Highly anisotropic, ultra-smooth patterning of GaN/SiC by low energy electron enhanced etching in DC plasma

Hetero-epitaxial films of GaN(OOOl), deposited on SiC(OOOl) by organometallic vapor phase epitaxy and masked by 200 nm of SiO₂, have been patterned by low energy electron enhanced etching (LE4) in hydrogen and chlorine dc plasmas at room temperature. Lines 2.0 μm wide showed highly anisotropic etching: straight side walls, no overcut, no trenching, and no “pedestal” at the base of the line. Root mean square (RMS) surface roughness of the films as grown was 8.5–10?; after LE4, RMS surface roughness of the etched surfaces was 2.5?.     

Randomized study of prophylactic platelet transfusion threshold during induction therapy for adult acute leukemia: 10,000/microL versus 20,000/microL

PURPOSE: We designed and conducted a randomized single-institution trial comparing two common prophylactic platelet transfusion thresholds in patients undergoing induction therapy for acute leukemia. PATIENTS AND METHODS: Seventy-eight patients undergoing induction therapy for acute leukemia were randomized to receive prophylactic apheresis platelet concentrates when the platelet count was either < or = 10,000/microL or < or = 20,000/microL. RESULTS: There was no significant difference in the total number of bleeding episodes per patient with a median of four in the < or = 10,000/microL arm and two in the < or = 20,000/microL arm (25th to 75th percentiles of 2, 7 and 1, 5, respectively; P = .12). Patients randomized to the < or = 10,000/microL arm received more platelet transfusions for bleeding [one (0, 2) v zero (0, 0); P = .0003]. In contrast, patients on the < or = 20,000/microL arm received more platelet transfusions for prophylactic indications [10 (5, 14) v six (3, 8); P = 0.001], as would be expected, but less for bleeding. Nevertheless, the total number of platelet transfusions given to patients on the < or = 20,000/microL arm was higher and nearly significant [11 (6, 15) v seven (5, 11); P = .07]. There were no statistically significant differences between the groups with regard to RBC transfusion requirements, febrile days, days hospitalized, days thrombocytopenic, need for HLA-matched platelets, remission rate, or death during induction chemotherapy. No patient in either group died from hemorrhage or underwent major surgery for bleeding complications. CONCLUSION: Giving prophylactic platelets at a threshold of < or = 10,000/microL compared with < or = 20,000/microL can decrease the total utilization of platelets with only a small adverse effect on bleeding, and no statistically significant effect on morbidity.     

Multicomponent gene therapy vaccines for lung cancer: effective eradication of established murine tumors in vivo with interleukin-7/herpes simplex thymidine kinase-transduced autologous tumor and ex vivo activated dendritic cells

Multiple antitumor modalities may be necessary to overcome lung tumor-mediated immunosuppression and effectively treat non-small cell lung cancer (NSCLC). To evaluate a multimodality gene therapy approach for control of local tumor growth, a weakly immunogenic murine alveolar cell carcinoma, L1C2, was transduced with either the interleukin-7/hygromycin-herpes simplex thymidine kinase (IL-7/HyHSVtk) internal ribosome entry site (IRES) retroviral vector or a vector containing the HyHSVtk, but not the IL-7 gene. Of the many cytokines available for gene transfer, IL-7 was chosen for these studies because it both stimulates CTL responses and down-regulates tumor production of the immunosuppressive peptide TGF-beta. Following selection in hygromycin, IL-7 transduction was confirmed by ELISA. Clones produced 1.25 to 10 ng of IL-7/ml/10(6) cells per 24 h. In vitro, genetically modified tumor cells were significantly more sensitive to ganciclovir (GCV) than unmodified parental tumor cells. The in vivo growth of ex vivo modified L1C2 cells was evaluated. There was a dose-response relationship between the amount of IL-7 secreted in vitro and the growth of genetically modified murine tumor in vivo. Transduced tumor cells regressed in mice following GCV therapy. Although ex vivo gene modification of tumor cells led to complete resolution of the tumor following implantation in vivo, IL-7 and HSVtk gene modified tumor cells were not effective in treating established parental tumors. However when 5 x 10(5) bone marrow-derived, in vitro activated dendritic cells (DC) were administered in combination with transduced tumor and GCV, 5 day old established tumors were eradicated in 80% of mice. These studies suggest that multicomponent vaccines may facilitate improved host responses by replacing host immune deficits and thus could have a role in adjuvant therapy and local control of NSCLC.     

