A hot-Jupiter progenitor on a super-eccentric retrograde orbit.

Giant exoplanets orbiting close to their host stars are unlikely to have formed in their present configurations1. These 'hot Jupiter' planets are instead thought to have migrated inward from beyond the ice line and several viable migration channels have been proposed, including eccentricity excitation through angular-momentum exchange with a third body followed by tidally driven orbital circularization2,3. The discovery of the extremely eccentric (e = 0.93) giant exoplanet HD 80606 b (ref. 4) provided observational evidence that hot Jupiters may have formed through this high-eccentricity tidal-migration pathway5. However, no similar hot-Jupiter progenitors have been found and simulations predict that one factor affecting the efficacy of this mechanism is exoplanet mass, as low-mass planets are more likely to be tidally disrupted during periastron passage6-8. Here we present spectroscopic and photometric observations of TIC 241249530 b, a high-mass, transiting warm Jupiter with an extreme orbital eccentricity of e = 0.94. The orbit of TIC 241249530 b is consistent with a history of eccentricity oscillations and a future tidal circularization trajectory. Our analysis of the mass and eccentricity distributions of the transiting-warm-Jupiter population further reveals a correlation between high mass and high eccentricity.

GATA-3 is a proto-oncogene in T-cell lymphoproliferative neoplasms.

Neoplasms originating from thymic T-cell progenitors and post-thymic mature T-cell subsets account for a minority of lymphoproliferative neoplasms. These T-cell derived neoplasms, while molecularly and genetically heterogeneous, exploit transcription factors and signaling pathways that are critically important in normal T-cell biology, including those implicated in antigen-, costimulatory-, and cytokine-receptor signaling. The transcription factor GATA-3 regulates the growth and proliferation of both immature and mature T cells and has recently been implicated in T-cell neoplasms, including the most common mature T-cell lymphoma observed in much of the Western world. Here we show that GATA-3 is a proto-oncogene across the spectrum of T-cell neoplasms, including those derived from T-cell progenitors and their mature progeny, and further define the transcriptional programs that are GATA-3 dependent, which include therapeutically targetable gene products. The discovery that p300-dependent acetylation regulates GATA-3 mediated transcription by attenuating DNA binding has novel therapeutic implications. As most patients afflicted with GATA-3 driven T-cell neoplasms will succumb to their disease within a few years of diagnosis, these findings suggest opportunities to improve outcomes for these patients.

Genomic landscape of lung cancer in the young.

Background: Lung cancer in the young is a rare entity of great interest due to the high frequency of targetable mutations. In this study, we explored the genomic landscape of non-small cell lung cancer (NSCLC) in young patients and compared it with genetic alterations in older patients. Methods: Comparative study of the genomic profile of NSCLC young (≤40 years old) vs older patients (>40 years old) from Instituto Nacional de Enfermedades Neoplásicas (INEN) in Lima, Peru. Archival paraffin-embedded tumor samples were profiled with FoundationOne CDx assay to identify short variants alterations (insertions and deletions), copy number variations (CNV), tumor mutational burden and microsatellite instability in 324 driver genes and rearrangements in 28 commonly rearranged genes. A targetable alteration was defined as any alteration in a driver oncogene for which an FDA approved therapy existed at the time of study enrollment. Results: Overall, 62 tumors were profiled, 32 from young and 30 from older patients. All clinicopathological features (smoking status, clinical stage, and histology) were similar between groups, except for gender (65.6% of females in the younger group vs 40% in the older group, P=0.043). At least one actionable mutation was present in 84.4% and 83.3% in younger and older patients, respectively. Alteration rates in the main genes were: BRAF, 3.1%(n=1) vs 0%; EGFR, 46.9% (n=15) vs 43.3% (n=13); ERBB2, 12.5% (n=4) vs 16.7% (n=5); KRAS, 15.6% (n=5) vs 16.7% (n=5); ALK, 6.3% (n=2) vs 3.3% (n=1); RET, 0.0% vs 3.3% (n=1); ROS1, 3.1% (n=1) vs 3.3% (n=1); NTRK1, 0.0% vs 3.3% (n=1) and MET, 3.1% (n=1) vs 13.3% (n=4). Mean TMB was 4.04 Mut/Mb (SD ± 3.98) for young vs 8.06 Mut/Mb (SD ± 9.84) for older patients (P=0.016). There were not significant differences in CNV, frequency of gene rearrangements, or microsatellites instability. Conclusion: NSCLC in the young in our cohort was characterized by a high frequency of actionable genetic aberrations and a low TMB, which was also true for our older patients. The enrichment of actionable mutations in young patients described in other reports might be attributed to differences in the etiology and clinicopathological characteristics between younger and older patients and therefore not be applicable to all populations.

