Identification of multiple Gypsy LTR-retrotransposon lineages in vertebrate genomes

Gypsy LTR-retrotransposons have been identified in the genomes of many organisms, but only a small number of vertebrate examples have been reported to date. Here we show that members of this family are likely to be widespread in many vertebrate classes with the possible exceptions of mammals and birds. Phylogenetic analyses demonstrate that although there are several distinct lineages of vertebrate gypsy LTR-retrotransposons, the majority clusters into one monophyletic clade. Groups of fungal, plant, and insect elements were also observed, suggesting horizontal transfer between phyla may be infrequent. However, in contrast to this, there was little evidence to support sister relationships between elements derived from vertebrate and insect hosts. In fact, the majority of the vertebrate elements appeared to be most closely related to a group of gypsy LTR-retrotransposons present within fungi. This implies either that at least one horizontal transmission between these two phyla has occurred previously or that a gypsy LTR-retrotransposon lineage has been lost from insect taxa.

Use of contrast-enhanced ultrasound in follow-up after endovascular aortic aneurysm repair

PURPOSE

To investigate the use of contrast-enhanced ultrasound in the detection of endoleak after endovascular repair of abdominal aortic aneurysm.

MATERIALS AND METHODS

Eighteen patients underwent follow-up on 20 occasions after endovascular aortic aneurysm repair by arterial-phase contrast-enhanced spiral computed tomography (CT). All patients had unenhanced color Doppler ultrasound and Levovist-enhanced ultrasound on the same day. The ultrasound examinations were reported in a manner that was blind to the CT results. CT was regarded as the gold standard for the purposes of the study.

RESULTS

There were three endoleaks shown by CT. Unenhanced ultrasound detected only one endoleak (sensitivity, 33%). Levovist-enhanced ultrasound detected all three endoleaks (sensitivity, 100%). Levovist-enhanced ultrasound indicated an additional six endoleaks that were not confirmed by CT (specificity, 67%; positive predictive value, 33%). In one of these six cases, the aneurysm increased in size, which indicates a likelihood of endoleak. Two of the remaining false-positive results occurred in patients known to have a distal implantation leak at completion angiography.

CONCLUSION

In this small group of patients, contrast-enhanced ultrasound appears to be a reliable screening test for endoleak. The false-positive results with enhanced ultrasound may be due to the failure of CT to detect slow flow collateral pathways. Although the number of patients in this study is small, enhanced ultrasound may be more reliable than CT in detecting endoleak.

Sleep in the elderly

Older adults frequently experience difficulties with sleep that can be caused by specific sleep disorders (such as sleep-disordered breathing or periodic limb movements in sleep) and circadian rhythm disturbances. These all can be effectively treated. Medical illnesses and medications also can have a negative affect on sleep and effective management of these can significantly improve sleep in older adults. Sleep in institutionalized older adults is even more disturbed than sleep of community-dwelling older people and special considerations can be made to improve the quality of sleep in institutional settings.

Divergent effects of paracetamol on reactive oxygen intermediate and reactive nitrogen intermediate production by U937 cells

We investigated the effects of paracetamol on reactive oxygen intermediate and reactive nitrogen intermediate production by U937 cells. Cells which had been treated with paracetamol (0.01 microM - 10 microM) exhibited a significant (p<0.001) increase in hydrogen peroxide production and a significant (p<0.001) increase in phorbol 12-myristate 13-acetate induced superoxide production. Conversely, paracetamol (0.01 microM - 10 microM) caused a significant (p<0.001) decrease in the amount of nitrite secreted into the culture medium. Our results indicate divergent effects of paracetamol on ROI and RNI production.

Second-harmonic generation in waveguides induced by photorefractive spatial solitons

We demonstrate experimentally second-harmonic generation in waveguides induced by photorefractive solitons and show that the conversion efficiency is improved considerably. These induced waveguides are flexible and can be generated in any crystalline direction that allows soliton formation, and thus offer broad tunability (by rotation of the crystal), which cannot exist in fabricated waveguides.

