Staged coil embolisation for the management of persistent aneurysmal right subclavian artery

A 70-year-old patient, who had previously undergone open surgical repair of an aneurysmal aberrant right subclavian artery (ARSA), presented with recurrent symptoms and reperfusion of the aneurysm at the site of proximal ligation. This was successfully treated by a staged endovascular procedure.

PleurX drain use in the management of malignant ascites: safety, complications, long-term patency and factors predictive of success

OBJECTIVES

The aim of this article was to assess the success, safety, complication profile and factors associated with long-term patency of tunnelled peritoneal drains (PleurX) in the treatment of refractory malignant ascites.

METHODS

Over a 4-year period, 28 consecutive patients (32 drain insertions) with refractory malignant ascites were treated with a PleurX drain. The study group comprised 7 males and 21 females (mean age, 61 years). A combination of fluoroscopic and ultrasound guidance was used to insert 4 drains; the remaining 28 drains were inserted under ultrasound guidance alone. Patient history, biochemical profiles, pathological and procedural records and clinical follow-up until death were reviewed. Statistical analysis included multivariate logistic regression analysis and Kaplan-Meier curves (p<0.05 was considered significant).

RESULTS

There was a 100% technical success rate for the insertion of the drain; there were no procedure-related deaths and no major complications. Only minor complications were reported: three (10%) immediate; three (10%) early; and two (7%) late. Factors significantly associated with these complications included current chemotherapy, low haemoglobin levels, low albumin levels, high white cell count and high c-reactive protein levels. The length of time the drains remained in situ, and therefore patent, ranged from 5 to 365 days (mean, 113 days). Out of the original 28 tunnelled drains, 24 (86%) remained in situ and functioning until the patients' death. Four (14%) drains dislodged and a subsequent PleurX drain was inserted on the opposite side of the abdominal wall. These new drains remained patent until the patient's death. The annual event rate was 0.45 events per year. A comorbid diagnosis of renal disease or chemotherapy was significantly related to a decreased length of patency.

CONCLUSION

The use of tunnelled peritoneal drains is safe and effective and we would advocate their use as a first-line approach in patients with refractory malignant ascites. Care and regular follow-up is indicated following insertion of the drain in all patients, especially those on chemotherapy and those with a pre-procedure diagnosis of renal disease.

Outcome of elderly patients with oesophageal squamous cell carcinoma after surgery

Background

Oesophagectomy may have morbidity and mortality rates that severely compromise long-term survival in elderly patients. The aim of this study was to compare clinical outcomes in elderly patients with oesophageal squamous cell carcinoma (SCC) with those of younger controls.

Methods

Elderly patients at least 70 years old with oesophageal SCC were matched 1 : 1 with controls aged less than 70 years according to sex, tumour stage, tumour location, histological grade, surgical approach, completeness of resection and surgical period. Co-morbidities, surgical complications, surgical mortality and long-term survival were compared.

Results

One hundred and thirty-six patients were included in each group. Surgical mortality was greater in the elderly group (5·9 versus 0·7 per cent; P = 0·036). Overall and disease-specific 5-year survival rates were worse among patients aged at least 70 years (30·0 versus 41·8 per cent, and 31·5 versus 44·7 per cent respectively), as were 10-year rates (13·7 versus 26·4 per cent, and 20·2 versus 29·0 per cent). Disease-free survival rates after 5 years (24·0 versus 35·5 per cent) and 10 years (12·3 versus 24·3 per cent) were not statistically significant (P = 0·076).

Conclusion

Poor functional status may account for higher morbidity and mortality rates in elderly patients with oesophageal SCC. Acceptable perioperative mortality rates and substantial long-term survival can still be achieved. Elderly patients should not be denied oesophagectomy.

Plasticity at glycinergic synapses in dorsal cochlear nucleus of rats with behavioral evidence of tinnitus

