Quantitative bone SPECT analysis of mandibular condyles in an asymptomatic population: an approach to normal reference values.

Bone scintigraphy is an extremely valuable technique in diagnosis and treatment planning for patients with condylar hyperplasia (CH). The main objective of this study was to develop an approach to determine normal activity values in the mandibular condyles, adjusted to age and sex, through quantitative analysis of bone single-photon emission computed tomography (SPECT) on a condyle-by-condyle basis and to compare these values with those of a control group comprising patients with confirmed CH. Technetium 99 m-methylene diphosphonate (99mTc-MDP) SPECT studies of the mandibular condyles were performed in patients with no mandibular pathology for quantitative analysis. Regions of interest were drawn on slices representing the upper, middle, and inferior thirds of each condyle and on the summation of transaxial slices representing the whole condyle (three-dimensional approach). The clivus was used for internal validation and the condyle to clivus ratios were calculated. These ratios were compared between 'normal' and 'diseased' condyles. A total 144 condyles in normal patients and 25 in confirmed CH patients were analysed. Differences between the ratios were evaluated through the coefficient of variation. In normal patients, the ratios to the clivus on the summed condyle image showed the lowest variability: range 0.3-1.28 (median 0.74). The quantile regression model showed significant differences with respect to sex, but not to age. The Mann-Whitney test showed significant differences in the ratios to clivus between normal and diseased condyles (P<0.0001).

Hexane abatement and spore emission control in a fungal biofilter-photoreactor hybrid unit.

The performance of a fungal perlite-based biofilter coupled to a post-treatment photoreactor was evaluated over 234 days in terms of n-hexane removal, emission and deactivation of fungal spores. The biofilter and photoreactor were operated at gas residence times of 1.20 and 0.14min, respectively, and a hexane loading rate of 115±5gm(-3)h(-1). Steady n-hexane elimination capacities of 30-40gm(-3)h(-1) were achieved, concomitantly with pollutant mineralization efficiencies of 60-90%. No significant influence of biofilter irrigation frequency or irrigation nitrogen concentration on hexane abatement was recorded. Photolysis did not support an efficient hexane post-treatment likely due to the short EBRT applied in the photoreactor, while overall hexane removal and mineralization enhancements of 25% were recorded when the irradiated photoreactor was packed with ZnO-impregnated perlite. However, a rapid catalyst deactivation was observed, which required a periodic reactivation every 48h. Biofilter irrigation every 3 days supported fungal spore emissions at concentrations ranging from 2.4×10(3) to 9.0×10(4)CFUm(-3). Finally, spore deactivation efficiencies of ≈98% were recorded for the photolytic and photocatalytic post-treatment processes. This study confirmed the potential of photo-assisted post-treatment processes to mitigate the emission of hazardous fungal spores and boost the abatement performance of biotechnologies.

Variabilidad del gen de la envoltura del VIH-1 en tres grupos humanos con diferentes conductas sexuales de riesgo para adquirir ITS-VIH / Envelope genetic variability of HIV-1 infecting human groups with differents risk sexual behaviour to adquire HIV-STD

Objetivo: Determinar la variabilidad genética del gen de la envoltura porción C2-V3-C3 (env) del VIH-1 infectando grupos humanos con diferente conducta sexual de riesgo para adquirir ITS-VIH. Materiales y métodos: Se seleccionaron 50 sujetos infectados con VIH-1 de los cuales 19 fueron hombres trabajadores sexuales (HTS), 8 mujeres trabajadoras sexuales (MTS) y 23 sujetos heterosexuales (SH). Se realizó la extracción de ADN genómico y la amplificación del gen env por PCR. Se identificó el subtipo genético por ensayo de movilidad de heterodúplex (HMA) y se confirmaron los resultados por análisis filogenético. Asimismo, se realizó el análisis de recombinación intragenética, diversidad y distancia genética en las tres poblaciones. Resultados: Se amplificó el gen env en 49 muestras (98 per cent) y se logró secuenciar el fragmento en 40 de ellas. Se observó que el 97,5 per cent de las muestras de VIH fueron subtipo B mientras que una muestra no pudo ser clasificada filogenéticamente. Asimismo, se encontraron pequeños tramos de recombinación en el gen env de VIH en MTS (33 per cent), HTS (43 per cent) y SH (45 per cent). El mayor índice de diversidad de nucleótidos (Pi) de env se encontró entre las muestras de VIH provenientes de SH y HTS (0,12 y 0,13 respectivamente). Conclusiones: Se encontró una mayor variabilidad genética del gen env de VIH-1 en las poblaciones de HTS y SH, sin embargo, el subtipo genético y la frecuencia de recombinación de este fragmento genético fue similar en los tres grupos estudiados.

