Juxtaoral organ: an anatomical finding to be considered.

The juxtaoral organ (JOO) is a vestigial anatomical structure which is not usuallydescribed in lectures and classic texts of general histology and oral histology, despiteit being included in the "Terminologia Histologica: International terms for humancytology and histology". Although there is evidence about its histological structure,there are no macroscopic anatomical reports about it. We report the finding ofa structure of glandular macroscopic appearance in a horizontal section of a plastinatedhuman head belonging to the Morphology Laboratory of the Department ofBiomedical Basic Sciences at the University of Talca. Due to its location, dimensionsand anatomical relations, we determined it to be the JOO. Using a digital calliper, wemeasured the anteroposterior and transverse dimensions of the JOO and observedits anatomical relationships with neighbouring structures of clinical relevance. Weconclude that the JOO is relevant to surgical practice due to its anatomical relationswith relevant structures such as inferior third molar and lingual nerve. Its clinicalapplication lies in the differential diagnosis with invasive processes of malignantneoplasia originating in the oral cavity.

Celecoxib: Antiangiogenic and Antitumoral Action / Celecoxib: Acción Antiangiogénica y Antitumoral

SUMMARY: Angiogenesis, a process by which new blood vessels are generated from pre-existing ones, is significantly compromised in tumor development, given that due to the nutritional need of tumor cells, pro-angiogenic signals will be generated to promote this process and thus receive the oxygen and nutrients necessary for its development, in addition to being a key escape route for tumor spread. Although there is currently an increase in the number of studies of various anti-angiogenic therapies that help reduce tumor progression, it is necessary to conduct a review of existing studies of therapeutic alternatives to demonstrate their importance.

La angiogénesis, proceso por el cual se generan nuevos vasos sanguíneos a partir de otros preexistentes, se encuentra comprometida de forma importante en el desarrollo tumoral, dado que por necesidad nutritiva de las células tumorales se generarán señales pro angiogénicas para promover este proceso y así recibir el oxígeno y los nutrientes necesarios para su desarrollo, además de ser una ruta de escape clave para la diseminación tumoral. Si bien, actualmente existe un aumento en la cantidad de estudios de diversas terapias anti angiogénicas que ayudan a reducir el avance tumoral, es necesario realizar una revisión de los estudios existentes de alternativas terapéuticas para demostrar su importancia.

Allele-specific mutations involved in the pathogenesis of endemic gallbladder carcinoma in Chile.

Although gallbladder carcinoma is one of the most frequent neoplasms in Chile, there is limited information about the molecular changes involved in its pathogenesis. We investigated the incidence of ras gene mutations and loss of heterozygosity (LOH) at the following genes/loci: p53, DCC, rb, 5q 3p, 8p, and 9p. We precisely microdissected 194 relevant areas from paraffin-embedded microslides from 25 gallbladder carcinomas and their accompanying nonneoplastic lesions (which were present in 15 cases) from patients in Chile. The specimens were analyzed by PCR-based assays for LOH, and we designed a RFLP method for ras mutations and immunohistochemistry for p53 protein overexpression. We determined that LOH at p53 (91%), 9p (50%), 8p (44%) and DCC (31%) are frequent events and that LOH at p53, 9p, and DCC are early events, while ras mutations and LOH at 3p, rb, and 5q occurred occasionally. LOH at p53 occurred more frequently and earlier than protein overexpression. The mean number of mutations present in invasive carcinomas was 2.1, and in six cases, LOH at the p53 gene was the sole mutation detected. The same allele was lost in 61 (93%) of 71 nonneoplastic foci as in the corresponding invasive carcinomas for all four mutations studied. The odds of this occurring by chance are approximately 4 x 10(-15). Although clonality cannot be excluded, allelic loss appears to be highly directed, but the mechanism for allele-specific mutations remains to be determined.

DNA ploidy pattern and tumor suppressor gene p53 expression in gallbladder carcinoma.

