A NodD-like protein activates transcription of genes involved with naringenin degradation in a flavonoid-dependent manner in Herbaspirillum seropedicae.

Herbaspirillum seropedicae is an associative, endophytic non-nodulating diazotrophic bacterium that colonises several grasses. An ORF encoding a LysR-type transcriptional regulator, very similar to NodD proteins of rhizobia, was identified in its genome. This nodD-like gene, named fdeR, is divergently transcribed from an operon encoding enzymes involved in flavonoid degradation (fde operon). Apigenin, chrysin, luteolin and naringenin strongly induce transcription of the fde operon, but not that of the fdeR, in an FdeR-dependent manner. The intergenic region between fdeR and fdeA contains several generic LysR consensus sequences (T-N11 -A) and we propose a binding site for FdeR, which is conserved in other bacteria. DNase I foot-printing revealed that the interaction with the FdeR binding site is modified by the four flavonoids that stimulate transcription of the fde operon. Moreover, FdeR binds naringenin and chrysin as shown by isothermal titration calorimetry. Interestingly, FdeR also binds in vitro to the nod-box from the nodABC operon of Rhizobium sp. NGR234 and is able to activate its transcription in vivo. These results show that FdeR exhibits two features of rhizobial NodD proteins: nod-box recognition and flavonoid-dependent transcription activation, but its role in H. seropedicae and related organisms seems to have evolved to control flavonoid metabolism.

Naringenin degradation by the endophytic diazotroph Herbaspirillum seropedicae SmR1.

Several bacteria are able to degrade flavonoids either to use them as carbon sources or as a detoxification mechanism. Degradation pathways have been proposed for several bacteria, but the genes responsible are not known. We identified in the genome of the endophyte Herbaspirillum seropedicae SmR1 an operon potentially associated with the degradation of aromatic compounds. We show that this operon is involved in naringenin degradation and that its expression is induced by naringenin and chrysin, two closely related flavonoids. Mutation of fdeA, the first gene of the operon, and fdeR, its transcriptional activator, abolished the ability of H. seropedicae to degrade naringenin.

Evidence for the endophytic colonization of Phaseolus vulgaris(common bean) roots by the diazotroph Herbaspirillum seropedicae

Herbaspirillum seropedicae is an endophytic diazotrophic bacterium, which associates with important agricultural plants. In the present study, we have investigated the attachment to and internal colonization of Phaseolus vulgaris roots by the H. seropedicae wild-type strain SMR1 and by a strain of H. seropedicae expressing a red fluorescent protein (DsRed) to track the bacterium in the plant tissues. Two-day-old P. vulgaris roots were incubated at 30°C for 15 min with 6 x 10(8) CFU/mL H. seropedicae SMR1 or RAM4. Three days after inoculation, 4 x 10(4) cells of endophytic H. seropedicae SMR1 were recovered per gram of fresh root, and 9 days after inoculation the number of endophytes increased to 4 x 10(6) CFU/g. The identity of the recovered bacteria was confirmed by amplification and sequencing of the 16SrRNA gene. Furthermore, confocal microscopy of P. vulgaris roots inoculated with H. seropedicae RAM4 showed that the bacterial cells were attached to the root surface 15 min after inoculation; fluorescent bacteria were visible in the internal tissues after 24 h and were found in the central cylinder after 72 h, showing that H. seropedicae RAM4 is capable of colonizing the roots of the dicotyledon P. vulgaris. Determination of dry weight of common bean inoculated with H. seropedicae SMR1 suggested that this bacterium has a negative effect on the growth of P. vulgaris.

Naringenin regulates expression of genes involved in cell wall synthesis in Herbaspirillum seropedicae.

Five thousand mutants of Herbaspirillum seropedicae SmR1 carrying random insertions of transposon pTnMod-OGmKmlacZ were screened for differential expression of LacZ in the presence of naringenin. Among the 16 mutants whose expression was regulated by naringenin were genes predicted to be involved in the synthesis of exopolysaccharides, lipopolysaccharides, and auxin. These loci are probably involved in establishing interactions with host plants.