Human transcription factor hTAF(II)150 (CIF150) is involved in transcriptional regulation of cell cycle progression

Here we present evidence that CIF150 (hTAF(II)150), the human homolog of Drosophila TAF(II)150, plays an important and selective role in establishing gene expression patterns necessary for progression through the cell cycle. Gel filtration experiments demonstrate that CIF150 (hTAF(II)150) seems to be less tightly associated with human transcription factor IID than hTAF(II)130 is associated with hTAF(II)250. The transient functional knockout of CIF150 (hTAF(II)150) protein led to cell cycle arrest at the G(2)/M transition in mammalian cell lines. PCR display analysis with the RNA derived from CIF150-depleted cells indicated that CIF150 (hTAF(II)150) is required for the transcription of only a subset of RNA polymerase II genes. CIF150 (hTAF(II)150) directly stimulated cyclin B1 and cyclin A transcription in cotransfection assays and in vitro assays, suggesting that the expression of these genes is dependent on CIF150 (hTAF(II)150) function. We defined a CIF150 (hTAF(II)150) consensus binding site and demonstrated that a CIF150-responsive cis element is present in the cyclin B1 core promoter. These results suggest that one function of CIF150 (hTAF(II)150) is to select specific RNA polymerase II core promoter elements involved in cell cycle progression.

Melanin-concentrating hormone is the cognate ligand for the orphan G-protein-coupled receptor SLC-1

The underlying causes of obesity are poorly understood but probably involve complex interactions between many neurotransmitter and neuropeptide systems involved in the regulation of food intake and energy balance. Three pieces of evidence indicate that the neuropeptide melanin-concentrating hormone (MCH) is an important component of this system. First, MCH stimulates feeding when injected directly into rat brains; second, the messenger RNA for the MCH precursor is upregulated in the hypothalamus of genetically obese mice and in fasted animals; and third, mice lacking MCH eat less and are lean. MCH antagonists might, therefore, provide a treatment for obesity. However, the development of such molecules has been hampered because the identity of the MCH receptor has been unknown until now. Here we show that the 353-amino-acid human orphan G-protein-coupled receptor SLC-1 expressed in HEK293 cells binds MCH with sub-nanomolar affinity, and is stimulated by MCH to mobilize intracellular Ca2+ and reduce forskolin-elevated cyclic AMP levels. We also show that SLC-1 messenger RNA and protein is expressed in the ventromedial and dorsomedial nuclei of the hypothalamus, consistent with a role for SLC-1 in mediating the effects of MCH on feeding.

Self-immolative anthracycline prodrugs for suicide gene therapy

Four novel potential prodrugs derived from daunorubicin (8, 10) and doxorubicin (12, 14) were designed and synthesized. They are self-immolative prodrugs for suicide gene therapy activation by the enzyme carboxypeptidase G2 (CPG2) subsequently releasing the corresponding anthracyclines, by a 1,6-elimination mechanism. A mammary carcinoma cell line (MDA MB 361) was engineered to express CPG2 intracellularly (CPG2) or extracellularly, tethered to the outer cell membrane (stCPG2(Q)3). The prodrugs derived from doxorubicin showed prodrug/drug cytotoxicity differentials of 21-fold (compound 12) and 23-fold (compound 14). Prodrug 12 underwent an 11-fold activation when assayed in the cell line expressing externally surface-tethered CPG2.

Potential acuity pinhole: a simple method to measure potential visual acuity in patients with cataracts, comparison to potential acuity meter

OBJECTIVE

To describe the potential acuity pinhole (PAP) test and compare its accuracy to the potential acuity meter (PAM) in predicting visual outcome after cataract surgery.

STUDY DESIGN

Prospective case series.

PARTICIPANTS

A total of 56 preoperative patients with cataracts participated.

MAIN OUTCOME MEASURES

Accuracy of predicting postoperative distance visual acuity was measured.