The relationship between p53 gene expression and DNA content in advanced gallbladder carcinoma was studied. Fifty-three cases of advanced gallbladder carcinoma (45 primary tumors and 8 metastases) were analyzed, p53 protein expression was determined by immunohistochemistry, DNA content was measured by cytophotometric techniques. Study subjects included 45 (85%) female and 8 male patients, with an overall mean age of 58.6 years. Positive staining for p53 protein was observed in 27 (51%) cases. In subserosal tumors, the expression was significantly less than that in tumors that reached the serosa (P = 0.01). Twenty-nine (55%) cases were diploid and 24 were aneuploid. Sixty-seven % of primary tumors were diploid, whereas 87% of metastases showed an aneuploid DNA content. Both diploid and aneuploid tumors were positive for the p53 protein in the same proportion, and p53 was also expressed equally in both primary and secondary tumors. In advanced gallbladder carcinoma, the expression of the p53 gene was earlier than the accumulation of abnormal quantities of chromosomal DNA in the tumor cells. The determination of these events as markers in preneoplastic lesions is warranted in gallbladder carcinogenesis.

p53 protein overexpression in gallbladder carcinoma and its precursor lesions: an immunohistochemical study.

Gallbladder carcinoma is one of the most frequent neoplasms diagnosed in Chile. Although the premalignant lesions have been extensively studied and are well characterized, there is only limited information about the genetic abnormalities that might be important in the pathogenesis of gallbladder carcinoma or that might have prognostic implications. The present study evaluates the immunohistochemical expression of p53 protein in premalignant lesions and invasive carcinoma of the gallbladder, and correlates the p53 expression with histological type, grade of differentiation, and level of invasion of the tumor. The authors studied the immunohistochemical p53 protein overexpression in 52 gallbladder carcinomas, 47 carcinomas in situ (CISs), 34 dysplasias, and 10 specimens with chronic cholecystitis containing normal and metaplastic epithelium. A semiquantitative scoring system was used to assess the p53 reactivity. p53 overexpression was found in 34 of 52 (65.4%) carcinomas, 21 of 47 (44.7%) CISs, and 11 of 34 (32.4%) dysplasias. There were no significant differences in p53 expression in premalignant lesions associated with invasive carcinoma and those that were not. Normal and metaplastic epithelium did not overexpress p53 protein. In adenocarcinomas, no correlation was found between p53 protein overexpression and histological subtype, grade of differentiation, or level of invasion. The high incidence of p53 overexpression in gallbladder carcinoma and its presence in dysplasia, even in specimens without invasive carcinomas, suggests that this abnormality is an important and early event in the pathogenesis of the tumor. The progressively increasing incidence of p53 overexpression observed from premalignant lesions to invasive tumor provides additional support to the view that this is the usual route for the development of infiltrating gallbladder carcinoma.

Comparison of mutagenic activity of bile between Chilean and Japanese female patients having cholelithiasis.

The mutagenic activity of bile was compared between Chilean and Japanese female patients having cholelithiasis by the Ames assay using Salmonella typhimurium tester strain TA98 in the presence of S9 mix with blue rayon adsorption technique. A reason for conducting the present investigation is that Chile and Japan have the highest mortality rates for the gallbladder cancer (GBC) in the world. Of 24 bile samples collected in Chile, 20 (83.3%) samples showed mutagenicity. In the case of Japanese bile, 21 (80.8%) of 26 and 5 (19.2%) of 26 cases were mutagenic in samples from high- and low-risk areas for GBC, respectively. Therefore, both the Chilean and the Japanese samples collected in high-risk areas showed higher mutagenic rates than the Japanese ones in a low-risk area, with a statistical significance (p < 0.001), chi-square test). The average number of revertant colonies were 128 +/- 92 (mean +/- SD), 62 +/- 14 and 66 +/- 13, respectively, when the blue rayon extracts of 200 microliters bile were applied to the Ames test. Thus, Chilean bile had a tendency to show a higher mutagenic activity than Japanese.

