The in vitro and in vivo pharmacology of antisense oligonucleotides targeted to murine Stat6

OBJECTIVE AND DESIGN

This study was designed to establish whether phosphorothioate (PS) antisense oligonucleotides (AS-ODN) targeted to Stat6 were active in vivo in a mouse model of active sensitisation.

MATERIALS

Female Balb/c mice (6-8) per group were used for in vivo study.

TREATMENT

Mice were treated with active PS AS-ODNs determined in initial in vitro studies. Compounds were dosed daily (3-30mg/kg i.v.) over the course of sensitisation to ovalbumin.

METHODS

Stat6 mRNA and protein levels were determined in the spleen after treatment (quantitative northern and western analysis respectively), in addition to serum IgE (ELISA). ANOVA was used to determine any significant differences between groups.

RESULTS

Both of the AS-ODNs tested in vivo, down regulated Stat6 mRNA and protein levels in the spleen by 40-50% although there was no effect on serum IgE. These treatments also induced splenomegaly in vivo and caused splenocyte proliferation in vitro.

CONCLUSIONS

The AS-ODNs used can down regulate Stat6 mRNA and protein although not sufficiently to influence IgE-levels. These effects are likely to be complicated in vivo by the immune-stimulation evident as splenomegaly.

A small-to-large unit progression in metaphonological awareness and reading?

The paper reports a series of studies of reading and metaphonological processing by children in their second year in primary school (aged 6 years). An earlier study had established that, in the first year of learning, performance was characterized by a small-unit approach in which graphemes and phonemes were emphasized. In the second year, reading became more sensitive to the frequencies of rime structures in the lexicon. Capacity to generate word analogies for nonwords also showed increasing commitment to rime-based responses, and this trend was strongly linked to reading age. The present results suggest that a small-unit approach to reading is augmented by a large-unit approach as development proceeds. This trend was reflected in performance on a test of explicit phonological awareness. When asked to report the segment of sound shared by two spoken words, Primary 1 children were poor in reporting shared rimes but relatively adept in reporting shared phonemes. During Primary 2 there was an improvement in ability to report shared rimes, and this trend was also related to reading age. These results are discussed in relation to the influence of instruction and the nature of the orthography in determining the course of reading development.

Conservation of sequence and expression of Xenopus and zebrafish dHAND during cardiac, branchial arch and lateral mesoderm development

dHAND and eHAND are related basic helix-loop-helix transcription factors that are expressed in the cardiac mesoderm and in numerous neural crest-derived cell types in chick and mouse. To better understand the evolutionary development of overlapping expression and function of the HAND genes during embryogenesis, we cloned the zebrafish and Xenopus orthologues. Comparison of dHAND sequences in zebrafish, Xenopus, chick, mouse and human demonstrated conservation throughout the protein. Expression of dHAND in zebrafish was seen in the earliest precursors of all lateral mesoderm at early gastrulation stages. At neurula and later stages, dHAND expression was observed in lateral precardiac mesoderm, branchial arch neural crest derivatives and posterior lateral mesoderm. At looping heart stages, cardiac dHAND expression remained generalized with no apparent regionalization. Interestingly, no eHAND orthologue was found in zebrafish. In Xenopus, dHAND and eHAND were co-expressed in the cardiac mesoderm without the segmental restriction seen in mice. Xenopus dHAND and eHAND were also expressed bilaterally in the lateral mesoderm without any left-right asymmetry. Within the branchial arches, XdHAND was expressed in a broader domain than XeHAND, similar to their mouse counterparts. Together, these data demonstrate conservation of HAND structure and expression across species.

Do psychosocial variables predict the physical growth of infants with orofacial clefts?

This study sought to determine whether psychosocial variables (parent-infant feeding interactions, infant temperament, maternal social support, family socioeconomic status) are important in predicting the physical growth of infants with orofacial clefts, after controlling for selected medical variables (infant health status, cleft diagnosis, and previous weight). Infant growth (weight-to-height zscores) was tracked for 2 years, and models were developed to predict growth at 3, 12, and 24 months. The authors also examined the growth trajectories of infants with different cleft types: cleft lip and palate (CLP) and cleft palate only (CPO). CPO infants showed some increase in their growth relative to the population mean over time, whereas the growth of CLP infants remained lower than the population mean at all time points. After controlling for medical variables, psychosocial variables collectively accounted for an additional 42% of the variance in infants' growth at 3 months of age, but they did not account for growth at 12 months and 24 months, largely due to the strong effect of previous growth. The authors tentatively conclude that psychosocial variables influence the early growth trajectory of infants with clefts, but subsequent growth becomes increasingly regulated by biological factors.

The violent patient

Encounters with violent behavior are an inevitable part of working in emergency departments. By adoption of a cohesive, multidisciplinary approach to behavioral decompensation, as is done in preparation for airway compromise, the risk for injury to patients and staff is minimized. As with airway compromise, anticipation of and preparation for deterioration can avoid the necessity of the most invasive measures and can ensure a calm, positive outcome. With the appropriate knowledge, teamwork, and skills, even patients requiring the most intensive intervention can be treated safely and professionally.