Objectives: To determine the genetic variability of C2-V3-C3 envelope genetic portion (env) of HIV-1 from human groups showing different sexual behavior to acquire STD/HIV. Material and methods: Fifty HIV-infected subjects were selected, which nineteen of them were male sex workers (MSW), eight female sex workers (FSW), and twenty three heterosexual subjects (HS). DNA genomic was extracted and the gen env was amplified by PCR. Genetic subtype as identified by heteroduplex mobility assay (HMA) and confirmed by phylogeny. Likewise, intragenic recombination, diversity and genetic distance were analyzed for the three populations. Results: Forty nine (98 per cent) samples were successfully amplified by PCR but only forty were sequenced. HMA and phylogeny analysis revealed that 97.5 per cent of HIV-1 samples were subtype B, but only one sample remain unclassifiable. Likewise, short recombinant regions in gene env were found from FSW (33 per cent), MSW (43 per cent) and HS (45 per cent). Finally, HIV species infecting MSW and HS showed the highest diversity nucleotide between them (Pi) (0,12 and 0,13 respectively). Conclusion: This study revealed that env gene was highly variable in MSW and HS populations, however genetic subtype and recombination frequency were similar for the three groups.

Expresión de proteínas del choque térmico HSP72 y HSP73 en casos colombianos de Linfoma de Hodgkin positivos y negativos para virus de Epstein Barr / Expression of heat shock proteins HSP72 and HSP73 in Epstein-Barr positive or negative Hodgkin lymphoma

Background: The expression of heat shock proteins (HSP70) in tumor cells or virus infected cells is important for the induction of specific cellular immune response. They are implicated in transport of immunodominants peptides in the endoplasmic reticulum, activation of antigen presenting cells and cross priming of CD8 T cells. Aim: To analyze the expression of HSP70 protein in its constitutive (HSP73) and inducible forms (HSP72) in Hodgkin's lymphoma (HL), infected or not by Epstein Barr virus (EBV) and to assess its relationship with pathological subtype, clinical stages and treatment response. Material and methods: The analysis of HSP73 and HSP72 was done by immunoperoxidase on routinely processed paraffin sections with prior antigen retrieval. Results: Sixty seven cases were studied. The expression of HSP73 and HSP72 was detected in 19.4 and 17.9% of samples respectively. The infiltrating lymphocytes expressed HSP72 in 58% of cases. The pathological subtypes with the higher expression in lymphocytes were mixed cellularity and nodular sclerosis. No differences in HSP70 expression were observed, according to clinical stage, treatment response or the presence of EBV. Conclusions: The expression of HSP72 on lymphocytes suggests that this protein plays an important role in the induction and amplification of anti-tumor immune response (Rev Méd Chile 2003; 131: 1375-81).

[Focal atrophy with stellate scars in children with chronic gastritis associated to Helicobacter pylori. Is this early atrophic gastritis?]. / Atrofia focal con "cicatrices estrelladas" en niños con gastritis crónica asociada con Helicobacter pylori. Gastritis atrófica inicial?

BACKGROUND: Atrophic gastritis has not been described in children in the setting of Helicobacter Pylori infection. METHODS: Gastric biopsies of six children (7 to 11 years old) with history of HpCG and recent therapeutic eradication of H. Pylori, were reviewed. In the 6 H. Pylori was documented with histology, culture, direct visualization and/or serology before treatment. Cases were compared with five biopsies of age-matched patients showing none of the above-mentioned clinical data. All the biopsies were formalin-fixed, paraffin embedded and stained with hematoxilin-eosin, Masson trichrome and reticulin stain. RESULTS: The biopsies of the six treated patients showed variable-in-size stellate-shaped spots of glandular loss replaced by dense connective tissue with few inflammatory cells. The fibrous tissue showed a central area of scarring and radially oriented spikes extending to adjacent interglandular tissue, more evident with the Masson trichrome stain. Density of inflammatory cells in the lamina propria was variable. H. Pylori organisms were consistently absent. On the reticulin stain the atrophic areas showed coarser and compacted reticulin. Stellate scars were not present in the five controls. CONCLUSIONS: Small foci with fibrous scars may be found in children with long standing HpCG, perhaps as an early sequel of it. We hypothesize that if the chronic gastritis-gastric atrophy process is a continuum, these stellate scars may be representing the very beginning of the multifocal atrophic gastritis usually seen in adult patients.

