Instrument Calibration of the Interface Region Imaging Spectrograph (IRIS) Mission.

The Interface Region Imaging Spectrograph (IRIS) is a NASA small explorer mission that provides high-resolution spectra and images of the Sun in the 133 - 141 nm and 278 - 283 nm wavelength bands. The IRIS data are archived in calibrated form and made available to the public within seven days of observing. The calibrations applied to the data include dark correction, scattered light and background correction, flat fielding, geometric distortion correction, and wavelength calibration. In addition, the IRIS team has calibrated the IRIS absolute throughput as a function of wavelength and has been tracking throughput changes over the course of the mission. As a resource for the IRIS data user, this article describes the details of these calibrations as they have evolved over the first few years of the mission. References to online documentation provide access to additional information and future updates.

A microRNA gene expression signature predicts response to erlotinib in epithelial cancer cell lines and targets EMT.

BACKGROUND: Treatment with epidermal growth factor receptor (EGFR) inhibitors can result in clinical response in non-small-cell lung cancer (NSCLC) and pancreatic ductal adenocarcinoma (PDAC) for some unselected patients. EGFR and KRAS mutation status, amplification of EGFR, or gene expression predictors of response can forecast sensitivity to EGFR inhibition. METHODS: Using an NSCLC cell line model system, we identified and characterised microRNA (miRNA) gene expression that predicts response to EGFR inhibition. RESULTS: Expression of 13 miRNA genes predicts response to EGFR inhibition in cancer cell lines and tumours, and discriminates primary from metastatic tumours. Signature genes target proteins that are enriched for epithelial-to-mesenchymal transition (EMT) genes. Epithelial-to-mesenchymal transition predicts EGFR inhibitor resistance and metastatic behaviour. The EMT transcription factor, ZEB1, shows altered expression in erlotinib-sensitive NSCLC and PDAC, where many signature miRNA genes are upregulated. Ectopic expression of mir-200c alters expression of EMT proteins, sensitivity to erlotinib, and migration in lung cells. Treatment with TGFß1 changes expression of signature miRNA and EMT proteins and modulates migration in lung cells. CONCLUSION: From these data, we hypothesise that the tumour microenvironment elicits TGFß1 and stimulates a miRNA gene expression program that induces resistance to anti-EGFR therapy and drives lung tumour cells to EMT, invasion, and metastasis.

Spin-labeled analogues of ATP, ADP and AMP: substitutes for normal nucleotides in biochemical systems.

The different roles and effectiveness of adenosine monophosphate, diphosphate and triphosphate labeled at the 6 position of the purine ring with 2,2,6,6-tetramethylpiperidine-1-oxyl in reactions catalyzed by Escherichia coli glutamine synthetase (GS) have been investigated. Our results show that the spin-labeled ATP (Tempo-ATP) serves as a substrate in the glutamine synthesis reaction and in the adenylation of E. coli glutamine synthetase catalyzed by ATP: glutamine adenylyl transferase (ATase) with essentially the same effectiveness as normal ATP. In another reaction (gamma-glutamyltransferase), Tempo ADP serves as an effector with a Km of 9.4 . 10(-8) M compared to 1.2 . 10(-8) M for the normal ADP, while covalently bonded Tempo-AMP serves as a modifier on the catalytic properties of E. coli glutamine synthetase just as the covalently bonded normal AMP does. The dissociation constants between the labeled nucleotides, Mn2+, Mg2+ and Ca2+ are in the same order of magnitude as the binding constants for those cations and the corresponding normal nucleotides. Our findings indicate that the spin-labeled nucleotides are good substitutes for the normal nucleotides in the biochemical systems studied.

An antisuppressor mutant of Saccharomyces cerevisiae deficient in isopentenylated tRNA has reduced delta 2-isopentenylpyrophosphate: tRNA-delta 2-isopentenyl transferase activity.