Cyclotron resonance in the layered perovskite superconductor Sr2RuO4

We have observed cyclotron resonance in the layered perovskite superconductor Sr2RuO4. We obtain cyclotron masses for the alpha, beta, and gamma Fermi surfaces of (4.33+/-0.05)m(e), (5.81+/-0. 05)m(e), and (9.71+/-0.2)m(e), respectively. The appreciable differences between these results and those obtained from de Haas-van Alphen measurements are attributable to strong electron-electron interactions in this system. Our findings appear to be consistent with predictions for an interacting Fermi liquid; indeed, semiquantitative agreement is obtained for the electron pockets beta and gamma.

Mutation of cytochrome bd quinol oxidase results in reduced stationary phase survival, iron deprivation, metal toxicity and oxidative stress in Azotobacter vinelandii

Azotobacter vinelandii cydAB mutants lacking cytochrome bd lost viability in stationary phase, irrespective of temperature, but microaerobiosis or iron addition to stationary phase cultures prevented viability loss. Growth on solid medium was inhibited by a diffusible factor from neighbouring cells, and by iron chelators, In(III) or Ga(III); microaerobic growth overcame inhibition by the extracellular factor. Siderophore production and total Fe(III)-chelating activity were not markedly affected in Cyd(-) mutants, and remained responsive to iron repression. Cyd(-) mutants were hypersensitive to Cu(II), Zn(II), and compounds exerting oxidative stress. Failure to synthesise haemoproteins does not explain the complex phenotype since mutants retained significant catalase activity. We hypothesise that Cyd(-) mutants are defective in maintaining the near-anoxic cytoplasm required for reductive iron metabolism and nitrogenase activity.

Cognitive and psychomotor development of infants with orofacial clefts

OBJECTIVE

To compare at ages 3, 12, and 24 months the cognitive and psychomotor development of 29 infants with cleft lip and palate (CLP), 28 infants with cleft palate only (CPO), and a demographically matched comparison (COMP) group of 69 infants; to examine predictors of cognitive status at age 24 months in the cleft group.

METHODS

Infants were administered the Bayley Scales of Infant Development (BSID), mother-infant interactions were observed, and medical records were reviewed.

RESULTS

CLP and CPO groups scored lower than the COMP group on the BSID, but did not differ from one another. Cleft group infants scored lower than COMP group infants on BSID items assessing nonverbal and expressive language skills. Quality of maternal interaction predicted the 2-year Mental Development Index (MDI) scores of infants with clefts.

CONCLUSIONS

Infants with clefts show relative deficits in cognitive and psychomotor development. Cognitive deficits are apparent in nonverbal as well as verbal areas of performance.

Flutamide, testolactone, and reduced hydrocortisone dose maintain normal growth velocity and bone maturation despite elevated androgen levels in children with congenital adrenal hyperplasia

Treatment outcome in congenital adrenal hyperplasia is often sub-optimal due to hyperandrogenism, treatment-induced hypercortisolism, or both. We previously reported better control of linear growth, weight gain, and bone maturation in a short term cross-over study of a new four-drug treatment regimen containing an antiandrogen (flutamide), an inhibitor of androgen to estrogen conversion (testolactone), reduced hydrocortisone dose, and fludrocortisone, compared to the effects of a control regimen of hydrocortisone and fludrocortisone. Twenty-eight children have completed 2 yr of follow-up in a subsequent long term randomized parallel study comparing these two treatment regimens. During 2 yr of therapy, compared to children receiving hydrocortisone, and fludrocortisone treatment, children receiving flutamide, testolactone, reduced hydrocortisone dose (average of 8.7 +/- 0.6 mg/m2 x day), and fludrocortisone had significantly (P < or = 0.05) higher plasma 17-hydroxyprogesterone, androstenedione, dehydroepiandrosterone, dehydroepiandrosterone sulfate, and testosterone levels. Despite elevated androgen levels, children receiving the new treatment regimen had normal linear growth rate (at 2 yr, 0.1 +/- 0.5 SD units), and bone maturation (at 2 yr, 0.7 +/- 0.3 yr bone age/yr chronological age). No significant adverse effects were observed after 2 yr. We conclude that the regimen of flutamide, testolactone, reduced hydrocortisone dose, and fludrocortisone provides effective control of congenital adrenal hyperplasia with reduced risk of glucocorticoid excess. A long term study of this new regimen is ongoing.

A series of outbreaks of food poisoning?

A series of independently occurring episodes which were notified individually as 'food poisoning' were, after investigation, linked to a common source water supply.

