Metástasis de carcinoma de células en anillo de sello al cuello uterino / Metastasis of signet-ring cell carcinoma of the cervix

Las metástasis de carcinomas extragenitales al útero es rara y el compromiso al cuello uterino es excepcional, especialmente del tipo histológico de carcinoma de células en anillo de sello. Se presentan tres casos encontrados en 240 adenocarcinomas cervicales (1,25 por ciento) diagnosticados entre 1979-2012. Dos casos se presentaron en pacientes de 48 y 56 años originados en carcinomas lobulillares infiltrantes de la mama diagnosticados previamente. La primera paciente está viva a 19 meses del diagnóstico ginecológico y la segunda falleció a los 14 meses, siendo en ambas un hallazgo histológico incidental en cirugías realizadas por patología ginecológica benigna. El tercer caso se presentó en una paciente de 43 años que debutó por metrorragia y tumor cervical y fue originado en un carcinoma gástrico infiltrante difuso, encontrado en forma sincrónica y fallece a los 2 meses del diagnóstico. Se revisan los criterios diagnósticos entre metástasis y carcinoma primario de células en anillo de sello del cuello uterino y el aporte al diagnóstico de la histología convencional, la inmunohistoquímica y la tipificación molecular de HPV. Conclusión: Se concluye que la metástasis de carcinoma de células en anillo al cuello uterino es rara y el pronóstico es malo. La citoreducción y la quimioterapia podría tener un rol para casos seleccionados de carcinomas metastásicos de origen mamario y que estos casos no deberían ser considerados un evento preterminal.

The uterine metastatic involving of extragenital carcinomas is rare, especially the signetring cell type. Three of such a cases were found in 240 cases of adenocarcinomas of uterine cervix (1.25 percent) diagnosed between 1979-2012. Two of these cases occurred in patients aged 48 and 56 years with infiltrating lobular carcinomas arising in the breast previously diagnosed. The first patient is alive at 19 months after diagnosis and the second is deceased at 14 months after diagnosis. In both cases, the metastasis to the cervix was an incidental histological finding in surgeries performed by benign gynecological pathology. The third case was identified in a 43-years old patient who debuted with metrorrhagia and cervical tumor which was originated in a diffuse infiltrating gastric carcinoma that was found synchronously and she is dead at 2 months after diagnosis. The diagnostic criteria between metastases and primary cervix carcinoma of signet ring cells and the contribution to the diagnosis of conventional histology, immunohistochemistry and molecular typing of HPV are reviewed. The metastasis of signet ring cell carcinoma to the uterine cervix is rare and the survival is poor. Conclusion: The role of cytoreduction and chemotherapy for selected cases of metastasis from breast carcinomas should be considered and in such a case the gynecological involvement should not be considered a preterminal event.

Ictericia obstructiva secundaria a tumor de células granulares de la vía biliar extrahepática / Obstuctive jaundice secondary to extrahepatic bile ducts granular cell tumor

Bile ducts granular cell tumor is a rare entity. Of neural origin, mostly benign, may, however, present mimicking malignancy. We report a 32 years old female presenting with painless jaundice and extrahepatic bile ducts stenosis confirmed with MRC. Extrahepatic bile ducts resection is performed. Reconstruction involves four independent ducts to a Roux en Y enteric loop. She has a good postoperative outcome, with no evidence of complications nor recurrence at 17 months of follow up.

