, an unforeseen property of melanocortin peptides, i.e., their ability to significantly reduce both heart ischemia/reperfusion injury and size of the ischemic area induced by permanent coronary occlusion.

Neuroprotective effect of gamma-hydroxybutyrate in transient global cerebral ischemia in the rat.

The effect of gamma-hydroxybutyrate on the histological and behavioral consequences of transient brain ischemia was studied in the four vessel occlusion rat model. In saline-treated animals, 30 min ischemia caused a massive loss of neurons in the hippocampal CA1 subfield (normal neurons: 14%, 5%, 23% and 30% on the 3rd, 10th, 15th and 65th day after ischemia, respectively). gamma-Hydroxybutyrate - 300 mg/kg intraperitoneally (i.p.) 30 min before or 10 min after arteries occlusion, followed by 100 mg/kg i.p. twice daily for the following 10 days - afforded a highly significant protection (normal neurons on the 3rd, 10th, 15th and 65th day after ischemia: 88% and 91%, 80% and 80%, 91% and 90%, 72% and 71% in rats receiving the first dose before or after arteries occlusion, respectively). The ischemia-induced sensory-motor impairment was significantly attenuated in rats receiving the first dose of gamma-hydroxybutyrate before arteries occlusion. Finally, the ischemia-induced impairment in spatial learning and memory, evaluated starting 27 days after the ischemic episode, was significantly attenuated by gamma-hydroxybutyrate, either injected first at 30 min before or 10 min after arteries occlusion. Lower doses of gamma-hydroxybutyrate had no significant effect. In conclusion, these results indicate that gamma-hydroxybutyrate provides significant protection against both histological and behavioral consequences of transient global cerebral ischemia in rats.

Guided bone regeneration using titanium grids: report of 10 cases.

In order to ensure an adequate space where new bone can be formed in guided bone regeneration (GBR), most surgeons fill bone defects with biomaterials. In this work we evaluated new bone regeneration in 10 patients using only a blood clot protected with titanium grids and non-resorbable membranes, without any filling material. A manual measurement of the size of the bone defect, using a plastic probe, was performed at 2 surgical steps. After 5 months of treatment, a biopsy was taken from each patient, fixed and embedded in PMMA, examined microradiographically and morphologically to evaluate the newly-formed bone. Our results showed a good repair of the defects by bone regeneration (about 85% overall), high mineral density of new bone around the implants after 5 months, and steady state deposition processes. These results in GBR, without filling material, appear very promising for implantology and reconstructive odontostomatology practice.

Immunohistochemical detection of cell-cycle associated markers on paraffin embedded and formalin fixed needle biopsies of prostate cancer: correlation of p120 protein expression with AgNOR, PCNA/cyclin, Ki-67/MIB1 proliferation-scores and Gleason gradings.

Paraffin embedded and formalin fixed needle biopsies of prostate cancer (PC) were used to immunocytochemically detect the p120 nucleolar protein in relation to the Gleason histological gradings (GHG), the labelling indices of proliferating nuclear immunocytochemical markers (PCNA/Cyclin, Ki-67/MIB1) and the argyrophilic nucleolar region (AgNOR) rate. The twenty-six cases of PC (6 from large histological samples and 20 from needle biopsies) were equally distributed into low (< or = 6) or high (> or = 7) GHG groups. The p120 nucleolar protein immunocytochemical reaction was randomly expressed in large histological sections but uniformly distributed without gaps in needle biopsy sections. Only on the latter were quantitative values of PCNA/Cyclin (23.2 in low and 45.3 in high GHG), Ki-67/MIB1 (13.8 in low and 43.3 in high GHG) and AgNOR (5.0 in low and 7.5 in high GHG) related to those of p120 nucleolar protein (0.8 in low and 3.8 in high GHG). The values of all these cell cycle markers increased from low to high GHG of PC, all four reaching high statistical significance between the two groups (ANOVA-two tailed p < 0.0001). The PCNA/Cyclin index showed a higher positivity than the Ki-67/MIB1 index in PC with low GHG but not in PC with high GHG. In conclusion, paraffin embedded and formalin fixed PC needle biopsies exhibit a higher diagnostic PCNA/Cyclin than Ki-67/MIB1 index for cases presenting differentiated features, whereas p120 nucleolar protein detection seems to be a suitable marker of poorer outcome of PC.

