Estudio histoquímico e inmunotipificación de poblaciones leucocitarias del timo de alpacas (Vicugna pacos) menores a 60 días de edad

The objective of the study was to identify leukocyte populations in the postnatal thymus of alpacas under 60 days of age. Euthanasia was performed on six Huacaya alpacas in Huanta province, Ayacucho, Peru. Thymus samples were obtained, embedded in OCT and immediately frozen in liquid nitrogen and stored at -70 ºC until processing. Frozen sections were prepared and mounted with organosilane. Immunohistochemistry was performed with mouse primary antibody and rabbit secondary antibodies. The reaction was evidenced using the avidin-biotin-peroxidase complex and was counter-stained with hematoxylin. Specific monoclonal antibodies were used for the identification of leukocytic subpopulations of the thymus. Five visual fields were randomly evaluated at 400X. The distribution and density of the staining was classified as negative (-), inconstant (±), slight (+), moderate (++) and strong (+++). The results show that the largest population of leukocyte cells was located in the cortex of the thymus and corresponded to immature cells that do not express surface markers; likewise, the highest population of immunomarked cells, in maturation, were located in the medulla of the thymus, predominantly the TCR-αβ lymphocytes, with low values ​​of γδ TCR lymphocytes, CD8 lymphocytes, B lymphocytes and monocytes/macrophages, with inconstant lymphocyte values CD4. In the cortex of the thymus there were low values ​​of αβ TCR lymphocytes and CD8 lymphocytes, and inconstant values ​​of monocytes/macrophages, without evidence of γδ TCR lymphocytes, CD4 lymphocytes and B lymphocytes.El objetivo del estudio fue identificar las poblaciones leucocitarias en el timo posnatal de alpacas menores de 60 días de edad. Se realizó la eutanasia a seis alpacas Huacaya en la provincia de Huanta, Ayacucho, Perú. Se obtuvieron muestras de timo que fueron embebidas en OTC y congeladas inmediatamente en nitrógeno líquido y conservadas a -70 ºC hasta su procesamiento. Se prepararon secciones congeladas y se fijaron a la lámina con el adhesivo organosilano. Se realizó la inmunohistoquímica con anticuerpo primario de ratón y secundarios de conejo. La reacción se evidenció empleando el complejo avidina-biotina-peroxidasa y se contra-coloreó con Hematoxilina. Se emplearon anticuerpos monoclonales específicos para la identificación de las subpoblaciones leucocíticas del timo; se evaluaron cinco campos visuales de forma aleatoria a un aumento de 400X. La distribución y densidad de la tinción se clasificó como negativa (-), inconstante (±), ligera (+), moderada (++) y fuerte (+++). Los resultados muestran que la mayor población de células leucocitarias se ubicó en la corteza del timo y correspondieron a células inmaduras que no expresan marcadores de superficie; así mismo, la mayor población de células inmunomarcadas, en maduración, se ubicaron en la médula del timo, predominando los linfocitos TCR αβ, con valores bajos de linfocitos TCR γδ, linfocitos CD8, linfocitos B y monocitos/macrófagos, con valores inconstantes de linfocitos CD4. En la corteza del timo se observaron valores bajos de linfocitos TCR αβ y linfocitos CD8, y valores inconstantes de monocitos/macrófagos, sin evidencias de linfocitos TCR γδ, linfocitos CD4 y linfocitos B

Phase I study of TP300 in patients with advanced solid tumors with pharmacokinetic, pharmacogenetic and pharmacodynamic analyses