METHODS

Lines of inaccuracy were calculated by subtracting actual postoperative best-corrected distance visual acuity (BCVA) from predicted values. Variables analyzed were method of prediction, preoperative BCVA, and preoperative spherical equivalent.

RESULTS

The PAP test predicted visual outcomes within 2 lines in 100%, 100%, and 56% of eyes with preoperative BCVA of 20/50 and better (group 1), 20/60 to 20/100 (group II), and 20/200 and worse (group III), respectively. The PAM predictions within 2 lines for the same groups were 42%, 47%, and 0%, respectively. Mean lines of inaccuracy of PAP predictions were 0.83, 1.11, and 3.50 lines for groups I, II, and III, respectively. Mean lines of inaccuracy for PAM predictions were 2.50, 2.68, and 6.22 lines for the same groups. Differences in lines of prediction between PAM and PAP were 1.67 (P = 0.004), 1.58 (P = 0.0002), and 2.72 lines (P = 0.0001) for groups I, II, and III, respectively. There was no statistically significant correlation between PAP predictions and preoperative myopic spherical equivalent.

CONCLUSIONS

The PAP test is a simple, inexpensive, and relatively reliable method to estimate visual outcome after uncomplicated cataract surgery in eyes with no coexisting disease. It is less accurate in patients with preoperative BCVA worse than 20/200. It appears to be more predictive than PAM.

Transmyocardial laser revascularization: experimental studies in healthy porcine myocardium

BACKGROUND

Clinical studies have demonstrated a significant reduction of cardiac index shortly after transmyocardial laser revascularization in patients with low ejection fraction. We analyzed the influence of transmyocardial laser revascularization on healthy myocardium in pigs.

METHODS

Carbon dioxide channels were created in 20 pigs which were observed for 6 hours. Ten pigs received one laser channel and ten pigs two laser channels per cm2 in the left anterior descending artery region. Seven pigs served as controls. Perfusion (microspheres), function, histochemical, and histologic assessments were subsequently performed.

RESULTS

A significant deterioration of left ventricular stroke work index was observed shortly after transmyocardial laser revascularization in both laser groups (p < 0.05). After 6 hours the left ventricular stroke work index did not increase and showed significantly reduced values at rest (p < 0.05) and during stress in the laser groups (p < 0.01). Normal regional perfusion, small ischemic and necrotic areas, open laser channels in the left anterior descending artery region and significantly increased myocardial water content were observed in the laser groups (p < 0.01).

CONCLUSIONS

Carbon dioxide laser channels significantly decrease global heart function shortly after transmyocardial laser revascularization in healthy porcine myocardium. This myocardial tissue showed no recovery 6 hours postoperatively.

Successful orthotopic pig heart transplantation from non-heart-beating donors

BACKGROUND

With the aim to expand the severely limited donor pool by use of non-heart-beating donors we developed a technique for successful transplantation of hearts after 30 minutes of normothermic ischemia without donor pretreatment.

METHODS

In control groups hearts were transplanted in a conventional fashion using crystalloid cardioplegia (Group I, n = 6) or BCP (Group II, n = 8) for induction of cardiac arrest. In the ischemic groups hearts were harvested after 30 minutes of normothermic ischemia, perfused with blood cardioplegia (BCP) (Group III, n = 9) or BCP containing the Na(+)-H(+)-exchange inhibitor HOE 642 (Group IV, n = 8) and transplanted orthotopically.

RESULTS

All animals could be weaned from cardiopulmonary bypass. Low dose inotropic support was necessary in the ischemic groups only. Recovery of the maximal left ventricular stroke work index (LVSWImax) in Groups I vs II was 62.6+/-19.6% vs 73.3+/-23.3% (NS), maximal right ventricular stroke work index (RVSWImax) averaged 61.1+/-18.8 vs 87.8+/-31.7% (NS) as compared to the preoperative level. In the ischemic groups (III vs IV) LVSWImax was 27.3+/-11.7 vs 59.5+/-32.4% (p = 0.038), RVSWImax was 27.4+/-20.9 vs 64.2+/-46.6% (NS).

