A microdevice for parallelized pulmonary permeability studies

We describe a compartmentalized microdevice specifically designed to perform permeability studies across a model of lung barrier. Epithelial cell barriers were reproduced by culturing Calu-3 cells at the air-liquid interface (AIC) in 1 mm² microwells made from a perforated glass slide with an embedded porous membrane. We created a single basolateral reservoir for all microwells which eliminated the need to renew the growth medium during the culture growth phase. To perform drug permeability studies on confluent cell layers, the cell culture slide was aligned and joined to a collection platform consisting in 35 μL collection reservoirs connected at the top and bottom with microchannels. The integrity and functionality of the cell barriers were demonstrated by measurement of trans-epithelial electrical resistance (TEER), confocal imaging and permeability assays of ¹⁴C-sucrose. Micro-cell barriers were able to form confluent layers in 1 week, demonstrating a similar bioelectrical evolution as the Transwell systems used as controls. Tight junctions were observed throughout the cell-cell interfaces, and the low permeability coefficients of ¹⁴C-sucrose confirmed their functional presence, creating a primary barrier to the diffusion of solutes. This microdevice could facilitate the monitoring of biomolecule transport and the screening of formulations promoting their passage across the pulmonary barrier, in order to select candidates for pulmonary administration to patients.     

Mitoxantrone-containing regimen for treatment of childhood acute leukemia AML and analysis of prognostic factors: Results of the EORTC Children Leukemia Cooperative Study 58872

The objective of this study was to evaluate the feasibility, the toxicity and the efficiency of a BFM-like treatment protocol for acute nonlymphoblastic leukemia (ANLL) of children in which mitoxantrone was substituted for conventional anthracycline. The chemotherapy called for induction (mitoxantrone, cytosine arabinoside, etoposide), consolidation (mitoxantrone, cytosine arabinoside, 6 thioguanine), followed by two intensification courses with cytosine arabinoside plus, respectively, mitoxantrone during the first and etoposide during the second courses. Maintenance therapy consisted of daily 6 thioguanine, four-weekly courses of cytosine arabinoside (s.c. daily during 4 days) and eight-weekly courses of mitoxantrone. The latter drug was pursued up to a total cumulative dose of 150 mg/sqm. Maintenance therapy was stopped at 2 years of diagnosis. Out of 108 patients, 84 (77%) achieved a complete remission, 10 died during induction of hemorrhage, sepsis or pulmonary infiltration by leukemic cells. A total of 32 relapses occurred. The median follow-up was 3.5 years. Actuarial event-free survival, disease-free survival and overall survival at 3 years as 41%, 52%, 56%;, respectively. These results compare favorably with most reported data, and cytogenetic findings appear to be the most important prognostic factor. © 1996 Wiley-Liss, Inc.     

Validation of a new standardized cystatin C turbidimetric assay: Evaluation of the three novel CKD-EPI equations in hypertensive patients

Objectives

Analytical and clinical performances of the new standardized cystatin C particle-enhanced turbidimetric immunoassay (PETIA) using DiaSys reagents on Olympus AU2700® analyzer were evaluated.

Design and methods

We have studied imprecision, linearity, limit of detection and limit of quantification of this new immunoassay. Method comparison was assessed in relation to results generated by the standardized Siemens-particle-enhanced nephelometric immunoassay (PENIA). In order to evaluate the clinical relevance of this assay, estimated glomerular filtration rate (GFR) was calculated using MDRD, CKD-EPI creatinine, CKD-EPI cystatin C 2012 and CKD-EPI creatinine–cystatin C 2012 equations and compared to GFR measured using urinary clearance of ^99mTc-DTPA in 100 hypertensive patients.

Results

Cystatin C measurements using DiaSys reagents have reliable analytical performances and are comparable to the standardized Siemens-PENIA method (bias of 0.01 mg/L). The mean measured GFR was 90.0 ± 29.7 mL/min/1.73 m². Bias and accuracy of the three CKD-EPI equations were better than the MDRD. Both CKD-EPI creatinine-based and cystatin C-based formulae had similar bias, precision and accuracy. The combined creatinine–cystatin C equation was significantly more accurate and precise than the CKD-EPI creatinine equation in patients with GFR above 60 mL/min/1.73 m².

Conclusions

The use of cystatin C in a combined equation with creatinine could improve the accuracy of eGFR in the reference interval.     

Proadrenomedullin,a useful tool for risk stratification in high Pneumonia Severity Index score community acquired pneumonia

The aim of the present study was, first, to evaluate the prognostic value of mid-regional proadrenomedullin (proADM) in emergency department (ED) patients with a diagnosis of community acquired pneumonia (CAP) and, second, to analyze the added value of proADM as a risk stratification tool in comparison with other biomarkers and clinical severity scores.     

Trends in incidence of small bowel cancer according to histology: a population-based study

Journal of Gastroenterology - Small bowel cancer is not a single entity. Population-based studies taking into account histological diversity are scarce. The aim of this study was to report on their...     

Biphenylsulfonacetic acid inhibitors of the human papillomavirus type 6 E1 helicase inhibit ATP hydrolysis by an allosteric mechanism involving tyrosine 486

Human papillomaviruses (HPVs) are the causative agents of benign and malignant lesions of the epithelium. Despite their high prevalence, there is currently no antiviral drug for the treatment of HPV-induced lesions. The ATPase and helicase activities of the highly conserved E1 protein of HPV are essential for viral DNA replication and pathogenesis and hence are considered valid antiviral targets. We recently described novel biphenylsulfonacetic acid inhibitors of the ATPase activity of E1 from HPV type 6 (HPV6). Based on kinetics and mutagenesis studies, we now report that these compounds act by an allosteric mechanism. They are hyperbolic competitive inhibitors of the ATPase activity of HPV6 E1 and also inhibit its helicase activity. Compounds in this series can also inhibit the ATPase activity of the closely related enzyme from HPV11; however, the most potent inhibitors of HPV6 E1 are significantly less active against the type 11 protein. We identified a single critical residue in HPV6 E1, Tyr-486, substituted by a cysteine in HPV11, which is primarily responsible for this difference in inhibitor potency. Interestingly, HPV18 E1, which also has a tyrosine at this position, could be inhibited by biphenylsulfonacetic acid derivatives, thereby raising the possibility that this class of inhibitors could be optimized as antiviral agents against multiple HPV types. These studies implicate Tyr-486 as a key residue for inhibitor binding and define an allosteric pocket on HPV E1 that can be exploited for future drug discovery efforts.