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Biomedical subjects

J D Anderson

Publications and source records attributed to J D Anderson.

At least 37 records · Page 2Linked to original sources

The 24-kDa protein from Fusarium oxysporum f.sp. erythroxyli: occurrence in related fungi and the effect of growth medium on its production.

A 24-kDa protein that elicits ethylene production and necrosis in leaves of dicotyledonous plants was previously purified from culture filtrates of Fusarium oxysporum Schlechtend:Fr. f.sp. erythroxyli. Antisera to the denatured 24-kDa protein detected 2.5 ng of the 24-kDa protein on Western blots at 100000-fold dilutions. The antisera cross-reacted with a 24-kDa protein on Western blots of culture filtrates from three other F. oxysporum formae speciales. Of seven Fusarium species, only F. oxysporum, F. acuminatum Ellis and Kellerm., and F. avenaceum (Fr.:Fr.) Sacc. isolates produced an antigenically related 24-kDa protein. Although there were differences in the profiles of proteins extracted from stems of coca (Erythroxylum coca var. coca L. Lam.) infected with F. oxysporum f.sp. erythroxyli compared with uninfected stems, antisera to the 24-kDa protein did not cross-react with any proteins from the infected coca stems. For the fungal isolates studied, the best medium tested for production of the 24-kDa protein contained 1% sucrose and 1% asparagine. Biological activity of the F. oxysporum culture filtrates on sweet basil leaves was consistently correlated with the presence of the 24-kDa protein. Production of the 24-kDa protein was limited in cultures containing pectin or cellulose as the primary carbon source, or in cultures lacking sucrose or casamino acids. Water-soluble extracts from coca stems inhibited production of the 24-kDa protein, whereas cellulose and pectin did not. Components produced by the plant may limit production of the 24-kDa protein in infected plant tissue and thereby limit the response of the plant to the fungus. These results suggest the 24-kDa protein does not function in the symptomatic phase of the F. oxysporum f.sp. erythroxylicoca disease interaction.

Culture Media↗

The lesbian and gay liberation movement in the Presbyterian Church (U.S.A.), 1974-1996.

Since its founding in 1974, Presbyterians for Lesbian & Gay Concerns (PLGC) has led the movement toward full participation and membership for lesbian and gay people in the Presbyterian Church (U.S.A.). This is a story of that movement, told by a participant. It traces the development of current antigay policies in the church in 1976-78 in response to the first openly gay candidate for the ministry, PLGC's efforts to overturn these policies at annual General Assemblies, the growth of the pro-gay More Light Churches movement among Presbyterian congregations, the increasing number of antigay ecclesiastical court cases, study and dialogue on lesbian and gay issues across the denomination, and controversies over same-gender marriage, all culminating in the 1996 General Assembly, which endorsed civil rights for lesbian and gay couples, but also voted to send the controversial issue of lesbian and gay ordination to the 171 regional presbyteries of the church for an up or down vote. The battle for lesbian and gay equity in the church may well continue decades longer. Equity for gays and lesbians in society will not be fully won until the religious establishment learns how to apply its most basic principles of love, nurture, inclusive welcome, and support to lesbian and gay people.

Christianity↗

The Plasmodium falciparum 6 kb element is polycistronically transcribed.

The Plasmodium falciparum 6 kb element encodes three protein coding genes and highly fragmented large and small subunit rRNAs; its gene content makes it the probable mitochondrial genome. Many of the genes are encoded so close to each other that there is insufficient room for specific promoters upstream of each gene. RNase protection analysis of two rRNA fragments whose genes are adjacent provided evidence for a polycistronic transcript containing sequences from both, as well as separate small RNAs. To evaluate the possibility of further polycistronic transcription, several sets of oligonucleotide primers located in different regions of the 6 kb element were employed to amplify cDNAs. These analyses have revealed the existence of 6 kb element transcripts as long as 5.9 kb. Both mRNA and rRNA sequences are included on these putative precursor transcripts. Since these types of RNA are known to have different patterns of abundance changes during the erythrocytic portion of the parasite life cycle, RNA stability is presumably an important feature in regulating mitochondrial transcript abundance.

Animals↗

Autoantibodies in patients with silicone implants.

