Effect of light filters on reading speed in normal and low vision due to age-related macular degeneration

Purpose: To investigate the effects of light filters on reading speed in normal and low vision due to age-related macular degeneration (AMD). Methods: Reading speed was determined for 12 subjects with normal vision and 12 subjects with non-exudative AMD using stationary lowercase nonsensical print in Times Roman font and four light filters; a yellow Corning Photochromic Filter (CPF) 450, a grey neural density (ND) filter, an individual filter obtained using the Intuitive Colorimeter® and a clear filter. Results: There was no statistically significant light filter effect on reading speed for the normal subjects. The AMD group demonstrated a statistically significant 5% average improvement in reading speed with the CPF450 compared with the other filters although some AMD subjects had improvements of 10-15%. Conclusions: Light filters obtained using the Intuitive Colorimeter® performed poorly when compared with the CPF450, ND and clear filters for both the study groups. For the AMD group, average reading speed was statistically greater with the CPF450 than the other filters, however it is questionable whether the improvement (5%) would be clinically significant. As some of the subjects with AMD had greater improvements with the CPF450 we advocate clinical assessment of light filters using existing protocols on an individual basis. © 2004 The College of Optometrists.

The Val66Met polymorphism of the BDNF gene influences trigeminal Pain-Related evoked responses

Cortical pain processing is associated with large-scale changes in neuronal connectivity, resulting from neural plasticity phenomena of which brain-derived neurotrophic factor (BDNF) is a central driver. The common single nucleotide polymorphism Val66Met is associated with reduced BDNF activity. Using the trigeminal pain-related evoked potential (tPREP) to repeated electrical painful stimuli, we investigated whether the methionine substitution at codon 66 of the BDNF gene was associated with changes in cortical processing of noxious stimuli. Fifty healthy volunteers were genotyped: 30 were Val/Val and 20 were Met-carriers. tPREPs to 30 stimuli of the right supraorbital nerve using a concentric electrode were recorded. The N2 and P2 component latencies and the N2-P2 amplitude were measured over the 30 stimuli and separately, by dividing the measurements in 3 consecutive blocks of 10 stimuli. The average response to the 30 stimuli did not differ in latency or amplitude between the 2 genotypes. There was a decrease in the N2-P2 amplitude between first and third block in the Val/Val group but not in Met-carriers. BDNF Val66Met is associated with reduced decremental response to repeated electrical stimuli, possibly as a result of ineffective mechanisms of synaptic memory and brain plasticity associated with the polymorphism. PERSPECTIVE: BDNF Val66Met polymorphism affects the tPREP N2-P2 amplitude decrement and influences cortical pain processing through neurotrophin-induced neural plasticity, or through a direct BDNF neurotransmitter-like effect. Our findings suggest that upcoming BDNF central agonists might in the future play a role in pain management.

Early transplantation of mesenchymal stem cells after spinal cord injury relieves pain hypersensitivity through suppression of pain-related signaling cascades and reduced inflammatory cell recruitment

Bone marrow-derived mesenchymal stem cells (BMSC) modulate inflammatory/immune responses and promote motor functional recovery after spinal cord injury (SCI). However, the effects of BMSC transplantation on central neuropathic pain and neuronal hyperexcitability after SCI remain elusive. This is of importance because BMSC-based therapies have been proposed for clinical treatment. We investigated the effects of BMSC transplantation on pain hypersensitivity in green fluorescent protein (GFP)-positive bone marrow-chimeric mice subjected to a contusion SCI, and the mechanisms of such effects. BMSC transplantation at day 3 post-SCI improved motor function and relieved SCI-induced hypersensitivities to mechanical and thermal stimulation. The pain improvements were mediated by suppression of protein kinase C-γ and phosphocyclic AMP response element binding protein expression in dorsal horn neurons. BMSC transplants significantly reduced levels of p-p38 mitogen-activated protein kinase and extracellular signal-regulated kinase (p-ERK1/2) in both hematogenous macrophages and resident microglia and significantly reduced the infiltration of CD11b and GFP double-positive hematogenous macrophages without decreasing the CD11b-positive and GFP-negative activated spinal-microglia population. BMSC transplants prevented hematogenous macrophages recruitment by restoration of the blood-spinal cord barrier (BSCB), which was associated with decreased levels of (a) inflammatory cytokines (tumor necrosis factor-α, interleukin-6); (b) mediators of early secondary vascular pathogenesis (matrix metallopeptidase 9); (c) macrophage recruiting factors (CCL2, CCL5, and CXCL10), but increased levels of a microglial stimulating factor (granulocyte-macrophage colony-stimulating factor). These findings support the use of BMSC transplants for SCI treatment. Furthermore, they suggest that BMSC reduce neuropathic pain through a variety of related mechanisms that include neuronal sparing and restoration of the disturbed BSCB, mediated through modulation of the activity of spinal-resident microglia and the activity and recruitment of hematogenous macrophages.