Notch Signaling Promotes Mature T-Cell Lymphomagenesis.

Peripheral T-cell lymphomas (PTCL) are agressive lymphomas that develop from mature T cells. The most common PTCLs are genetically, molecularly, and clinically diverse and are generally associated with dismal outcomes. While Notch signaling plays a critically important role in both the development of immature T cells and their malignant transformation, its role in PTCL is poorly understood, despite the increasingly appreciated function of Notch in regulating the proliferation and differentiation of mature T cells. Here, we demonstrate that Notch receptors and their Delta-like family ligands (DLL1/DLL4) play a pathogenic role in PTCL. Notch1 activation was observed in common PTCL subtypes, including PTCL-not otherwise specified (NOS). In a large cohort of PTCL-NOS biopsies, Notch1 activation was significantly associated with surrogate markers of proliferation. Complementary genetically engineered mouse models and spontaneous PTCL models were used to functionally examine the role of Notch signaling, and Notch1/Notch2 blockade and pan-Notch blockade using dominant-negative MAML significantly impaired the proliferation of malignant T cells and PTCL progression in these models. Treatment with DLL1/DLL4 blocking antibodies established that Notch signaling is ligand-dependent. Together, these findings reveal a role for ligand-dependent Notch signaling in driving peripheral T-cell lymphomagenesis. SIGNIFICANCE: This work demonstrates that ligand-dependent Notch activation promotes the growth and proliferation of mature T-cell lymphomas, providing new therapeutic strategies for this group of aggressive lymphomas.

Collision tumour of large-cell neuroendocrine carcinoma and adenocarcinoma in the stomach: A case report.

Concurrence of adenocarcinoma and large-cell neuroendocrine carcinoma of the stomach is a rare condition. Here, we report a case of gastric collision tumour with large-cell neuroendocrine carcinoma and adenocarcinoma. A 71-year-old Peruvian man presented with nausea, epigastric pain, and weight loss for seven months. An Endoscopic evaluation revealed a huge ulcerative and infiltrative mass in the upper and middle third of the stomach. The patient underwent a D2 total gastrectomy. Microscopically, two separated and attached ulcerative lesions were recognised. The proximal to the cardial lesion showed neuroendocrine morphology and immunoreactivity for synaptophysin, and the other a moderated tubular adenocarcinoma Borrmann type III. Both lesions invaded serosa and lymph nodes metastases were found in 17 of 41 lymph nodes retrieved (one lymph node with neuroendocrine metastatic deposits).

[Management of pancreatic cystic tumors in the Alberto Sabogal Sologuren hospital]. / Manejo de tumores quísticos del páncreas en el hospital Alberto Sabogal Sologuren.

INTRODUCTION: Cystic tumors of the pancreas comprise 1% of all neoplasms of the pancreas and 10 to 15% of pancreatic cysts. There are a variety of cystic lesions, of which 90% is made up of serous cystadenomas, mucinous cystic neoplasms, intraductal mucinous neoplasms and solid pseudopapillary neoplasms. MATERIALS AND METHODS: This study describes and analyzes retrospectively the clinical, radiological, surgical, pathological and follow up of 12 patients operated on for cystic tumors of the pancreas in the hospital IV Alberto Sabogal Sologuren, in the period 2005 to 2010. RESULTS: we found 5 (41%) serous cystadenomas with a mean age of 66 years, localized 80% in the head and 20% body; 2 (17%) mucinous cystic neoplasms with a mean age of 54, all located in body, 2 (17%) intraductal mucinous neoplasms with a mean age of 63, all located in the head, and 3 (25%) solid pseudopapillary neoplasms with a mean age of 33 years, located in body 33% and 66% in tail with a predominance of females in a ratio of 3:1. Had abdominal pain (75%), weight loss (17%) and palpable mass (17%). Of the 2 cystic mucinous neoplasms, only one have a low-grade dysplasia, of the two mucinous intraductal neoplasms, one have grade moderate dysplasia and the other with a high degree, the rest of cystic neoplasms were benign. We realize 6 Pancreaticoduodenectomy, 4 corporocaudales pancreatectomies, 2 distal pancreatectomies; of them splenectomy realize in 4 patients (2 in corporocaudal pancreatectomies and 2 distal pancreatectomies). In all cases the preoperative diagnosis was based on abdominal TEM. in 4 patients was expanded with RMN for suspicion of mucinous tumor and in 2 patients was performed CPRE for suspected intraductal tumors. Two patients coursed with atelectasis, and one patient had pancreatic fistula grade A and other mild pancreatitis post-operative. No patient was reoperated. There was no mortality post operative. Postoperative was more for the pancreaticoduodenectomy group. In a 2 year follow up, no observed recurrence and all patients are alive. CONCLUSION: Preoperative diagnosis is crucial given the differences in natural history of the spectrum of lesions. Despite improved radiographic imaging, techniques, definitive diagnosis is only made after studying the resection sample.

