The phytochrome response of the Lemna gibba NPR1 gene is mediated primarily through changes in abscisic acid levels

Two important signaling systems involved in the growth and development of plants, those triggered by the photoreceptor phytochrome and the hormone abscisic acid (ABA), are involved in the regulation of expression of the NPR1 gene of Lemna gibba. We previously demonstrated that phytochrome action mediates changes in ABA levels in L. gibba, correlating with changes in gene expression evoked by stimulation of the phytochrome system. We have now further characterized phytochrome- and ABA-mediated regulation of L. gibba NPR1 gene expression using a transient particle bombardment assay, demonstrating that regulatory elements controlling responses to both stimuli reside within 156 nucleotides upstream of the transcription start. Linker scan (LS) analysis of the region from -156 to -70 was used to identify two specific requisite and nonredundant cis-acting promoter elements between -143 to -135 (LS2) and -113 to -101 (LS5). Mutation of either of these elements resulted in a coordinate loss of regulation by phytochrome and ABA. This suggests that, unlike the L. gibba Lhcb2*1 promoter, in which phytochrome and ABA regulatory elements are separable, the phytochrome response of the L. gibba NPR1 gene can be attributed to alterations in ABA levels.

Thioredoxin peroxidase from Onchocerca volvulus: a major hydrogen peroxide detoxifying enzyme in filarial parasites

Random screening of an Onchocerca volvulus third-stage (L3) cDNA library identified a highly abundant cDNA encoding a newly discovered antioxidant enzyme, thioredoxin peroxidase (TPx), a member of the peroxidoxin superfamily. This TPx cDNA (Ov-tpx-2) encodes a polypeptide of 199 amino acid residues with a calculated molecular weight of 21,890 Da. The Ov-tpx-2 cDNA represents roughly 2.5% of the total cDNAs from the L3 cDNA library. The gene was expressed in Escherichia coli and the protein product was shown to have antioxidant activity. Antiserum raised against Ov-TPX-2 recognized a native protein from extracts of both the L3 and adult-stages with a molecular weight of 22 kD. The localization and stage-specificity of Ov-TPX-2 protein was analyzed by immunocytochemistry and immunoelectron microscopy using monospecific antibodies. Expression was detected in late first-stage larvae during development in the vector and increased in intensity during differentiation to the infective L3-stage. The antigen was also detected in post-infective larvae and adult worms. In larvae, Ov-TPX-2 protein was predominantly localized to the hypodermis and cuticle, with additional sites in the hypodermal chords and multivesicular bodies. In adult worms, the primary sites of expression were the uterine epithelium and intestine, with additional labeling of the body wall and cuticle. Developing embryos and microfilariae in utero were bathed in Ov-TPX-2 protein discharged from epithelial cells. These results suggest that Ov-TPX-2 may protect the parasites from being damaged by host-generated oxidative stress and that Ov-TPX-2 protein provides the H2O2-detoxifying activity predicted but not previously identified in filarial parasites. Its highly upregulated expression in infective larvae may aid in parasite establishment following transmission to the definitive host.

Impairment of the sarcolemmal phospholipase D-phosphatidate phosphohydrolase pathway in diabetic cardiomyopathy

Experimental evidence suggests that the myocardial phospholipase D (PLD)-phosphatidate phosphohydrolase (PAP) signalling pathway may regulate Ca2+ movements and contractile performance of the heart. As abnormal Ca2+ homeostasis is associated with diabetic cardiomyopathy, we examined the functional status of the PLD/PAP pathway in sarcolemmal (SL) membranes isolated from insulin-dependent diabetic rat hearts at 8 weeks after a single i.v. injection of streptozotocin (65 mh/kg b.w.). Compared to age-matched controls, SL PLD hydrolytic (producing phosphatidic acid, PtdOH) and transphosphatidylation activities were significantly depressed in diabetic animals, while SL PAP was significantly augmented. The net effect of the altered enzyme activities in diabetic animals was a severely diminished (by 67% of controls) membrane level of PLD-derived PtdOH. Two weeks of insulin therapy to the 6 week diabetic animals normalized PLD, while PAP activity and PtdOH level were significantly modified, but had not completely reverted to control values. The observed changes were not due to hypothyroidism associated to the diabetic model as the induction of hypothyroidism in healthy non-diabetic animals did not affect SL PLD and PAP. The results suggest that the severe reduction of PLD-derived PtdOH and increased production of sn-1,2-diacylglycerol by phosphatidate phosphohydrolase may lead to an impairment of the bioprocesses mediated by these signalling lipids.