Experimental ischemic liver injury and regeneration over 3 months: histological observations in the rat.

Liver histopathology of segmental portal ischemia occurring over a long-term period has not been previously described. For these reasons histological changes in the rat liver were studied from 1 h to up to 90 days after a left lateral and middle segmental portal obstruction. Within 3 h, the hepatocytes showed glycogen depletion in Rappaport zones 1 and 2 and pericentral and central lobular congestion of sinusoids and veins, whereas within 3 days, vein thrombosis appeared in the center of the lobule and liver necrosis was observed in Rappaport zones 2 or 3 or both, followed by restitutio ad integrum of the liver lobule morphology after 20-40 days. These results can be explained in light of two conditions occurring in the rat liver: (i) the peculiar low sensitivity of the liver to O2 debit and the protective or vasoactive effects used during hypoxia; and (ii) the sinusoidal network as a collateral source of the hepatic vascular system. Therefore, morphological assessment of this arteriolar and sinusoidal system, implicated in assuring efficient collateral blood supply in the rat liver with portal ischemia, is essential for understanding the mechanisms behind a natural and timely repair of ischemic injuries in the human liver.

Experimental acute infectious pancreatitis in rats: histological observations.

Microbic contamination has been shown to be a secondary pathogenetic factor in different models of acute pancreatitis. In this paper, we developed an experimental bacterial model of necrotizing acute pancreatitis (NAP). Forty rats were treated by direct inoculation of a suspension of a clinically isolated strain of Escherichia coli, with three different single 0.33 ml injections, into the head, body and tail of the pancreas. Twenty five rats were sham operated and injected with saline. All animals were sacrificed at 48 hours, 4, 6, and 12 days. This experimental model appeared easy to execute without evidence of mortality. Histomorphologically, haemorrhagic NAP was observed, with its final recovery and minimal residual and focal fibrosis of the gland. As reported in the literature, our data underline the relevance of the bacterial component on pathogenesis of NAP, especially as an aggravating factor.

Leptomeningeal carcinomatosis presenting as progressive multineuritis: clinical, pathologic, and MRI study.

Two patients developed a persistent illness characterized clinically and electrophysiologically by asymmetric involvement of spinal roots, of cranial and peripheral nerves. In the first case the disease was not discovered clinically but only after autopsy. The primary neoplasm remained undetected at autopsy. There was profound infiltration of the leptomeninges by tumor cells with features of metastatic adenocarcinoma. In the second patient onset of neurological symptoms occurred 16 years after surgery for breast cancer, which may be reasonably considered the primary malignancy-CSF cytology was positive only in the second patient in whom Gd-DTPA MRI supported the diagnosis. Our cases demonstrate that diagnosis in leptomeningeal carcinomatosis may be a challenging clinical problem.

Resistance to bacterial aggression involving exposed nonresorbable membranes in the oral cavity.

Bacterial colonies split implanted membranes that are exposed to oral biologic fluids as a consequence of dehiscence. The clinical and histologic behavior of 14 implanted polyurethane membranes was observed during the period of exposure to oral fluids for 2, 3, 4, and 6 weeks and without dehiscence (after 8 weeks). Statistical analysis indicated that the decrease in the number of neutrophils after 5 weeks, associated with the increase in the number of activated fibroblasts, cellular debris, giant cells, and aggression of bacteria, was statistically significant (from P < .05 and P < .01 for activated fibroblasts to P <.005 and P < .001 for neutrophilic cells). The increase in bacterial passage through the polyurethane membranes and in the number of giant cells and cellular debris after 8 weeks represents late dissolution of the membranes; the progressive increase of activated fibroblasts is significant because the longer the membrane resists, the better the cells can grow and give way to the process of tissue regeneration.