We assessed the prevalence of autoantibodies in women with silicone implants and controls. Five hundred consecutive patients with silicone implants, 25 age-matched normal women, 25 women with silicone implants and no rheumatic symptoms, and 100 women with fibromyalgia were tested. Immunofluorescence antinuclear antibodies (ANA) were performed using HEp-2 cells. Subtype autoantibodies were performed by enzyme-linked immunoassay and Western blot. ANA tests were positive in 30% of patients with silicone implants and rheumatic symptoms, 8% of age-matched normal women, 28% of women with silicone implants without clinical symptoms, and 25% of women with fibromyalgia and no silicone implants. The predominant ANA pattern was speckled (55%). ANA subtype testing was positive in 4.8% of patients and none of the controls. We conclude that a larger proportion of women with silicone implants have autoantibodies compared to age-matched asymptomatic women suggesting immune activation in women with silicone implants.

Adult↗

Cell cycle arrest and induction of apoptosis in pancreatic cancer cells exposed to eicosapentaenoic acid in vitro.

Eicosapentaenoic acid (EPA) has been shown to have an inhibitory effect on the growth of several pancreatic cancer cell lines in vitro. This study investigates the mechanism of growth inhibition and cytotoxicity of EPA on the pancreatic cancer cell line MIA PaCa-2. Cells were analysed for cell count, viability, cell cycle distribution and ultrastructural changes. There was a time- and dose-dependent decrease in cell count and viability in cultures of pancreatic cancer cells supplemented with EPA. Flow cytometric DNA analysis of MIA PaCa-2 cells incubated with EPA demonstrated the presence of sub G1 populations corresponding to the presence of apoptotic cells and the blockade of cell cycle progression in S-phase and G2/M-phase. The presence of apoptosis in EPA-supplemented cultures was further confirmed by DNA fragmentation and ultrastructural changes associated with apoptosis. Therefore, we conclude that EPA mediates its effect on the pancreatic cancer cell line MIA PaCa-2, at least in part, via cell cycle arrest and the induction of apoptosis.

Antineoplastic Agents↗

Stenotrophomonas maltophilia: emergence of multidrug-resistant strains during therapy and in an in vitro pharmacodynamic chamber model.

Emergence of Stenotrophomonas maltophilia as a nosocomial pathogen is becoming increasingly apparent. Pleiotropic resistance characterizes S. maltophilia. Furthermore, a slow growth rate and an increased mutation rate generate discordance between in vitro susceptibility testing and clinical outcome. Despite original susceptibility, drug-resistant strains of S. maltophilia are often recovered from patients receiving beta-lactams, quinolones, or aminoglycosides. Given the disparity among various in vitro susceptibility methods, this study incorporated a unique pharmacodynamic model to more accurately characterize the bacterial time-kill curves and mutation rates of four clinical isolates of S. maltophilia following exposure to simulated multidose regimens of ceftazidime, ciprofloxacin, gentamicin, and ticarcillin-clavulanate. Time-kill data demonstrated regrowth of S. maltophilia with all four agents. With the exception of ticarcillin-clavulanate, viable bacterial counts at the end of 24 h exceeded the starting inoculum. Ciprofloxacin only reduced bacterial counts by less than 1.0 log prior to rapid bacterial regrowth. Resistant mutant strains, identical to their parent strain by pulsed-field gel electrophoresis, were observed following exposure to each class of antibiotic. Mutant strains also had distinct susceptibility patterns. These data are consistent with previous reports which suggest that S. maltophilia, despite susceptibility data that imply that the organism is sensitive, develops multiple forms of resistance quickly and against several classes of antimicrobial agents. Standard in vitro susceptibility methods are not completely reliable for detecting resistant S. maltophilia strains; and therefore, interpretation of these results should be done with caution. In vivo studies are needed to determine optimal therapy against S. maltophilia infections.

Anti-Bacterial Agents↗

Sternothyrohyoideus myectomy or staphylectomy for treatment of intermittent dorsal displacement of the soft palate in racehorses: 209 cases (1986-1991).