An A to Z guide to DSM-IV conundrums.

The work on the 4th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) poses many puzzling conundrums that touch on complicated and important theoretical and practical issues. None of these can be resolved in the DSM-IV, but the authors hope that the Task Force's decisions will be informed by thorough reviews of the currently available evidence and extensive input from all sectors of the mental health field. A. J. Frances et al provide an alphabetical guide to DSM-IV conundrums that they hope will stimulate comments, suggestions, and criticisms about the work of the Task Force. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sarcoidosis manifesting as uveitis and menometrorrhagia

PURPOSE: To report a rare systemic manifestation of sarcoidosis identified in a 47-year-old white woman while she was undergoing evaluation for bilateral recurrent uveitis. METHODS: The patient underwent clinical and laboratory evaluation for bilateral recurrent uveitis including serologic and radiologic testing, a gallium scan, and an endometrial biopsy. RESULTS: Although the serologic tests and chest x-ray were normal, the gallium scan was consistent with sarcoidosis, and the endometrial biopsy provided a tissue diagnosis. CONCLUSION: Sarcoidosis involving the female reproductive tract is rare. A thorough review of systems is crucial in the evaluation of any patient with recurrent uveitis.     

dally, a Drosophila glypican, controls cellular responses to the TGF-beta-related morphogen, Dpp

Decapentaplegic (Dpp) is a Drosophila member of the Transforming Growth Factor-beta (TGF-beta)/Bone Morphogenetic Protein (BMP) superfamily of growth factors. Dpp serves as a classical morphogen, where concentration gradients of this secreted factor control patterning over many cell dimensions. Regulating the level of Dpp signaling is therefore critical to its function during development. One type of molecule proposed to modulate growth factor signaling at the cell surface are integral membrane proteoglycans. We show here that division abnormally delayed (dally), a Drosophila member of the glypican family of integral membrane proteoglycans is required for normal Dpp signaling during development, affecting cellular responses to this morphogen. Ectopic expression of dally+ can alter the patterning activity of Dpp, suggesting a role for dally+ in modulating Dpp signaling strength. These findings support a role for members of the glypican family in controlling TGF-beta/BMP activity in vivo by affecting signaling at the cell surface.     

A simplified in vivo drug sensitivity test for malaria in the field

Using a derivative of the plasmid pBR322 we have tested the dimer catastrophe hypothesis of plasmid instability. Most of the theory was confirmed by our observations, but our data suggest that some of the quantitative aspects need modification. In a recF strain of Escherichia coli we estimated the difference in loss rate between the plasmid in the monomeric and the dimeric state to be a factor of 13-14 and the difference in the loss rate between the plasmid in the monomeric and the trimeric state to be a factor of 14-50. We were able to confirm that plasmid oligomers were heterogeneously distributed within a rec+ population, but we were unable to detect any pronounced difference in the level of growth inhibition exerted by the plasmid when in the monomeric, dimeric, or trimeric state. This leaves open the question as to whether runaway plasmid multimerization was prevented (i) by a small correlation between the inhibition of growth and the 'multimeric status' of the plasmid, (ii) by intramolecular homologous recombination, or (iii) whether the process of runaway multimerization is too slow to be recognized within the duration of the experiments, i.e. 200 generations of growth.     

Resting metabolic rate in young Polynesian and Caucasian women

OBJECTIVE: To investigate whether resting metabolic rate (RMR) differs between Caucasian and Polynesian women. DESIGN: Cross-sectional comparison. SUBJECTS: Eighty-two (42 Caucasian, 40 Polynesian) healthy women aged between 18 and 27 y. MEASUREMENTS: RMR (indirect calorimetry) and body composition (fat-free mass and fat mass derived from oxygen-18 dilution measurement of total body water). RESULTS: RMR was similar in the Caucasian (6956 +/- 1291 (s.d.) kJ/d) and Polynesian (7125 +/- 1290 kJ/d) groups while fat-free mass was significantly lower in the Caucasian group (45.3 +/- 6.8 vs 51.0 +/- 6.4 kg, P < 0.002). After adjustment for fat-free mass and fat mass, RMR was lower in the Polynesian than the Caucasian groups (6783 +/- 904 vs 7281 +/- 901 kJ/d, P = 0.023). CONCLUSION: The significantly lower relative RMR observed in Polynesian compared to Caucasian women may predispose Polynesian women to eventual onset of obesity.