Argon laser peripheral iridoplasty (ALPI) versus systemic intraocular pressure lowering medications as the immediate management for phacomorphic angle closure

Poster Session: Glaucoma PhenotypesPurpose: To compare the efficacy and safety of argon laser peripheral iridoplasty (ALPI) to systemic intraocular pressure (IOP) lowering medications in the immediate management of phacomorphic angle closure. Patients and methods: This was a prospective randomized controlled study conducted at a district hospital in Hong Kong, China. Consecutive cases of phacomorphic angle closure were recruited from December 2009 to December 2010. Patients received intravenous (IV) and oral carbonic anhydrase inhibitor or ALPI as the initial treatment. IV mannitol was administered in both groups for presenting IOP > 60 mmHg or IOP > 40 mmHg 2 hours post treatment. The following perimeters were compared between the 2 arms: Snellen best correct visual acuity (BCVA); duration of symptoms; presenting IOP; IOP at 15 minutes, 30minutes and hourly after treatment until IOP < 25 mmHg; post-op angle, retinal nerve fibre layer (RNFL), endothelial count, BCVA and IOP. Results: Ten consecutive cases were included in the study. Six cases received medication therapy and 4 received ALPI. The mean age was 79.7 ± 7.2 in the medical therapy group and 78.3 ± 11.0 in the ALPI group. The presenting IOP was 50.7 ± 8.4 mmHg and 50.25 ± 6.9 mmHg in the medical therapy and ALPI group respectively. The duration of phacomorphic glaucoma in the medical group was 2.8 ± 3.5 days and 0.9 ± 0.25 days in the ALPI group. In the medical therapy group, 50% (3/6) required IV mannitol and none in the ALPI group. The time taken to reduce the presenting IOP to < 25 mmHg was 115.0 ± 97.0 minutes in the medical therapy group and 18.8 ± 7.5 minutes in the ALPI group. Within the first 30minutes, the drop in IOP was 20.8 ± 13.5mmHg in the medical group and 34.8 ± 3.2mmHg in the ALPI group, representing a 41.0% and 69.3% drop in IOP respectively. The degree of peripheral anterior synechiae (PAS) formation at 3 months was 45 ± 45.3° and 22.5 ± 5° in the medical and ALPI group respectively. The RNFL, angle, endothelial count, post-op VA and IOP were comparable in both groups. Conclusion: ALPI is an effective and safe IOP lowering modality in acute phacomorphic angle closure, offering a more rapid reduction of IOP, avoiding the use of systemic carbonic anhydrase inhibitor and hyperosmotic agents, and with seemingly less PAS formation and comparable post-op results as compared to medical therapy. ALPI should replace medical therapy as first line treatment in phacomorphic angle closure especially in elderly patients cannot tolerable the side effects of systemic IOP-lowering medication.published_or_final_versio

Needs and preferences for technology among Chinese family caregivers of persons with dementia: a pilot study

Background: Dementia is a major public health concern associated with significant caregiver demands and there are technologies available to assist with caregiving. However, there is a paucity of information on caregiver needs and preferences for these technologies, especially among Chinese family caregivers of persons with dementia in Canada. Objective: The purpose of this study was to examine the technology needs and preferences of Chinese family care- givers of persons with dementia with a sex and gender lens in Canada. Methods: A cross-sectional survey was conducted through the Yee Hong Centre of Geriatric Care in Canada. Frequency distributions, Wilcoxon Signed Ranks Test, and multiple regression analyses were performed. Results: The majority of the 40 respondents did not demonstrate knowledge about technology to assist with caregiving. Ease of installation and reliability were identified as the most important features when installing and using technology respectively. Respondents demonstrated a positive attitude towards the use of technology during caregiving. Controlling for age, female respondents were significantly more receptive of technology. Conclusions: Our findings suggest a need to increase awareness of technology options to assist caregiving in this ethnic population and provide insight for future development and marketing of technology that better align with caregivers’ needs

Demonstration of multi-channel 80 Gbit/s integrated transmitter and receiver for wavelength-division multiplexing passive optical network and fronthauling applications

The performance evaluation of a multi-channel transmitter that employs an arrayed reflective electroabsorption modulator-based photonic integrated circuit and a low-power driver array in conjunction with a multi-channel receiver incorporating a pin photodiode array and integrated arrayed waveguide grating is reported. Due to their small footprint, low power consumption and potential low cost, these devices are attractive solutions for future mobile fronthaul and next generation optical access networks. A BER performance of <10(-9) at 10.3 Gbit/s per channel is achieved over 25 km of standard single mode fibre. The transmitter/receiver combination can achieve an aggregate bit rate of 82.4 Gbit/s when eight channels are active