Subcellular alterations in cardiac phospholipase D activity in chronic diabetes

Several studies have suggested that myocardial phospholipase D (PLD) and its hydrolytic product, phosphatidic acid (PtdOH), may regulate Ca2+ movements and contractile performance of the heart. Since abnormal intracellular Ca2+ handling is a major factor of myocardial dysfunction in chronic diabetes, we examined subcellular changes in PLD activity in myocardium from insulin-dependent diabetic rats. Diabetes in rats was induced by a single i.v. injection of streptozotocin (65 mg/kg body wt) and 8 weeks later the ventricular tissue was processed for the isolation of sarcolemma, sarcoplasmic reticulum and mitochondria. Compared to age-matched controls, the sarcolemmal, sarcoplasmic reticular and mitochondrial PLD activities were significantly depressed in the diabetic animals. The depressed sarcolemmal PLD activity was normalized, whereas the sarcoplasmic reticular and mitochondrial enzyme activities were partially reversed upon treating the 6-week diabetic rats with insulin for a period of 2 weeks. These data suggest that the reduction of PLD-derived PtdOH may lead to an impairment in this phospholipid signal transduction pathway and subsequent cardiac dysfunction in chronic diabetes.

The relationship of patients' perceptions of holistic nurse caring to satisfaction with nursing care

Hospitalized patients interact with nurses more often than with other health care providers. Qualitative studies have identified patients' and nurses' perceptions of nurse caring behaviors. Few studies have explored nurse caring behavior in relation to patient satisfaction. The article describes a study designed to determine whether there is a relationship between patients' perceptions of nurse caring and satisfaction with nursing care and whether selected patient variables significantly affect that relationship. In the patient population studied, after controlling for patient variables of age, gender, and level of pain, a significant positive relationship was found between patients' perceptions of nurse caring and their satisfaction with nursing care.

Using an outside consultant for staff development

In this article the author describes the use of a nurse educator/clinical nurse specialist as an outside consultant to provide a program to educate staff nurses about oncology patient care. The continuing education program included a didactic and clinical practicum. The program provided nurses with specialized knowledge about an expanding patient population, improved the level of oncology patient care, and increased the confidence of the physicians and community members in the level of oncology nursing care.

Caring in patient-focused care: the relationship of patients' perceptions of holistic nurse caring to their levels of anxiety

Holistic nurse caring, also called patient-focused care, is a helping relationship between nurse and patient with the potential to enhance health and healing. Few studies, however, have examined the relationship of the process of nurse caring to patient outcomes. Hospitalized patients face many stressors that cause anxiety. It is known that abnormally high levels of anxiety can interfere with patients' recovery. The article reports a study of patients' perceptions of holistic nurse caring and the relationship of perceptions of caring to levels of anxiety. Patients perceived caring to be evident, and there was a significant relationship between these perceptions and patients' levels of anxiety.

A polymerase chain reaction-based assay for detection of Wuchereria bancrofti in human blood and Culex pipiens

Human blood samples and indoor-resting Culex pipiens were collected in 33 randomly selected houses from different sectors of a village in the Nile Delta of Egypt which was endemic for Wuchereria bancrofti. Blood was also collected from subjects with no history of living in filarial endemic areas. Human blood samples were divided and assessed by both membrane filtration and polymerase chain reaction (PCR). Similarly, mosquito samples were assessed by both dissection and PCR. Blood pools representing each household were tested by PCR. If a pool gave a positive result, then individual blood specimens were also tested by PCR. Of the 33 houses tested, both membrane filtration and blood pools assayed by PCR identified 14 (42.4%) 'infected houses'. PCR detected parasite deoxyribonucleic acid (DNA) in blood pools from an additional 3 households that gave negative results by membrane filtration. Of 178 endemic blood samples tested by membrane filtration, 22 (12.3%) had microfilariae and all were individually positive by PCR. Although microfilaria counts were lower in blood collected during the day than in night-collected blood, the PCR results were consistent, regardless of time of collection. All non-endemic blood samples were negative by PCR. Among the 33 houses rested, mosquito pools assayed by PCR identified 17 (51.5%) as 'infected households'. Of these, 8 houses (47%) contained at least one microfilaraemic resident. One 'infected household' was identified by mosquito dissection. We concluded that PCR is a powerful epidemiological tool for screening villages for the prevalence of W. bancrofti. PCR detection of W. bancrofti DNA in blood-fed mosquitoes could be used initially to locate endemic areas with transmission of bancroftian filariasis. PCR detection of W. bancrofti DNA in blood collected during the day could then be used to assess W. bancrofti infection rates.

