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D Morris

Publications and source records attributed to D Morris.

At least 37 records · Page 2Linked to original sources
PubMed1998

Phylogenetics of social behavior in Australian gall-forming thrips: evidence from mitochondrial DNA sequence, adult morphology and behavior, and gall morphology.

Six species of Australian gall-forming thrips (Insecta: Thysanoptera) on Acacia exhibit soldier castes, individuals with reduced wings and enlarged forelegs that defend their gall against interspecific invaders. We used data from two mitochondrial genes (cytochrome oxidase I and 16S rDNA), adult morphology and behavior, and gall morphology to infer a phylogeny for Acacia gall-forming thrips with and without soldiers, and we used this phylogeny to evaluate hypotheses concerning soldier evolution. Phylogenies inferred from each data set analyzed separately yielded large numbers of most-parsimonious trees and weak support for most nodes. However, when analyzed together the data sets complemented and reinforced one another in such a way as to yield a well-resolved phylogeny. Our phylogeny implies that soldiers originated once or twice early in the history of this clade, that soldiers were lost once or twice, and that soldiers evolved from winged dispersers rather than from nonsoldier within-gall reproductive offspring of foundresses. The phylogeny also provides evidence for long-term morphological stasis, an ancient split between eastern and western gall thrips species, and a high degree of conservatism in host-plant affiliations.

Acacia↗
PubMed1998

Extended spectrum beta-lactamase production and fluorquinolone resistance in pathogens associated with community acquired urinary tract infection.

We have evaluated the susceptibility of 199 pathogens isolated in pure culture from consecutive urine samples submitted from the community. Rates of susceptibility for all organisms were ampicillin, 48%; amoxycillin/clavulanic acid, 88%; cephalothin, 57%; cefuroxime axetil, 74%; nalidixic acid, 85%; ciprofloxacin, 99%; nitrofurantoin, 78%; and trimethoprim, 67%. Ciprofloxacin resistance and production of extended spectrum beta-lactamase enzymes were detected in Escherichia coli strains isolated from patients in the community.

Anti-Infective Agents↗
PubMed1998

Health problems and health actions among community-dwelling older adults: results of a health diary study.

This study examined the health problems and health actions reported by a sample of older adults (N = 60) who maintained health diaries over a 4-week period. The diary sample was 78% (n = 47) White; 52% (n = 31) were women, with a mean age of 75 years (SD = 5.3). Content analysis was used to examine the types of health problems reported in the diaries, which health problems were likely to be considered an illness, and what health actions were reported. Respondents reported an average of four different types of health problems over the 4-week diary period. There were differences in symptom reports related to gender, age, or race. The most frequently reported health problems were musculoskeletal problems (n = 38), runny nose and respiratory problems (n = 24), gastrointestinal problems (n = 22), and headaches (n = 22). Only 36% of all health problems were considered to be illnesses. Subjects recorded a number of health actions in response to their health complaints, including over-the-counter (OTC) medication use (83%), prescription medication use (53%), self-care activities (72%), and professional consultation (43%). Specific strategies that subjects used to deal with various health problems, implications of the findings, and the usefulness of health diaries as a clinical tool are discussed.

Aged↗
PubMed1997

The active site region of the vitamin K-dependent carboxylase includes both the amino-terminal hydrophobic and carboxy-terminal hydrophilic domains of the protein.

In order to localize the active site of the vitamin K-dependent carboxylase, we developed an affinity probe containing the propeptide and the first two carboxylatable glutamate residues conserved in many native substrates. This probe crosslinked to both the hydrophobic amino-terminal and hydrophilic carboxy-terminal domains of the carboxylase, in contrast with previous work which localized both the catalytic and the propeptide binding site within the amino-terminal hydrophobic domain. Amino acid analysis revealed that the mass of an amino-terminal fragment is seriously underestimated by SDS-PAGE. Reanalysis of the published data in light of this information suggests that a portion of the propeptide binding site resides within the carboxy-terminal hydrophilic domain.

Amino Acid Sequence↗
PubMed1997

Fish consumption and the 30-year risk of fatal myocardial infarction.