Regulation of cytochrome bd expression in the obligate aerobe Azotobacter vinelandii by CydR (Fnr). Sensitivity to oxygen, reactive oxygen species, and nitric oxide

Azotobacter vinelandii is an obligately aerobic bacterium in which aerotolerant nitrogen fixation requires cytochrome bd. Regulation of cytochrome bd expression is achieved by CydR (an Fnr homologue), which represses transcription of the oxidase genes cydAB. cydAB mRNA was mapped by primer extension; the transcriptional start site was determined, and putative -10 and -35 regions were deduced. Two "CydR boxes," one at the +1 site and one upstream of the -35 region, were identified. Transcriptionally inactive, purified CydR was converted, by adding NifS, cysteine, and Fe(2+), into an active form possessing acid-labile sulfide and spectra suggesting a [4Fe-4S](2+) cluster. Reconstituted CydR specifically bound both CydR boxes cooperatively, with higher affinity for the nearer consensus +1 site. Low concentrations of O(2) or NO ([O(2)]/[[CydR] or [NO]/[CydR] = 0.1-0. 6) elicited loss of the 420 nm absorbance attributed to the [4Fe-4S](2+) cluster, formation of a 315 nm species, and loss of ability to retard DNA migration. Retardation by reconstituted CydR was enhanced by superoxide dismutase and/or catalase, suggesting a role for reactive oxygen species in CydR inactivation. The role of CydR in regulating cydAB expression in the supposedly anoxic cytoplasm of A. vinelandii and similarities to cydAB regulation by Fnr in Escherichia coli are discussed.

A pilot study to evaluate the effects of floatation spa treatment on patients with osteoarthritis

OBJECTIVE

To conduct a preliminary investigation of the effects on floatation spa therapy on quality of life in patients with osteoarthritis to see if controlled trials are warranted.

DESIGN

Uncontrolled clinical trial.

SETTING

Private floatation spa therapy centre.

PATIENTS

Fourteen patients with chronic osteoarthritis of the weight-bearing joints, of whom four dropped out.

INTERVENTION

Six weekly sessions of floatation spa therapy.

OUTCOME MEASURES

SF36, AIMS2 and MYMOP quality-of-life questionnaires.

MAIN RESULTS

All patients improved. Differences between baseline and discharge scores showed statistically significant improvement for MYMOP, but not AIMS2 or SF-36.

CONCLUSIONS

Controlled trials of floatation spa therapy for patients with osteoarthritis are warranted.

Homologous human and murine antisense oligonucleotides targeting stat6. Functional effects on germline cepsilon transcript

Interleukin (IL)-4 and (IL)-13 induce immunoglobulin (Ig)E synthesis via activation of the transcription factor signal transducer and activator of transcription (Stat)6. The present study describes the identification and characterization of antisense oligonucleotides to Stat6 as an approach to interrupt IL-4 and IL-13 signaling and thereby to attenuate germline Cepsilon transcription, a prerequisite to IgE synthesis. A limited gene-walk was performed with chemically modified oligonucleotides to identify sequences capable of downregulating both human and murine Stat6. A chimeric oligonucleotide (9b, base sequence GTGAGGTCCTGTTCAGTGGG) demonstrated high levels of antisense activity in both species. Further characterization of 9b showed a dose-dependent Stat6 messenger RNA (mRNA) and protein downregulation (concentration that produces 50% inhibition of effect = 168 and 215 nM, respectively) through a ribonuclease H-dependent antisense mechanism with no effect on closely related members of the Stat family. Further, pretreatment of DND39 cells (human Burkitt lymphoma cell line) with oligonucleotide 9b before IL-4 stimulation successfully downregulated germline Cepsilon transcription. Because Stat6 represents an attractive but technically challenging drug discovery target, antisense oligonucleotides may provide an alternative approach to low molecular-weight compounds for inhibiting IL-4 and IL-13 signaling.

Ultrasound densitometry of the os calcis in patients with hemiparesis following a cerebrovascular accident

Ultrasound densitometry has been measured in the os calcis of 31 stroke patients (14 women, 17 men), ages 46-87 years, to determine whether bone density is lower than expected for normal subjects at this site, and to investigate whether or not the stroke side has lower values than the nonstroke side. We have also measured a large control group of 268(39 men, 228 women) subjects who showed similar values to other published data. Immobility is a known precursor to bone loss and so we also compared ultrasound Stiffness Index with an index of mobility in 22 of the stroke patients. In healthy subjects, ultrasound densitometry (measured as Stiffness) fell by 25% in females from 48-52 to 68-72 years. Stiffness (expressed as z-score) in patients with stroke was low in females (P < 0.02) but not in males, but both stroke side and nonstroke side were equally low. Stiffness did not decline with time since stroke, but did correlate with mobility after stroke, on the stroke (r = 0.73) and nonstroke (r = 0.62) side. The data suggest that stroke patients, particularly females, have low bone density before the stroke event. The greater ultrasound Stiffness with increasing mobility after stroke may suggest that active rehabilitation after stroke may produce denser bone.