The conserved HR domain of the Drosophila suppressor 2 of zeste [Su(z)2] and murine bmi-1 proteins constitutes a locus-specific chromosome binding domain.

The related Drosophila Suppressor 2 of zeste [Su(z)2] and Posterior sex combs (Psc) proteins are both locus-specific chromosome binding proteins. They are found at many of the same polytene chromosome loci as other Polycomb-group proteins. The 1,365 amino acid Su(z)2 protein and the 1,603 amino acid Psc protein share a conserved 200 amino acid domain, the homology region (HR). To identify the protein domain responsible for locus-specific chromosome binding, we made a series of Hsp70:cDNA deletion constructs of the Sz(z)2 gene and transformed these into flies. We found that the HR is necessary and sufficient for Su(z)2 locus-specific polytene chromosome binding. The murine Bmi-1 protein also shares the conserved HR domain. When expressed in flies, the Bmi-1 protein showed a locus-specific chromosome binding pattern similar to that of the Su(z)2 and Psc proteins. These results argue that a locus-specific chromosome binding function resides in the HR domain. Other results show that a second, low affinity, non-specific chromosome binding function is localized outside the HR in the Su(z)2 protein, and that the Su(z)2 protein contains at least two nuclear localization signals.

The Drosophila tissue polarity gene inturned acts cell autonomously and encodes a novel protein.

Mutations in the inturned (in) gene result in abnormal wing hair polarity and in many wing cells forming two or more hairs instead of the normal single hair. We have generated genetic mosaics in a number of different experiments and find that the in gene is required in all regions of the wing and that it functions in a cell autonomous fashion. We report the molecular cloning of the in gene, the molecular mapping of in mutations and the isolation and sequencing of an in cDNA clone. The in gene encodes a novel protein whose sequence suggests it will be membrane bound. The ability of an in cDNA, the expression of which is driven by the basal activity of the hsp70 promoter to rescue an in mutation suggests that patterned expression of in is unlikely to play a role in the function of the gene.

In vivo assay for protein-protein interactions using Drosophila chromosomes.

The ability of a chimeric HP1-Polycomb (Pc) protein to bind both to heterochromatin and to euchromatic sites of Pc protein binding was exploited to detect stable protein-protein interactions in vivo. Previously, we showed that endogenous Pc protein was recruited to ectopic heterochromatic binding sites by the chimeric protein. Here, we examine the association of other Pc group (Pc-G) proteins. We show that Posterior sex combs (Psc) protein also is recruited to heterochromatin by the chimeric protein, demonstrating that Psc protein participates in direct protein-protein interaction with Pc protein or Pc-associated protein. In flies carrying temperature-sensitive alleles of Enhancer of zeste[E(z)] the general decondensation of polytene chromosomes that occurs at the restrictive temperature is associated with loss of binding of endogenous Pc and chimeric HP1-Polycomb protein to euchromatin, but binding of HP1 and chimeric HP1-Polycomb protein to the heterochromatin is maintained. The E(z) mutation also results in the loss of chimera-dependent binding to heterochromatin by endogenous Pc and Psc proteins at the restrictive temperature, suggesting that interaction of these proteins is mediated by E(z) protein. A myc-tagged full-length Suppressor 2 of zeste [Su(z)2] protein interacts poorly or not at all with ectopic Pc-G complexes, but a truncated Su(z)2 protein is strongly recruited to all sites of chimeric protein binding. Trithorax protein is not recruited to the heterochromatin by the chimeric HP1-Polycomb protein, suggesting either that this protein does not interact directly with Pc-G complexes or that such interactions are regulated. Ectopic binding of chimeric chromosomal proteins provides a useful tool for distinguishing specific protein-protein interactions from specific protein-DNA interactions important for complex assembly in vivo.

Image transfer by mutually pumped phase conjugators.

Cross talk is observed during the transient time of the photorefractive grating formation in a mutually pumped phase conjugator. We show that this feature can be used to transfer pictorial information from one location to another. The transfer is instantaneous and is demonstrated at a resolution of 6 lines/mm.

Edge enhancement of a phase-conjugate image with a mutually pumped phase conjugator.

Usually edge enhancement of optical images is produced by introduction of loss into the low spatial frequency components of the image-bearing beam in the Fourier plane of a lens. We report on edge-enhanced phase-conjugate images from a mutually pumped conjugator accomplished by spatial filtering in the Fraunhofer diffraction region of the input beams. High-resolution (128-160 lines/mm) edge-enhanced images are obtained through traditional spatial filtering in the Fourier plane and in the Fraunhofer regime. Amplification of these edge-enhanced images is observed with some loss of high spatial resolution (50 lines/mm).

