The infectivity of sarcoid clinical material and its bacterial content inoculated in CBA mice.

Background: Sarcoidosis is a multisystemic disorder that is currently viewed as the consequence of chronic immunological response associating genetic susceptibility and specific environmental or transmissible agents. Relevant evidence, although conflicting, justifies a concern about the involvement of specific pathogens to disease causation. In this study we assessed the infectivity of sarcoid clinical material, and of the pathogens found in it, to normal CBA mice used as a model of an immuno-competent host.

Oncogene-induced senescence is part of the tumorigenesis barrier imposed by DNA damage checkpoints.

Recent studies have indicated the existence of tumorigenesis barriers that slow or inhibit the progression of preneoplastic lesions to neoplasia. One such barrier involves DNA replication stress, which leads to activation of the DNA damage checkpoint and thereby to apoptosis or cell cycle arrest, whereas a second barrier is mediated by oncogene-induced senescence. The relationship between these two barriers, if any, has not been elucidated.

Population pharmacokinetics of high-dose methotrexate in children with acute lymphoblastic leukaemia.

Objective: To develop and a priori validate a methotrexate population pharmacokinetic model in children with acute lymphoblastic leukaemia (ALL), receiving high-dose methotrexate followed by folinic acid rescue, identifying the covariates that could explain part of the pharmacokinetic variability of methotrexate.

Methods: The study was carried out in 49 children (aged 6 months to 17 years) who received high-dose methotrexate (3 g/m(2) per course) in long-term treatment. In an index group (37 individuals; 1236 methotrexate plasma concentrations), a population pharmacokinetic model was developed using a nonlinear mixed-effects model.

Chk1-dependent regulation of Cdc25B functions to coordinate mitotic events.

The coordination of mitotic spindle formation and chromatin condensation is an essential prerequisite for successful mitosis. Both events are thought to be initiated by cyclin B/Cdk1, whose initial activation occurs in late prophase at the centrosomes. Recently, we have shown that Chk1 localizes to interphase centrosomes and thereby negatively regulates entry into mitosis by preventing premature activation of cyclin B/Cdk1.

Comparative evaluation of positive tests to Mycobacterium avium subsp. paratuberculosis in clinically healthy sheep and goats in south-west Greece using molecular techniques, serology, and culture.

Mycobacterium avium subsp. paratuberculosis (MAP) is the cause of paratuberculosis, which affects mainly ruminants although there is a growing concern about its possible implication in Crohn's disease in humans especially in connection with environmental spread and risks to the food chain. Retail cheese may represent a significant source of human exposure to MAP and the aim of this study was to assess MAP status in clinically healthy sheep and goats in Greece, comparing techniques routinely used in the positive diagnosis of the disease.

Retinoblastoma pathway defects show differential ability to activate the constitutive DNA damage response in human tumorigenesis.

Loss of G(1)-S control and aberrations of the p16(Ink4a)-cyclin D1/cyclin-dependent kinase (CDK) 4(6)-pRb-E2F-cyclin E/CDK2 pathway are common in human cancer. Previous studies showed that oncogene-induced aberrant proliferation, such as on cyclin E overexpression, causes DNA damage and checkpoint activation. Here, we show that, in a series of human colorectal adenomas, those with deregulation of cyclin D1 and/or p16(Ink4a) showed little evidence of constitutive DNA damage response (DDR), contrary to cyclin E-overexpressing higher-grade cases.

Adaptation to the ionizing radiation-induced G2 checkpoint occurs in human cells and depends on checkpoint kinase 1 and Polo-like kinase 1 kinases.

Checkpoint adaptation was originally defined in yeast as the ability to divide despite the presence of damaged DNA. An important unanswered question is whether checkpoint adaptation also occurs in human cells. Here, we show that following the ionizing radiation-induced G(2) checkpoint, human osteosarcoma cells entered mitosis with gamma-H2AX foci, a marker for unrepaired DNA double-strand breaks.