BCG diseminada tipo miliar. Hallazgo de autopsia y diagnostico por PCR / Miliary BCG. Autopsy finding and PCR diagnosis

La diseminacion del BCG es una complicacion conocida en pacientes inmunodeficientes en quienes produce lesiones cutaneas oseas y viscerales, con extenso daño tisular. Menos frecuentemente se la ha mencionado en pacientes inmunocompetentes; en estos ultimos produce lesiones locales, diseminacion cutanea y osea, y una forma de diseminacion miliar visceral principalmente pulmonar y hepatica(cinco casos publicados previamente)

Atypical plasmacytoid monomorphic adenoma of salivary glands of the tongue: cytologic, histologic, immunohistochemical, and ultrastructural findings.

We describe the case of an 11-yr-old boy with a 2.5-cm-diameter soft tumor superficially located at the dorsal aspect of the tongue. Fine-needle aspiration cytology smears showed plump epithelioid cells with round to mildly oval nuclei and open chromatin. One or two nucleoli of intermediate size were noticed in each nucleus. These cells appeared singly or in small groups. The findings were interpreted as containing plasmacytoid cells coming from an adenoma of salivary gland origin. The histologic examination of the surgical specimen revealed noncohesive, pleomorphic polygonal cells combining plasmacytoid/rhabdoid cytoplasmic features, with mild to moderate nuclear pleomorphism. One mitotic figure was observed per 10 high-power fields. Immunoreactivity was strongly positive for vimentin and S-100 protein, less intense for the cytokeratins, and negative for smooth muscle actin, muscle-specific actin, myoglobin, and GFAP. No ultrastructural evidences of myogenous differentiation were found. We propose that this case represents an unusual atypical variant of plasmacytoid monomorphic adenoma.

Histopathologic findings in the lymphoid and reticuloendothelial system in pediatric HIV infection: a postmortem study.

The present report describes the histopathological features of lymphoreticular tissues in 29 pediatric autopsies of human immunodeficiency virus (HIV)-infected patients. Mean age for the whole group was 1.77 years; 68.9% and 62% of the cases were 2 years old or less and 1 year old or less at the time of death, respectively. Twenty-one cases were categorized as acquired immunodeficiency syndrome (AIDS) and the rest included seven HIV-positive newborns and infants and two infants belonging to a high-risk group. The thymus (24 cases) showed severe lymphoid depletion (atrophy) in 16 (66.6%) cases, microcystic transformation of Hassall's corpuscles (HCs) in 4, calcified HCs in 3, absence of HCs in 3, and plasmacytic infiltrates and Warthin-Finkeldey-type multinucleated giant cells (also found in lymph nodes and bowel lymphoid aggregates in the same case) in 1. Lymph nodes (25 cases) revealed extensive lymphocyte depletion (68%); selective follicular (2 cases) or paracortical (3 cases) atrophy; hemophagocytosis (44%); some type of hyperplasia (plasmacytosis, enlarged follicles) in 5 cases; some type of lymphadenitis (12 cases), 5 cases of which were due to opportunistic infections (cytomegalovirus, 2; histoplasmosis, cryptococcosis, Mycobacterium avium-intracellulare, 1 each). Main findings in the spleen (28 cases) were extensive lymphocyte depletion (10 cases), limited to the white pulp in 4 and including the red pulp in 7; some type of lymphoid hyperplasia (limited to white pulp in 6 cases and involving the red pulp in 5); hemophagocytosis (7 cases); and foci exhibiting a peculiar arrangement of spindle-shaped cells combined with capillaries, plasma cells, and occasionally siderophages in 11. These we have termed kaposiform areas due to the resemblance to the so-called inflammatory variant of Kaposi's sarcoma. This pattern was also recognized in lymph nodes of two cases. Although atrophy was the main theme, cases with hyperplasia were also noticed. The possible relationship, if it exists at all, between kaposiform areas and Kaposi's sarcoma remains to be established. No tumor was found in this series. No specific histopathologic pattern of lymphoid tissues atributable to HIV emerged form this study aside from kaposiform areas, a microscopic feature not previously reported in this circumstance in pediatrics.

Opportunistic infections in pediatric HIV infection: a study of 74 autopsy cases from Latin America. The Latin American AIDS Pathology Study Group.

The present report describes opportunistic infections found at 74 autopsies of pediatric HIV/AIDS patients performed at several hospitals in Latin American countries. Fungal infections were the most common (53 cases), Candida sp. (39.18%) and Pneumocystis carinii (20.27%) being the most frequently recognized. Other fungal diseases included histoplasmosis, aspergillosis, and cryptococcosis. Viral infections were present in 31 cases, 38.7% being due to cytomegalovirus. Other viruses recognized included herpes simplex and adenovirus. Additional opportunistic infections were due to Mycobacterium avium-intracellulare, toxoplasmosis, and tuberculosis. Nonspecific bacterial bronchopneumonia was present in 11 cases. Cytomegalovirus and P. carinii coinfection was the most common association found. In this series patients died at a younger age (72% at or younger than 1 year old) and there was a slightly higher number of cases of histoplasmosis and brain toxoplasmosis than in other previously published series of infants and children.