Frontal mucocele with an accompanying orbital abscess mimicking a fronto-orbital mucocele: case report

BACKGROUND: Mucoceles are slowly expanding cystic lesions with respiratory epithelium containing mucus most commonly affecting the frontal and ethmoidal sinuses. They are caused by obstruction of sinus ostium. Mucoceles exert pressure on the bony boundaries and due to the proximity to the brain and orbit extension to these areas are common. CASE PRESENTATION: A case of a frontal mucocele with an accompanying orbital abscess mimicking a fronto-orbital mucocele is reported. A 77 year old female patient suffering from left sided proptosis and pain around the left eye was admitted to our department. She had a history of left frontal sinus mucocele one year ago that was offered an osteoplastic frontal sinus surgery that the patient refused. Patient had limitation of eye movements. Fundoscopic examination revealed a minimal papilledema. Coronal computerized tomography and orbital magnetic resonance imaging showed a frontal mucocele with suspicious erosion of the orbital roof and a superiorly localized extraconal mass displacing the orbit lateroinferiorly. Frontal and orbital masses had similar intensities. Thus surgery was planned for a fronto-orbital mucocele. During surgery no defect was found on the orbital roof. Frontal mucocele and orbital cystic mass was removed separately. Pathological examination showed a frontal mucocele and an orbital abscess wall. Postoperatively eye movements returned to normal and papilledema resolved. CONCLUSION: Fronto-orbital mucoceles are commonly encountered pathologies, but frontal mucocele with an orbital abscess is a rarely seen and should be kept in mind because their treatments differ

Bistability in Apoptosis by Receptor Clustering

Apoptosis is a highly regulated cell death mechanism involved in many physiological processes. A key component of extrinsically activated apoptosis is the death receptor Fas, which, on binding to its cognate ligand FasL, oligomerize to form the death-inducing signaling complex. Motivated by recent experimental data, we propose a mathematical model of death ligand-receptor dynamics where FasL acts as a clustering agent for Fas, which form locally stable signaling platforms through proximity-induced receptor interactions. Significantly, the model exhibits hysteresis, providing an upstream mechanism for bistability and robustness. At low receptor concentrations, the bistability is contingent on the trimerism of FasL. Moreover, irreversible bistability, representing a committed cell death decision, emerges at high concentrations, which may be achieved through receptor pre-association or localization onto membrane lipid rafts. Thus, our model provides a novel theory for these observed biological phenomena within the unified context of bistability. Importantly, as Fas interactions initiate the extrinsic apoptotic pathway, our model also suggests a mechanism by which cells may function as bistable life/death switches independently of any such dynamics in their downstream components. Our results highlight the role of death receptors in deciding cell fate and add to the signal processing capabilities attributed to receptor clustering.Comment: Accepted by PLoS Comput Bio

Hypoxia causes transgenerational impairments in reproduction of fish

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Algorithm for multi-curve-fitting with shared parameters and a possible application in evoked compound action potential measurements

BACKGROUND: Experimental results are commonly fitted by determining parameter values of suitable mathematical expressions. In case a relation exists between different data sets, the accuracy of the parameters obtained can be increased by incorporating this relationship in the fitting process instead of fitting the recordings separately. METHODS: An algorithm to fit multiple measured curves simultaneously was developed. The method accounts for parameters that are shared by some curves. It can be applied to either linear or nonlinear equations. Simulated noisy "measurement results" were created to compare the introduced method to the "straight forward" way of fitting the curves separately. RESULTS: The analysis of the simulated measurements confirm, that the introduced method yields more accurate parameters compared to the ones gained by fitting the measurements separately. Therefore it needs more computer time. As an example, the new fitting algorithm is applied to the measurements of the evoked compound action potentials (ECAP) of the auditory nerve: This leads to promising ideas to reduce artefacts generated by the measuring process. CONCLUSION: The introduced fitting algorithm uses the relationship between multiple measurement results to increase the accuracy of the parameters. Its application in the field of ECAP measurements is promising and should be further investigated

52-week efficacy and safety of telbivudine with conditional tenofovir intensification at week 24 in HBeAg-positive chronic Hepatitis B