Peripheral pigmented neuroectodermal tumor of infancy with rhabdomyoblastic differentiation.

A case of a 6-month-old male with a peripheral pigmented neuroectodermal tumor of the right popliteal region is presented. The tumor disclosed neuroblast-like and melanoblast-like cells and on electron microscopy tumor cells with rhabdomyoblastic differentiation. The patient is well and alive and without evidence of disease three years after the initial diagnosis. This unusual case gives further support to the current theory of a common origin for central and peripheral neuroectodermal neoplasms and related entities.

Preoperative chemoradiotherapy in the treatment of gallbladder cancer.

Gallbladder cancer is generally associated with a poor prognosis, with local recurrence being the main pattern of failure. In an attempt to improve on the present status of management, we evaluated a prospective Phase II study involving preoperative 5-fluorouracil and radiation. Among 27 eligible patients with a potentially resectable gallbladder cancer detected after cholecystectomy, 18 were treated with preoperative radiation (4500 cGy; 180 cGy/fraction, 5 days/week) concurrent with a continuous infusion of 5-fluorouracil (350 mg/m2/day, days 1-5 and 21-25). Toxicity included leukopenia (8 patients) and thrombocytopenia (7 patients). Delay in surgery due to hematological toxicity was seen in 6 patients. Of the 18 patients, 15 underwent a reoperation. Resection was performed in 13 (86%). Pathologic findings after reoperation revealed residual tumor in both liver and lymph nodes in 3 patients. At a median follow-up of 24 months, 7 patients are alive. Among the patients who died after curative resection, local recurrence was demonstrated in only 1. This is the first report concerning preoperative chemoradiation in gallbladder cancer. To assess its effect on survival, a prospective randomized trial will be necessary.

The uncombable hair syndrome.

We report a case of "uncombable hair syndrome" that occurred in a boy who had no other abnormalities. The diagnosis was clinically suspected and confirmed by examination of the scalp hair, which was treated with a bath of gold. Scanning electron microscopy was used for examination. The main defect of the hair was a longitudinal, canalicular depression in one side. The same defect was demonstrated by light microscopy in the transverse cut of the hair embedded in epoxy resin.

Peritoneal pseudomyxoma in a child with a gallbladder Peutz-Jeghers-like hamartomatous polyp: a case report.

A 2-year, 6-month-old boy with peritoneal pseudomyxoma had a hamartomatous Peutz-Jeghers-like polyp in the gallbladder. The morphological pattern of the polyp was very characteristic of what is usually considered an hamartomatous polyp. The patient presently reported has no clinical characteristics of Peutz-Jeghers syndrome. The peritoneal pseudomyxoma creates differential diagnostic problems with well-differentiated mucinous adenocarcinoma.

Gallbladder cancer, management of early tumors.

In spite of the fatal course associated with patients with gallbladder cancer, there is a subgroup of them in whom prognosis could be improved. Although early gallbladder cancer is considered a tumor with invasion of the mucosa or the muscular layer, in this manuscript we analyze those with invasion confined to the gallbladder. Pre-operative diagnosis of these patients is rare with cholecystectomy specimen histologic analysis being the most common way of detecting these tumors. The level of wall invasion represents a useful and practical way of dividing the patients according to their prognosis and treatment. Mucosal and muscular invasion tumors could be cured by simple cholecystectomy. Among patients with a tumor confined to the gallbladder, those with subserosal infiltration represent the largest group. Residual tumor after cholecystectomy is a common fact in these patients, thus a more aggressive procedure than simple cholecystectomy should be performed. Generally, extended cholecystectomy is the preferred approach for dealing with these patients. Unfortunately, in spite of the employment of extended and potentially curative surgery, prognosis is still poor and additional therapeutic procedures are needed. Finally, when tumors compromise the serosal layer, 5-year survival is poor irrespective of the type of therapy. However, well-selected cases deserve to undergo aggressive treatment.