The efficacy of sternothyrohyoideus myectomy (SM) and staphylectomy as treatments for intermittent dorsal displacement of the soft palate was evaluated in 209 racehorses (126 Thoroughbreds, 83 Standardbreds). The 2 most common complaints were respiratory tract noise (75% of horses) and exercise intolerance (51% of horses). Stopping, defined as the inability to finish the race at racing speed, was reported in 40% of the horses. Endoscopy at rest revealed evidence of abnormal epiglottic anatomy (hypoplasia or flaccidity) in 51% of the horses and abnormal soft palate function in 36% of the horses. Race records were available for 149 (77 Thoroughbreds, 72 Standardbreds) horses. The sex distribution consisted of 38% sexually intact males, 20% geldings, and 42% females, with a mean age of 3.4 years. Sixty-nine horses underwent staphylectomy, with a mean of 16 weeks to first stage after surgery. Eighty horses underwent SM, with a mean of 10 weeks to first start. Sternothyrohyoideus myectomy was performed on significantly more (P < 0.05). Thoroughbreds than Standardbreds, and staphylectomy was performed on significantly (P < 0.0001; chi 2 = 39.56) more Standardbreds than Thoroughbreds. After surgery, most horses (74%) had no change in class; however, more moved up in class (17%) than down (9%). On the basis of comparison of earnings for 3 starts before surgery with that for 3 starts after surgery, successful outcome was obtained in 60% of the horses (35 Thoroughbreds, 13 Standardbreds) that received SM and in 59% of the horses (11 Thoroughbreds, 30 Standardbreds) that received a staphylectomy.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Lamellar body secretion: ultrastructural analysis of an unexplored function of synoviocytes.

The intra- and extracellular distribution and relative density of lamellar bodies (LBs) were determined by electron microscopy in synovial biopsies from 20 non-rheumatoid arthritis (RA) patients. LBs were found on the synovial surface, in intimal cells, throughout intimal matrix, in blood vessel walls, in endothelial cytoplasm and within vascular lumena. Lamellar profiles were observed in type B synoviocytes within rough endoplasmic reticulum (RER), in association with the Golgi apparatus, and embedded in electron dense matrix (projection cores) in multivesicular bodies. Exocytotic release of mature LBs into intimal matrix was observed. In type A synoviocytes the outer lamellae of LBs were frequently found in contiguity with the limiting membrane of lysosomes. An in vitro investigation of the ultrastructural features of LB formation in cultured type B synoviocytes (from 3 non-RA patients) gave results similar to those obtained in biopsies. These studies provide ultrastructural evidence of synoviocyte activity in secreting and degrading phospholipid lubricant in a sophisticated system whose function and pathological derangements are largely unknown.

Humans↗

Studying the effect of clinical uncertainty on physicians' decision-making using ILIAD.

The influence of uncertainty on physicians' practice behavior is not well understood. In this research, ILIAD, a diagnostic expert system, has been used to study physicians' responses to uncertainty and how their responses affected clinical performance. The simulation mode of ILIAD was used to standardize the presentation and scoring of two cases to 46 residents in emergency medicine, internal medicine, family practice and transitional medicine at Methodist Hospital of Indiana. A questionnaire was used to collect additional data on how physicians respond to clinical uncertainty. A structural equation model was developed, estimated, and tested. The results indicate that stress that physicians experience in dealing with clinical uncertainty has a negative effect on their clinical performance. Moreover, the way that physicians respond to uncertainty has positive and negative effects on their performance. Open discussions with patients about clinical decisions and the use of practice guidelines improves performance. However, when the physician's clinical decisions are influenced by patient demands or their peers, their performance scores decline.

Clinical Competence↗

Appraisal of the stability of leukocytes in refrigerated urine.

There is limited evidence that urinary leukocytes are rapidly destroyed in alkaline hypotonic urine. We assessed the stability of leukocytes in urine specimens provided by 90 children with neurogenic bladder who attended a meningomyelocele clinic. No significant correlation was found between urine specific gravity and leukocyte survival after an interval of 4 h in a sample of 30 specimens from these patients. The survival of leukocytes was determined at 2 h and at 4 h in aliquots of these 30 specimens directly, and after adjustment to pH values of 5.0, 7.0, 8.0, 8.5, and 9.0. Statistically significant leukocyte destruction only occurred at pH 9.0 at 2 h (16%), at pH 8.5 at 4 h (19%), and at pH 9.0 at 4 h (57%). Only one of a further sample of 180 routine specimens had both a pH of > or = 8.5 and an interval to laboratory examination of > 2 h. No specimen had a specific gravity of < 1.002, and 93.9% had values of > or = 1.005. Urine pH and tonicity were not therefore important determinants of leukocyte stability in refrigerated samples examined within 4 h from this clinic population.

Cell Survival↗

Lamellar bodies in synoviocytes, mesothelium and specific epithelia as possible site of auto-antigen in rheumatoid disease.