El tumor de células granulares en la vía biliar es una neoplasia rara de origen neural, en su mayoría benigna y cuya presentación puede sugerir patología maligna. Objetivo: Se presenta el caso clínico, características anatomopatológicas, manejo y evolución de una paciente joven que se presenta con ictericia obstructiva por estenosis subcarinal biliar. Paciente y Método: Paciente 32 años, sexo femenino, con ictericia, coluria y prurito. Diagnóstico de estenosis biliar y dilatación de vía biliar intrahepática se confirma con colangiorresonancia magnética. Se realiza resección de vía biliar extrahepática desde supracarinal que incluye vía biliar distal. Reconstitución bilioentérica a Y de Roux que involucra cuatro conductos intrahepáticos. Evoluciona en forma satisfactoria en el postoperatorio. El seguimiento alejado a 17 meses revela una satisfactoria condición de la paciente, sin signos de complicación o recidiva. Conclusión: El manejo por un equipo de experiencia multidisciplinario nos permitió ayudar a una paciente con rara patología, benigna en lo histológico, pero que puede representar un gran desafío técnico.

Protective effect of parvalbumin on excitotoxic motor neuron death.

The mechanism responsible for the selective vulnerability of motor neurons in amyotrophic lateral sclerosis (ALS) is poorly understood. Several lines of evidence indicate that susceptibility of motor neurons to Ca(2+) overload induced by excitotoxic stimuli is involved. In this study, we investigated whether the high density of Ca(2+)-permeable AMPA receptors on motor neurons gives rise to higher Ca(2+) transients in motor neurons compared to dorsal horn neurons. Dorsal horn neurons were chosen as controls as these cells do not degenerate in ALS. In cultured spinal motor neurons, the rise of the cytosolic Ca(2+) concentration induced by kainic acid (KA) and mediated by the AMPA receptor was almost twice as high as in spinal neurons from the dorsal horn. Furthermore, we investigated whether increasing the motor neuron's cytosolic Ca(2+)-buffering capacity protects them from excitotoxic death. To obtain motor neurons with increased Ca(2+) buffering capacity, we generated transgenic mice overexpressing parvalbumin (PV). These mice have no apparent phenotype. PV overexpression was present in the central nervous system, kidney, thymus, and spleen. Motor neurons from these transgenic mice expressed PV in culture and were partially protected from KA-induced death as compared to those isolated from nontransgenic littermates. PV overexpression also attenuated KA-induced Ca(2+) transients, but not those induced by depolarization. We conclude that the high density of Ca(2+)-permeable AMPA receptors on the motor neuron's surface results in high Ca(2+) transients upon stimulation and that the low cytosolic Ca(2+)-buffering capacity of motor neurons may contribute to the selective vulnerability of these cells in ALS. Overexpression of a high-affinity Ca(2+) buffer such as PV protects the motor neuron from excitotoxicity and this protective effect depends upon the mode of Ca(2+) entry into the cell.

Ca(2+)-permeable AMPA receptors and selective vulnerability of motor neurons.

To evaluate the role of excitotoxicity in the pathogenesis of amyotrophic lateral sclerosis (ALS), we compared the sensitivity of motor neurons and that of dorsal horn neurons to kainic acid (KA). Short exposure to KA resulted in the death of motor neurons, while dorsal horn neurons were unaffected. This selective motor neuron death was completely dependent on extracellular Ca(2+) and insensitive to inhibitors of voltage-operated Ca(2+) or Na(+) channels. It was also completely inhibited by the specific AMPA antagonist LY300164 and by Joro spider toxin (JSTx), a selective blocker of AMPA receptors that lack the edited GluR2 subunit. KA selectively killed those motor neurons that stained positive for the Co(2+) histochemical staining, a measure for the presence of Ca(2+)-permeable AMPA receptors. These results suggest that Ca(2+) entry via Ca(2+)-permeable AMPA receptors is responsible for the selective motor neuron death. As the Ca(2+) permeability of the AMPA receptor is regulated by its GluR2 subunit, we stained motor neurons for GluR2. Immunoreactivity was present in all motor neurons, albeit to a variable degree. However, double-staining experiments demonstrated that motor neurons clearly expressing GluR2, also expressed Ca(2+)-permeable AMPA receptors. This indicates that despite the abundant expression of GluR2, this subunit is excluded from a subset of AMPA receptors and that the activation of these receptors is responsible for the selective motor neuron death.