Gallbladder cancer in a high risk area: morphological features and spread patterns.

BACKGROUND/AIMS: Gallbladder carcinoma is one of the most frequent malignant tumors in Chile. The aim of this paper is to show our experiences in gallbladder carcinoma. METHODOLOGY: Six-hundred-sixty-nine cases of gallbladder carcinoma were included in this prospective study; 557 females (83.5%) and 112 males (16.5%). In 466 cases (70%), diagnosis was carried out in the cholecystectomy sample, 45 cases were partial cholecystectomies and 158 cases were metastases of gallbladder carcinoma. RESULTS: Ninety-eight per cent of the cases were adenocarcinomas, and in 85% of the cases gallstones were observed. Thirty-seven per cent of the primary tumors were macroscopically inapparent. One-hundred-thirty-one cases (29%) were early carcinomas and 323 cases (71%) were advanced carcinomas. A relationship between differentiation grade and infiltration level (p=0.0001) was observed. Lymph-node metastasis was found in 18.5%, 4.5% and 3.3% in the first, second and third lymph-node barriers respectively. Muscular tumors presented no lymph-node metastasis, while in serosal tumors lymph node metastasis reached 62% (p=0.04). Hepatic tumor infiltration was observed in 11%, 19% and 38% of muscular, subserosal and serosal tumors. CONCLUSIONS: The high frequency of inapparent carcinomas, gallstones and inflammatory changes of the vesicular wall are elements that make the pre-operative diagnosis of gallbladder carcinoma difficult. Differentiation grade and infiltration level are the most reliable prognostic factors in gallbladder carcinoma. Lymph-node metastasis or liver tumor infiltration are infrequent in early gallbladder carcinoma.

[Nucleolar organizer region in bladder cancer. Relationship with histologic grade, stage, and prognosis]. / Región del organizador nucleolar en el cáncer vesical. Relación con grado histológico, estado y pronóstico.

By means of silver staining, 31 transitional bladder cancer were studied in order to quantify the number of the nucleolar organizer regions and ist relationship with histological grade, tumoral stage and prognosis of the disease. The group under study was composed by 18 cases superficial carcinomas (T1 stage), and 13 deep carcinomas (T2 and T3b stage). A significant difference between normal and neoplastic bladder mucosa, and between T1 and t3b stage was demonstrated (p = 0.03). However, ther was not difference between patients whom develop recurrences. In this study we were not able to demonstrate the importance of the count of the nucleolar organizer regions as prognostic factor in bladder cancer.

[Cancer of the prostate: evaluation of the expression of the mutated protein of the 53 tumor suppressor gene]. / Cáncer de la próstata: evaluación de la expresión de la proteína mutada del gen supresor de tumores p53.

UNLABELLED: Prostate cancer is the most common tumour in men, and is most frequently established late in life. The objective of the article is to determine the protein expression of gene p53 in prostate cancer and to correlate the findings with clinical, morphological and epidemiological parameters. MATERIAL AND METHODS: Immunohistochemical techniques with monoclonal antibody used to study the gene p53 expression. The study included 35 prostate carcinoma: 4 cases in stage A; 5 cases in stage B; 12 in stage C and 14 in stage D. The control group consisted in 10 benign prostate hyperplasia. Average age was 66.8 (SD +/- 6.7 years). RESULTS: Positive staining for gene p53 protein was seen in 11 of the 35 cases (31.4%). All stage A and B tumours were negative; however, stage C and D tumours were positive in 16 and 64% cases respectively. In the control group all cases were gene p53 negative. No statistical relationship was seen between Gleason Index and positive results for p53. There was a significant difference between gene 53 expression and clinical stage. CONCLUSIONS: Results show that the immunohistochemical expression of gen p53 mutated protein keeps no relation to Gleason's rating index and is seen with significantly higher frequency in advanced, primarily stage D tumours.