The relationship between deprivation, ethnicity and dental health in 5-year-old children in Leeds, UK

OBJECTIVE

To investigate the relationship between material deprivation, ethnicity, dental health and related behaviour in the five-year-old population of Leeds.

DESIGN

Analytical survey using a stratified cluster sample of primary schools and a questionnaire to parents. Children were assigned to one of five bands according to the ranking of the Townsend deprivation index for the census enumeration district in which they lived. Standard clinical criteria were used.

SETTING

Clinical examinations were carried out in school by four trained and calibrated examiners.

PARTICIPANTS

Two thousand six hundred and seventy seven children were examined and 1881 parental questionnaires were returned (70 per cent response).

OUTCOME MEASURES

Caries experience expressed as mean dmft.

RESULTS

Caries experience increased significantly with deprivation. Deprivation gradients were found in reported dental visiting, parental dental attendance and use of the Community Dental Service. Differences in caries experience between ethnic groups were independent of deprivation score with Asian children from the most deprived districts having a higher mean dmft than their white Caucasian and Afro-Caribbean counterparts (4.80, 3.21, 2.00; P < 0.001). Muslim Asians had significantly higher (P < 0.001) caries experience (dmft = 4.63) than non-Muslim Asians (dmft = 2.08) and the difference was maintained when the effect of deprivation was controlled (P < 0.05).

CONCLUSIONS

The Townsend index is a useful indicator of dental health and related behaviour among populations but does not explain variations between ethnic groups.

Characterization of the 5' flanking region of the human complement factor H gene

The promoter region of the human factor H gene was cloned and a 3 kb Eco RI fragment was sequenced. Primer extension and S1 nuclease analysis were used to determine the transcription start site, which was found to be 10-11 nucleotides upstream of the published cDNA sequence. No canonical TATA or CCAAT boxes were found in conjunction with this site. The sequence from the human H promoter region was compared to that from the mouse gene. There was a region of 800 bp that was 62.5% identical between the two sequences. The sequences of the two promoter regions were compared to a database of transcription factor binding sites. Five elements were identified that matched the consensus sequence 100% and were identical in the two promoter sequences. Promoter assays using the luciferase reporter gene demonstrated that this region contained a functional transcription start site and putative enhancer elements. U118-MG astroglioma cells and Hep3b hepatoma cells were incubated with various cytokines to measure effects on their factor H mRNA levels. Interferon-gamma (IFN-gamma), but not interleukin-1 (IL-1), tumour necrosis factor alpha (TNF-alpha) or IL-6, was able to increase the level of H mRNA in both cell lines.

Effects of phosphodiester and phosphorothioate antisense oligodeoxynucleotides on cell lines which overexpress c-myc: implications for the treatment of Burkitt's lymphoma