BACKGROUND: Epidemiologic data on the possible benefit of eating fish to reduce the risk of coronary heart disease have been inconsistent. We used data from the Chicago Western Electric Study to examine the relation between base-line fish consumption and the 30-year risk of death from coronary heart disease. METHODS: The study participants were 1822 men who were 40 to 55 years old and free of cardiovascular disease at base line. Fish consumption, as determined from a detailed dietary history, was stratified (0, 1 to 17, 18 to 34, and > or = 35 g per day). Mortality from coronary heart disease, ascertained from death certificates, was classified as death from myocardial infarction (sudden or nonsudden) or death from other coronary causes. RESULTS: During 47,153 person-years of follow-up, there were 430 deaths from coronary heart disease; 293 were due to myocardial infarctions (196 were sudden, 94 were nonsudden, and 3 were not classifiable). Cox proportional-hazards regression showed that for men who consumed 35 g or more of fish daily as compared with those who consumed none, the relative risks of death from coronary heart disease and from sudden or nonsudden myocardial infarction were 0.62 (95 percent confidence interval, 0.40 to 0.94) and 0.56 (95 percent confidence interval, 0.33 to 0.93), respectively, with a graded relation between the relative risks and the strata of fish consumption (P for trend = 0.04 and 0.02, respectively). These findings were accounted for by the relation of fish consumption to nonsudden death from myocardial infarction (relative risk, 0.33; 95 percent confidence interval, 0.12 to 0.91; P for trend= 0.007). CONCLUSIONS: These data show an inverse association between fish consumption and death from coronary heart disease, especially nonsudden death from myocardial infarction.

Adult↗
PubMed1997

Depression during mania. Treatment response to lithium or divalproex.

BACKGROUND: Little information exists from controlled studies about clinical characteristics that predict treatment response in mania. The presence of depressive symptoms during manic episodes may be associated with poor response to psychopharmacological treatments. This is an investigation of the relation between depressive symptoms and treatment response in acute manic episodes. METHODS AND DESIGN: In a parallel-group, double-blind study, 179 patients hospitalized for acute manic episodes were randomized to receive divalproex sodium, lithium carbonate, or placebo (ratio, 2:1:2). The study was carried out at 9 academic medical centers. Patients had comprehensive evaluations of behavior and symptoms before and during 3 weeks of treatment. The primary outcome measure, change in mania factor scores derived from the Schedule for Affective Disorders and Schizophrenia: Change Version, was compared in patients with and without depressive symptoms at baseline according to nurse- or physician-rated scales. RESULTS: Depressive symptoms were associated with poor antimanic response to lithium and with better response to divalproex. This was not due to differences in overall severity of illness, substance abuse, gender, age, or history. CONCLUSIONS: These data suggest that even a modest level of pretreatment depression-related symptoms is a robust predictor of lithium nonresponse, and is associated with better response to divalproex. Although their overall efficacy in acute mania is similar, lithium and divalproex may be most effective in clinically and biologically distinct groups of patients.

Adult↗
PubMed1997

Effect size of efficacy measures comparing divalproex, lithium and placebo in acute mania.

Effect size (ES) is a statistical concept that can be used to improve the interpretation of results from psychopharmacological studies. ES may aid interpretation of results when sample size is unbalanced or small or when units or levels of baseline measures differ across items. Usually, an investigator can define a threshold value for a clinically meaningful ES based on published data and clinical judgment or by resorting to conventions, e.g., a medium ES = 0.5 S.D., which can usually be discerned by the trained clinician. In the present study, we apply ES analysis to results from a study comparing the effectiveness of divalproex (DIVAL), lithium (LI), and placebo (PLA) in hospitalized, acutely manic patients. One hundred seventy-six patients were randomly assigned to DIVAL, LI, or PLA in a 2:1:2 ratio, with drug administered in a double-blind, parallel group design for 21 days. The primary efficacy measure was the Mania Rating Scale from the Schedule for Affective Disorders and Schizophrenia, composed of the Manic Syndrome Score (MSS) from items that are relatively specific to the manic state, and the Behavior and Ideation Score (BIS), which reflects severe but nonspecific psychopathology. Improvement of the MSS after 5 days of treatment was difficult to interpret based on percentage change (DIVAL = 19%, LI = 13.5%, PLA = 8.5%). However, the corresponding effect sizes of 0.79, 0.55, and 0.35 indicated a medium to marked ES for DIVAL, a medium ES for LI, and a small ES for PLA at this early point in treatment. Similarly, the ES for change on the MSS at the end of treatment indicated a large, readily observable improvement with both DIVAL (ES = 1.01) and LI (ES = 0.79) vs. an ES of 0.37 for PLA. ES analysis also indicated that the BIS is a less robust indicator of change to either drug. The ES at the end of treatment for the BIS was 0.67 for DIVAL-, 0.62 for LI-, and 0.25 for PLA-treated patients.

Adolescent↗
PubMed1997

Identification and characterization of polymorphisms in the promoter region of the human Apo-1/Fas (CD95) gene.

