Chemopreventive potential of phenolic compounds in oral carcinogenesis.

OBJECTIVE: To evaluate the chemopreventive potential of phenolic compounds - potassium apigenin, cocoa, catechins, eriocitrin and rosmarinic acid in oral carcinogenesis induced in hamsters by means of the topical application of 7,12-dimethylbenz(a)anthracene(DMBA). STUDY DESIGN: An experimental study at the University of Murcia. METHODS: 50 male Syrian hamsters (Mesocricetus auratus) were divided into five groups of ten: Group I (control group): 0.5% DMBA; Group II: 0.5% DMBA+1.1mg/15ml potassium apigenin; Group III: 05% DMBA+2.5mg/15ml cocoa catechins; Group IV: 0.5% DMBA+6mg/15ml eriocitrin; Group V: 0.5% DMBA+1.3mg/15ml rosmarinic acid. The flavonoids were administered orally. All the animals were sacrificed after 12 weeks. Macroscopic, microscopic and immunohistochemical (PCNA and p53) analyses of the lesions were performed. RESULTS: All the groups treated with phenolic compounds showed lower incidences of tumour, greater differentiation and lower scores in the tumour invasion front grading system in comparison with the control group. Potassium apigenin and rosmarinic acid achieved the best results, the former considerably reduced the carcinoma tumour volumes developed and both significantly reduced the intensity and aggression of the tumours. Immunoexpression of PCNA and p53 were significantly altered during DMBA-induced oral carcinogenesis. CONCLUSIONS: Animals treated with phenolic compounds, particularly potassium apigenin and rosmarinic acid, showed a lower incidence of tumours.

Effect of the phenolic compounds apigenin and carnosic acid on oral carcinogenesis in hamster induced by DMBA.

OBJECTIVE: To investigate oral carcinogenesis in hamster induced by the topical application of 7,12-dimethyl benzanthracene (DMBA) to evaluate the different lesions produced and the possible preventive effects of the phenolic compounds apigenin (flavone) and carnosic acid (diterpene). MATERIALS AND METHODS: Thirty-two Syrian hamsters were divided into three groups: I: 0.5% DMBA (n = 12); II: 0.5% DMBA + potassium apigenin (n = 8); III: 0.5% DMBA + carnosic acid (n = 12). All the animals were sacrificed after 11 weeks, and a macroscopic and light microscopic study was made of the lesions. RESULTS: The largest number of neoplasms, showing the most aggressive biological behavior, corresponded to the control group. The group treated with potassium apigenin ranked second in tumor incidence, although the tumors were not very aggressive behavior. In the group treated with carnosic acid, only one malignancy was recorded, showing the smallest volume of all the recorded tumor lesions. CONCLUSIONS: Our findings indicate that both potassium apigenin and carnosic acid have chemoprotective effects against carcinogenesis induced by DMBA in hamster.

A bioactive sol-gel glass implant for in vivo gentamicin release. Experimental model in Rabbit.

Biomaterial pieces with osteogenic properties, suitable for use in the treatment of bone defects, were synthesized. The materials, which avoid bone infections, are exclusively composed of gentamicin sulfate and bioactive SiO2-CaO-P2O5 sol-gel glass (synthesized previously), and were manufactured by means of uniaxial and isostatic pressure of the mixed components. After implanting the pieces into rabbit femur, we studied (1) antibiotic release, determining the concentration in proximal and distal bone, liver, kidney, and lung as a function of time, and (2) bone growth as a consequence of the glass reactivity in the biological environment. The results demonstrated that the implants are good carriers for local gentamicin release into the local osseous tissue, where they show excellent biocompatibility and bone integration. Moreover, these implants are able to promote bone growth during the resorption process.

Clinicopathological characteristics of tongue piercing: an experimental study.