Fifteen percent to 35% of the United States population experiences tinnitus, a subjective "ringing in the ears". Up to 10% of those afflicted report severe and disabling symptoms. Tinnitus was induced in rats using unilateral, 1 h, 17 kHz-centered octave-band noise (116 dB SPL) and assessed using a gap-startle method. The dorsal cochlear nucleus (DCN) is thought to undergo plastic changes suggestive of altered inhibitory function during tinnitus development. Exposed rats showed near pre-exposure auditory brainstem response (ABR) thresholds for clicks and all tested frequencies 16 weeks post-exposure. Sound-exposed rats showed significantly worse gap detection at 24 and 32 kHz 16 weeks following sound exposure, suggesting the development of chronic, high frequency tinnitus. Message and protein levels of alpha(1-3,) and beta glycine receptor subunits (GlyRs), and the anchoring protein, gephyrin, were measured in DCN fusiform cells 4 months following sound exposure. Rats with evidence of tinnitus showed significant GlyR alpha(1) protein decreases in the middle and high frequency regions of the DCN while alpha(1) message levels were paradoxically increased. Gephyrin levels showed significant tinnitus-related increases in sound-exposed rats suggesting intracellular receptor trafficking changes following sound exposure. Consistent with decreased alpha(1) subunit protein levels, strychnine binding studies showed significant tinnitus-related decreases in the number of GlyR binding sites, supporting tinnitus-related changes in the number and/or composition of GlyRs. Collectively, these findings suggest the development of tinnitus is likely associated with functional GlyR changes in DCN fusiform cells consistent with previously described behavioral and neurophysiologic changes. Tinnitus related GlyR changes could provide a unique receptor target for tinnitus pharmacotherapy or blockade of tinnitus initiation.

High prevalence of risk behaviour concurrent with links to other high-risk populations: a potentially explosive HIV epidemic among men who have sex with men in Guangzhou, China

OBJECTIVES

HIV disproportionately affects men who have sex with men (MSM), but HIV prevalence among MSM in Guangzhou has not shown the rapid increasing trend as it has elsewhere in China. The aim of this study is to detect the epidemic and to determine the characteristics of MSM in Guangzhou susceptible to HIV.

METHODS

A cross-sectional survey with serological testing for HIV, syphilis, HBV and HCV through long-chain referral sampling strategy to help control the bias generated from non-statistic sampling.

RESULTS

The most important features of MSM in Guangzhou are being young and mobile, and of comparable education and income level to that of the general population. The HIV prevalence was 1.3% (95% CI 0.3 to 2.7%) in 2006. Many HIV risk factors were identified: low awareness of HIV risk perception and prevention, high prevalence of diverse, multiple partners and versatile sexual role, more than half of them actively having sex with women, low persistent condom use with both male and female partners, commercial sex and one out of 27 practising needle or syringe sharing during illicit drug use.

CONCLUSION

HIV has been introduced into MSM in Guangzhou. Demographic and behavioural risk factors and overlapping risk populations contribute to a potentially rapidly rising epidemic among MSM and the potential for a bridge to female partners in Guangzhou if timely and effective interventions are not implemented.

Age-related changes in glycine receptor subunit composition and binding in dorsal cochlear nucleus

Age-related hearing loss, presbycusis, can be thought of, in part, as a slow progressive peripheral deafferentation. Previous studies suggest that certain deficits seen in presbycusis may partially result from functional loss of the inhibitory neurotransmitter glycine in dorsal cochlear nucleus (DCN). The present study assessed age-related behavioral gap detection changes and neurochemical changes of postsynaptic glycine receptor (GlyRs) subunits and their anchoring protein gephyrin in fusiform cells of young (7-11 months) and aged (28-33 months) Fischer brown Norway (FBN) rats. Aged rats showed significantly (20-30 dB) elevated auditory brainstem-evoked response thresholds across all tested frequencies and worse gap detection ability compared to young FBN rats. In situ hybridization and quantitative immunocytochemistry were used to measure GlyR subunit message and protein levels. There were significant age-related increases in the alpha(1) subunit message with significant age-related decreases in alpha(1) subunit protein. Gephyrin message and protein showed significant increases in aged DCN fusiform cells. The pharmacologic consequences of these age-related subunit changes were assessed using [3H] strychnine binding. In support of the age-related decrease of alpha(1) subunit protein levels in DCN, there was a significant age-related decrease in the total number of GlyR binding sites with no significant change in affinity. These age-related changes may reflect an effort to reestablish a homeostatic balance between excitation and inhibition impacting on DCN fusiform cells by downregulation of inhibitory function in the face of an age-related loss of peripheral input. Age-related decrease in presynaptic glycine release results in altered subunit composition and this may correlate with loss of temporal coding of the aged fusiform cell in DCN. The previously reported role for gephyrin in retrograde intracellular receptor subunit trafficking could contribute to the alpha(1) decrease in the face of increased message.