[Pathologic findings in diethylene glycol poisoning]. / Hallazgos patológicos en la intoxicación por dietilenglicol.

We are reporting the necropsy findings of 7 patients poisoned with diethylene glycol-contaminated propolis (a rubbery substance produced by bees from vegetal resins). Besides the well-known features of hydropic necrosis of centrolobular areas in the liver and renal tubules we found acute pancreatitis with diffuse enzymatic fat necrosis which in two of the cases was considered the secondary cause of death, and acute demyelinating lesions in the central and peripheral nervous system. Six out of the 7 cases showed glomerular PAS-positive arteriolar hyalinosis at the vascular pole, in two of them widely disseminated. Differing from the findings reported in ethylene glycol poisoning we could not find calcium oxalate crystals in any of the cases. The pancreatic, central and peripheral nervous system lesions as well as the glomerular arteriolar hyalinosis have not been previously described in the literature in relation with diethylene glycol poisoning.

Sindrome de mobius por lesiones de tronco cerebral en un lactante con defectos congénitos multiples. Hallazgos neuropatológicos / Mobius syndrome due to brain stem damage in a milk-fed baby with multiple congenital defects. Neuropathological findings

Se presenta un caso de síndrome de mobius caracterizado clínicamente por parálisis facial y paresia del velo del paladar y cuerdas vocales del lado derecho, congénitos, asociados a hipoplasia ósea de la hemicara derecha y trastornos de conducción cardíacos (bloqueo de rama derecha y hemibloqueo anterior izquierdo). El estudio neuropatológico reveló una hipoplasia del hemibulbo y hemiprotuberancia derechos con ausencia de los núcleos del facial y del núcleo ambiguo. Se halló además ausencia del 1er. par, hipoplasia del núcleo del 6to. derecho y ausencia del núcleo del fasículo solitario. En el corazón se encontró una comunicación tipo ostium primun y anormalidades microscópicas del haz de his y sus ramas. El conjunto malformativo sugiere el efecto de una noxa que actuó entre la 5ta. y 6ta. semanas de edad gestacional (aproximadamente día 38 de la gestación), indicando una patogenia disruptiva para este caso. La revisión de la literatura reveló que si bien el síndrome de mobius puede tener además otras etiologías (genética esporádica, genética familiar, hipóxica periparto) su estudio neuroanatómico no es un hecho muy frecuente.

Biventricular hypoplasia with myocardial fiber hypertrophy and disarray.

An 8-year-old girl with a long history of cardiac disease had restrictive filling of both ventricles, severe atrioventricular valve regurgitation, and extreme dilation of both atria. At necropsy the inflow areas of both ventricles were small, and part of the left ventricle lacked compact myocardium. Histology revealed myofiber hypertrophy and focal dysplasia (disarray) in both ventricles. The findings suggest an abnormality of cardiac development that occurred before gestation week 5.

Cytologic characteristics of Wilms' tumors in fine needle aspirates. A study of ten cases.

The cytologic findings observed in fine needle aspiration (FNA) biopsy smears from ten cases of Wilms' tumor are reported. Blastemal cells, small, round cells with slightly oval nucleoli and fine, evenly dispersed chromatin, were recognized in all cases. Stromal (90%) and epithelial components (40%) were also present. Additional recognizable features were anaplasia (in two of three cases having histologic anaplasia), rosettes (four cases), necrosis (six cases) and inflammatory cells (six cases). In six cases, small fragments of tissue were also recovered for histologic examination after paraffin embedding. There were no complications attributable to the procedure. FNA cytology may be used as the sole diagnostic procedure for Wilms' tumors when preoperative chemotherapy protocols are in use.

Rhabdomyomatous dysplasia of the lung.

This article deals with the presence of nontumoral striated muscle fibers in the lungs of 3 neonates. These cells were diffusely distributed in one lung (case 1) or in both (case 2), or focally localized to the lung parenchyma adjacent to the liver in a case with a large right diaphragmatic hernia (case 3). The striated muscle fibers were located in the walls of small bronchi and bronchioli or in the alveolar interstitium. Other major lung malformations found simultaneously were absence of lobation, hypoplastic lungs, and hypoplastic pulmonary vessels. The origin of striated muscle fibers in the neonatal lung has been attributed to anomalous differentiation of mesoblastic cells (as in cases 1 and 2). The presence of striated muscle cells in the lower margin of a hypoplastic lung associated with a right diaphragmatic hernia (case 3) suggests that intrapulmonary inclusion of diaphragmatic muscle fibers might be a source as well. Striated muscle fibers in the lung are commonly associated with major malformations involving heart and lungs, suggesting a much wider morphogenetic error.