BACKGROUND: This study attempts to remedy the situation that no morphological studies exit of tongue piercing. METHODS: The tongues of eight Beagles were pierced with titanium implants. The animals were then divided into four groups: 1 week, 2 weeks, 1 month and 3 months for clinical-photographic and histopathological studies. RESULTS: Group I: clinically, erythema at both orifices and, microscopically, granulation tissue covering the surface of the canal and infiltrates of polynuclear neutrophils. Group II: persistence of erythema and of the granulation tissue, with the edges of the epithelium showing signs of regeneration. Group III: granulation tissue alternating with fibrosis; epithelium covering the sides of the canal. Group IV: fibrosis substituting the granulation tissue and almost complete re-epithelialization of the canal. All groups, except group I, numerous foreign body-type granulomas. CONCLUSIONS: Tongue piercing provokes fibrous reparation with almost total re-epithelialization of the perforated zone and foreign body-like granulomatous inflammation.

[Absence of chromosomic and genotoxic damage from the radiation dose administered in scintigraphic examinations]. / Ausencia de daño cromosómico y genotóxico inducido por la dosis de radiación administrada en las exploraciones gammagráficas.

INTRODUCTION: The cytokinesis-blocked (CB) micronucleus test (MN) on irradiated human lymphocytes is normally used to evaluate chromosomal and genotoxic damage produced by various physical and chemical agents. OBJECTIVE: Determine any possible genotoxic effect induced by the different types of ionizing radiation employed in medical diagnostic radiology and nuclear medicine. MATERIAL AND METHODS: The frequency of the MN appearance was determined in CB lymphocyte cultures of a total of 4 different groups of patients: (1) in 35 supposedly healthy volunteers to establish the MN spontaneous frequency in the medium; (2) in 9 volunteers to measure the in vitro dose-response curves in order to calculate the MN frequency following X-ray irradiation and gamma radiation; (3) in 25 patients in whom a specific diagnostic and/or therapeutic procedure employing diagnostic radiology techniques involving X-ray exposure was applied, and (4) in 26 patients in whom the diagnostic procedure in question involved nuclear medicine techniques (scintiscan). RESULTS: A lineal relationship was observed between the MN frequency and the dose of ionizing radiation administered in vitro, both in X-rays and gamma radiation. A significant increase in the MN is observed after radiation is given to patients during medical diagnostic radiology examinations when compared with the control values obtained from the same patients prior to being subjected to the radiological procedure (p < 0.01). No significant MN increase is observed following exposure to radiation involved in diagnostic examinations in patients studied in Nuclear Medicine. CONCLUSION: Ionizing radiation employed in complex medical diagnostic radiology examinations produces a significant increase in the MN appearance frequency and as such indicates both radiation induced chromosomal and genotoxic damage. However, the ionizing radiation used in diagnostic nuclear medicine examinations does not induce any significant increase in MN appearance frequency.

[Nephrogenic bladder adenoma associated with glandular cystitis. Immunohistochemical study and significance]. / Adenoma nefrogénico vesical asociado a cistitis glandular. Estudio inmunohistoquímico y significado.

A histopathological and immunohistochemical study of a case of nephrogenic adenoma of the bladder associated to glandular cystitis is presented with a very similar immunostaining to adenomatoid tumors in other organs and probably of a mesothelial origin. Its pathogenesis seems to correspond to a metaplastic change of the bladder's urothelium through anomalous differentiation of the reserve cells faced with different irritating agents. Because of its benign characteristics, we think that treatment can be confined to endoscopic observation and conservative technique.

Biocompatibility and in vivo gentamicin release from bioactive sol-gel glass implants.

Biomaterial pieces, with suitable osteogenic properties for use in the treatment of bone defects and the capability to avoid bone infections, have been synthesized. These materials are composed exclusively of gentamicin sulfate and bioactive SiO(2)-CaO-P(2)O(5) sol-gel glass (previously synthesized). Implant processing was achieved by uniaxial and isostatic pressure of the components mixture. After implanting the pieces into rabbit femur, we studied (i) the antibiotic release, determining the concentration in proximal and distal bone, liver, kidney, and lung as a function of time; and (ii) the bone growth resulting from the glass reactivity in the biologic environment. The results indicate that the implants are good carriers for local gentamicin release in the osseous tissue, exhibiting excellent biocompatibility and bone integration. Moreover, these implants are able to promote bone growth during their resorption process.