Destruction of Claspin by SCFbetaTrCP restrains Chk1 activation and facilitates recovery from genotoxic stress.

We show that Claspin, an adaptor protein required for Chk1 activation, becomes degraded at the onset of mitosis. Claspin degradation was triggered by its interaction with, and ubiquitylation by, the SCFbetaTrCP ubiquitin ligase. This interaction was phosphorylation dependent and required the activity of the Plk1 kinase and the integrity of a betaTrCP recognition motif (phosphodegron) in the N terminus of Claspin.

Claspin operates downstream of TopBP1 to direct ATR signaling towards Chk1 activation.

TopBP1 and Claspin are adaptor proteins that facilitate phosphorylation of Chk1 by the ATR kinase in response to genotoxic stress. Despite their established requirement for Chk1 activation, the exact way in which TopBP1 and Claspin control Chk1 phosphorylation remains unclear. We show that TopBP1 tightly colocalizes with ATR in distinct nuclear subcompartments generated by DNA damage.

Chromatin relaxation in response to DNA double-strand breaks is modulated by a novel ATM- and KAP-1 dependent pathway.

The cellular DNA-damage response is a signaling network that is vigorously activated by cytotoxic DNA lesions, such as double-strand breaks (DSBs). The DSB response is mobilized by the nuclear protein kinase ATM, which modulates this process by phosphorylating key players in these pathways. A long-standing question in this field is whether DSB formation affects chromatin condensation.

Structure meets function--centrosomes, genome maintenance and the DNA damage response.

Centrosomes are cytoplasmic organelles playing a fundamental role in organizing both the interphase cytoskeleton and the bipolar mitotic spindle. In addition, the centrosome has recently come into focus as part of the network that integrates cell cycle arrest and repair signals in response to genotoxic stress--the DNA damage response. One important mediator of this response, the checkpoint kinase Chk1, has been shown to negatively regulate the G(2)/M transition via its centrosomal localization.

IL-2 immunotoxin therapy modulates tumor-associated regulatory T cells and leads to lasting immune-mediated rejection of breast cancers in neu-transgenic mice.

Studies in cancer patients have suggested that breast tumors recruit regulatory T cells (Tregs) into the tumor microenvironment. The extent to which local Tregs suppress antitumor immunity in breast cancer is unknown. We questioned whether inhibiting systemic Tregs with an IL-2 immunotoxin in a model of neu-mediated breast cancer, the neu-transgenic mouse, could impact disease progression and survival.

Fine-needle aspiration biopsy in the diagnostic of the tumors and non-neoplastic lesions of salivary glands.

Objectives: Fine-needle aspiration biopsy (FNAB) has not been part of the basic algorithm of preoperative evaluation of tumors of the major salivary glands in the Czech Republic. Most opponents of salivary gland FNAB consider it unnecessary. This paper documents the utility of the punction aspiration biopsy in the diagnosis of these lesions.

Proprioception in the extraocular muscles of mammals and man.

This article summarizes the authors' previous studies on proprioceptors in extraocular muscles (EOMs) of mammals and man. They report on muscle spindles in the EOMs of man, Golgi tendon organs in the EOMs of even-toed ungulates, and palisade endings in the EOMs of the cat. Muscle spindles: Muscle spindles are present in the EOMs of some mammals and in the EOMs of man.

HIC1 attenuates Wnt signaling by recruitment of TCF-4 and beta-catenin to the nuclear bodies.

The hypermethylated in cancer 1 (HIC1) gene is epigenetically inactivated in cancer, and in addition, the haploinsufficiency of HIC1 is linked to the development of human Miller-Dieker syndrome. HIC1 encodes a zinc-finger transcription factor that acts as a transcriptional repressor. Additionally, the HIC1 protein oligomerizes via the N-terminal BTB/POZ domain and forms discrete nuclear structures known as HIC1 bodies.

Spatial organization of the mammalian genome surveillance machinery in response to DNA strand breaks.