The product of the c-myc proto-oncogene is a highly conserved nuclear phosphoprotein whose expression is closely linked to cellular proliferation and differentiation. We have been interested in developing an antisense oligodeoxynucleotide (ODN) strategy to inhibit the proliferation of c-myc-dependent malignancies for use in future specific therapies and bone marrow purging regimens. Our experimental approach was to incubate either antisense or sense ODNs, spanning the 5' cap region of the c-myc gene, with c-myc overexpressing cell lines (HL-60) Raji, MJBL, CA-46) for up to seven days. Proliferation assay to test the inhibitory effect of an unmodified antisense ODN 15-mer (GCACAGCTCGGGGGT) showed that concentrations as low as 50 micrograms/ml significantly decreased proliferation of HL-60 cells by approximately 40% (P < 0.0001; n = 6) compared to controls. Clonogenic assays showed that the same antisense ODN inhibited colony formation by MJBL (40%0 and Raji (52%) cells. Subsequent experiments to study the effect of a more nuclease-stable, phosphorothioate-modified antisense ODN 18-mer (GCAGCACAGCTCGGGGGT) revealed 66% inhibition of HL-60 cell proliferation at 96 and 120 hours at 50 micrograms/ml, whereas sense ODN control had no effect. However, tenfold less of the modified antisense ODN (1 micrograms/ml) was required to inhibit proliferation of HL-60 cells by 50% compared to the unmodified antisense ODN. A decrease in the HL-60 native c-myc protein level was also observed with 100 micrograms/ml of modified antisense ODN, but not with the sense ODN control, by immunoblot analysis. Additionally, concentrations up to 10 micrograms/ml of either modified antisense or sense ODN did not decrease CFU-GM formation (145 +/- 35%, P = 0.27) in human bone marrow, suggesting that these levels of ODN would have a negligible effect on normal hematopoietic cells. These pilot data suggest that modified antisense ODN directed at the cap region of the c-myc gene could specifically inhibit c-myc expression at a single, lower dose than unmodified ODN and may play a future role in inhibiting the growth of c-myc-dependent malignant cells.

The dental management of children with sickle cell disease and beta-thalassaemia: a review

This paper reviews two groups of haemoglobinopathies: sickle cell disorders and beta-thalassaemias. The medical aspects and dental management of children with these conditions are discussed. These conditions are rare in the white indigenous population of the UK but affect a sizeable proportion of the minority ethnic community. Dentists need to be aware of the medical implications for patients who have these disorders and should co-ordinate their dental care accordingly.

Cationic lipids reduce time and dose of c-myc antisense oligodeoxynucleotides required to specifically inhibit Burkitt's lymphoma cell growth

Burkitt's lymphoma is characterized by a translocation of the c-myc gene with one of the immunoglobulin loci which activates overexpression of the c-myc oncogene. Antisense-oligodeoxynucleotides (AS-ODNs) offer the potential to block specific c-myc gene expression within lymphoma cells, but often exhibit a low efficiency of AS-ODN uptake. In this study, a polycationic lipid reagent, Lipofectamine (LFM), was utilized as a vehicle to increase efficiency of delivery, decrease the time needed to observe an inhibitory effect, and decrease the AS-ODN dose. The objective was to develop a more efficient and rapid in vitro AS-ODN strategy to inhibit proliferation of c-myc-dependent lymphoma cells and to test the specificity of Burkitt's lymphoma cell line-directed AS-ODNs for potential use as molecular purging agents in bone marrow transplantation. Proliferation assays were performed to determine the inhibitory effect of the AS-ODNs on two Burkitt's lymphoma cell lines with different chromosomal translocations, Daudi and ST486, in medium containing 8.5 microM LFM. AS-ODNs at a concentration of 0.36 microM induced a significant decrease in proliferation for both cell lines using the specific AS-ODN for each respective translocation. Within 5 h, Daudi responded to its specific AS-ODN/lipid complexes with a 35% decrease in proliferation, compared to cells which received no treatment or Daudi-specific AS-ODN without LFM (P = 0.0001). Daudi showed an insignificant decrease in proliferation when treated with an AS-ODN specific for the ST486 translocation (4%, P = 0.26). ST486 proliferation was decreased by 52% when treated with the specific antisense for ST486 compared to no treatment or ST486-specific AS-ODN without LFM (P < 0.003). Treatment with the AS-ODN specific for Daudi showed an insignificant 4% decrease (P = 0.42). Controls, including sense ODN for structure, reverse AS-ODN for structure and base composition, and AS-ODN without LFM, did not produce a significant change in cells treated with LFM alone or cells receiving no treatment. Clonogenic assays of both Daudi and ST486 treated with their specific AS-ODNs revealed a 50% inhibition of colony formation after the 5 h incubation as compared to no treatment. Confocal laser scanning microscopy verified that cellular uptake of AS-ODN was enhanced by cationic lipids. Immunoblot analysis showed a 63 +/- 5% and a 50 +/- 3% reduction in intracellular c-myc levels for Daudi and ST486, respectively, when their respective AS-ODNs were administered. Normal bone marrow progenitors were unaffected by the ODN/LFM complexes. These results suggest that the specific c-myc AS-ODN/LFM complexes inhibit c-myc-dependent tumor proliferation at an earlier time and at a lower dose compared to no lipid facilitation. This approach may form the basis for utilizing specific AS-ODN/LFM therapy either alone or in a cocktail of other agents as an ex vivo molecular purging approach to autologous stem cell transplantation in Burkitt's lymphoma.