Evidence for the endophytic colonization of Phaseolus vulgaris (common bean) roots by the diazotroph Herbaspirillum seropedicae.

Herbaspirillum seropedicae is an endophytic diazotrophic bacterium, which associates with important agricultural plants. In the present study, we have investigated the attachment to and internal colonization of Phaseolus vulgaris roots by the H. seropedicae wild-type strain SMR1 and by a strain of H. seropedicae expressing a red fluorescent protein (DsRed) to track the bacterium in the plant tissues. Two-day-old P. vulgaris roots were incubated at 30°C for 15 min with 6 x 10(8) CFU/mL H. seropedicae SMR1 or RAM4. Three days after inoculation, 4 x 10(4) cells of endophytic H. seropedicae SMR1 were recovered per gram of fresh root, and 9 days after inoculation the number of endophytes increased to 4 x 10(6) CFU/g. The identity of the recovered bacteria was confirmed by amplification and sequencing of the 16SrRNA gene. Furthermore, confocal microscopy of P. vulgaris roots inoculated with H. seropedicae RAM4 showed that the bacterial cells were attached to the root surface 15 min after inoculation; fluorescent bacteria were visible in the internal tissues after 24 h and were found in the central cylinder after 72 h, showing that H. seropedicae RAM4 is capable of colonizing the roots of the dicotyledon P. vulgaris. Determination of dry weight of common bean inoculated with H. seropedicae SMR1 suggested that this bacterium has a negative effect on the growth of P. vulgaris.

Inter-domain cross-talk controls the NifA protein activity of Herbaspirillum seropedicae.

Herbaspirillum seropedicae is an endophytic diazotroph, which colonizes sugar cane, wheat, rice and maize. The activity of NifA, a transcriptional activator of nif genes in H. seropedicae, is controlled by ammonium ions through a mechanism involving its N-terminal domain. Here we show that this domain interacts specifically in vitro with the N-truncated NifA protein, as revealed by protection against proteolysis, and this interaction caused an inhibitory effect on both the ATPase and DNA-binding activities of the N-truncated NifA protein. We suggest that the N-terminal domain inhibits NifA-dependent transcriptional activation by an inter-domain cross-talk between the catalytic domain of the NifA protein and its regulatory N-terminal domain in response to fixed nitrogen.

Recent developments in the structural organization and regulation of nitrogen fixation genes in Herbaspirillum seropedicae.

Herbaspirillum seropedicae is a nitrogen-fixing bacterium found in association with economically important gramineae. Regulation of nitrogen fixation involves the transcriptional activator NifA protein. The regulation of NifA protein and its truncated mutant proteins is described and compared with that of other nitrogen fixation bacteria. Nitrogen fixation control in H. seropedicae, of the beta-subgroup of Proteobacteria, has regulatory features in common with Klebsiella pneumoniae, of the gamma-subgroup, at the level of nifA expression and with rhizobia and Azospirillum brasilense, of the alpha-subgroup, at the level of control of NifA by oxygen.

Test of a nursing intervention to promote adjustment to fibromyalgia.

PURPOSE: This was a test to detect whether a 4-week cognitive behavioral nursing program was effective in increasing adjustment to fibromyalgia (FM) and if the treatment effect would last over time. DESIGN: This was a control and treatment group experimental longitudinal study with outcome measures obtained at pretest and every 3 months for 1 year. SAMPLE: A sample of 71 subjects continued their participation throughout the first year of the study. FINDINGS: Treatment subjects had improved posttreatment adjustment and symptom severity compared to control subjects. When subjects with high pretest psychosocial distress (n = 5) were removed from the analysis, these findings were statistically significant. IMPLICATIONS FOR NURSING PRACTICE: The article can provide direction for developing new comprehensive nursing intervention for patients seen with orthopaedic problems. The intervention schedule may help nurses expand their use of interventions for FM patients. Orthopaedic nurses are especially suited for this challenge.

Two roles for integration host factor at an enhancer-dependent nifA promoter.