Background: A Phase I dose escalation first in man study assessed maximum tolerated dose (MTD), dose-limiting toxicity (DLT) and recommended Phase II dose of TP300, a water soluble prodrug of the Topo-1 inhibitor TP3076, and active metabolite, TP3011. <p/>Methods: Eligible patients with refractory advanced solid tumors, adequate performance status, haematologic, renal, and hepatic function. TP300 was given as a 1-hour i.v. infusion 3-weekly and pharmacokinetic (PK) profiles of TP300, TP3076 and TP3011 were analysed. Polymorphisms in CYP2D6, AOX1 and UGT1A1 were studied and DNA strand-breaks measured in peripheral blood mononuclear cells (PBMCs). <p/>Results: 32 patients received TP300 at 1, 2, 4, 6, 8, 10, 12 mg/m2. MTD was 10 mg/m2; DLTs at 12 (2/4 patients) and 10 mg/m2 (3/12) included thrombocytopenia and febrile neutropenia; diarrhea was uncommon. Six patients (five had received irinotecan), had stable disease for 1.5-5 months. TP3076 showed dose proportionality in AUC and Cmax from 1--10 mg/m2. Genetic polymorphisms had no apparent influence on exposure. DNA strand-breaks were detected after TP300 infusion. <p/>Conclusions: TP300 had predictable hematologic toxicity, and diarrhea was uncommon. AUC at MTD is substantially greater than for SN38. TP3076 and TP3011 are equi-potent with SN38, suggesting a PK advantage

BIOPSIA SIN ASPIRACIÓN CON AGUJA FINA ECOGUIADA TRANSABDOMINAL EN EL DIAGNÓSTICO DE NEOPLASIAS PROSTÁTICAS EN CANINOS

Fine-needle aspiration biopsy guided with trans-abdominal ultrasound is a safe and minimally invasive technique that is used to confirm the diagnosis of prostatic neoplasia. A variation of this technique is a fine-needle biopsy without aspiration in which negative pressure is not exerted when obtaining the material. Four cases with clinical and ultrasound alterations compatible with prostatic neoplasia were evaluated with ultrasound-guided fine-needle biopsy without aspiration as a diagnostic tool. The procedure was done with conventional ultrasound guidance. When the area of interest was found, an ultrasoundguided sample collection was performed using a 21G x 1½” needle. The sample was expelled through the needle with a syringe onto a glass slide and stained using Tinción 15®. Sample interpretation was based on the identification of tumor cells and general criteria of malignancy. Ultrasound-guided fine-needle biopsy without aspiration as a diagnostic tool allowed obtaining sufficient quantity of biological material with minimal blood contamination and formation of artifacts, and appropriate conservation of cellular morphology to perform suitable interpretation and cytological diagnosis of prostatic neoplasia.La biopsia por aspiración con aguja fina ecoguiada transabdominal es una técnica segura y mínimamente invasiva utilizada para confirmar el diagnóstico de neoplasia prostática. Una variación de esta técnica es la biopsia sin aspiración con aguja fina (BSAAF) donde no se ejerce presión negativa para obtener el material. Cuatro casos con alteraciones clínicas y ultrasonográficas compatibles con neoplasia prostática fueron evaluados con la técnica BSAAF ecoguiada. El procedimiento fue realizado con la guía de un ultrasonógrafo convencional. En las áreas de interés para la colección de la muestra ecoguiada se hizo una punción con aguja 21G x 1½”. Las muestras fueron expelidas de la aguja con una jeringa sobre una lámina de vidrio y teñidas con Tinción 15®. La interpretación de las muestras estuvo basada en los criterios de identificación de células neoplásicas. La técnica BSAAF ecoguiada permitió obtener suficiente cantidad de material biológico con una mínima contaminación de sangre, mínima formación de artefactos, y una apropiada conservación de la morfología celular para realizar una adecuada interpretación y diagnóstico citológico de neoplasias prostáticas