Histological survey of Pacific oysters Crassostrea gigas (Thunberg) in Galicia (NW Spain).

In Galicia, there is an increasingly interest among representatives of the oyster industry in the development of Pacific oyster Crassostrea gigas culture. Nevertheless severe mortalities and emerging health problems in this species have been recently reported in European farming areas. A histological survey was performed from 2004 to 2009 to assess health status in both cultured and wild Galician oysters. Different symbiotic organisms and conditions were detected, including viral gametocytic hypertrophy (VGH) which is reported here for first time in Spanish coast. VGH, prokaryote-like colonies and ciliates were observed in oyster tissues without causing host damage. A haplosporidian infection, copepods inducing lesions and a cellular proliferative disorder were detected in some samples causing moderate host damage; their low prevalence suggests these parasites are not a threat for C. gigas in Galicia. None of the parasites detected is OIE (Office International des Epizooties: the World Organization for Animal Health) notifiable. Although the current study did not identify any pathogens or diseases of concern, it provides important prevalence baseline data for future health and epidemiological assessments needed to better understanding the existing and emerging health problems in this species.

Manejo de tumores quísticos del páncreas en el Hospital Alberto Sabogal Sologuren / Management of cystic tumors of the pancreas in the Hospital Alberto Sabogal Sologuren

INTRODUCCIÓN: Los tumores quísticos del páncreas comprenden el 1 % de todas las neoplasias del páncreas y el 10 al 15% de los quistes pancreáticos. Existe una gran variedad de lesiones quísticas, de ellos el 90% está constituido por cistoadenomas serosos, neoplasias mucinosas quísticas, neoplasias intraductales mucinosas y las neoplasias sólido pseudopapilares. MATERIALES Y MÉTODOS: El presente estudio describe y analiza en forma retrospectiva las características clínicas, radiológicas, quirúrgicas, patológicas y de seguimiento de 12 pacientes operados por tumores quísticos del páncreas en el hospital IV Alberto Sabogal Sologuren, en el periodo 2005 al 2010. RESULTADOS: Se encontraron 5 (41%) cistoadenomas serosos con una edad media de 66 años, localizándose 80% en cabeza y 20% en cuerpo; 2 (17%) neoplasias mucinosas quísticas con una edad media de 54 años, todas localizadas en cuerpo; 2 (17%) neoplasias intraductales mucinosas con una edad media de 63 años, todas localizadas en cabeza, y 3 (25%) neoplasias sólido pseudopapilares con una edad media de 33 años, ubicadas 33% en cuerpo y 66% en cola, con predominancia del sexo femenino en una relación de 3:1. Presentaron dolor abdominal (75%), baja de peso (17%) y masa palpable (17%). De las 2 neoplasias mucinosas quísticas, solo uno presentó displasia de bajo grado, de las 2 neoplasias intraductales mucinosas 1 resultó con displasia de grado moderado y otra de alto grado, el resto de neoplasias quísticas resultaron benignas. Se realizaron 6 pancreatoduodenectomías, 4 pancreatectomías corporocaudales, 2 pancreatectomías distales; de ellas se realizó esplenectomía en 4 pacientes (2 en pancreatectomías corporocaudal y 2 pancreatectomías distales). En todos los casos el diagnóstico preoperatorio se basó en TEM abdominal, en 4 pacientes se amplió con RMN por sospecha de tumor mucinoso y en 2 se realizó CPRE por sospecha de tumores intraductales. ...

