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Increased oxidative stress, inflammation, and glutamate: Potential preventive and therapeutic targets for hearing disorders.
Hearing disorders constitute one of the major health concerns in the USA. Decades of basic and clinical studies have identified numerous ototoxic agents and investigated their modes of action on the inner ear, utilizing tissue culture as well as animal and human models. Current preventive and therapeutic approaches are considered unsatisfactory. Therefore, additional modalities should be developed. Many studies suggest that increased levels of oxidative stress, chronic inflammation, and glutamate play an important role in the initiation and progression of damage to the inner ear leading to hearing impairments. To prevent these cellular deficits, antioxidants, anti-inflammatory agents, and antagonists of glutamate receptor have been used individually or in combination with limited success. It is essential, therefore, to simultaneously enhance the levels of antioxidant enzymes by activating the Nrf2 (a nuclear transcriptional factor) pathway, dietary and endogenous antioxidant compounds, and B12-vitamins in order to reduce the levels of oxidative stress, chronic inflammation, and glutamate at the same time. This review presents evidence to show that increased levels of these cellular metabolites, biochemical or factors are involved in the pathogenesis of cochlea leading to hearing impairments. It presents scientific rationale for the use of a mixture of micronutrients that may decrease the levels of oxidative damage, chronic inflammation, and glutamate at the same time. The benefits for using oral administration of proposed micronutrient mixture in humans are presented. Animal and limited human studies indirectly suggest that orally administered micronutrients can accumulate in the inner ear. Therefore, this route of administration may be useful in prevention, and in combination with standard care, in improved management of hearing problems following exposure to well-recognized and studied ototoxic agents, such as noise, cisplatin, aminoglycoside antibiotics, and advanced age
Born on 19 November 1912: he, George Palade, a man who contributed so much to the progress of modern cell biology
In his 1971 paper George Palade wrote for Albert Claude, the founder of biological electron microscopic method: “Seldom has a field owed so much to a single man”. Herein, we articulate the same words for George Palade, the Teacher of many generations in cell biology research and education. Herein we focus on the paradigm shifts in the cell biology, namely the transition from light to transmission electron microscopy in studying cell protein secretion made by George Palade. Onward, we discuss on the transition from contractile to secretory phenotype of vascular smooth muscle cells initiated by Maria Daria Haust and developed by our research group. Taken together, we argue that one of the present challenges in cell biology is to cultivate secretocentric thinking and thus further focusing on how we could make secretory pathways work for the benefit of human’s health
Comparison of habitual visual acuity and stereoacuity between children attending KEMAS and urban private preschools
The assessment of a preschooler’s visual status is important as it forms part of the measure to assess the child’s school readiness. However, not all children attending preschools have equal opportunity to undergo vision screening programmes. In this study, we measured presenting habitual near and distance visual acuity and stereoacuity in 6-year-old children (n=385). These parameters were measured in and compared between preschoolers attending urban, privately-run kindergartens and those attending KEMAS preschools, which were typically from suburban and rural areas with families of very low income. Seven percent of KEMAS preschoolers failed the distance visual acuity test while the failure rate for private preschoolers was 6.0%. For near visual acuity, a higher percentage of private preschoolers failed the test (8.7%) than KEMAS preschoolers (4.9%). A slightly higher percentage of private preschoolers had weak stereopsis (3.3%) compared to KEMAS preschoolers (2.5%). However, the differences found between the two preschooler groups were not statistically significant (all p>0.05). The proportion of children who failed each of the screening criteria for distance vision, near vision, and stereopsis was similar between KEMAS and private preschools. Therefore, an universally inclusive vision screening programme should be conducted for all preschool types to detect, diagnose, treat, and potentially prevent any visual impairment
A deep learning approach for intelligent cockpits: learning drivers routines