Apo-1/Fas (CD95) is a transmembrane protein expressed on the cell surface that is involved in apoptosis and plays an important role in the function and regulation of the immune system. Aberrant expression of the Apo-1/Fas gene product has been reported in a number of immune-related disorders, such as autoimmune lymphoproliferative syndrome and systemic lupus erythematosus in humans. Mutations in the coding sequence of the Apo-1/Fas gene have been reported in the former condition, whereas no abnormalities of the gene have been found to account for the increased gene expression noted in SLE. We screened the whole 5' flanking region of the Apo-1/Fas gene encompassing over 2000 bp for mutation(s)/polymorphism(s) using multiplex PCR, single-strand conformation polymorphism (SSCP) analysis and sequencing techniques, and identified two polymorphisms in this region. The first polymorphism is a CG-->CA substitution at -1377 nucleotide position within the silencer region, which neither creates or deletes any restriction enzyme sites but alters the transcription factor SP-1 binding site. This polymorphism is noted in 20% of normal Caucasians. The second polymorphism is an GA-->GG substitution at -670 nucleotide position in the enhancer region that creates a MvaI restriction fragment length polymorphism (RFLP) and abolishes the binding site of nuclear transcription element GAS. The MvaI RFLP is polymorphic with heterozygosity of 52% and the frequency of G and A alleles are 0.49 and 0.51, respectively. The identification and characterisation of these two new polymorphisms, particularly the MvaI RFLP marker, provides new genetic markers and may prove useful for further studies on the regulation of apoptosis mediated by the Apo-1/Fas gene on human chromosome 10q23.

Apoptosis↗
PubMed1997

Coronary revascularization surgery after myocardial infarction: impact of bypass surgery on survival after thrombolysis. GUSTO Investigators. Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries.

OBJECTIVES: This study sought to investigate the impact of surgical revascularization on outcome after myocardial infarction. BACKGROUND: Small variations in rates of coronary artery bypass graft surgery (CABG) were noted among thrombolytic regimens in the Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO) trial, prompting the question of whether survival differences were partly related to differences in CABG rates. METHODS: Patients in the GUSTO trial were randomized to one of four thrombolytic strategies. Of 40,861 patients with complete data, 3,526 underwent surgical revascularization during their initial hospital admission. Thirty-day and 1-year mortality rates were estimated using Kaplan-Meier techniques, and the impact of CABG as a time-dependent covariate on death was evaluated using a Cox survival model, adjusting for baseline prognostic factors. RESULTS: The median time from study enrollment to CABG was 7 days across treatment groups. A 15% reduction in mortality for the tissue-type plasminogen activator (t-PA)-treated group was evident by the seventh day. Bypass surgery was a significant independent predictor of 30-day mortality (risk ratio 1.87) and a weaker predictor of 1-year mortality (risk ratio 1.21). Operative mortality was highest in patients with acute mitral regurgitation, ventricular septal defect or poor left ventricular function and in those undergoing CABG within the first 4 days of randomization. CONCLUSIONS: The survival benefit of accelerated t-PA was not related to surgical revascularization. Bypass surgery was associated with excess mortality in the first year, but the added short-term mortality associated with CABG may be balanced by anticipated long-term benefit in specific groups of patients.

Aged↗
PubMed1997

Nuances of aesthetic blepharoplasty.

The orbits and surrounding tissues form the emotional and expressive center of the human face. Eye contact forms a large part of human interaction and, unfortunately, it is often this region that first surrenders to the aging process. A successful blepharoplasty depends on the careful evaluation of a patient's eyes, correct assessment of the cosmetic problems, and the surgical dexterity to repair such defects adequately. Consistent success may be achieved only with mastery of aesthetic consideration of the eyes, which aid in the diagnosis of the deformity of asymmetry. From that, the appropriate surgical intervention may ensue. This discussion will review the anatomy related to different orbital expressions, delineate the effects of aging, and briefly touch on techniques in our surgical armamentarium to correct and improve eyes through blepharoplasty.

Adult↗
PubMed1997

Lack of linkage between anti-nuclear antibody or clinical features of systemic lupus erythematosus (SLE) and TCR-A/Vbeta loci in families of subjects with SLE.

The role of the TCR-A and TCR-Vbeta genes in the genetic predisposition to SLE expression and anti-nuclear antibody (ANA) production were examined by linkage analysis in eighteen multiplex and forty-three simplex SLE families. All subjects were Caucasian. A significantly increased prevalence of positive ANAs in first-degree relatives of SLE patients from multiplex families was noticed compared to that of simplex families. Linkage between TCR-A/Vbeta genes and SLE expression and ANA production were analysed by affected sib-pair method. Results showed that the haplotypes identical by descent sharing TCR-A and TCR-Vbeta genes in the affected sib-pairs was not different from that expected (P = 0.93 and P = 0.74, respectively). There was no linkage between ANA positivity and TCR-A and TCR-Vbeta genes in ANA positive sib-pairs from both multiplex and simplex families. This study suggests that germline TCR-A and TCR-Vbeta gene loci confer no susceptibility to ANA and SLE expression.

