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A L Miller

Publications and source records attributed to A L Miller.

At least 19 recordsLinked to original sources
PubMed2006

Nuclear translocation of the calcium-binding protein ALG-2 induced by the RNA-binding protein RBM22.

By yeast two-hybrid screening using the calcium-binding protein ALG-2 as bait a new target of ALG-2 was identified, the RNA-binding protein RBM22. In order to confirm these interactions in vivo we prepared fluorescent constructs by using the monomeric red fluorescent protein to label ALG-2 and the enhanced green fluorescent protein to label RBM22. Confocal microscopy of NIH 3T3 cells transfected with either ALG-2 or RBM22 expression constructs encoding fluorescent fusion proteins alone revealed that the majority of ALG-2 was localized in the cytoplasm whereas RBM22 was located in the nucleus. When cells were co-transfected with expression vectors encoding both fusion proteins ALG-2 was found in the nucleus indicating that RBM22 which can shuttle between the cytoplasm and the nucleus may play a role in nuclear translocation of ALG-2. Using zebrafish as a model mRNA homologues of ALG-2 and RBM22 were microinjected into the blastodisc-yolk margin of zebrafish embryos at the 1-cell stage followed by monitoring the fusion proteins during development of the zebrafish. Hereby, we observed that ALG-2 alone evenly distributed within the cell, whereas in the presence of RBM22 the two proteins co-localized within the nucleus. More than 95% of the two proteins co-localized within the same area in the nucleus suggesting a functional interaction between the Ca(2+)-signaling protein ALG-2 and the RNA-binding protein RBM22.

Active Transport, Cell Nucleus↗
PubMed2004

Identification of genes leading to glucocorticoid-induced leukemic cell death.

Glucocorticoidal steroids (GC) are capable of causing apoptotic death of many varieties of lymphoid cells; consequently, GC are used in therapy for many lymphoid malignancies. Gene transcription in the GC-treated cells is required for subsequent apoptosis, but only a few of the actual genes involved have been identified. We employed gene microarray analysis to find the network of genes involved in GC-evoked cell death, using three clones derived from the CEM lymphoid leukemia cell line. Clone C1-15 was resistant to GC-evoked apoptosis, although not necessarily to GC-induced gene transcription; the other two underwent apoptosis in the presence of GC. Clone C7-14 was subcloned from the apoptosis-sensitive parental C7 clone to establish karyotypic uniformity. The second sensitive clone, C1-6, was a spontaneous revertant from parental resistant clone C1. A period of > or = 24 h in the constant presence of receptor-occupying concentrations of synthetic GC dexamethasone (Dex) was necessary for apoptosis to begin. To identify the steps leading to this dramatic event, we identified the changes in gene expression in the 20-h period preceding the onset of overt apoptosis. Cells in the log phase of growth were treated with 10(-6) M Dex, and 2-20 h later, mRNA was prepared and analyzed using the Affymetrix HG_U95Av2 chip, containing probes for about 12,600 genes. Of these, approximately 6,000 were expressed above background. Comparisons of the basal and expressed genes in the three clones led to several conclusions: The Dex-sensitive clones shared the regulation of a limited set of genes. The apoptosis-resistant clone C1-15 showed Dex effects on a largely different set of genes. Promoter analysis of the regulated genes suggested that primary gene targets for GC often lack a classic GC response element.

Animals↗
PubMed2003

Coordination between donor cell type and cell cycle stage improves nuclear cloning efficiency in cattle.

Several studies have shown that both quiescent and proliferating somatic donor cells can be fully reprogrammed after nuclear transfer (NT) and result in viable offspring. So far, however, no comparative study has conclusively demonstrated the relative importance of donor cell cycle stage on nuclear cloning efficiency. Here, we compare two different types of bovine fetal fibroblasts (BFFs) that were synchronized in G(0), G(1), and different phases within G(1). We show that for non-transgenic (non-TG) fibroblasts, serum starvation into G(0) results in a significantly higher percentage of viable calves at term than synchronization in early G(1) or late G(1). For transgenic fibroblasts, however, cells selected in G(1) show significantly higher development to calves at term and higher post-natal survival to weaning than cells in G(0). This suggests that it may be necessary to coordinate donor cell type and cell cycle stage to maximize overall cloning efficiency.

Animals↗
PubMed2003

Cloned cattle derived from a novel zona-free embryo reconstruction system.