Novel F-releasing composite with improved mechanical properties

In recent years, the authors have been developing novel fluoride-releasing dental composites containing ternary zirconium fluoride chelates. The aim of this study was to improve the physical and mechanical properties of these composites by improving the formulation of the monomers and photoinitiators. The hypothesis was that reduction of hydrophilic monomers and improvement of the photoinitiators could reduce water sorption and significantly increase the mechanical properties of the composite. The degree of conversion of the composites containing different compositions of photoinitiators was studied by Fourier transform near-infrared spectroscopy (FT-NIR). Ten experimental composites containing different compositions of ethoxylated bisphenol-A dimethacrylate (EBPADMA), 1,6-hexanediol dimethacrylate (HDDMA), triethylene glycol dimethacrylate (TEGDMA), and 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropoxy) phenyl]-propane (BisGMA) were tested for flexural strength, viscosity, and water sorption. The experimental composite containing 20% synthesized fluoride-releasing monomer, 30% BisGMA, 30% EBPADMA, and 20% HDDMA showed significantly higher fluoride release and recharge, but physical and mechanical properties similar to those of the control composite containing 40% BisGMA, 40% EBPADMA, and 20% HDDMA.

A novel mouse model of human breast cancer stem-like cells with high CD44+CD24-/lower phenotype metastasis to human bone

Abstract #4155

Background: At present, our understanding of the development of bone metastasis is limited. Therefore, little progress has been made in preventing skeletal metastasis in the breast cancer patient. A satisfactory animal model that avoids the species-specific factor and simultaneously shares similarities to the clinical pathophysiological progression of breast cancer metastasizing to bone is unavailable. A subpopulation (CD44+/CD24-/lower) of breast cancer cells possesses stem/progenitor cell properties (cancer stem-like cell). CD44 potentiates the adherence of metastatic breast cancer cells to bone marrow endothelial cells. In the present study, we used hepatocyte growth factor to enhance the proportion of CD44+/CD24-/lower subpopulation in the human breast cancer cell line MDA-MB-231. We used these human breast cancer stem-like cells and implantation of human bone to build a novel human-source model of human breast cancer skeletal metastasis.&#x2028; Methods: The human breast cancer cell line MDA-MB-231 was cultured in serum-free DMEM-F12 supplemented with growth factors. Cells in different subpopulations were separated by Percoll gradient centrifugation and incubated in the presence of 50 ng/mL hepatocyte growth factor. The proportion of CD44+/CD24-/lower subpopulation in the human breast cancer cell line MDA-MB-231 was detected with flow cytometry. Before injection with human breast cancer stem-like cells, the experimental animals were implanted with human bone in the right or left dorsal flanks. Animals in Groups A, B, and C were injected with 1 X 105, 1 X 106 human breast cancer stem-like cells, and 1 X 106 parental MDA-MB-231 cells, respectively. A positive control group (D) without implantation of human bone (non-human source model) was also injected with 1 X 106 MDA-MB-231 cells. A group of negative controls (E) with human bone implantation was injected with isotonic sodium chloride. For each group, Micro-SPECT was performed at weeks 4 and 7, and all animals were sacrificed at week 8. Immunohistochemistry was performed for CD34, CD105, SMA, CD44, CD24, CK, CXCR4, and OPN. mRNA levels of CD44, CD24, CXCR4, and OPN in bone metastasis tissues were analyzed by real-time quantitative polymerase chain reaction.&#x2028; Results: New vessels and connective tissue were found on the surface of implanted human bones and cells stained positive for antibodies against human CD105, SMA, and CD34, indicating that implanted human bones were viable and functional. Histologic and immunohistochemical analysis confirmed the metastases as cancer cells. Importantly, the results demonstrated that cells in implanted human bones of group B, which received 1 X 106 cancer stem-like cells, stained strongly positive for CD44, CXCR4, and OPN, whereas that of other groups showed no or minimum staining. Moreover, group B had the highest incidence of human bone metastasis (77.8%, P = 0.0230) and no accompaniment of other tissue metastasis. The real-time polymerase chain reaction (PCR) showed an increase of CD44 mRNA in metastatic bone tissues in group B compared with that of groups C and D (15.2- and 21.1-fold, respectively). The mRNA levels of CXCR4 and OPN (8.4- and 28.4-fold, respectively) in bone metastasis tissues of group B were all higher than that of groups C and D (4.8- and 11.6-fold; respectively). The levels of CD24 mRNA in group B were lowest, measuring only 30 percent of that in groups C and D.&#x2028; Conclusion: This study indicates that in the novel human source model of breast cancer, breast cancer stem-like cells demonstrate a higher human bone-seeking ability, which may contribute to increase metastasis incidence and attenuate species-specific influences. Its mechanism might be related to the higher expressions of CD44, CXCR4 and OPN, and the lower expression of CD24 in breast cancer stem-like cells. The model shares more similarities with clinical pathological features of bone metastatic patients. It will be helpful for further study of the mechanisms and subclinical diagnosis of bone metastasis.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4155.