Positron emission tomographic analysis of central 5-hydroxytryptamine2 receptor occupancy in healthy volunteers treated with the novel antipsychotic agent, ziprasidone

Ziprasidone is a novel antipsychotic agent, with high affinity for dopamine D2 and serotonin (5-HT2) receptors in vitro and in animal models. The goal of this study was to determine the time course of 5-HT2 receptor occupancy (%RO) in healthy humans after a single p.o. dose. Positron emission tomography with the 5-HT2 ligand, [18F]setoperone, was performed in eight male volunteers, in the drug-naive, base-line (BL) state and 4 to 18 hr after ziprasidone (40 mg). Cerebral cortical binding potential [BP, maximum number of available receptors/KD or association rate for specific binding (k3)/dissociation rate for specific binding (k4)] was estimated using the cerebellum as reference. Transport rate from plasma to brain (K1), transport rate from brain to plasma (k2), association rate of nonspecific binding (k5) and dissociation rate of nonspecific binding (k6) were derived by fitting cerebellar time-activity curves to a three-compartment model. Fitting of cortical data to a 4-compartment model with K1/k2, k5 and k6, fixed at cerebellar values, was used to determine k3 and k4. %RO was calculated using the relation: %RO = [(BPBL-BPDRUG)/BPBL] x 100%. At BL, cortical parameter (mean +/- S.E.M) were: K1 = 0.121 +/- 0.0072 ml.min-1.g-1; k2 = 0.0581 +/- 0.004 min-1; k3 = 0.321 +/- 0.0026 min-1; k4 = 0.0957 +/- 0.0059 min-1; k5 = 0.0147 +/- 0.00066 min-1; and k6 = 0.0059 +/- 0.00042 min-1. Ziprasidone did not effect K1, k2, k5 or k6; however, k3 was reduced and k4 was elevated (P < .01). RO was nearly complete at 4 hr after dosing (98%) and remained elevated at 18 hr (46%). Plasma concentrations were well described by a biexponential function and decreased much more rapidly than RO. These results establish that ziprasidone has high potency for blocking 5-HT2 receptors in healthy humans; a potentially important characteristic of atypical antipsychotic agents.

The diagnostic reliability of clinical dental auxiliaries in caries prevalence surveys--a pilot study

The Nuffield Report recommended the development of further education and training for dental auxiliary personnel. The extent to which clinical dental auxiliaries might carry out oral assessments is under consideration currently. While other countries have employed clinical dental auxiliaries as examiners in national surveys, there is no evidence to suggest that they are able to perform oral assessments effectively in the United Kingdom. This study aimed to investigate the possibility of using dental hygienists or therapists as examiners in epidemiological surveys. Five dentists and three clinical dental auxiliaries were trained and calibrated together using standardised BASCD training procedures. Forty 5-year-old children in Leeds were recruited to the training and calibration exercise. Data were analysed according to BASCD recommendations. There were no differences in performance between dentists and auxiliaries. All examiners fell within 95 percent confidence limits of the group mean dt, mt, ft and dmft. Mean grouped dmft scores for the benchmark examiner, dentists and auxiliaries were 1.92, 1.84 and 1.92 respectively. Sensitivity values for dentists and auxiliaries ranged from 0.54 to 1.00 and 0.80 to 0.94 respectively. Kappa scores were 0.70 to 0.90 for dentists; and 0.82 to 0.87 for the auxiliaries. It was concluded that the dental hygienists and therapist recruited to this study could be used in epidemiological surveys of caries in 5-year-old children.