Nowadays an increasing number of vehicles are being equipped with powerful cockpit systems capable of collecting drivers’ footprints over time. The collection of this valuable data opens effective opportunities for routine prediction. With the growing ability of vehicles to collect spatial and temporal information solving the routine prediction problem becomes crucial and feasible. It is then extremely important to advance and take advantage of the capabilities of these cockpit systems. A vehicle that is capable of predicting the next destination of the driver and when the driver intends to leave to that destination can prepare the journey in advance. Previous studies tackling the next location prediction problem have made use of Traditional Markov models, Neural Networks, Dynamic models, among others. In this work, a framework based on the hierarchical density-based clustering algorithm followed by a Long Short-Term Memory (LSTM) recurrent neural network is proposed for spatial-temporal prediction of drivers’ routines. Based on real-life driving scenarios of three different users, the proposed approach achieved a test set accuracy of 96.20%, 90.23%, and 86.40% when predicting the next destination and a R2 Score of 93.69, 79.21, and 28.81 when predicting the departure time, respectively. The results indicate that the proposed architecture can be implemented on the vehicle cockpit for the assistance of the management of future trips.Programme (COMPETE 2020) and national funds, through the ADI Project Bosch & UMinho “Easy Ride: Experience is everything” , ref POCI-01-0247 FEDER-039334FCT – Fundação para a Ciência e Tecnologia within the R&D Units Project Scope: UIDB/00319/2020 and UIDB/00013/2020
Port site herniation of the small bowel following laparoscopy-assisted distal gastrectomy: a case report
<p>Abstract</p> <p>Introduction</p> <p>Port-site herniation is a rare but potentially dangerous complication after laparoscopic surgery. Closure of port sites, especially those measuring 10 mm or more, has been recommended to avoid such an event.</p> <p>Case presentation</p> <p>We herein report the only case of a port site hernia among a series 52 consecutive cases of laparoscopy-assisted distal gastrectomy (LADG) carried out by our unit between July 2002 and March 2007. In this case the small bowel herniated and incarcerated through the port site on day 4 after LADG despite closure of the fascia. Initial manifestations experienced by the patient, possibly due to obstruction, and including mild abdominal pain and nausea, occurred on the third day postoperatively. The definitive diagnosis was made on day 4 based on symptoms related to leakage from the duodenal stump, which was considered to have developed after severe obstruction of the bowel. Re-operation for reduction of the incarcerated bowel and tube duodenostomy with peritoneal drainage were required to manage this complication.</p> <p>Conclusion</p> <p>We present this case report and review of literature to discuss further regarding methods of fascial closure after laparoscopic surgery.</p
A randomized study on migration of the Spectron EF and the Charnley flanged 40 cemented femoral components using radiostereometric analysis at 2 years
Background and purpose: We performed a randomized study to determine the migration patterns of the Spectron EF femoral stem and to compare them with those of the Charnley stem, which is regarded by many as the gold standard for comparison of implants due to its extensive documentation. Patients and methods: 150 patients with a mean age of 70 years were randomized, single-blinded, to receive either a cemented Charnley flanged 40 monoblock, stainless steel, vaquasheen surface femoral stem with a 22.2-mm head (n = 30) or a cemented Spectron EF modular, matte, straight, collared, cobalt-chrome femoral stem with a 28-mm femoral head and a roughened proximal third of the stem (n = 120). The patients were followed with repeated radiostereometric analysis for 2 years to assess migration. Results: At 2 years, stem retroversion was 2.3° and 0.7° (p < 0.001) and posterior translation was 0.44 mm and 0.17 mm (p = 0.002) for the Charnley group (n = 26) and the Spectron EF group (n = 74), respectively. Subsidence was 0.26 mm for the Charnley and 0.20 mm for the Spectron EF (p = 0.5). Interpretation: The Spectron EF femoral stem was more stable than the Charnley flanged 40 stem in our study when evaluated at 2 years. In a report from the Norwegian arthroplasty register, the Spectron EF stem had a higher revision rate due to aseptic loosening beyond 5 years than the Charnley. Initial stability is not invariably related to good long-term results. Our results emphasize the importance of prospective long-term follow-up of prosthetic implants in clinical trials and national registries and a stepwise introduction of implants
Statistical properties of microcracking in polyurethane foams under tensile test, influence of temperature and density
We report tensile failure experiments on polyurethane (PU) foams. Experiments
have been performed by imposing a constant strain rate. We work on
heterogeneous materials for whom the failure does not occur suddenly and can
develop as a multistep process through a succession of microcracks that end at
pores. The acoustic energy and the waiting times between acoustic events follow
power-law distributions. This remains true while the foam density is varied.
However, experiments at low temperatures (PU foams more brittle) have not
yielded power-laws for the waiting times. The cumulative acoustic energy has no
power law divergence at the proximity of the failure point which is
qualitatively in agreement with other experiments done at imposed strain. We
notice a plateau in cumulative acoustic energy that seems to occur when a
single crack starts to propagate
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