CONCLUSIONS

The results indicate that (a) successful pig heart transplantation after 30 minutes of normothermic ischemia is possible without donor pretreatment, and (b) that HOE 642 improves posttransplant LVSWImax significantly.

Sleep-disordered breathing and periodic limb movements in sleep in older patients with schizophrenia

BACKGROUND

Since the prevalence of both sleep-disordered breathing (SDB) and periodic limb movements in sleep (PLMS) increase with age, we explored whether older schizophrenia patients would have a high incidence of SDB and PLMS. Correlations between sleep and clinical variables were also examined.

METHODS

Fifty-two patients (mean age = 59.6 years, SD = 8.9) had their sleep/wake, respiration, and leg movements recorded using a modified Medilog/Respitrace portable recording system plus oximetry. A battery of clinical, psychosocial, and motor disturbance variables were collected by research center staff.

RESULTS

Forty-eight percent of these patients had at least 10 respiratory events per hour of sleep. These patients reported more symptoms of daytime sleepiness than patients with fewer than 10 events per hour. The relatively high prevalence of SDB in this group may contribute to overall sleep disturbances, and does not appear to be a result of high body mass index. Only 14% of the patients had at least five limb movements per hour of sleep, suggesting the prevalence of PLMS is much lower than expected in this age group. The number of leg jerks was inversely related to symptoms of tardive dyskinesia.

CONCLUSIONS

The disturbance of sleep in these patients may be due, in part, to SDB, but is unlikely due to PLMS.

[Transmyocardial laser revascularization]

The clinical experience with transmyocardial laser revascularization indicates that angina is relieved significantly, perfusion and treadmill tolerance are improved and hospital admissions are decreased. The exact mechanism for a laser revascularization linked improvement is still unknown. Transmyocardial laser revascularization should be used only in highly selected cases when conventional methods fail to improve patients symptoms. Further evaluation of the efficacy of the new indirect revascularization method in clinical (larger multicenter trials) and experimental studies to elucidate the mechanism of TMLR is warranted. Experimental long-term studies to explain the mechanism are in progress.

Precision and method bias of two assays for oestradiol: consequences for decisions in assisted reproduction

Oestradiol monitoring in assisted reproduction is empirical, with no proof of benefit. Precise oestradiol estimation will be an essential pre-requisite for high quality evaluation of possible differences between combined and ultrasound-only monitoring. Objectives of the present trial were independent method comparison and bias estimation of chemiluminescent immunoassay (CLIA) versus radioimmunoassay for oestradiol. In a prospective comparison, 505 consecutive samples were split and assayed concurrently. Precision (reproducibility), relative bias and logistics were analysed and compared to manufacturers' findings. Correlation between CLIA and radioimmunoassay was excellent. Positive bias with CLIA necessitated altering decision points for therapy. Precision (reproducibility) was superior with CLIA, making it an appropriate candidate method for future randomized trials of the effectiveness of combined oestradiol/ultrasound monitoring for assisted reproduction.

[Hyperreactive malarial splenomegaly in a European returning from Africa]

INTRODUCTION

Hyper-reactive malarial splenomegaly (HMS) syndrome related to abnormal immunologic response to repeated malarial infections is unusual in European expatriates.

EXEGESIS

We report the case of a 72-year-old white male patient who had been residing in the Congo and developed a typical clinical features of hyperactive malarial syndrome characterized by massive splenomegaly with hypersplenism, high titers of malarial IgM antibodies, IgM macroglobulinemia, liver and medullary lymphocytic proliferation, and a clinical and immunological response to long-term chloroquine therapy.

CONCLUSION

Criteria for the diagnosis of hyper-reactive malarial splenomegaly are useful. However, making a distinction from malignant lymphoproliferative disorders is difficult, as a sustained response to chloroquine is required. Therefore, chloroquine appears to have a regulatory effect on the immune system.