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Summary MDCK cells (epithelioid of renal origin) form monolayers which are structurally and functionally similar to transporting epithelia. One of these similarities is the ability to form occluding junctions and act as permeability barriers. This article studies the junctions of MDCK monolayers formed on a permeable and transparent support (a disk of nylon cloth coated with collagen) by combining two different approaches: (i)Scanning of the electric field: the disk is mounted as a flat sheet between two Lucite chambers and pulses of 20–50 µA cm-2 are passed across. The apical surface of the monolayer is then scanned with a microelectrode to detect those points where the current is flowing. This shows that the occluding junctions of this preparation are not homogeneous, but contain long segments of high resistance, intercalated with sites of high conductance. (ii)Freeze fracture electron microscopy: the junctions are composed of regions of eight to ten strands intercalated with others where the strands are reduced to one or two ridges. The sites of high conductance may correspond to those segments where the number of junctional strands is reduced to 1 or 2. It is concluded that the occluding junctions of MDCK monolayers are functionally and morphologically heterogeneous, with “tight” regions intermixed with “leaky” ones.

Between November 1978 and July 1991, ten children between one and eight years of age with Group III pelvic rhabdomyosarcoma (IRS classification) and considered inoperable at diagnosis were treated primarily with intensive poly-chemotherapy. Complementary radiotherapy and conservative surgery were added as needed. Eight of the ten survive free of disease with functioning bladders for periods ranging from 5.7–18.4 years. Med. Pediatr. Oncol. 29:573–575, 1997. © 1997 Wiley-Liss, Inc.

The study consisted of two stages Phase 1: Cell assay adding metformin (40mM) assessing the viability and cell cycle in the cell line molt 4 Phase 2: Pilot study adding Metformin (850mg three time day) during the pre-treatment with steroids and the induction remission phase versus a control group (2:1 randomization)Chi-square analysis was used to corroborate the hypothesis. The odds ratio was calculated for both, the absence of Good steroid response and refractory leukemia. Cox regression analysis and Kaplan-Meier curves were used for the survival analysisCelular assay. Metformin inhibited cell viability at 120hours reducing the percentage of cells in phase S. Clinical assay. 151 patients were studied, 44 (29.1%) on Metformin arm, of these 59.1% ( n=26) archived a GSR compared with the control group (26.2%, n=28). A greater number of complete remission were presented in Metformin arm (81.8% versus 57.9%) shown to be a protective factor for GSR and complete remissions (odds ratio ; 0.2454 y 0.3062 respectively). In the Cox regression analysis, Metformin significantly impact in the global survival (p=0,012,95% IC) versus the other variables studied.Metformin is useful both in vivo and in vitro treatment of adult acute lymphoblastic leukemia.No relevant conflicts of interest to declare.

No relevant conflicts of interest to declare.

Targeted therapy commenced against Chronic Myeloid Leukemia (CML) with the development of small-molecule tyrosine kinase inhibitors (TKIs), since its approval in 2001 as first-line therapy, imatinib has been effective in achieving high response rates and improving the prognosis. However, the excellent results of large clinical trials are not entirely reproducible in the “real world”, we want to share our experience of a decade of use as front-line treatment.

Antitumor effects of metformin are widely known. Unfortunately their use in the treatment of acute lymphoblastic leukemia is limited.

Hemocytes of 2- to 3-d-old female Anopheles albimanus Wiedemann are described by morphology, cytochemistry, and functional criteria. Supplemented Grace's insect medium in a modified Foley's perfusion method was used to obtain hemolymph from An. albimanus. Morphological analysis indicated 3 types of hemocytes were present, prohemocytes, plasmatocytes, and granular cells. Prohemocytes were small round cells with a high nuclear/cytoplasmic ratio. Plasmatocytes were the most abundant cell type in the hemolymph, and appeared as small to large and spindle-shaped cells with round or elongate nucleus, variable number of vacuoles, small granules, and pseudopodia. Granular cells were small to large and round with a large number of cytoplasmic granules, vacuoles, and numerous filopodia. Ultrastructurally, prohemocytes were undifferentiated with abundant free ribosomes and with few small electron-dense granules. Plasmatocytes were rich in mitochondria, rough endoplasmic reticulum, free ribosomes, small electron-dense granules, numerous peripheral vacuoles and with an important organelle polarization. Granular cells contained numerous large electron-dense granular inclusions and vacuoles. Cytochemical studies showed that plasmatocytes and granular cells have cationic bactericidal proteins. Only granular cells showed phenoloxidase and probably lysosomal activities. In vitro functional studies demostrated that both plasmatocytes and granular cells were able to attach to glass slides, and only plasmatocyte had phagocytic activity and motility. These results characterize the hemocytes of An. albimanus and suggest that plasmatocytes and granular cells may have a role in defense responses to foreign organisms.