Granuloma faciale: an ultrastructural study.

Granuloma faciale is an uncommon process that can easily be confused with other skin diseases. To avoid incorrect treatment, correct diagnosis is of primary importance. A diagnosis of granuloma faciale can be made by a microscopic study of the dense granulomatous infiltrate in the reticular dermis with abundant polynuclear eosinophils and by an ultrastructural study of the eosinophils, which show characteristic alterations in their cytoplasmatic granules. The absence of Langerhans granules differentiates granuloma faciale from histiocytosis X.

The effects of different antineoplastic agents and of pretreatment by modulators on three melanoma lines.

BACKGROUND: The chemotherapy of melanoma patients must be improved because of the naturally poor response and acquired resistance of this disease. METHODS: The authors used mouse (B16F10) and human (SK-MEL-28 and SK-MEL-1) melanoma lines for in vitro treatment with melphalan, lomustine, fotemustine, and 4-hydroxyanisole (4-HA) alone, combined and after pretreatment with buthionine sulfoximine (BSO), ethacrynic acid (EA), and azelaic acid (AZA). RESULTS: Melphalan was the most effective individual drug, followed by lomustine, fotemustine, and 4-HA. The simultaneous administration of two agents was disappointing, although some combinations slightly improved the response compared with the individual treatments. Pretreatment with BSO enhanced the cytotoxicity of melphalan and lomustine 10-fold in B16F10 and 7.5-fold in SK-MEL-28, increasing the toxicity of fotemustine in all 3 lines. EA potentiated lomustine and fotemustine 9-fold and melphalan 5-fold in B16F10 and SK-MEL-28. AZA increased the effectiveness of lomustine and fotemustine in B16F10 and to a lower degree in the two human lines. 4-HA was the poorest drug for sensitization; only B16F10 BSO followed by 4-HA treatment demonstrated increased toxicity, and all other combinations with 4-HA were negative or antagonistic. There was a strong relationship between dopa oxidase activity and the toxicity of 4-HA. CONCLUSIONS: B16F10 was the most sensitive to all treatments and SK-MEL-1 the most resistant. Melphalan was the most active individual drug and 4-HA the least. Combinations of two drugs did not result in improved activity compared with drugs administered alone. Pretreatment with modulator seems to be a potential method for enhancing some treatments.

Relationship between 4-hydroxyanisole toxicity and dopa oxidase activity for three melanoma cell lines.

We studied the response of mouse B16F10 and SK-MEL-28 and SK-MEL-1 human melanoma cell lines to treatment with 4-hydroxyanisole (4-HA), and attempted to relate the response to the dopa oxidase levels and the morphological characteristics of each cell line. Clear dose-response curves were observed after 24 h of treatment in each cell line, the 4-HA being more toxic to the B16F10 cells, with an ID50 value of 215 microM. This was much lower than that observed for the SK-MEL-28 and SK-MEL-1 cell lines (ID50 of 5.98 mM and 7.17 mM, respectively). There was a direct relationship between toxicity levels and dopa oxidase activity, since the highest specific activity was obtained for B16F10 (15.9 mU), while lower activity was registered for SK-MEL-28 (4.59 mU) and SK-MEL-1 (1.24 mU), which also showed lower 4-HA toxicity. Morphologically, we observed the typical characteristics of cellular injury, with swelling and dilation of the internal membranes and organelles, an increased number of vacuoles, and an increased number of abnormal multilamellar melanosomes or thick clumps of irregularly distributed melanin. On the other hand, we observed that the two cell lines with the lowest dopa oxidase activity contained more mature fully melanized melanosomes than B16F10, pointing to possible alterations in the melanosome transference mechanism and lower enzymatic activity in the mature melanosomes of these two human cell lines.

Azelaic acid was sensitizing effect in the chemotherapeutic treatment of several melanoma cell lines.