Evaluation of low vision services on the quality of life of individuals with age-related macular degeneration

Background: Age-related macular degeneration (ARMD) is a major cause of irreversible visual loss in the elderly and a significant threat to their quality of life. Although low vision services often improve the functional outcomes of individuals with macular disease, it remains unclear whether or not they have any impact on quality of life. The principal aim of this study was to determine the effect of a hospital-based low vision clinic on the quality of life of individuals with ARMD. Methods: Forty patients with ARMD attended the low vision clinic at Milton Keynes University Hospital. Quality of life was measured with the vision-specific Low Vision Quality of Life (LVQOL) questionnaire and the general health EuroQol (EQ-5D-5L) questionnaire. Measures were completed at baseline (time zero, T0), and at three- (T3) and six-month (T6) follow-up visits. Results: The near visual acuity of individuals attending the low vision clinic for the first time improved significantly between visits T0 and T3 (p=0.005), reflecting the practiced use of their newly-dispensed low vision aids. As expected, there was no significant change in near acuity over this time period for existing patients. For both new and existing patients, a significant increase in LVQOL score was evident between visits T0 and T3, with a further significant improvement between T3 and T6. Similarly, there was a significant decrease in EQ-5D-5L questionnaire scores between visits T0 and T6. Conclusions: The higher LVQOL scores obtained at the end of the study period (T6) provide evidence that low vision services at Milton Keynes University Hospital served to improve patient quality of life. The reduction in EQ-5D-5L scores over the same time period suggests that low vision services also provide for an improvement in general health-related quality of life. Impact: The findings support the cause of low vision services to improve not only the vision and functional outcomes of individuals with macular disease but also their quality of life. Moreover, the findings suggest that a more efficient allocation of resources at low vision clinics may be possible through the standardisation of patient follow-up frequency.

Controllo ultra-low power di un modulatore back-scattering per applicazioni di localizzazione in sistemi RFID

In questa tesi viene elaborata un'applicazione ultra-low power (ULP) basata su microcontrollore, per implementare la procedura di controllo di diversi circuiti di un tag RFID. Il tag preso in considerazione è pensato per lavorare in assenza di batteria, da cui la necessita' di ridurre i consumi di potenza. La sua attivazione deve essere inoltre comandata attraverso un'architettura Wake up Radio (WuR), in cui un segnale di controllo radio indirizza e attiva il circuito. Nello specifico, la rete di decodifica dell'indirizzo è stata realizzata mediante il modulo di comunicazione seriale del microcontrollore. Nel Capitolo 1 verrà introdotto il tema dell'Energy Harvesting. Nel Capitolo 2 verrà illustrata l'architettura del sistema nel suo complesso. Nel Capitolo 3 verrà spiegato dettagliatamente il funzionamento del microcontrollore scelto. Il Capitolo 4 sarà dedicato al firmware implementato per svolgere le operazioni fondamentali imputate al micro per i compiti di controllo. Verrà inoltre introdotto il codice VHDL sviluppato per emulare l'output del modulo WuR mediante un FPGA della famiglia Cyclone II. Nel Capitolo 5 verrà presentata una stima dei consumi del microcontrollore in funzione dei parametri di configurazione del sistema. Verrà inoltre effettuato un confronto con un altro microcontrollore che in alcune condizioni potrebbe rappresentare iun'alternativa valida di progetto. Nei Capitoli 6 e 7 saranno descritti possibili sviluppi futuri e conclusioni del progetto. Le specifiche di progetto rilevanti della tesi sono: 1. minimo consumo energetico possibile del microcontrollore ULP 2. elevata rapidità di risposta per la ricezione dei tag, per garantire la ricezione di un numero maggiore possibile di indirizzi (almeno 20 letture al secondo), in un range di tempo limitato 3. generazione di un segnale PWM a 100KHz di frequenza di commutazione con duty cycle 50% su cui basare una modulazione in back-scattering.