We have previously reported the isolation and initial characterization of a mutation in Saccharomyces cerevisiae, designated mod5-1, that reduces the capacity of altered tyrosine tRNAs to suppress ochre nonsense mutations. The mutation results in the virtual elimination of the modified tRNA nucleoside, N6-delta 2-(isopentenyl) adenosine, normally found adjacent to the anticodons of certain tRNA species. We demonstrate here that MOD5 codes for delta 2-isopentenylpyrophosphate: tRNA-delta 2-isopentenyl transferase, or a protein that regulates its synthesis.

Surface-MALDI mass spectrometry in biomaterials research.

Matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS) has been used for over a decade for the determination of purity and accurate molecular masses of macromolecular analytes, such as proteins, in solution. In the last few years the technique has been adapted to become a new surface analysis method with unique capabilities that complement established biomaterial surface analysis methods such as XPS and ToF-SSIMS. These new MALDI variant methods, which we shall collectively summarize as Surface-MALDI-MS, are capable of desorbing adsorbed macromolecules from biomaterial surfaces and detecting their molecular ions with high mass resolution and at levels much below monolayer coverage. Thus, Surface-MALDI-MS offers unique means of addressing biomaterial surface analysis needs, such as identification of the proteins and lipids that adsorb from multicomponent biological solutions in vitro and in vivo, the study of interactions between biomaterial surfaces and biomolecules, and identification of surface-enriched additives and contaminants. Surface-MALDI-MS is rapid, experimentally convenient, overcomes limitations in mass resolution and sensitivity of established biochemical techniques such as SDS-PAGE, and can in some circumstances be used for the quantitative analysis of adsorbed protein amounts. At this early stage of development, however, limitations exist: in some cases proteins are not detectable, which appears to be related to tight surface binding. This review summarizes ways in which Surface-MALDI-MS methods have been applied to the study of a range of issues in biomaterials surfaces research.

Enhancing hepatocyte adhesion by pulsed plasma deposition and polyethylene glycol coupling.

Decreased hepatocyte adhesion to polymeric constructs limits the function of tissue engineered hepatic assist devices. We grafted adhesion peptides (RGD and YIGSR) to polycaprolactone (PCL) and poly-L-lactic acid (PLLA) in order to mimic the in vivo extracellular matrix and thus enhance hepatocyte adhesion. Peptide grafting was done by a novel technique in which polyethylene glycol (PEG)-adhesion peptide was linked to allyl-amine coated on the surface of PCL and PLLA by pulsed plasma deposition (PPD). Peptide grafting density, quantified by radio-iodinated tyrosine in YIGSR, was 158 fmol/cm(2) on PLLA and 425 fmol/cm(2) on PCL surfaces. The adhesion of hepatocytes was determined by plating 250,000 hepatocytes/well (test substrates were coated on 12 well plates) and quantifying the percentage of adhered cells after 6 h by MTT assay. Adhesion on PCL surfaces was significantly enhanced (p < 0.05) by both YIGSR (percentage of adhered cells = 53 +/- 7%) and RGD (53 +/- 12%) when compared to control surfaces (31 +/- 8%). Hepatocyte adhesion on PLLA was significantly (p < 0.05) enhanced on PLLA-PEG-RGD surfaces (76 +/- 14%) compared to control surfaces (42 +/- 19%) and more (68 +/- 25%) but not statistically significant (p = 0.15) on PLLA-PEG-YIGSR surfaces compared to control surfaces. These results indicate that hepatocyte adhesion to PCL and PLLA based polymeric surfaces can be enhanced by a novel adhesion peptide grafting technique using pulsed plasma deposition and PEG cross-linking.

Comparison of three transport systems for recovery of aerobes and anaerobes from wounds.