Chemotherapy for melanoma results in low response and must be reinforced with sensitizer compounds. We believed that azelaic acid (AZA) could modulate melanomas' resistance to antineoplastics. Therefore we tried to compare in vitro treatment with antineoplastics alone versus AZA treatment followed by antineoplastics. We carried out MTT assays to evaluate the cytotoxicity of melphalan, lomustine (CCNU), fotemustine, and 4-Hydroxyanisole (4-HA) on three melanoma lines (B16F10, SK-MEL-28, and SK-MEL-1), and the modulating effect of pretreatment with AZA (1 mM). AZA showed a dose-dependent antineoplastic activity on the three lines. Melphalan was the most active drug followed by CCNU, fotemustine, and 4-HA. The most sensitive line was B16F10 and the least sensitive was SK-meL-1. Previous treatment with AZA of B16F10 reinforced the effect of melphalan (2.5 times), CCNU (10 times), and fotemustine (14 times); whereas for SK-MEL-28 and SK-MEL-1, only the cytotoxicity of CCNU and fotemustine increased. An antagonist effect was produced by 4-HA on all three lines. We concluded that AZA enhances in vitro cytotoxicity of CCNU and fotemustine.

Ultrastructural investigation of lead-induced intranuclear inclusion bodies in mice.

By means of optical and electron microscopy and by atomic absorption spectrophotometry in a graphite chamber, this study evaluated the effect of temperature (22-35 degrees C) on lesions in the kidney, liver, and brain, and on concentrations of lead caused by the administration of 2 and 5 mg/kg/IP of lead acetate to Swiss mice. The most pronounced effects were observed in the kidney and in groups of animals receiving the highest doses (5 mg/kg at 22 and 35 degrees C). These effects consisted of significantly higher (p < .05) lead concentrations in the tissues, a significant decrease (p < .05) in kidney weights, and progressive kidney atrophy and fibrosis with, at the ultrastructural level, constant intranuclear inclusions, which were also observed in the cytoplasm of renal and endothelial cells.

Comparative study of experimental ocular melanoma using two implantation techniques of B16-F10 melanocytes.

OBJECTIVE: The aim of this work was to evaluate the behaviour of B16-F10 melanoma cell cultures implanted in the anterior chamber of the eye of New Zealand white rabbits by studying the clinical-pathological and ultrastructural characteristics of the lesions. METHODS: One group (A) (consisting of 30 rabbits) was transclerally inoculated (1 mm from sclero-corneal limbus) with 4 x 10(6) melanocytes and another group (B) (also 30 animals) was inoculated once per week for 3 consecutive weeks with 5 x 10(6) cells (total 15 x 10(6)); 30 animals acted as the control group (C). All the lesions were processed for optic and electronic microscopy. RESULTS: Tumoral growth in group A was 43% (13/30) and in group B 80% (24/30). All lesions were pigmented and none perforated the eyeball. Microscopically, they were a mixture of epithelioid and fusiform cells disposed around the blood vessels. Ultrastructurally, the presence of melanosomes in different stages of maturation and aberrant melanosomes were characteristic. CONCLUSION: We suggest that the transcleral inoculation of 15 X 10(6) B16-F10 melanocytes into the anterior chamber of the eye of New Zealand white rabbits may be a valid and reproducible method for obtaining an experimental ocular melanoma model.

The behavior of two cell lines obtained from murine (B16-F10) and human (G-361) melanomas implanted into the eyes of New Zealand white rabbits, and their microscopic, immunohistochemical and ultrastructural appearances.