Is alcohol consumption related to likelihood of reporting chronic widespread pain in people with stable consumption? : Results from UK Biobank

Acknowledgements This research has been conducted using the UK Biobank resource, and was funded by the University of Aberdeen. The authors have no conflicts of interest to declare.

PENTAZOCINE VERSUS PENTAZOCINE WITH RECTAL DICLOFENAC FOR POSTOPERATIVE PAIN RELIEF AFTER CESAREAN SECTION- A DOUBLE BLIND RANDOMIZED PLACEBO CONTROLLED TRIAL IN A LOW RESOURCE AREA.

BACKGROUND: The unimodal approach of using pentazocine as post-cesarean section pain relief is inadequate, hence the need for a safer, easily available and more effective multimodal approach. AIM: To evaluate the effectiveness of rectal diclofenac combined with intramuscular pentazocine for postoperative pain following cesarean section. METHODS: In this double blind clinical trial, 130 pregnant women scheduled for cesarean section under spinal anesthesia were randomly assigned to two groups. Group A received 100mg diclofenac suppository and group B received placebo suppository immediately following surgery, 12 and 24h later. Both groups also received intramuscular pentazocine 30mg immediately following surgery and 6 hourly postoperatively in the first 24 h. Postoperative pain was assessed by visual analogue scale at end of surgery and 2, 12 and 24 h after surgery. Patient satisfaction scores were also assessed. RESULTS: One hundred and sixteen patients completed the study. Combining diclofenac and pentazocine had statistically significant reduction in pain intensity at 2, 12, and 24 hours postoperatively compared to pentazocine alone (p <0.05). No significant side effects were noted in both groups. The combined group also had significantly better patient satisfaction scores. CONCLUSION: The addition of diclofenac suppository to intramuscular pentazocine provides better pain relief after cesarean section and increased patient satisfaction.

Travel, back and forth, to the myth. Cinema´s contribution to the formation of the tourist iconography of Mallorca

Mallorca, the largest of the Balearic Islands, is a well-known summer holidays destination; an ideal place to relax and enjoy the sun and the sea. That tourist gaze reflected on postcards results from advertising campaigns, where cinema played an important role with documentaries and fiction films. The origins of that iconography started in the decades of the 1920’s and 1930’s, reflecting the so-called myth of the “island of calm”. On the other hand, the films of the 1950’s and 1960’s created new stereotypes related to the mass tourism boom. Busy beaches and the white bodies of tourists replaced white sandy beaches, mountains and landscapes shown up in the movies of the early decades of the 20th century. Besides, hotels and nightclubs also replaced monuments, rural landscapes and folk exhibitions. These tourist images mirror the social and spatial transformations of Mallorca, under standardization processes like other seaside mass tourist destinations. The identity was rebuilt on the foundations of "modernity". Although "balearization" has not ceased, nowadays filmmaking about Mallorca is advertising again a stereotype close to that one of the 1920s and 1930s, glorifying the myth of the "island of calm". This singular identity makes the island more profitable for capital that searches socio-spatial differentiation in post-fordist times.