As the demand for cloned embryos and offspring increases, the need arises for the development of nuclear transfer procedures that are improved in both efficiency and ease of operation. Here, we describe a novel zona-free cloning method that doubles the throughput in cloned bovine embryo production over current procedures and generates viable offspring with the same efficiency. Elements of the procedure include zona-free enucleation without a holding pipette, automated fusion of 5-10 oocyte-donor cell pairs and microdrop in vitro culture. Using this system, zona-free embryos were reconstructed from five independent primary cell lines and cultured either singularly (single-IVC) or as aggregates of three (triple-IVC). Blastocysts of transferable quality were obtained at similar rates from zona-free single-IVC, triple-IVC, and control zona-intact embryos (33%, 25%, and 29%, respectively). In a direct comparison, there was no significant difference in development to live calves at term between single-IVC, triple-IVC, and zona-intact embryos derived from the same adult fibroblast line (10%, 13%, and 15%, respectively). This zona-free cloning method could be straightforward for users of conventional cloning procedures to adopt and may prove a simple, fast, and efficient alternative for nuclear cloning of other species as well.

Animals↗
PubMed2002

Effects of follicular size of cytoplast donor on the efficiency of cloning in cattle.

In cattle, oocytes obtained from follicles smaller than 3 mm in diameter can undergo maturation in vitro, progressing to MII and undergoing fertilization, but are developmentally incompetent. Cytoplasts were prepared from in vitro matured oocytes aspirated from small (1-3 mm) or large (6-12 mm) follicles and fused to serum starved mural granulosa cells. Following activation, reconstructed embryos were cultured for 7 days and classified G1 to G4, before being processed for nuclei counting or transferred to synchronized recipients. Oocytes from small follicles had lower rates of polar body extrusion (59.6 vs. 69%; 731/1230 vs. 608/857) and fusion (71.4 vs. 78.8%; 360/497 vs. 364/465; P < 0.06). There were no differences in total rate of blastocysts development (60 vs. 59.8%; small vs. large), or any grade classification. A significant interaction was detected between follicle size and embryo grade with G3 embryos from small follicles having a greater cell number. Developmental competence of G1 and G2 embryos did not differ at day 27 (48 vs. 46%; 16/33 vs. 17/37; small vs. large). Although there were no differences in fetal size between the two groups, differences in allantois length (53 vs. 86 mm; small vs. large; P < 0.002) and allantois width (9.5 vs. 13 mm; small vs. large; P < 0.06) were seen. No differences in survival to term (2/13 in each group) were observed. These results indicate that cytoplasts from follicles of 1-3 and 6-12 mm in diameter are equally developmentally competent when used in a nuclear transfer procedure.

Animals↗
PubMed2001

The Abl-related gene (Arg) nonreceptor tyrosine kinase uses two F-actin-binding domains to bundle F-actin.

Abl family nonreceptor tyrosine kinases regulate cellular morphogenesis and motility through functional interactions with the actin cytoskeleton. Although Abl family kinases are known to contain filamentous (F)-actin-binding domains at their C termini, it is unclear how Abl family kinases regulate the structure and/or function of the actin cytoskeleton. We show here that the Abl-related kinase Arg binds with positive cooperativity to F-actin in vitro with binding saturating at a ratio of one Arg/two actin molecules. Measurements of the F-actin-binding properties of Arg deletion mutants led to the identification of a second, previously uncharacterized internal F-actin-binding domain in Arg. Purified Arg can bundle F-actin in vitro, and this bundling activity requires both F-actin-binding domains. An Arg-yellow fluorescent protein fusion protein can induce the formation of actin-rich structures at the lamellipodia of Swiss 3T3 fibroblasts. Both of Arg's F-actin-binding domains are necessary and sufficient for the formation of these actin-rich structures. Together, our data suggest that Arg can use its F-actin-bundling activity to directly regulate actin cytoskeletal structure in vivo.

3T3 Cells↗
PubMed2001

Effects of chronic stimulation on auditory nerve survival in ototoxically deafened animals.

For almost 10 years, chronic stimulation has been known to affect spiral ganglion cell (SGC) survival in the deaf ear. However, the reported effects of chronic stimulation vary across preparations and studies. In this review, the effects of chronic stimulation on the deafened auditory periphery are examined, and variables that may impact on the efficacy of chronic stimulation are identified. The effects of deafening on the unstimulated peripheral and central auditory system are also described, as the deafened, unstimulated system is the canvas upon which stimulation-mediated effects are imposed. Discrepancies in the effects of chronic stimulation across studies may be attributable in large part to the combined effects of the deafening method and the post-deafening delay prior to chronic stimulation, which vary across studies. Emphasis is placed on the need to consider the natural progression of SGC loss following deafening in the absence of chronic stimulation, as the rate of SGC loss almost certainly affects both the efficacy of stimulation, and the impact of any delay between deafening and initiation of stimulation. The differences across preparations complicate direct comparison of protective efficacy of stimulation. At the same time, these differences can be used to our advantage, aiding characterization of the effects of different factors on the efficacy of chronic stimulation as a neuroprotective intervention.

Animals↗
PubMed2001

Cochlear implant thresholds: comparison of middle latency responses with psychophysical and cortical-spike-activity thresholds.