Quantitative and qualitative AgNORs rates of prostate cancer on needle core biopsies: a multicentric study.

From 1992 to 1993, the Scarpa Foundation Center of Pavia (SFCP) with 12 associated Italian Urological Units selected 40 cases of prostate diseases discovered on needle core biopsies, 5 of which were benign hyperplasias (BPH) in patients without clinical and morphological evidence of cancer and 35 prostate cancers (PRC) classified according to Gleason's histological grades (GLG) of PRC malignancy. Serum prostatic specific antigen (PSA) values were tested before clinical urological examination or biopsy or surgery. In all groups, AgNORs scores/nucleus were obtained by semi- and -automatic computerized image analysis and also by qualitative subjective counts of three observers on light microscopy. Our results pointed out a good correlation between PSA levels, GLG of PRC malignancy and AgNORs scores. The quantitative method showed an average number of AgNORS dots per nucleus between 2 and 3 in well differentiated PRC and higher than 3 in moderately differentiated and undifferentiated PRC, and exhibited more sensitivity over GLG3 than the qualitative investigation. The qualitative subjective count of AgNORs dots/nucleus seemed to be more reliable in differentiating the AgNORs scores of BPH (average of 1.81 dots/nucleus) from very well differentiated PRC with GLG1 + 2(average of 2.25 dots/nucleus) than quantitative analysis, which showed the same average value in both groups (2.11 dots/nucleus). For these reasons, also on needle biopsies of benign and malignant prostate diseases the subjective AgNORs count may aid the histological diagnostic judgement of malignancy, by avoiding misleading diagnoses of microscopic pictures of BPH cancer look likes and a predictive histologic malignant factor, in identifying PRC with low or high progression.

Experimental acute hepatic vein occlusion: histological observations in the rat.

The histological consequences of hepatic venous outflow obstruction were studied in the rat. Circulatory changes as venous congestion and interstitial fluid accumulation are followed by signs of cellular damage progressing till hemorrhagic infiltration and focal necrosis. These are quite completely reversible in a period of 15 days.

A theoretical rationale on the histogenesis of premalignant lesions and early carcinoma of the prostate.

Several localized non-malignant and dysplastic glandular proliferations of the prostate mimick well-differentiated invasive prostatic microcarcinoma (PMC). However, the basal cell layer (BCL) is intact and evident in benign hyperplasias and lacking in PMC; consequently, immunohistochemical reactions for BCL, by means of keratin 903 antibody, are essential for distinguishing PMC from cribriform clear cell hyperplasia (CCCH), typical tubular hyperplasia and tubular transitional metaplasia, tubular, microtubular and cribriform basal cell hyperplasias, post-undeveloped prepuberal (PUPPUH), florid (FH) and mesonephric remnant hyperplasias. Moreover, the hyperplastic basal cells are also immunostained for prostatic specific antigen (PSA). The identification of myoepithelial cells (positive for keratin 903, actin and S100 protein antibodies) allow the diagnosis of prostatic sclerosing adenosis. Basement membrane (BM) and BCL are focally absent in post-atrophic hyperplasia (PAH), PUPPUH, FH and in extratubulo-alveolar gemmations of dysplasic lesions such as prostatic intraepithelial neoplasia (PIN), adenomatous atypical hyperplasia (AAH) and adenosis, where hypercromatic nuclei and enlarged nucleoli are the most important cytological criteria for defining malignant changes. Two putative oncogenic stages have been identified in the present work on these morphological grounds by critically examining the histogenetic hypoteses given in the literature on PMC precursors. The first is characterized by precancerous conditions such as PAH, PUPPUH, CCCH and FH that may become dysplastic though not necessarily; the second includes precancerous lesions, namely atypical tubulo-alveolar budding-in or budding-off as PIN and AAH, respectively, that may evolve towards PMC. The histogenesis of rare prostatic carcinomas are also considered. Basal cell and adenoid-cyst carcinomas seem to originate from atypical basal cell proliferations and metaplastic (transitional, adenosquamous, mucinous) carcinomas from basal and columnar-cells. Transitional and endometrioid carcinomas affect the mesonephric part of the prostate. Prostatic endocrine cells may give rise to carcinoid tumors, whereas some well-differentiated or anaplastic carcinomas may present more or less numerous endocrine cells and/or Paneth-like cells by means of a prosoplastic and ketaplastic process from neoplastic elements that underwent a stem cell backward differentiation.