We show that DNA double-strand breaks (DSBs) induce complex subcompartmentalization of genome surveillance regulators. Chromatin marked by gamma-H2AX is occupied by ataxia telangiectasia-mutated (ATM) kinase, Mdc1, and 53BP1. In contrast, repair factors (Rad51, Rad52, BRCA2, and FANCD2), ATM and Rad-3-related (ATR) cascade (ATR, ATR interacting protein, and replication protein A), and the DNA clamp (Rad17 and -9) accumulate in subchromatin microcompartments delineated by single-stranded DNA (ssDNA).

The role of unbound drug in pharmacokinetics/pharmacodynamics and in therapy.

The evolution of research on drug protein binding is discussed with the unbound concentration (Cu) and the unbound fraction (fu) as protagonists. Particular attention is paid to the mechanisms via which alterations in binding affect the pharmacokinetics (PK) and the effect, or independently the pharmacodynamics (PD). Apart from albumin, the important alpha-acid glycoprotein (AGP), as well as specific drug classes and applications in the clinic and development (routine monitoring, cancer and HIV therapy, allometry) are addressed.

Using statistical process control methods to improve herd performance.

Statistical process control (SPC) is a set of analytic methods that uses the theory of variation as a means of explaining with statistical certainty when process performance is improving, staying the same, or getting worse. SPC techniques have been used successfully for 80 years in manufacturing as a quality management tool. It is apparent that these techniques can be applied equally well to livestock production systems.

Cellular responses to DNA damage: current state of the field and review of the 52nd Benzon Symposium.

The response of cells to DNA damage is critical for maintaining genomic integrity and for preventing cancer development. Current advances in our understanding of the response of cells to DNA double-strand breaks and to stalled DNA replication forks and the relationship of these responses to human disease were discussed at the 52nd Benzon Symposium in Denmark, Copenhagen. Here we review the novel findings that were presented at this Symposium and the current state of the field.

'Blind' antibiotic treatment targeting Chlamydia is not effective in patients with MALT lymphoma of the ocular adnexa.

Background: Recent results have implicated Chlamydia, especially Chlamydia psittaci, in the development of ocular adnexal lymphoma in the large majority of patients. We present our experience with ex-juvantibus antibiotic treatment in patients diagnosed with MALT lymphoma of the ocular adnexa.

Patients And Methods: A retrospective analysis identified a total of 11 patients (six female, five male) with MALT-lymphoma of the ocular adnexa who were given doxycyclin 200 mg p.

Time-dependent pharmacokinetics of cyclosporine (Neoral) in de novo renal transplant patients.

Purpose: A model for the large scale temporal trend in the oral bioavailability of microemulsion cyclosporine (Neoral) (CsA) is established, with dependence on post-(renal) transplantation day (PTD).

Methods: Twenty de novo adult renal transplant recipients were monitored for CsA administered orally q12 h. A model development group (11 patients, 315 blood concentration samples) was screened at 2 h (C(2); n = 92), 3 h (C(3); n = 56) and at predose troughs (C(min); n = 167) over periods of up to 75 days.

Detection of Mycobacterium avium subsp. paratuberculosis in retail cheeses from Greece and the Czech Republic.

We investigated the presence of Mycobacterium avium subsp. paratuberculosis in retail cheeses from Greece and the Czech Republic. We found that 31.

ATM- and cell cycle-dependent regulation of ATR in response to DNA double-strand breaks.

It is generally thought that the DNA-damage checkpoint kinases, ataxia-telangiectasia mutated (ATM) and ATM- and Rad3-related (ATR), work independently of one another. Here, we show that ATM and the nuclease activity of meiotic recombination 11 (Mre11) are required for the processing of DNA double-strand breaks (DSBs) to generate the replication protein A (RPA)-coated ssDNA that is needed for ATR recruitment and the subsequent phosphorylation and activation of Chk1. Moreover, we show that efficient ATM-dependent ATR activation in response to DSBs is restricted to the S and G2 cell cycle phases and requires CDK kinase activity.