The electrically evoked middle latency response (EMLR) is a potentially useful measure of activation of the auditory system by a cochlear prosthesis. The present study compared cochlear prosthesis thresholds determined using EMLR with thresholds determined for psychophysical detection and for spike activity in cortical neurons. In systemically deafened guinea pigs, the difference between EMLR and psychophysical threshold level varied, with differences ranging from -4.6 dB (EMLR threshold more sensitive) to +10.7 dB (psychophysical threshold more sensitive) across animals and phase durations. Threshold differences between EMLR and auditory cortex neural spike responses were similar in magnitude and range (-6 to +15 dB) to those seen for EMLR vs. psychophysical thresholds. These ranges are comparable to the behavioral operating range for a given condition. In 3 of 12 subjects, the EMLR was absent for some or all electrode configurations tested, even at levels well above the threshold for psychophysical detection or cortical neuronal response. These results suggest that neither the EMLR thresholds nor cortical neuronal spike thresholds are an adequate substitute for psychophysical measures of threshold. While not sufficient for use in place of psychophysical measures, EMLR threshold level is strongly correlated with psychophysical threshold level across subjects (R(2)=0.82). Interestingly, plots of thresholds vs. phase duration were roughly parallel for psychophysical and EMLR thresholds, in contrast to the divergence of psychophysical and more peripheral (e.g., electrically evoked auditory brainstem response) evoked neural threshold vs. phase duration functions.

Action Potentials↗
PubMed2001

Which side effects really matter? Screening for common and distressing side effects of antipsychotic medications.

As a class, the newer antipsychotics are less likely to cause EPS but continue to have a range of other, non-EPS, side effects. Most standardized scales for side effects of antipsychotics emphasize the physical findings of the motor abnormalities of extrapyramidal symptoms (EPS). There is a need for screening instruments that include both EPS and non-EPS side effects. This article discusses the development of a screening instrument called the Approaches to Schizophrenia Communication (ASC). Initially derived from other subjective screening measures, the ASC was specifically designed to address the following issues pertaining to side effect evaluation of antipsychotics: 1) to cover all common and distressing side effects from antipsychotics, not just EPS, and 2) to screen for perceived distress, rather than the objective severity of the side effect. These two characteristics of the ASC make it possible for it to be given directly to the patient (the ASC Self-Report Version) or to be administered by mental health clinicians who do not have to be extensively trained in side-effect assessments (the ASC Clinician Interview version).

Journal Article↗
PubMed2001

Evidence-based pharmacologic treatment for people with severe mental illness: a focus on guidelines and algorithms.

Medication treatment of severe mental illness has been advanced and complicated by the introduction of numerous therapeutic agents. Practice guidelines based on research evidence have been developed to help clinicians make complex decisions. Studies of usual care suggest an important potential role for guidelines in improving the quality of medication treatment for people with severe mental illness. The authors review current evidence-based guidelines for medication treatment of persons with severe mental illness. Four categories of guidelines are described: recommendations, comprehensive treatment options, medication algorithms, and expert consensus. The authors note that more research is needed on optimal next-step strategies and the treatment of patients with comorbidity and other complicating problems. They discuss barriers to the implementation of guidelines, and they observe that the potential of guidelines and algorithms to promote evidence-based medication treatment for persons with severe mental illness depends on refinement of tools, progress in research, and cooperation of physicians, nonphysician clinicians, administrators, and consumers and family members.

Depressive Disorder↗
PubMed2001

The etiologies, pathophysiology, and alternative/complementary treatment of asthma.

A chronic inflammatory disorder of the respiratory airways, asthma is characterized by bronchial airway inflammation resulting in increased mucus production and airway hyper-responsiveness. The resultant symptomatology includes episodes of wheezing, coughing, and shortness of breath. Asthma is a multifactorial disease process with genetic, allergic, environmental, infectious, emotional, and nutritional components. The underlying pathophysiology of asthma is airway inflammation. The underlying process driving and maintaining the asthmatic inflammatory process appears to be an abnormal or inadequately regulated CD4+ T-cell immune response. The T-helper 2 (Th2) subset produces cytokines including interleukin-4 (IL-4), IL-5, IL-6, IL-9, IL-10, and IL-13, which stimulate the growth, differentiation, and recruitment of mast cells, basophils, eosinophils, and B-cells, all of which are involved in humoral immunity, inflammation, and the allergic response. In asthma, this arm of the immune response is overactive, while Th1 activity, generally corresponding more to cell-mediated immunity, is dampened. It is not yet known why asthmatics have this out-of-balance immune activity, but genetics, viruses, fungi, heavy metals, nutrition, and pollution all can be contributors. A plant lipid preparation containing sterols and sterolins has been shown to dampen Th2 activity. Antioxidant nutrients, especially vitamins C and E, selenium, and zinc appear to be necessary in asthma treatment. Vitamins B6 and B12 also may be helpful. Omega-3 fatty acids from fish, the flavonoid quercetin, and botanicals Tylophora asthmatica, Boswellia serrata and Petasites hybridus address the inflammatory component. Physical modalities, including yoga, massage, biofeedback, acupuncture, and chiropractic can also be of help.