The MRI central vein marker: differentiating PPMS from RRMS and ischaemic SVD

© 2018 The Author(s). Objective To determine whether the assessment of brain white matter lesion (WML) central veins differentiate patients with primary progressive MS (PPMS) from relapsing-remitting MS (RRMS) and ischemic small vessel disease (SVD) using 3T MRI. Methods In this cross-sectional study, 71 patients with PPMS, RRMS, and SVD were imaged using a T2∗-weighted sequence. Two blinded raters identified the total number of WMLs, proportion of WMLs in periventricular, deep white matter (DWM) and juxtacortical regions, and proportion of WMLs with central veins in all patient groups. The proportions were compared between disease groups, including effect sizes. MS or SVD was categorized using a threshold of =40% WMLs with central veins as indicative of MS. Interrater and intrarater reproducibility was calculated. Results The mean proportion of WMLs with central veins was 68.4% in PPMS, 74.3% in RRMS, and 4.7% in SVD. The difference in proportions between PPMS and SVD groups was significant (p < 0.0005; effect size: 3.8) but not significant between MS subtypes (p = 0.3; effect size: 0.29). Distribution of WMLs was similar across both MS groups, but despite SVD patients having more DWM lesions than PPMS patients, proportions of WMLs with central veins remained low (2.75% in SVD; 62.5% in PPMS). Interrater and intrarater reproducibility comparing proportions of WMLs with central veins across all patients was 0.86 and 0.90, respectively. Level of agreement between the proportion of WML central veins and established diagnosis was 0.84 and 0.82 for each rater. Conclusions WML central veins could be used to differentiate PPMS from SVD but not between MS subtypes

Conditional mouse models demonstrate oncogene-dependent differences in tumor maintenance and recurrence

Diversity in the pathophysiology of breast cancer frustrates therapeutic progress. We need to understand how mechanisms activated by specific combinations of oncogenes, tumor suppressors, and hormonal signaling pathways govern response to therapy and prognosis. A recent series of investigations conducted by Chodosh and colleagues offers new insights into the similarities and differences between specific oncogenic pathways. Expression of three oncogenes relevant to pathways activated in human breast cancers (c-myc, activated neu and Wnt1) were targeted to murine mammary epithelial cells using the same transgenic tetracycline-responsive conditional gene expression system. While the individual transgenic lines demonstrate similarly high rates of tumor penetrance, rates of oncogene-independent tumor maintenance and recurrence following initial regression are significantly different, and are modifiable by mutations in specific cooperating oncogenes or loss of tumor suppressor gene expression. The experiments make three notable contributions. First, they illustrate that rates of tumor regression and recurrence following initial regression are dependent upon the pathways activated by the initiating oncogene. The experiments also demonstrate that altered expression or mutation of specific cooperating oncogenes or tumor suppressor genes results in different rates of tumor regression and recurrence. Finally, they exemplify the power of conditional mouse models for elucidating how specific molecular mechanisms give rise to the complexity of human cancer

Changes in the ornithine cycle following ionising radiation cause a cytotoxic conditioning of the culture medium of H35 hepatoma cells

Cultured H35 hepatoma cells release a cytotoxic factor in response to irradiation with X-rays. When the conditioned medium from irradiated cells is given to nonirradiated cells, growth is inhibited and followed by cell death, possibly apoptosis, Analysis of the conditioned medium reveals a dramatic change in the ornithine (urea) cycle components after the irradiation. A strong decrease in medium arginine is accompanied with parallel increases in ornithine, citrulline and ammonia. The high level of ammonia appears to be largely responsible for the observed cytotoxicity. The development of hyperammonia by irradiated cells and the related toxicity depend on the radiation dose and the number of cells seeded thereafter for the medium conditioning. Development of cytotoxicity by irradiated cells is completely prevented with the arginase inhibitor L-norvaline, in arginine-deficient medium or when citrulline replaces arginine. These preventive measures result in subtoxic ammonia levels

Plasma Insulin-like Growth Factors, Insulin-like Binding Protein-3, and Outcome in Metastatic Colorectal Cancer: Results from Intergroup Trial N9741

Insulin-like growth factor (IGF)-I and IGF-II stimulate neoplastic cell growth and inhibit apoptosis, whereas IGF-binding protein-3 (IGFBP-3) inhibits the bioavailability of IGF-I and has independent proapoptotic activity. We examined the influence of baseline plasma levels of IGF-I, IGF-II, IGFBP-3, and C-peptide on outcome among patients receiving first-line chemotherapy for metastatic colorectal cancer