Control of transcription in prokaryotes often involves direct contact of regulatory proteins with RNA polymerase. For the sigma54 RNA polymerase, regulatory proteins bound to distally located enhancers engage the polymerase via DNA looping. The sigma54-dependent nifA promoter of Herbaspirillum seropedicae (Hs) is activated under nitrogen-limiting growth conditions. Potential enhancers for the nitrogen control activators NTRC and NIFA and binding sites for integration host factor (IHF) and sigma54-holoenzyme were identified. DNA footprinting experiments showed that these sites functioned for protein binding. Their involvement in the promoter regulation was explored. In vitro, activation of the Hs nifA promoter by NTRC is stimulated by the DNA bending protein IHF. In marked contrast, activation by NIFA is greatly reduced by IHF, thus diminishing potentially destabilizing autoactivation of the nifA promoter by NIFA. Additionally, high levels of NIFA appear to limit NTRC-dependent activation. This inhibition is IHF dependent. Therefore, IHF acts positively and negatively at the nifA promoter to restrict transcription activation to NTRC and one signal transduction pathway.

National survey of nursing program options designed for the second degree student.

There is a current trend for schools of nursing to begin second degree options. Given the current economic situation, this is a win/win situation that benefits the second degree student, schools of nursing, the profession, and the community in general.

Self-efficacy as a predictor of adjustment to multiple sclerosis.

The ability of self-efficacy (SE) and outcome expectations (OE) to predict adjustment to multiple sclerosis (MS) was explored. A sample of 62 respondents who had MS was used to test study hypotheses. Self-efficacy expectations predicted 24% of the variance in adjustment to chronic physical illness. Outcome expectations did not significantly add to the predictive power of SE. However, the model containing SE, OE and degree of disability predicted 51% of the variance in adjustment.

A survey of nursing students' knowledge of cancer pain control.

The World Health Organization estimates that approximately 3.5 million people suffer daily from cancer pain. Recently, a Midwestern state was named by the World Health Organization to lead worldwide efforts in controlling the pain experienced by cancer patients. As part of this effort, the Nursing Education Committee conducted a statewide study of first year and final year nursing students from 19 nursing programs. The purpose of this study was to determine nursing students' perceptions and knowledge about cancer pain control. After the deans and directors of the nursing programs were contacted to obtain their agreement to participate, questionnaires composed of 26 items were mailed to each nursing school and distributed to students. Nine hundred thirty-eight questionnaires were returned to the researchers, realizing a 40% return rate. Data analysis reflects poor knowledge about the prevalence of cancer pain and its management. Using the student's t-test, significant differences between the scores of first year and last year students were found with last year students achieving higher mean scores. It was concluded that more information about how to manage cancer pain needs to be provided in nursing curricula. It is recommended that faculty members frequently update their knowledge and skills about cancer pain management.

A test of the relationship between health locus of control and the course of multiple sclerosis.

This study explored the relationship between health locus of control and the trajectory of multiple sclerosis. A random sample of 100 respondents with multiple sclerosis was selected from the membership list of a state multiple sclerosis support group. The subjects were interviewed in their homes and completed study instruments. Respondents with an internal health locus of control orientation had more knowledge of their disease, practiced more self-care, and had a more benign course of multiple sclerosis than those with an external locus of control. Additional findings included an overall lower divorce rate for the respondents as well as a poor employment outlook.

Nursing and marketing: collaborative teaching.

The authors discuss a graduate course in health care marketing using both nursing and marketing professionals in a collaborative teaching effort. Didactic material was supplemented with practical experience in designing promotional and marketing strategies.

Cancer pain control: one state's experience.

The World Health Organization estimates that approximately 3.5 million people suffer daily from cancer pain. Approximately 30% to 40% of people with intermediate stages of cancer and 55% to 90% of patients with advanced or terminal disease have pain. A multidisciplinary effort is under way in Wisconsin to improve cancer pain management. In recognition of the state's initiative, the World Health Organization has designated Wisconsin a demonstration state for cancer pain management. Support for staffing is provided by the United States Public Health Service Interagency Committee on Pain and Analgesia. In December 1986, 65 people representing 50 health organizations met to develop a comprehensive plan of action to improve pain management in people with cancer. In this article the various statewide activities focused at improving cancer pain management are discussed.