Efficacy and tolerance of three different calcium acetate formulations in hemodialysis patients.

BACKGROUND: Calcium acetate (CaAc) is an effective phosphate binder in patients with chronic renal failure. However, an important side effect is gastro-intestinal discomfort. Phos-ex (Cablon, The Netherlands) is the only commercially available non-coated CaAc formulation in our country. We developed two new CaAc formulations: neutral-coated CaAc (NCCaAc) and enteric-coated CaAc (ECCaAc). METHODS: In a randomised double-blinded cross-over trial we compared efficacy and tolerance of the three formulations in 19 stable hemodialysis patients, with a mean age of 63 years (range, 36-85), who had been on hemodialysis for 19 months (range, 6-47). Patients were randomised to receive NCCaAc or ECCaAc, with meals, for a period of 10 weeks and after cross-over for another 10 weeks. During a third non-blinded period, patients received Phos-ex for 10 weeks. RESULTS: Serum phosphate was significantly higher with ECCaAc compared to NCCaAc (1.89 +/- 0.07 vs. 1.70 +/- 0.08 mmol/l, P < 0.05). Serum Ca was significantly lower with ECCaAc compared to NCCaAc or Phos-ex (2.38 +/- 0.04, 2.47 +/- 0.04 and 2.48 +/- 0.04 mmol/l, P < 0.05). There were less hypercalcemic and more hyperphosphatemic events in the ECCaAc period, compared to the other periods. The daily CaAc dose and dietary intake of calcium, phosphate, protein and calories were comparable in all three periods. With Phos-ex, patients noticed more gastro-intestinal complaints than with to NCCaAc and ECCaAc. Two patients stopped taking Phos-ex because of side effects. CONCLUSIONS: In hemodialysis patients, phosphate control and tolerance were both influenced by the formulation of CaAc. Although phosphate control was adequate with all three formulations of CaAc, ECCaAc was less effective compared to NCCaAc or Phos-ex. NCCaAc and ECCaAc were better tolerated than Phos-ex. Regarding efficacy and tolerance, NCCaAc was the best calcium acetate formulation.

Mutational changes in physiochemical cell surface properties of plant-growth-stimulating Pseudomonas spp. do not influence the attachment properties of the cells.

Bacteriophage-resistant mutant strains of the root-colonizing Pseudomonas strains WCS358 and WCS374 lack the O-antigenic side chain of the lipopolysaccharide, as was shown by the loss of the typical lipopolysaccharide ladder pattern after analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. These strains differed from their parent strains in cell surface hydrophobicity and in cell surface charge. The observed variation in these physicochemical characteristics could be explained by the differences in sugar composition. The mutant strains had no altered properties of adherence to sterile potato roots compared with their parental strains, nor were differences observed in the firm adhesion to hydrophilic, lipophilic, negatively charged, or positively charged artificial surfaces. These results show that neither physicochemical cell surface properties nor the presence of the O-antigenic side chain plays a major role in the firm adhesion of these bacterial cells to solid surfaces, including potato roots.

Insecticide residues in the Tuttle Creek Reservoir Ecosystem, Kansas-1970-71.

Various components of the aquatic ecosystem of Tuttle Creek Reservoir on the Big Blue River in northeastern Kansas were examined for organochlorine insecticide residues in 1970-71. Components examined were water, sediments, periphyton, zooplankton, insects, and whole-body samples of 10 common fish species. Only dieldrin and sigmaDDT residues were detected. Dieldrin was found in part of the nonfish samples at levels ranging up to 0.01 ppm and in 97 percent of the fish samples with a high level of 0.17 ppm. SigmaDDT residues were also detected in part of the nonfish samples at levels ranging up to 0.42 ppm, and in 98 percent of the fish samples at levels as high as 0.57 ppm. Authors' findings are roughly similar to those of other surveys of Kansas fishes. All levels are relatively low compared with those reported in surveys from other parts of the Nation.