A clinical evaluation of three commercially available transport systems (Anaerobic Specimen Collector, Becton-Dickenson; Anaswab, Scott Laboratories; and Trans-Cul, Wampole) was done, using as subjects 75 patients suspected of having infections. Holding times were purposely varied and ranged from 30 min to 48 hours. Totals of 22 aerobic species and 15 anaerobic species were isolated. There was essentially no difference among the three systems in the recoveries of aerobic or anaerobic organisms. Discrepancies appeared to be related to the order of collection and amount of clinical material available for culture. Time delay from collection to plating did not affect the recovery of aerobes or anaerobes. The three systems performed equally in the recovery of clinically significant pathogens from purulent clinical material.

Patterns of obstetric procedures use in maternity care.

The use of seven obstetric procedures was studied in two institutions that use different approaches to maternity care. The study population included 796 women delivering at Booth Maternity Center and 804 women with similar sociodemographic characteristics delivering at Thomas Jefferson University Hospital during 1977 and 1978. Several differences were found between the two institutions. The majority of selected procedures were used more often at Thomas Jefferson University Hospital than at Booth Maternity Center. The greatest differences were found for women at low intrapartum risk, while differences were smallest for women at high prenatal and intrapartum risk. The two institutions differed in their use of procedures for women at various levels of prenatal and intrapartum risk. The findings suggested that most of the differences did not reflect different levels of risk in the populations served, but were due to other unidentified factors.

Pulsed plasma deposition of allylamine on polysiloxane: a stable surface for neuronal cell adhesion.

Allylamine was pulse-plasma polymerized onto a hydrophobic polysiloxane substrate to create cell adhesion surfaces for cell culture that would not require pretreatment with polylysine, could be sterilized via autoclaving, and could be re-used for several culture cycles. We investigated two different plasma deposition protocols at 200 W RF power: (1) a duty cycle of 3 ms on and 5 ms off; and (2) a cycle of 3 ms on and 45 ms off. Control surfaces were unmodified polysiloxane, activated polysiloxane via flaming, and flamed polysiloxane further modified with poly-D-lysine (PDL). The different surfaces were characterized with XPS analysis, water contact angle, and cell adhesion and growth using dissociated murine embryonic spinal tissue. We found that both the amine content of the 3/45 duty cycle surface and the wettability was higher than that of the 3/5 surface. Also, spinal cord cells were better dispersed 24 h after seeding on the 3/45 surface, suggesting a difference in early adhesion dynamics. However, the networks on the two types of modified surfaces revealed no obvious morphological differences after 2 weeks in vitro. The stability of allylamine-decorated surfaces after autoclaving was high with only minor changes in wettability and nitrogen content. Cell growth on such surfaces after autoclaving was comparable to that found on flamed polysiloxane, freshly modified with PDL. Allylamine surfaces were still usable as cell growth substrates after three autoclaving cycles, 4 weeks under warm culture medium, and simple cleaning procedures, indicating the achievement of a long-lasting modification that did not require the repeated use of PDL before each seeding.

Pulsed plasma discharge polymer coatings.

The authors studied a pulsed radiofrequency glow discharge polymer film deposition method (pRFGD) on polyethylene terephthalate (PET), silicon (Si), and potassium chloride (KCl) surfaces, with the aim of better controlling film uniformity and homogeneity. A pulse generator was used to control a conventional 13.56 MHz RFGD circuit to provide plasma on and off times throughout a wide range of duty cycles. Starting monomers included fluorocarbon monomers (C8F16O and C3F6O) and more conventional unsaturated monomers [acrylonitrile (C3H3N) and vinyl trimethyl silane (C5H12Si)]. With each of these monomers progressive, large scale changes in the molecular structure of the plasma deposited films were noted with systematic variations in the RF duty cycle. Film characterizations were performed using electron spectroscopy for chemical analysis (ESCA) and fourier transform infrared (FTIR) analysis. In the case of fluorocarbon (FC) films, systematically decreasing plasma on time at a constant off time resulted in enhanced CF2 and CF3 content compared with that seen with the less highly fluorinated groups. There was virtually no oxygen atom incorporation in the FC films obtained from the oxygen containing monomers. Overall, a dramatic decrease in cross-linking of the FC polymer films was observed with decreasing RF duty cycles. A highly ordered Teflon-like structure was obtained for the lowest duty cycles. In the silane experiments, a systematic variation in the ratio of Si-H/Si-CH3 groups was observed, with this ratio increasing as the RF duty cycle decreased. Experiments with C3H3N revealed an increasing surface density of -CN groups with decreasing RF duty cycle.(ABSTRACT TRUNCATED AT 250 WORDS)