INTRODUCTION: Cystic tumors of the pancreas comprise 1% of all neoplasms of the pancreas and 10 to 15% of pancreatic cysts. There are variety of cystic lesions, of which 90% is made up of serous cystadenomas, mucinous cystic neoplasms, intraductal mucinous neoplasms and solid pseudopapillary neoplasms. MATERIALS AND METHODS: This study describes and analyzes retrospectively the clinical, radiological, surgical, pathological and follow up of 12 patients operated on for cystic tumors of the pancreas in the hospital IV Alberto Sabogal Sologuren, in the period 2005 to 2010. RESULTS: We found 5 (41%) serous cystadenomas with a mean age of 66 years, localized 80% in the head and 20% body; 2 (17%) mucinous cystic neoplasms with a mean age of 54, all located in the head, and 3 (25%) solid pseudopapillary neoplasms with a mean age of 33 years, located in body 33% and 66% in tail with a predominance of females in a ratio of 3:1. Had abdominal pain (75%), weight loss (17%) and palpable mass (17%). Of the 2 cystic mucinous neoplasms, only one have a low-grade dysplasia, of the two mucinous intraductal neoplasms, one have grade moderate dysplasia and the other with a high dregree, the rest of cystic neoplasms were beningn. We realize 6 Pancreaticoduodenectomy, 4 corporocaudales pancreatectomies. 2 distal pancreatectomies; of them splenectomy realize in 4 patients (2 in corporocaudal pancreatectomies and 2 distal pancreatectomies). In all cases the preoperative diagnosis aws based on abdominal TEM. in 4 patients was expanded with RMN for suspicion of mucinous tumor and in 2 patients was performed CPRE for suspected intraductal tumors. Two patients coursed with atelectasis, and one patiernt had pancreatic fistula grande A and other mild pancreatitis post-operative. No patient was reoperated. There was no mortality post operative. Postoperative was more for the pancreaticoduodenectomy group. In a 2 year folow up, no oberved recurrence and alla patients are alive. ...

Factores pronósticos de sobrevida en pacientes con cáncer de endometrio tratados con radioterapia preoperatoria / Prognostic factors for survival in patients with endometrial cancer treated with preoperative radiotherapy

Objetivo: determinar la sobrevida global (SG), los factores pronósticos de sobrevida libre de enfermedad y SG, el porcentaje de complicaciones en pacientes con cáncer de endometrio tratados con radioterapia preoperatoria en el INEN. Material y Métodos: se realizó un estudio retrospectivo analítico de 381 historias clínicas de pacientes con cáncer de endometrio entre 1995 a diciembre del 2004, 53 pacientes cumplieron con los criterios de inclusión: estadiaje clínico I, II, III según FIGO 1971, radioterapia externa (RTE) a la pelvis a dosis de 50Gy a 50,4Gy en 25-28 sesiones más Braquiterapia (BT) seguido de cirugía. Resultados: la dosis promedio de BT fue 45Gy (rango 25Gy a 70Gy) administradas en una sola aplicación de baja tasa de dosis. La sobrevida Global (SG) a los 5 años fue 86,39%. La sobrevida diferenciada por estadios clínicos fue 85,71%, 83,52% y 84,03% para los estadíos I, II y III respectivamente sin diferencia significativa (p=0,55). El 20,75% (11/53) fallecieron por enfermedad, de las cuales 36,36% (4/11) recurrieron a nivel loco regional y 63,64% (7/11) metástasis a distancia. El análisis Bivariado no demostró factores de riesgo asociados con la mortalidad. Sin embargo el análisis multivariado de Regresión de Cox solo la enfermedad extra-pélvica es un factor de mal pronóstico y se relacionó con mayor mortalidad [HR: 5,27 IC 95% (1,10-25,28)] (p=0,038). Las pacientes con viabilidad en la pieza quirúrgica recibieron mayor dosis de radiación al punto A (mayores a 90Gy) que las piezas quirúrgicas no viables (p=0,041). El porcentaje de complicaciones fue del 20,75% (11/53) siendo el 9,44% (5/53) complicaciones severas (grado 4). Conclusiones: La presencia de enfermedad extra-pélvica fue un factor de mal pronóstico para la sobrevida. Palabras Claves: cáncer endometrial, radioterapia preoperatoria, sobrevida global.