Adult↗
PubMed1997

Maintenance clinical trials in bipolar disorder: design implications of the divalproex-lithium-placebo study.

Maintenance studies in bipolar disorder have received increased attention in recent years. The interest is driven by apparent contradictions between results of early placebo-controlled trials of lithium and recent open studies, as well as interest in a new group of drugs with mood-stabilizing properties. The multiple outcome indices that require attention in prophylactic bipolar disorder studies add a dimension not present in acute studies of bipolar disorder. We present the methodology of a recently completed randomized, double-blind, placebo-controlled, parallel-group comparison of divalproex and lithium. We examine the consequences of salient design features, along with their implications for future studies. A fundamental conclusion is that such maintenance studies should be designed and executed to emphasize enrollment of patients with relatively active, severe forms of the illness. This goal is not achieved simply, as inherent features of long-term, placebo-controlled studies drive recruitment and enrollment in the direction of patients with milder forms of bipolar disorder. Attention to the frequency of both manic and depressive episodes and the severity of an index manic episode may aid in the selection of patients most suitable for studies designed to achieve adequate statistical power.

Adult↗
PubMed1996

Comparisons of characteristics and outcomes among women and men with acute myocardial infarction treated with thrombolytic therapy. GUSTO-I investigators.

OBJECTIVE: To compare baseline characteristics, complications, and treatment-specific outcomes of women and men with acute myocardial infarction treated with thrombolytic therapy. DESIGN: Randomized controlled trial. PATIENTS AND SETTING: A total of 10315 women and 30706 men with acute myocardial infarction treated in 1081 hospitals in 15 countries as part of the Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO-I). INTERVENTION: One of four thrombolytic regimens: (1) streptokinase with subcutaneous heparin; (2) streptokinase with intravenous heparin; (3) streptokinase plus alteplase (tissue-type plasminogen activator) with intravenous heparin; or (4) accelerated alteplase with intravenous heparin. MAIN OUTCOME MEASURES: Mortality, stroke, and nonfatal complications during 30-day follow-up. RESULTS: Women were on average 7 years older than men and delayed 18 minutes (median) longer after symptom onset before presenting to the hospital. After adjustment for age, women more often had a history of diabetes, hypertension, and smoking than men. Time to treatment was significantly longer in women (1.2 vs 1.0 hours; P<.001). Women had more nonfatal complications after treatment, including shock (9% vs 5%; P<.001), congestive heart failure (22% vs 14%; P<.001), serious bleeding (15% vs 7%; P<.001), and reinfarction (5.1% vs 3.6%; P<.001). Women had twice as many total strokes as men (2.1% vs 1.2%; P<.001), secondary to their older age at presentation. The unadjusted mortality rate was twice as high in women as men (11.3% vs 5.5%; P<.001); the relative risk (RR) of death was greater among women than men after adjustment for differences in baseline characteristics (RR=1.15; 95% confidence interval, 1.0 to 1.31). Although women and men underwent angiography at similar rates, there were small but significant differences in their rates of revascularization procedures (angioplasty: 35% of women and 32% of men; bypass surgery: 7% of women and 9% of men; P<.001 for both). The higher rate of stroke in women after treatment with alteplase (2.0% vs 1.9% with streptokinase and intravenous heparin) was offset by a greater relative reduction in mortality (10.3% vs 11.1%). CONCLUSION: Women who received thrombolytic therapy for treatment of acute myocardial infarction were at greater risk for both fatal and nonfatal complications than men.

Aged↗
PubMed1996

Evaluation of the BCL-2 gene locus as a susceptibility locus linked to the clinical expression of systemic lupus erythematosus (SLE).

Systemic lupus erythematosus (SLE) is an autoimmune disease characterised by the production of a large number of autoantibodies. It has been postulated that this may be the result of prolonged longevity of auto-reactive B cells due to defective regulation of programmed cell death (apoptosis). The proto-oncogene bcl-2 is involved in the control of apoptosis in immunocompetent cells, and its over-expression is noted in T and B cells from SLE patients. This study examined the genetic linkage between the bcl-2 gene locus and SLE susceptibility using the affected sib-pair method in SLE families. Seventeen caucasian multiplex families were evaluated. A polymorphic microsatellite marker closely linked to the bcl-2 gene on 18q21.3 was used to determine the bcl-2 genotype. We demonstrated that haplotype sharing among the affected sibling pairs was not statistically different from random (P > 0.5). This suggests that the bcl-2 gene locus does not confer a genetic susceptibility to SLE expression.

Alleles↗