First heart sound detection for phonocardiogram segmentation

This paper presents an algorithm for accurate and improved detection of the first heart sound S<inf>1</inf>for heart sound cardiac cycle segmentation under noisy environments. The proposed algorithm integrates an S<inf>1</inf>/S<inf>2</inf>selection step and an S<inf>1</inf>identification step. An adaptive sub-level tracking algorithm based on wavelet transform is proposed to separate the S<inf>1</inf>and S<inf>2</inf>from other components such as murmurs and noises. This is followed by a detection procedure based on Shannon energy to reject the overlapping interference so that the peaks of S<inf>1</inf>and S<inf>2</inf>can be detected. Criteria of time interval, energy and phonocardiogram (PCG) collecting position are used to identify S<inf>1</inf>with respect to the beginning of each cardiac cycle. Experimental results show that the proposed algorithm leads to an efficient segmentation of PCG cycle. Due to its simplicity and fast implementation, the method can be deployed clinically for further analysis and eventual use.

Regulation of vascular nitric oxide in vitro and in vivo; a new role for endogenous hydrogen sulphide?

BACKGROUND AND PURPOSE

The aim of these experiments was to evaluate the significance of the chemical reaction between hydrogen sulphide (H2S) and nitric oxide (NO) for the control of vascular tone.

EXPERIMENTAL APPROACH

The effect of sodium hydrosulphide (NaHS; H2S donor) and a range of NO donors, such as sodium nitroprusside (SNP), either alone or together, was determined using phenylephrine (PE)-precontracted rat aortic rings and on the blood pressure of anaesthetised rats.

KEY RESULTS

Mixing NaHS with NO donors inhibited the vasorelaxant effect of NO both in vitro and in vivo. Low concentrations of NaHS or H2S gas in solution reversed the relaxant effect of acetylcholine (ACh, 400 nM) and histamine (100 microM) but not isoprenaline (400 nM). The effect of NaHS on the ACh response was antagonized by CuSO(4) (200 nM) but was unaffected by glibenclamide (10 microM). In contrast, high concentrations of NaHS (200-1600 microM) relaxed aortic rings directly, an effect reduced by glibenclamide but unaffected by CuSO4. Intravenous infusion of a low concentration of NaHS (10 micromol kg(-1) min(-1)) into the anaesthetized rat significantly increased mean arterial blood pressure. L-NAME (25 mg kg(-1), i.v.) pretreatment reduced this effect.

CONCLUSIONS AND IMPLICATIONS

These results suggest that H2S and NO react together to form a molecule (possibly a nitrosothiol) which exhibits little or no vasorelaxant activity either in vitro or in vivo. We propose that a crucial, and hitherto unappreciated, role of H2S in the vascular system is the regulation of the availability of NO.

Examining the paradoxical relation between number of spikes and gaze amplitude in abducens neurons

During head-unrestrained gaze shifts, the number of spikes in the burst of abducens neurons increases with gaze amplitude, even when corrected for the component of the discharge related to the change in eye position. We examine this paradoxical dissociation between the number of spikes and eye amplitude, which occurs because eye amplitude in the head saturates for larger gaze shifts. First, we show that the extra spikes are unlikely to be due to antagonist muscle loading because the abducens neurons are completely silent during large gaze shifts when the muscle acts as an antagonist. Next, we divide the firing rate profile of abducens neurons into terms that represent signals related to eye position, velocity, and acceleration; a d.c. offset term specifying the firing associated with straight-ahead gaze; and a slide term, which compensates for the zero of the oculomotor plant. Then we examine the contribution of each term to the number of spikes recorded. A comparison of the number of spikes with the integral of the fitted function, combining all of the terms, for the duration of the burst reveals that the simulation captures much of the actual data. However, even a model with a slide term cannot reproduce the nonlinear relationship of the number of spikes with amplitude that characterizes large gaze shifts.

CSF hypocretin-1 levels in restless legs syndrome

CSF hypocretin-1 levels at 6 pm did not significantly differ between patients with restless legs syndrome (RLS) and control subjects as measured by direct radioimmunoassay and after acid extraction. The authors did not observe significant differences between early onset and late onset RLS. Hypocretin-1 levels did not correlate with RLS severity or polysomnographic measures. These results contrast with previous findings reporting significantly increased CSF hypocretin-1 in the late evening and mostly in early onset RLS.