Objective: To determine overall survival (OS), prognostic factors for disease-free survival and OS, the percentage of complications in patients with endometrial cancer treated with preoperative radiotherapy at the Instituto Nacional de Enfermedades Neoplásicas (INEN). Material and Methods: An analytical retrospective study of 381 patient records with endometrial cancer between 1995 and December 2004 was done; Only 53 patients full filed the inclusion criteria: clinical stage I, II, III according to FIGO 1971, external beam radiation to the pelvis to a dose of 50Gy - 50.4Gy in 25-28 sessions followed Brachytherapy (BT) and then surgery. Results: The mean dose of BT was 45Gy (range 25Gy to 70Gy) administered in a single application with low dose radiation. The OS at 5 years was 86.39%. OS for clinical stages I, II and III were 85.71%, 83.52% and 84.03% respectively, with no significant difference (p=0.55). 20.75% (11/53) died of disease, of which 36.36% (4/11) had recurrence in the pelvis and 63.64% (7/11) was distant metastases. Bivariate analysis showed no risk factors associated with mortality. However in the multivariate Cox regression only the extra-pelvic disease is a poor prognostic factor and was associated with increased mortality [HR: 5.27 IC 95% (1.10-25.28)] (p=0.038). The patients with viability in the surgical specimen had higher radiation doses to point A than non-viable surgical specimens (greater than 90Gy) difference that was significant (p = 0.041). The complication rate was 20.75% (11/53) and 9.44% (5/53) of complications were grade 4. Conclusions: The presence of extra-pelvic disease proved to be a poor prognostic factor for overall survival. Keywords: endometrial cancer, preoperative radiotherapy, overall survival.

[Impact of splenectomy and/or distal pancreatectomy in the prognosis of the proximal gastric cancer]. / Impacto de la esplenectomia y/o pancreatectomia distal en el pronostico del cancer gastrico proximal.

OBJECTIVES: Identify prognostic factors associated to total or proximal gastrectomy with or without splenectomy and / or distal pancreatectomy in patient with proximal gastric cancer. Evaluate the frequency of lymph node metastasis to the hilum and splenic artery, postoperative morbidity and mortality and the impact of lymphadenectomy of group 10 and 11 on long term survival. MATERIALS AND METHODS: We performed an observational, descriptive, longitudinal and retrospective study analyzing patients with diagnostic of proximal third gastric adenocarcinoma subjected to total or proximal gastrectomy with or without splenectomy or distal pancreatectomy in the service of Abdomen of the Instituto Nacional de Enfermedades Neoplásicas between 1990 and 2005. Overall survival for each of the groups was calculated using the Kaplan-Meier method, prognostic factors were evaluated using univariate and multivariate analysis. RESULTS: We studied 219 patients with proximal third gastric adenocarcinoma (cardias and bottom), of wich, according to inclusion criteria, only qualify 129 (N=129): 22 (17.1%) were treated by gastrectomy alone, 79 (61.2%) gastrectomy associated witch splenectomy and 28 (21.7%) gastrectomy with distal pancreatosplenectomy, constituting three treatment groups. We compared the survival of each group and each factor analyzed, determining the following prognostic factors: lymph node metastasis (N2-N3), degree of differentiation, undifferentiated tumors and Borrmann III and IV tumors. Neither splenectomy or distal pancreatectosplenectomy improved survival compared to the gastrectomy alone. The morbidity and mortality was higher in patients with more aggressive but more aggressive surgery without significant value. CONCLUSIONS: The number of nodes removed in patients who had pancreatosplenectomy and /or splenectomy was higher, however, had no impact on survival at 5 years.

Impacto de la esplenectomia y/o pancreatectomia distal en el pronóstico del cáncer gástrico proximal / Impact of splenectomy and / or distal pancreatectomy in the proximal gastric cancer prognosis