Bacteriophage performance against Staphylococcus aureus in milk is improved by high hydrostatic pressure treatments.

The combined effect of bacteriophages, vB_SauS-phi-IPLA35 (phiIPLA35) and vB_SauS-phi-IPLA88 (phiIPLA88), and high hydrostatic pressure (HHP) on Staphylococcus aureus Sa9 was evaluated in pasteurized whole milk under a simulated cold chain break, which was simulated by incubation of milk at 25°C for 48 h. Four-hundred MPa was found to be the most suitable pressure to be used in combination with these phages. Two different levels of staphylococcal initial contamination (1×10(4) and 1×10(6) CFU/mL) were tested. A synergistic effect between HHP and phages was observed in both cases. Compared to each single treatment, the combined treatment was able to reduce the initial S. aureus contamination below the detection limit (<10 CFU/mL). Bacteriophage performance in pressurize milk against S. aureus enabled milder hydrostatic pressure treatments, therefore phages can be regarded as a valuable hurdle on minimally processed food.

[The sea blue histiocyte syndrome: a case report]. / Sindrome del histiocito azul marino: caso clínico.

A young pregnant woman presented with splenomegaly and a hemorrhagic syndrome. A persistent alteration of several coagulation tests was demonstrated. Large foamy pigmented macrophages were shown by bone marrow aspiration. The histopathologic findings are consistent with the sea blue histiocyte syndrome, a benign type of lipid storage disease.

[Malignant histiocytosis in children]. / Histiocitosis maligna en el niño.

A case of malignant histiocytosis in a two year old boy is reported. His main clinical features were fever, lymphadenopathy, hepatomegaly and splenomegaly. Lymph node biopsy showed a sinusoidal type of lymph node infiltration, histiocytes of malignant aspect and erythrophagocytosis. Liver infiltration with tumoral cells was demonstrated by needle biopsy. The clinical evolution was rapidly progressive and after six months of chemotherapy he died of intercurrent respiratory infection.

[Gallbladder cancer: a review]. / Cáncer de la vesícula biliar. Algunas consideraciones.

In Chile, gallbladder cancer is the tumor with the highest mortality rates among women. Cholelithiasis is the most common associated factor and the reduction in cholecystectomy rates could be an important factor in the incidence of gallbladder cancer. Unfortunately, the disease is diagnosed late and the study of the surgical piece is the main form of early recognition. The degree of gallbladder wall infiltration by the tumor is the simplest and best staging method that has prognostic value. Gallbladder fat must be considered as a separate tissue, since its biological behavior differs from that of the subserous. The treatment of these tumors is based in their dissemination modality that is mainly local and regional. Surgical resection and radiotherapy are potentially effective. However the detection of high risk patients that should be subjected to cholecystectomy should be the better therapeutic alternative.

[Determination of DNA content in salivary gland tumors]. / Determinación del contenido de ADN en tumores de glándulas salivales.

BACKGROUND: DNA content determination is a useful tool in the characterization of different malignant tumors. AIM: To measure DNA content in cells of salivary gland tumors as adjunct to histological diagnosis, correlating morphologic and biological features of these tumors. MATERIAL AND METHODS: From the archives of the Pathology service of a general hospital, 21 salivary gland tumors, 15 pleomorphic adenomas, 3 mucoepidermoid carcinomas and 3 cystic adenoid carcinomas were selected. DNA content was determined in the histological samples using a flow cytometric DNA analysis. RESULTS: All pleomorphic adenomas had a normal or diploid DNA content. Fifty percent of malignant tumors had an aneuploid DNA content (1 mucoepidermoid carcinoma and 2 cystic adenoid carcinomas). CONCLUSIONS: DNA determination may help in the histological diagnosis of salivary gland tumors. The presence of aneuploidy suggests malignity.