Intracytoplasmic lamellar organelles identical in ultrastructure to surfactant-containing lamellar bodies found in type II pneumocytes, have been demonstrated in other tissues, in synoviocytes and mesothelial cells, in a distribution pattern which reflects the systemic expression of rheumatoid disease. Antibodies raised against surfactant protein A (SP-A), exhibit a ranking of tissue reactivity in area, intensity and density of cells which also parallels the frequency and degree of pathological involvement characteristic of rheumatoid disease, showing in ascending order of immunopositivity, lacrymal and salivary epithelia, pulmonary parenchyma, mesothelium and synoviocytes. Maximal tissue reactivity to anti-SP-A antibodies was found in the synovium of 55 rheumatoid patients exhibiting classical histopathological appearances of RA, in a pattern of immunostaining identical to that obtained with ML30, an antibody to mycobacterial heat shock protein 65kDa which, in turn, cross-reacted with SP-A in dot blot testing.

Arthritis, Rheumatoid↗

Induction of ethylene biosynthesis in Nicotiana tabacum by a Trichoderma viride xylanase is correlated to the accumulation of 1-aminocyclopropane-1-carboxylic acid (ACC) synthase and ACC oxidase transcripts.

Xylanase (EIX) from the fungus Trichoderma viride elicits ethylene biosynthesis in leaf tissues of Nicotiana tabacum cv Xanthi but not in cv Hicks. The increase in ethylene biosynthesis is accompanied by an accumulation of 1-aminocyclopropane-1-carboxylic acid (ACC), an increase in extractable ACC synthase activity, and increases in ACC synthase and ACC oxidase transcripts. Priming of increases in ACC synthase and ACC oxidase transcripts. Priming of leaves with ethylene (120 microL/L, 14 h) sensitizes the tissue, resulting in an enhanced response to EIX and increases in both the in vivo ACC oxidase activity and ACC oxidase transcript level. EIX and ethylene independently induce ACC oxidase. Inhibition of ethylene biosynthesis by aminoethoxyvinylglycine is not accompanied by a reduction in ACC oxidase transcript level, indicating that ethylene biosynthesis is not required. In contrast to the differential induction of ethylene biosynthesis by EIX in Xanthi versus Hicks cultivars, both cultivars respond to a chemical stress (induced by CuSO4) by enhancing ethylene production. This induction is accompanied by an increase in ACC synthase transcript but not in that of ACC oxidase.

Amino Acid Oxidoreductases↗

A short-term study of nitrofurantoin prophylaxis in children managed with clean intermittent catheterization.

OBJECTIVE: Because there is no evidence for the effectiveness of antibiotic prophylaxis in children with neurogenic bladder, the value of once-daily nitrofurantoin macrocrystals was assessed in a selected population with neurogenic bladder due to meningomyelocele. METHODS AND TRIAL POPULATION: Children with significant urinary tract abnormalities other than neurogenic bladder were excluded. A urinary tract "infection" was defined as > or = 10(8) colony forming units of bacteria/L of urine together with pyuria of > or = 50 x 10(6) leukocytes/L, and/or symptoms consistent with an urinary tract infection. Fifty-six children participated in a 24-week double-blinded, placebo-controlled cross-over study. The infection status was assessed at two weekly intervals or if relevant clinical manifestations occurred. RESULTS: For the whole trial the average percentage of "infections" per urine sample for each patient was reduced from 39% on placebo to 19% on single daily dose prophylaxis (P < .0003). For the first 12 weeks of the trial corresponding figures were 45% on placebo and 22% on prophylaxis (P < .0018). There was evidence for a marked carryover protective effect of nitrofurantoin into the placebo arm of the trial. CONCLUSION: Nitrofurantoin is an effective prophylactic agent during a 3-month period. Long-term studies are needed to confirm the reasonable expectation of a beneficial effect on urinary tract damage.

Child↗

Application of a leukocyte and nitrite urine test strip to the management of children with neurogenic bladder.

A urine leukocyte count of > or = 50/mm3 together with a bacterial count of > or = 10(5) colony-forming units (CFUs) per milliliter was used to define significant infection in 160 children with neurogenic bladder and evaluate the leukocyte and nitrite components of the Chemstrip 9 test. A Chemstrip 9 leukocyte reading of < or = 25 together with a negative nitrite reaction occurred in 99 children and had a sensitivity of 83.5% and a negative predictive value for infection of 97.0%. A Chemstrip 9 reading of > or = 500 leukocytes together with a positive nitrite reaction occurred in 18 children and had a sensitivity of 40% with a 100% positive predictive value for infection. Other combinations of Chemstrip 9 leukocyte and nitrite reactions were unhelpful or of uncertain value. Selection of up to three specimens from each patient increased the number of samples to 360 and provided general confirmation of the above conclusions. Nitrofurantoin may reduce the sensitivity of the nitrite strip reaction.

Child↗