A transcleral inoculation of 15x10(6) melanocytes of the B16-F10 and G-361 cell lines was carried out in the anterior chamber of one eye in New Zealand white rabbits. Tumor growth occurred in 24 eyes (77%) of the B16-F10 group and in 22 (73%) of the G-361 group. The tumors of the latter group were mostly amelanic and showed local aggression with ocular perforation and extrascleral growth one month post-implant, while the tumors of the B16-F10 group were intensely pigmented and grew over the iris although they did not perforate the eyeball. Microscopically, the tumors of both groups were of the mixed type, made up of epithelioid and fusiform melanocytes. S-100 protein and Nki C3 monoclonal immunohistochemical techniques showed a positive immunoreaction in all cases of tumor growth. Ultrastructurally, the G-361 melanocytes showed a few melanosomes corresponding to maturity state II and, occasionally, state III, while totally melanized state IV cells predominated in the B16-F10 group. Aberrant melanosomes were common in both groups. The inoculation of 15x10(6) melanocytes of either cell line was useful to produce ocular melanomas.

Abnormal melanosomes: ultrastructural markers of melanocytic atypia.

To identify possible ultrastructural markers of melanocytic atypia, a quantitative ultrastructural study was made of melanocytes found at the dermal-epidermal boundary of normal skin and in benign, premalignant, and malignant melanocytic lesions. There was a significant increase (p < 0.05) in the number of melanosomes per melanocyte in the premalignant and malignant lesions compared with the number observed in the benign lesions. There was a significantly higher number (p < 0.05) of abnormal melanosomes (with irregularities in the laminar matrix or with a granular or clumpy matrix) in the premalignant and malignant lesions, which suggests that the presence of a high percentage of abnormal melanosomes might act as a useful ultrastructural marker in the diagnosis of melanocytic atypia.

Effects of various antineoplastic agents on an established human melanoma cell line (G-361).

An established human melanoma cell line was treated with several concentrations of three antineoplastic drugs: melphalan (0.016, 0.032, 0.16 microns), CCNU (1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea) (0.04, 0.21, 0.42 microM), and 4-OHA (4-hydroxyanisole) (4.01 x 10(-4), 1.20 x 10(-3), 2.4 x 10(-3) microM), and the effects on cell growth and viability were compared. 24 hours after treatment, 4-OHA (ID50 = 2.4 x 10(-3) microM) was more cytotoxic than melphalan (ID50 = 0.016 microM) and CCNU (ID50 = 0.21 microM). However, after 96 hours exposure, the most effective drug was CCNU (growth rate = -1.277), which caused the death of the culture. This was followed by melphalan (growth rate = -1.024) and finally 4-OHA (growth rate = -0.69). Similar ultrastructural cell injuries were observed after the use of the three drugs: the dilation of endoplasmic reticulum vesicles and the nuclear membrane; mitochondria swelling; and the existence of lamellar structures and cytoplasmic vacuoles.

Ocular melanoma: an experimental model in New Zealand white rabbits.

An experimental model is suggested for reproducing ocular melanoma in New Zealand white rabbits using B16 melanoma cells and protocols differing with respect to either tumour origin (subcutaneous fragments of melanoma B16 or B16-F10 tumour cell cultures) or implant site (the anterior chamber or subchoroidal). In 20 animals, 20 mg of methylprednisolone acetate was injected subconjunctivally as a local immunosuppressant. The only protocol resulting in tumour was inoculation of 4 x 10(6) B16-F10 melanocytes into the anterior chamber of the eye. Trans-scleral injections of cell suspensions produced tumour growth in 43% (13/30) of animals so treated. Thirteen animals developed non-neoplastic pigmented lesions formed of numerous melanophages. Another 19 animals showed non-pigmented lesions caused by reaction to the surgical procedures. Subconjunctivally injected methylprednisolone acetate did not increase the incidence of tumour growth.

[Oropharyngeal pemphigus vulgaris]. / Penfigo vulgar orofaringeo.

Etiologic and pathogenic as well the Pemphigus vulgaris is an autoimmune disease, being its symptomatology polysystemic. Accordingly, under the diagnostic viewpoint, must be considered as a multidisciplinary illness. Either the evolutive course, the differential diagnosis or the treatment emphasizes the importance of the attendance of these patients ambulatory or hospitalized. An exclusively ENT case of pemphigus vulgaris seen by the AA. compelled them to a perusal of the bibliography of the subject, in order to update the problems of diagnosis and treatment of the disease.