OBJETIVOS: Identificar factores pronósticos asociados a gastrectomías totales o proximales con o sin esplenectomía y/o pancreatectomía distal en pacientes con cáncer gástrico proximal. Evaluar la frecuencia de metástasis ganglionar en el hilio y arteria esplénica, la morbimortalidad postoperatoria y el impacto de la linfadenectomía del grupo 10 y 11 en la sobrevida del paciente. MATERIALES Y METODOS: Es un estudio observacional, descriptivo, longitudinal y retrospectivo que analiza pacientes con diagnóstico de adenocarcinoma gástrico del tercio proximal sometidos a gastrectomía total y/o proximal asociada o no a esplenectomía y/o pancreatectomía distal, en el Departamento de Abdomen del Instituto Nacional de Enfermedades Neoplásicas entre 1990 y 2005. La sobrevida global para cada uno de los grupos fue calculada utilizando, el método de Kaplan-Meier, los factores pronósticos fueron evaluados utilizando el análisis univariado y multivariado de Cox. RESULTADOS: Fueron estudiados 219 pacientes con adenocarcinoma gástrico del tercio proximal (cardias y fondo), de los cuales, según los criterios de inclusión, califican solo 129 (N= 129): 22 (17.1%) se trataron mediante gastrectomía sola, 79 (61.2%) gastrectomía asociada a esplenectomía y 28 (21.7%) gastrectomía con pancreatoesplenectomía distal, constituyendo tres grupos de tratamiento. Se comparó la supervivencia de cada grupo y en cada factor analizado, determinando los siguientes factores pronósticos: compromiso ganglionar (N2 ûN3), grado histológico indiferenciado y tumores Borrmann III y IV. Ni la esplenectomía ni la pancreatoesplenectomía distal mejoró la supervivencia con respecto a la gastrectomía sola. La morbimortalidad fue mayor en los pacientes con cirugía más agresiva pero sin valor significativo. CONCLUSIONES: El número de ganglios extirpados en pacientes que tuvieron pancreatoesplenectomía y/o esplenectomía fue mayor, sin embargo, no tuvo impacto en la sobrevida a 5 años.

OBJECTIVES: Identify prognostic factors associated to total or proximal gastrectomy with or without splenectomy and / or distal pancreatectomy in patient with proximal gastric cancer. Evaluate the frequency of lymph node metastasis to the hilum and splenic artery, postoperative morbidity and mortality and the impact of lymphadenectomy of group 10 and 11 on long term survival. MATERIALS AND METHODS: We performed an observational, descriptive, longitudinal and retrospective study analyzing patients with diagnostic of proximal third gastric adenocarcinoma subjected to total or proximal gastrectomy with or without splenectomy or distal pancreatectomy in the service of Abdomen of the Instituto Nacional de Enfermedades Neoplásicas between 1990 and 2005. Overall survival for each of the groups was calculated using the Kaplan-Meier method, prognostic factors were evaluated using univariate and multivariate analysis. RESULTS: We studied 219 patients with proximal third gastric adenocarcinoma (cardias and bottom), of wich, according to inclusion criteria, only qualify 129 (N=129): 22 (17.1%) were treated by gastrectomy alone, 79 (61.2%) gastrectomy associated witch splenectomy and 28 (21.7%) gastrectomy with distal pancreatosplenectomy, constituting three treatment groups. We compared the survival of each group and each factor analyzed, determining the following prognostic factors: lymph node metastasis (N2-N3), degree of differentiation, undifferentiated tumors and Borrmann III and IV tumors. Neither splenectomy or distal pancreatectosplenectomy improved survival compared to the gastrectomy alone. The morbidity and mortality was higher in patients with more aggressive but more aggressive surgery without significant value. CONCLUSIONS: The number of nodes removed in patients who had pancreatosplenectomy and /or splenectomy was higher, however, had no impact on survival at 5 years.

Epstein-Barr virus-positive systemic NK/T-cell lymphomas in children: report of six cases.

AIMS: The World Health Organization lymphoma classification recognizes two different Epstein-Barr virus (EBV)-positive T-cell lymphoproliferative disorders of childhood: systemic EBV-positive T-cell lymphoproliferative disease of childhood, and hydroa vacciniforme-like lymphoma, which is more prevalent in Asia and Latin America. The aim of this study was to characterize six cases of paediatric EBV-positive peripheral T-cell lymphoma with distinct features. METHODS AND RESULTS: All cases were male, with a median patient age of 9 years (range: 5-17 years). Most of them presented suddenly with fever, weight loss, hepatosplenomegaly, peripheral lymphadenopathy, and high lactate dehydrogenase (LDH) levels. Moreover, gut, lung or soft tissues of the abdominal wall were also affected in four cases. Partial to total replacement of the lymph node by pleomorphic infiltration of atypical neoplastic cells was found in all cases. Vasculitis and geographical areas of necrosis were seen in three and four cases, respectively. Neoplastic cells showed expression of EBV-encoded RNA, T-cell markers (CD2 and CD3), and cytotoxic markers (TIA1, granzyme-B, and perforin). CD56 and T-cell receptor -γ were expressed in one case each. TCR-BF1, CD4, CD8 and anaplastic lymphoma kinase were negative. In all cases, the disease progressed rapidly, causing death of the patient, with a median survival of 7.1 months (range: 1-13 months). CONCLUSIONS: These cases probably represent a solid form of systemic EBV-positive T-cell lymphoproliferative disease of childhood, which requires identification and the development of appropriate therapy.