Caries experience, tooth loss and oral health-related behaviours among Bangladeshi women resident in West Yorkshire, UK

Several studies have reported high levels of caries experience among young Muslim Asian children, but there has been little corresponding information on adult dental health or related health behaviours. This paper presents the results of a questionnaire together with clinical oral findings among first generation Bangladeshi women aged over 25 years. The majority chewed betel quid with tobacco, were of rural origin, used traditional oral hygiene practices and had never visited a dentist. Of the 247 examined, only one was edentulous. A very low level of caries experience was recorded, a mean DFT score of 1.87 at 25-34 years of age, with an average of 1.05 missing teeth. Coronal caries experience was found to be independent of oral hygiene methods, including the use of fluoride toothpaste, or the frequency of betel quid chewing. It was concluded that Bangladeshi adult women have considerably lower levels of caries experience and tooth loss than United Kingdom adults as represented in recent national surveys.

A polymerase chain reaction assay for the detection of Wuchereria bancrofti in blood samples from French Polynesia

A polymerase chain reaction (PCR) assay based on a highly repeated deoxyribonucleic acid (DNA) sequence found in Wuchereria bancrofti (the SspI repeat) has been developed to address the shortcomings of traditional diagnostic methods. In this field study in a W. bancrofti endemic region of French Polynesia, 373 human blood samples were collected and 100 microL of blood were screened by the SspI PCR assay and 1 microL by membrane filtration. The SspI PCR assay detected 99 of 113 blood samples in which microfilariae had been detected by filtration (sensitivity of 88%) with a specificity of 100%. All the samples missed by the SspI PCR assay had less than 8 microfilariae per mL of blood. To evaluate the efficacy of screening larger blood samples by PCR, both 100 microL and 500 microL samples from 50 patients with very low-level microfilaraemia were screened by the SspI PCR assay; the sensitivity increased from 60% to 84% when using the larger volume of blood. Finally, an enzyme-linked immunosorbent assay-based version of the SspI PCR assay was used to screen blood from 12 patients following treatment with diethylcarbamazine, ivermectin, or both. These results showed that the PCR assay closely paralleled the presence or absence of microfilariae in the blood and that no increase in the DNA level was seen immediately following drug treatment.

Evaluation of a polymerase chain reaction-based assay for diagnosis of Wuchereria bancrofti infection

To assess the utility of a polymerase chain reaction (PCR)-based method for diagnosis of Wuchereria bancrofti infection, blood, plasma, and paraffin-embedded tissue samples were tested using a PCR-based assay that detects a W. bancrofti-specific repetitive DNA sequence. The assay was positive in 100 microL of blood from 40 of 42 microfilaria-positive subjects, the 2 subjects with negative assays having microfilarial counts of 1. Samples from 127 uninfected subjects were PCR-negative. The assay was also positive in 7 of 10 daytime samples in regions where infection is nocturnally periodic; PCR amplification from paraffin-embedded sections established the diagnosis of W. bancrofti infection in another 2 cases. A microtiter ELISA plate-based method was developed for rapid evaluation of large numbers of samples. These results suggest that this PCR-based assay will be useful in diagnosis of W. bancrofti infection in a variety of clinical settings.

Brain-derived neurotrophic factor and peripheral nerve regeneration: a functional evaluation

The potential benefit of brain-derived neurotrophic factor (BDNF) on motor-nerve regeneration after transection injury in 24 adult rats was evaluated after entubulation repair. Gait analysis for ankle angle and tension transduction device (TTD) strain-gauge measurements yielded functional evaluation of regeneration. The BDNF (15 mg/mL) or phosphate buffered saline (control) was injected into the silicone elastomer (Silastic) channel. Gait analysis performed 0, 2, 4, 6, 10, and 12 weeks after injury demonstrated a significant difference between uninjured and injured legs of 23 and 43 degrees, respectively (P<.001, analysis of variance). The TTD evaluation 13 weeks after injury demonstrated a significant decrease in force development of injured compared to uninjured legs, 148 and 58 g, respectively (P<.001). No functional benefits were demonstrated between BDNF-treated versus control-treated animals in either model for a single exposure to BDNF.

Innovative strategies for promoting clinical scholarship: a holistic approach

The article discusses a holistic approach to clinical scholarship by examining dimensions of scholarship and patterns of knowing. Innovative clinical teaching strategies in relation to these dimensions of scholarship and patterns of knowing are identified. Experiential learning, content mapping, and portable patient problem packs are explored. Knowledge building and creativity in the process of educating students are imperative. Nurse educators are challenged to develop new paradigms for nursing education that create a dynamic learning environment and result in enhanced clinical scholarship.