Risk factors for leg ulcer recurrence: a randomized trial of two types of compression stocking.

Patients with recently healed leg ulceration were entered into a study of leg ulcer recurrence. In all, 188 patients [69% women, mean age = 72 (SD = 12) years] were entered into the study, of whom 166 were considered suitable for ready-made stockings and were randomized to one of two class II below-knee compression stockings and followed for at least 18 months. The remaining patients required either made-to-measure stockings (5) or could not tolerate stockings owing to friable skin and were treated by other methods (17). Overall cumulative recurrence rate was 26% after 1 year and 31% at 18 months. Independent risk factors for (RR = 2.34, p = 0.021) and unsuitability for stockings (RR = 2.52, p = 0.013). The randomized groups had similar stockings, 25 (15%) could not put their stockings on at all and 43 (26%) were only able to put them on with great difficulty. The two stocking types differed significantly in this regard when analysed for trend.

High-resolution phase-conjugate imaging in double-pumped phase conjugators.

Phase-conjugate images with a resolution greater than 250 lines/mm are obtained through the use of a bridge, double-pumped phase conjugator. We demonstrate that this conjugator can carry out imageprocessing tasks, such as the addition and subtraction of complex spatial distributions, with a spatial resolution of >100 lines/mm. These results represent a significant improvement over previously reported resolutions obtained from photorefractive mutually pumped phase conjugators and approach the theoretical limit imposed by the grating spacing and cross talk.

Directed overexpression of suppressor 2 of zeste and Posterior Sex Combs results in bristle abnormalities in Drosophila melanogaster.

Three dominant second-chromosome rearrangement mutations in Drosophila melanogaster, Aristapedioid1 (Arp), vestigial-Depilate (vgD), and vestigial62 (vg62), result in developmental abnormalities of the bristle sense organs on the notum, abdomen, legs, and wing margin. The bristle abnormalities are associated with overexpression of Suppressor 2 of zeste (Su(z)2). We constructed and transformed into flies Hsp70:cDNA constructs for Su(z)2 and the related and neighboring Polycomb group (Pc-G) gene Posterior Sex Combs (Psc). Heat shock-induced overexpression of these two genes (hs-Su(z)2 and hs-Psc) resulted in similar bristle abnormalities that in a developmental stage-specific manner mimicked those seen with the three rearrangement mutations. In addition, hs-Psc overexpression at white prepupae was lethal. The bristle abnormalities are reminiscent of those seen with reduced function of Notch, a neurogenic gene. We found that hs-Su(z)2 overexpression reduced the expression of a lac z enhancer trap in the neurogenic gene neuralized. Previous experiments found that loss of function mutations in Su(z)2 resulted in no bristle abnormalities. Analysis of Psc mitotic clones revealed no essential function of Psc in bristle development. Antibody staining of salivary gland polytene chromosomes showed that after heat shock induction of hs-Psc, Psc protein binds ectopically to hundreds of polytene chromosome loci. These data suggest that the bristle abnormalities seen with overexpression of Su(z)2 and Psc may result from altered expression of genes involved in bristle sense organ development that are not normal regulatory targets of these genes.

Mutually pumped phase conjugator as a moving-object correlator.

Cross talk is observed in a photorefractive bridge mutually pumped phase conjugator during the transient time of photorefractive grating formation and is utilized to construct a moving-object correlator. The correlation of various input images has been demonstrated and compared with calculated results. The device is currently capable of a resolution of approximately 4 to 6 lines/mm.

Serotonin-induced contractility in human saphenous vein is inhibited by naftidrofuryl.

Vascular endothelial denudation contributes to vasospasm by causing platelet aggregation and the subsequent release of vasoconstrictors such as serotonin. It has recently been suggested that naftidrofuryl fumarate (NFT) may oppose serotonin-induced vasoconstriction. Fourteen rings of human saphenous vein from 14 patients undergoing varicose vein surgery were tested in standard organ bath experiments. Cumulative dose-response curves and maximal contraction in response to serotonin were recorded and this was repeated in the presence of NFT at 10(-6) and 10(-3) mol/l. The difference in maximal contractility between the three sets of curves was significant (P < 0.0001). Sensitivity to serotonin in each of the three curves was measured using the concentration for half-maximal response; differences were again significant (P < 0.0001). It is concluded that NFT reduces serotonin-induced contractility in a dose-dependent fashion in rings of human saphenous vein in vitro. These results suggest a possible role for NFT in reducing vasospasm and support further investigation of this drug.