EBV-associated cutaneous NK/T-cell lymphoma: review of a series of 14 cases from peru in children and young adults.

We have reviewed clinically, morphologically, and immunophenotypically a series of 14 Epstein-Bar virus (EBV)+ cutaneous natural killer cell (NK)/T-cell lymphoma from Peru. Most (11 out of 14) of these cases fit well into the category of Hydroa vacciniforme-like lymphoma (HVLL), but 3 have a different clinical presentation, without facial involvement. In all 14 cases, skin lesions present in both the sun-exposed and nonexposed areas exhibited a slowly progressive relapsing course, changing from edema, to blistering, ulceration, and final scarring. The immunophenotype had a cytotoxic T or NK-cell lineage. The mean time of disease before admission to hospital was 69 months (range, 6 mo to 31 y). Only 2 patients had fever, hepatosplenomegaly, systemic lymphadenopathy, and a high lactate dehydrodenage (LDH) level at the time of diagnosis, whereas 10 had facial swelling. After treatment, only 4 patients remain alive, although with persistent disease. Ten patients died after a mean follow-up of 11.6 months after the initial diagnosis (range, 1 to 32 mo), because of concurrent infections (4 cases), disease progression (4 patients) or both (2 patients). Endemic Epstein-Bar virus (EBV)-positive cutaneous NK/T-cell lymphoproliferative disorders in childhood and early adulthood are characterized by a protracted clinical course, eventually leading to an aggressive phase characterized by concurrent infections and disease progression.

Comparison of diagnostic techniques to detect the clam pathogen Perkinsus olseni.

Perkinsosis in clams in Galicia (NW Spain) is caused by the protozoan parasite Perkinsus olseni Lester & Davis, 1981. We used 5 clam species of commercial interest cultured in Galicia (Ruditapes decussatus, R. philippinarum, Venerupis pullastra, V. rhomboides, and Donax trunculus) to compare various P. olseni diagnostic techniques. Results of a nested PCR assay for the diagnosis of P. olseni were compared to those obtained using 2 classical methods of diagnosis proposed by the World Organisation for Animal Health (OIE), viz. histology and incubation in Ray's fluid thioglycollate medium (RFTM). Moreover, the same samples were analyzed by 2 separate research groups. The results obtained by PCR showed high sensitivity and good correlation between research groups. In addition, this method is faster than histopathology and incubation on RFTM and less expensive than histopathology. Moreover, nested PCR requires less specialized training for technicians than histology. Histopathology also showed high specificity and a good correlation between research groups. Results from incubation on RFTM suggest that this method could give divergent results between research groups, particularly in the case of low levels of infection, but it is nevertheless useful for disease-monitoring purposes. PCR is appropriate for rapidly screening large numbers of clams.

Inhibitory activity of Phaeobacter strains against aquaculture pathogenic bacteria.

A total of 523 bacterial strains were isolated during a 4-year period from mollusc hatcheries (flat oyster and clams) in Galicia (NW Spain). All of the strains were tested for their antibacterial activity against three larval pathogens (Vibrio anguillarum USC-72, V. neptunius PP-145.98, and Vibrio sp. PP-203). Of the isolates, 52 inhibited at least one of the target strains, and 11 inhibited all of them. The main source of active strains was oyster larvae, followed by water, tank surfaces, spat, and broodstock. Four similar strains, belonging to the genus Phaeobacter, showed the strongest activity. Strain PP-154, selected as representative of this group, displayed a wide spectrum of inhibitory activity against aquaculture pathogens, especially against members of the genus Vibrio, which is responsible for the most larval deaths. The inhibitory ability of such strain on solid medium was confirmed in seawater experiments, and the optimal conditions for antibacterial activity were established. These strains are promising probiotics for aquaculture facilities. Their potential benefit is based on the capacity to control the proliferation of a variety of aquaculture bacterial pathogens in mollusc larval cultures.