Background and Aims: The Roadmap concept is a therapeutic framework in chronic hepatitis B for the intensification of nucleoside analogue monotherapy based on early virologic response. The efficacy and safety of this approach applied to telbivudine treatment has not been investigated. Methods: A multinational, phase IV, single-arm open-label study (ClinicalTrials.gov ID NCT00651209) was undertaken in HBeAg-positive, nucleoside-naive adult patients with chronic hepatitis B. Patients received telbivudine (600 mg once-daily) for 24 weeks, after which those with undetectable serum HBV DNA (<300 copies/mL) continued to receive telbivudine alone while those with detectable DNA received telbivudine plus tenofovir (300 mg once-daily). Outcomes were assessed at Week 52. Results: 105 patients commenced telbivudine monotherapy, of whom 100 were included in the efficacy analysis. Fifty-five (55%) had undetectable HBV DNA at Week 24 and continued telbivudine monotherapy; 45 (45%) received tenofovir intensification. At Week 52, the overall proportion of undetectable HBV DNA was 93% (93/100) by last-observation-carried-forward analysis (100% monotherapy group, 84% intensification group) and no virologic breakthroughs had occurred. ALT normalization occurred in 77% (87% monotherapy, 64% intensification), HBeAg clearance in 43% (65% monotherapy, 16% intensification), and HBeAg seroconversion in 39% (62% monotherapy, 11% intensification). Six patients had HBsAg clearance. Myalgia was more common in the monotherapy group (19% versus 7%). No decrease in the mean glomerular filtration rate occurred in either treatment group at Week 52. Conclusions: Telbivudine therapy with tenofovir intensification at Week 24, where indicated by the Roadmap strategy, appears effective and well tolerated for the treatment of chronic hepatitis B. Trial Registration: ClinicalTrials.gov NCT0065120

Varicella-Zoster viruses associated with post-herpetic neuralgia induce sodium current density increases in the ND7-23 Nav-1.8 neuroblastoma cell line

Post-herpetic neuralgia (PHN) is the most significant complication of herpes zoster caused by reactivation of latent Varicella-Zoster virus (VZV). We undertook a heterologous infection in vitro study to determine whether PHN-associated VZV isolates induce changes in sodium ion channel currents known to be associated with neuropathic pain. Twenty VZV isolates were studied blind from 11 PHN and 9 non-PHN subjects. Viruses were propagated in the MeWo cell line from which cell-free virus was harvested and applied to the ND7/23-Nav1.8 rat DRG x mouse neuroblastoma hybrid cell line which showed constitutive expression of the exogenous Nav 1.8, and endogenous expression of Nav 1.6 and Nav 1.7 genes all encoding sodium ion channels the dysregulation of which is associated with a range of neuropathic pain syndromes. After 72 hrs all three classes of VZV gene transcripts were detected in the absence of infectious virus. Single cell sodium ion channel recording was performed after 72 hr by voltage-clamping. PHN-associated VZV significantly increased sodium current amplitude in the cell line when compared with non-PHN VZV, wild-type (Dumas) or vaccine VZV strains ((POka, Merck and GSK). These sodium current increases were unaffected by acyclovir pre-treatment but were abolished by exposure to Tetrodotoxin (TTX) which blocks the TTX-sensitive fast Nav 1.6 and Nav 1.7 channels but not the TTX-resistant slow Nav 1.8 channel. PHN-associated VZV sodium current increases were therefore mediated in part by the Nav 1.6 and Nav 1.7 sodium ion channels. An additional observation was a modest increase in message levels of both Nav1.6 and Nav1.7 mRNA but not Nav 1.8 in PHN virally infected cells

Lack of Cardiac Nerve Sprouting after Intramyocardial Transplantation of Bone Marrow-Derived Stem Cells in a Swine Model of Chronic Ischemic Myocardium

Previous experimental studies suggested that mesenchymal stem cell transplantation causes cardiac nerve sprouting; however, whether bone marrow (BM)-derived mononuclear cells (MNC) and endothelial progenitor cells (EPC) can also lead to cardiac nerve sprouting and alter gap junction expression remains unclear. We investigated the effect of electroanatomical mapping-guided direct intramyocardial transplantation of BM-MNC (n = 8) and CD31+EPC (n = 8) compared with saline control (n = 8) on cardiac nerve sprouting and gap junction expression in a swine model of chronic ischemic myocardium. At 12 weeks after transplantation, the distribution and density of cardiac nerve sprouting were determined by staining of tyrosine hydroxylase (TH) and growth associated protein 43(GAP-43) and expression of connexin 43 in the targeted ischemic and remote normal myocardium. After 12 weeks, no animal developed sudden death after the transplantation. There were no significant differences in the number of cells with positive staining of TH and GAP-43 in the ischemic and normal myocardium between three groups. Furthermore, expression of connexin 43 was also similar in the ischemic and normal myocardia in each group of animals (P > 0.05). The results of this study demonstrated that intramyocardial BM-derived MNC or EPC transplantation in a large animal model of chronic myocardial ischemia was not associated with increased cardiac nerve sprouting over the ischemic myocardium