Air Pollution↗
PubMed2000

Calcium signalling during zebrafish embryonic development.

Calcium signals appear throughout the first 24 hours of zebrafish development. These begin at egg activation, then continue to be generated throughout the subsequent zygote, cleavage, blastula, gastrula, and segmentation periods. They are thus associated with the major phases of pattern formation: cell proliferation, cell differentiation, axis determination, the generation of primary germ layers, the emergence of rudimentary organ systems, and therefore the establishment of the basic vertebrate body plan. When signals need to be transmitted across significant distances they take the form of waves, either intracellular waves when the cell size is large, or later in development when the cell size is reduced, intercellular waves. We will consider both types of calcium signals and their integration into signalling networks, and discuss their possible functions and developmental significance with regard to pattern formation. BioEssays 22:113-123, 2000.

Animals↗
PubMed2000

Youth suicidal behavior: assessment and intervention.

In this article, the authors review the research on risk assessment of suicidal adolescents and describe the small body of randomized-clinical-treatment trials for this population. Research has yielded a fairly consistent set of direct and indirect risk factors for suicidal behavior in adolescents. The authors describe a variety of measures commonly used to assess these risk factors. Treatment studies targeting suicide are sparse for all ages. In the adult literature, evidence suggests clozapine, depot flupenthixol, lithium, and dialectical behavior therapy (DBT) are significantly more effective in decreasing suicidal behavior than placebo or Treatment as Usual. For adolescents, it is difficult to draw conclusions about treatment efficacy. In general, control conditions are just as effective at reducing suicidal behavior as experimental conditions. While some novel interventions for suicidal adolescents are described, there is a desperate need for more research to be conducted in order to advance this burgeoning field.

Adolescent↗
PubMed2000

MACI personality scale profiles of depressed adolescent suicide attempters: a pilot study. Million Adolescent Clinical Inventory.

Employing the Millon Adolescent Clinical Inventory (MACI), we examined differences in the maladaptive personality style profiles of clinically referred, depressed adolescents presenting with (n = 26) and without (n = 23) a history of previous suicide attempts. Relative to the comparison group, adolescent attempters experienced more severe overall levels of personality dysfunction. At the trait level, attempters obtained higher scores on the forceful and borderline tendency scales and lower scores on the submissive and conforming scales of the MACI, reflecting negative mood regulation deficits (e.g., anger control problems) and persistently high levels of aggressive impulsivity. These preliminary findings suggest that MACI personality scales may be useful in discriminating adolescents with and without previous suicidal behavior, especially among depressed outpatient samples.

Adolescent↗
PubMed2000

Evidence-based treatment of schizophrenia.

People with schizophrenia can be helped greatly with pharmacologic and psychosocial interventions that are known to be effective. Several interventions are now supported by research: use of medications following specific guidelines, training in illness self-management, case management based on principles of assertive community treatment, family psychoeducation, supported employment, and integrated substance abuse treatment. However, few patients actually receive these evidence-based interventions because they are not provided in routine mental health settings. Therefore, implementing effective treatments in mental health treatment programs is a critical challenge for the field. We review the six areas of evidence-based treatment of schizophrenia, as well as knowledge regarding implementation of mental health programs in routine practice settings.

Antipsychotic Agents↗
PubMed2000

Effects of time after deafening and implantation on guinea pig electrical detection thresholds.

Changes in detection threshold level as a function of time after deafening and implantation have been described previously in macaque [Pfingst, 1990] and human [Skinner et al., 1995] cochlear implant subjects. Characterization of the mechanisms underlying these changes will contribute to our understanding of the anatomical and physiological factors affecting electrical stimulus detection. In addition, understanding the time course of early threshold changes is essential to the interpretation of acute physiological studies of cochlear implants. To better characterize time-dependent threshold changes, we monitored changes in guinea pig psychophysical electrical detection thresholds with time after deafening and cochlear implantation. Threshold levels for 100 Hz sinusoidal bursts were initially unstable over the first 30 days post-surgery (DPS), after which thresholds stabilized. At longer intervals (>100 DPS), increases (>10 dB) in threshold level were observed for 100 Hz sinusoids in three of 11 cases. These changes were transient in one case and long-term in two cases. The time course of threshold change, both early and late, could not be explained on the basis of changes in spiral ganglion cell survival. The guinea pig seems to be an ideal preparation for studies of this nature, because threshold changes are similar in type, but accelerated in time course, relative to those observed in primates.

Animals↗