Fine needle aspiration cytology of primary epidermoid cyst of the brain.

The cytologic features of a primary epidermoid cyst of the brain diagnosed by intraoperative fine needle aspiration cytology are reported. The cytomorphologic findings included numerous anucleated squames, polarizable cholesterol crystals and a few squamous cells with keratohyaline granules. This case demonstrated the efficacy of using both the Diff-Quik and Papanicolaou stains in evaluation of cystic lesions of the brain. A discussion of the expected aspiration cytologic findings of other cystic cerebral lesions is also presented.

Inappropriate antidiuretic hormone following adenine arabinoside administration.

A patient with disseminated herpes zoster developed a syndrome of inappropriate antidiuretic hormone and profound hyponatremia secondary to the administration of adenine arabinoside.

Infection of the respiratory tract with Mammomanogamus (Syngamus) laryngeus: a new case in Largo, Florida, and a summary of previously reported cases.

We present an unusual cause for chronic cough. Infection in a man by the nematode Mammomanogamus laryngeus is described along with a review of other reported human cases. High index of suspicion is urged, especially in world travelers.

Fibrinogen adsorption and host tissue responses to plasma functionalized surfaces.

The physical and chemical characteristics of material surfaces are thought to play important roles in biomaterial-mediated tissue responses. To understand the importance of discrete biomaterial chemical characteristics in modifying host tissue responses, we constructed surfaces bearing different functional groups using radio frequency glow discharge plasma polymerization. Surfaces evaluated included those having high concentrations of -OH, -NH2, -CF3, and siloxyl groups. These surfaces and polyethylene terephthalate controls were used to assess the importance of particular physicochemical characteristics in surface:protein:cell interactions both in vitro and in vivo. The results obtained show that surface functionalities do significantly affect both the adsorption and "denaturation" of adsorbed fibrinogen (which is an important mediator of inflammatory responses to biomaterial implants). In addition, these surfaces provoke different degrees of acute inflammatory responses. Interestingly, the amounts of "denatured" fibrinogen that spontaneously accumulate on the individual surfaces correlate closely with the extent of biomaterial-mediated inflammation. These results suggest that surfaces that tend to "irreversibly" bind fibrinogen prompt greater acute inflammatory responses. Unexpectedly, all test surfaces except those bearing a siloxyl group engender relatively similar biomaterial-mediated fibrotic responses. Thus surface functionalities alone may not be sufficient to affect subsequent fibrotic responses.

Establishing an aminoglycoside pharmacokinetic monitoring service in a community hospital.

A pharmacy-based aminoglycoside pharmacokinetic monitoring service is described, including the use of serum gentamicin levels before and after the service. A retrospective drug and serum level use review for i.v. gentamicin treatment of 80 patients during an 11-month period was conducted. It established a need for a pharmacokinetic monitoring service, which was first instituted as a six-month pilot program. Twenty patients in the retrospective review had 43 serum levels obtained for an average of 2.2 levels per patient. In comparison, 39 patients in the pilot program had 243 serum levels drawn for an average of 6.2 levels per patient. Only six (14%) of the serum levels were obtained correctly and used appropriately in the review, compared with 231 (95%) in the pilot program (p less than 0.0001). It is concluded that the method used in establishing this service is a satisfactory approach for pharmacists who wish to convince administrators and medical staff of the need for pharmacokinetic consultation.