Age-related distribution of endocrine cells in the human prostate: a quantitative study.

A morphometric analysis was performed to obtain quantitative data on age-related changes in prostatic endocrine cell (PrEC) density. Sixty prostates from subjects aged 14-74 years were studied with a semi-automatic image analysis system (ASM 68K, Leitz) applied to sections immunostained for chromogranin A-reactive cells. The highest density of PrECs (0.366 cells/mm of epithelial length) was found in the 25-54 year age group, which was significantly different from that found in prostates of the younger (0.311 cells/mm) and the older (0.261 cells/mm) age groups. The data probably reflect the higher incidence of incompletely developed glandular units in the younger group and the formation of new alveoli related to the usual glandular hyperplasia that occurs with increasing age in the older group.

Proliferating cell nuclear antigen/cyclin in incidental carcinoma of the prostate.

Monoclonal antibody to proliferating cell nuclear antigen (PCNA) has been used to identify the growth fraction in ten cases of benign prostatic hyperplasia (BPH), in 20 prostatic microcarcinomas (PMC) and in 30 cases of infiltrating prostatic carcinoma (PC). Ten year follow-up was available on all cases by means of clinical, serological, radiological and echographic examinations. The percentage of PCNA-staining nuclei was independently counted by two observers. Statistical analysis showed significant differences between PCNA/cyclin score of BPH and PMC without recurrences with respect to those of PMC with progression and of PC. PCNA immunostaining may represent a reliable method for assessing cellular proliferative activity. It may be used as a more powerful diagnostic hallmark of PMC than patterns of non-malignant microglandular proliferation and is also a useful additional test for assigning histological grades to PMC and PC. Statistical analysis indicated that PCNA/cyclin index was an independent significant prognostic indicator of predicting malignant progression (P < or = 0.01) and survival rates (P < or = 0.05) of PC and PMC (> 5 mm diameter).

Sclerosing adenosis of the prostate. Report of three cases with electronmicroscopy and immunohistochemical study.

Three cases of rare variant of prostatic adenosis with the features of sclerosing adenosis, an uncommon lesion sometimes confused with prostatic carcinoma, are reported. The lesions consisted of a small, single nodule in prostates otherwise showing typical adenomatous and fibromuscular hyperplasia. The lesions were composed of crowded small glands, small solid nests and individual cells embedded in a cellular stroma. Immunohistochemistry showed that the glands were lined by basal cells positive for the high-weight keratins (EAB-903 and AE-3), a finding which confirms the benign nature of the lesion. S-100 protein and smooth muscle actin were also positive in the same basal cells suggesting myoepithelial differentiation, a character not found in basal cells outside this lesion. This finding was confirmed at ultrastructural level by the finding of numerous thin filaments in the cytoplasm of basal cells. It is important to recognize this lesion in order to avoid confusion with well-differentiated prostatic carcinoma.

The experimental systemic perfused lung: histological observations in the dog.

An experimental model of pulmonary hypertension was obtained in the dog implanting the left main pulmonary artery in the descending thoracic aorta. The main histological lesions consisted in an increased muscularity of the pulmonary artery itself and of its lobar branches.