Physical symptoms of combination biotherapy: a quality-of-life issue.

Data are available on the principal side effects of individually administered biological response modifiers (BRMs). However, studies on physical symptoms secondary to multiagent regimens (i.e., combinations of BRMs and of BRMs and chemotherapy) are just now appearing in the literature. The combinations of alpha interferon and 5-FU and of alpha interferon and interleukin-2 (IL-2) are the focus of this paper. Published and unpublished reports of side effects associated with these combinations are reviewed, and resulting quality-of-life (QOL) issues examined. Physical side effects that may affect QOL are flu-like symptoms, gastrointestinal (GI) toxicities, and fatigue, which may alter social, physiological, and psychological function and negatively influence the perception of QOL. Nursing interventions to improve these reactions include awareness and assessment of the patient's perception of QOL and strategies to alleviate the symptoms. Numerous opportunities exist for nursing research on improved symptom management and on QOL in combination biotherapy regimens.

Improved photorefractive time response using a cylindrical lens.

Experimental observations are reported which demonstrate that the response time for beam fanning, self-pumped phase conjugation, and double phase conjugation can be shortened by more than an order of magnitude without a significant reduction in coupling strength by using a cyclindrical lens to focus incident laser light into a photorefractive crystal. These results are compared with those obtained using a spherical lens where a reduction in the photorefractive response time is accompanied by a corresponding reduction in coupling strength. It is shown that the fidelity of a phase conjugate beam is not degraded when cylindrical optics are used.

Nursing care of patients receiving activated lymphocytes.

Activated lymphocytes are administered to patients as a component of many biological therapy clinical trials. Oncology nurses caring for these patients need to understand administration techniques, potential side effects, and management strategies. Activated lymphocytes may be administered intravenously or regionally; administration techniques and side effects differ depending on the route of administration. The major side effects with intravenous infusion are chills/rigors, fever, hypotension, tachycardia, respiratory compromise, headache, nausea, and vomiting. When activated lymphocytes are infused regionally, the most common side effects are immediate regional discomfort and delayed chills, fever, and hypotension. Management of these side effects involves intense nursing care including assessment, monitoring, and interventions to promote medical stability and symptom control. Astute assessment skills and sound nursing judgement are essential for the safe administration of activated lymphocytes.

Self-pumped phase conjugation with nanosecond pulses in strontium barium niobate.

We report the observation of self-pumped phase conjugation by means of internal reflection in a photorefractive medium produced by a series of intense nanosecond pulses. Nanosecond pulses from a YAG laser ranging in intensity from 9 x 10(4) to 9 x 10(5) W/cm(2) were used. The crystal was rhodium-doped strontium barium niobate. The conjugate signal began with the first pulse, and the time to reach 63% of its equilibrium value scaled as I(-2). The equilibrium reflectivity was 29%. A similar cw experiment with the 514-nm line of an argon laser produced a response time that scaled as I(-1.1).

Double phase conjugation in tungsten bronze crystals.

In this paper we report a new method for double phase conjugation particularly suited to the tungsten bronze crystal strontium barium niobate. It has also been observed to produce conjugate waves in BaTiO(3) and BSKNN. This new arrangement is called the bridge conjugator because the two beams enter opposing [100] crystal faces and fan together to form a bridge without reflection off a crystal face. Our measurements indicate that the bridge conjugator is competitive with previously reported double phase conjugate mirrors in reflectivity, response time, ease of alignment, and fidelity.

Enhanced photorefractive beam fanning due to internal and external electric fields.

Significant increases (x10) in both speed and gain of the beam fanning process were obtained via three different methods in SBN and BSKNN. These methods involve the creation of a dc electric field either (1) externally, (2) by the pyroelectric effect, or (3) by thermally cycling the crystal and the presence of laser radiation. The enhanced effects were observed for both ordinary and extraordinary polarized light.

Time response of a cerium-doped Sr(0.75)Ba(0.25)Nb(2)O(6) self-pumped phase-conjugate mirror.

Self-pumping in cerium-doped strontium barium niobate has been observed with phase-conjugate reflectivities near 6% and a formation time of 8 sec for a 200-mW/cm(2)beam at 442 nm. The time response for asymmetrical self-defocusing was also measured, and the observed transmissions through the crystal at normal incidence were limited to about 1.5% of the incident radiation.