Inhibitory activity of Phaeobacter strains against aquaculture pathogenic bacteria

A total of 523 bacterial strains were isolated during a 4-year period from mollusc hatcheries (flat oyster and clams) in Galicia (NW Spain). All of the strains were tested for their antibacterial activity against three larval pathogens (Vibrio anguillarum USC-72, V. neptunius PP-145.98, and Vibrio sp. PP-203). Of the isolates, 52 inhibited at least one of the target strains, and 11 inhibited all of them. The main source of active strains was oyster larvae, followed by water, tank surfaces, spat, and broodstock. Four similar strains, belonging to the genus Phaeobacter, showed the strongest activity. Strain PP-154, selected as representative of this group, displayed a wide spectrum of inhibitory activity against aquaculture pathogens, especially against members of the genus Vibrio, which is responsible for the most larval deaths. The inhibitory ability of such strain on solid medium was confirmed in seawater experiments, and the optimal conditions for antibacterial activity were established. These strains are promising probiotics for aquaculture facilities. Their potential benefit is based on the capacity to control the proliferation of a variety of aquaculture bacterial pathogens in mollusc larval cultures (AU)

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Ultrastructural developmental cycle of Haplosporidium montforti (phylum Haplosporidia) in its farmed abalone host, Haliotis tuberculata (Gastropoda).

The sequential developmental cycle of Haplosporidium montforti, a recently described species from farmed abalone Haliotis tuberculata (Gastropoda), was studied. Ornamented and operculated mature spores were electron dense. The nucleus of the uninucleated free cell divided successively, giving rise to multinucleate plasmodia, containing up to 100-120 nuclei. Later, the plasmodia developed into sporonts inside sporocysts with irregular contours. Each of their nuclei gave rise to uninucleate sporoblasts. At the next phase of development, a very irregular membranous group of cisternae began to differentiate in the cytoplasm of each sporoblast, surrounding each nucleus and the adjacent cytoplasm. Each sporoblast differentiated into a spore. This process was characterized by the appearance of dense blisters of amorphous material at the periphery that gradually formed the prespore wall and pre-operculum. Simultaneously, in the endosporoplasm, the spherulosome and several haplosporosomes were formed. During the final phase of the maturation process, the spores became gradually denser, and the endosporoplasmic structures were barely visible.

Ultrastructural description of new Rickettsia-like organisms in the commercial abalone Haliotis tuberculata (Gastropoda: Haliotidae) from the NW of Spain.

Rickettsia-like organisms (RLOs) were found in the commercially farmed abalone Haliotis tuberculata in the northwestern region of the Atlantic Coast of Spain and are described from light and transmission electron microscopy observations. The RLOs measured approximately 1.6 x 0.9 microm and were found in intracytoplasmic, spherical to ellipsoidal vacuoles (up to 8 microm) in the epithelial cells of the digestive diverticulae. The morphological ultrastructure of these organisms was typically prokaryotic, including a plasmalemma and a thin Gram-negative type cell wall. Several ultrastructural changes were observed in the epithelial cells of the host containing the RLOs. The nuclei became pycnotic and several basophilic dense inclusions appeared in the cytoplasm. In addition, the host cell appeared lysed and was ruptured in advanced stages of infection. It was impossible to ascertain whether the RLOs are responsible for this disease, as a haplosporidian infection was also present. We can only conclude that the presence of RLOs simultaneously with a haplosporidian parasite may contribute to the mortality of the abalone host.

Occurrence of the haemocyte parasite Bonamia sp. in flat oysters Ostrea puelchana farmed in San Antonio Bay (Argentina).

Culture of native flat oysters Ostrea puelchana d'Orbigny in San Antonio Bay (San Matías Gulf, Argentina) began in 1995. After elevated mortality (33%) occurred in September 1996, 18 mo after immersion, histopathological analysis and evaluation of parasitic prevalence was carried out. In October 1997, after 31 mo of cultivation, cumulative mortality was 80%, and in December of the same year, when individuals reached marketable size, mortality was 95% and culture was discontinued. The present study describes the haemocytic parasitism that affected O. puelchana, and suggests that a Bonamia sp. was the etiological agent. This parasite should be considered as a different species from Bonamia sp. detected in Australia and New Zealand until more studies are made to determine the correct taxonomy. This work constitutes the first record of this haemocyte parasite in flat oysters from the Argentinean coast.