Impact of laser iridotomy on headache symptoms in angle-closure subjects

Graefe's Archive for Clinical and Experimental Ophthalmology - Migraine symptoms are frequently referred by glaucoma patients. Although most studies analyze headache in the acute setting of...     

A prospective study concerning the relationship between metal allergy and post-operative pain following total hip and knee arthroplasty

Purpose

A prospective study was conducted to detect whether a relationship exists between metal allergy and post-operative pain in total hip and knee arthroplasty patients. We postulated that to some extent a relationship does exist between them.

Materials and methods

Patients who had undergone total hip and knee arthroplasty surgery because of hip and knee disease were included. The exclusion criteria were patients who were treated with immunosuppressor two weeks pre-operatively, skin conditions around the patch testing site, and other uncontrollable factors. Each patient agreed to patch testing for three days before surgery. Photographic images before patch testing, two and three days after patch testing were obtained to evaluate the final incidence of metal allergy. The patch tests contained 12 metal elements; chromium, cobalt, nickel, molybdenum, titanium, aluminium, vanadium, iron, manganese, tin, zirconium, and copper. Two independent observers evaluated the images. The results were divided into a non-metal allergy group and a metal allergy group. Pre-operative and postoperative VAS score, lymphocyte transforming test, and X-rays were collected to detect the relationship between metal allergy and post-operative pain following total hip and knee arthroplasty.

Results

There were 96 patients who underwent pre-operative patch testing. The overall metal allergy rate was 51.1 % (49/96) in our study. Nickel, cobalt, manganese, and tin were the most common allergic metal elements in our study. Nine inappropriate cases were excluded, and 87 patients were finally included in our study. There were 36 metal allergy and 26 non-metal allergy patients in the THA group, while 11 metal allergy and 14 non-metal allergy patients were found in the TKA group. We found no relationship existed between metal allergy and post-surgery pain in total hip and knee arthroplasty.

Conclusion

Pain caused by metal allergy usually presents as persistent and recurrent pain. The white cell count, C-reactive protein, erythrocyte sedimentation rate and postoperative radiographs were not affected. Currently, patch testing and lymphocyte transforming tests are used for metal allergy diagnosis. We deemed that a relationship between post-surgery pain and metal allergy in total hip and knee patients may exist to some extent. Larger samples and longer follow-up time are essential for further study.     

Seniors Road Safety Enhancement through Perceptual-Motor Competences Training Program Impact upon the Performance on the Useful Field of Vision (UFOV)

The purpose of this study was to verify the efficacy of a Perceptual-Motor Competences Training Program upon the performance on UFOV of an experimental active group of elderly drivers. Program tasks were conceived to force subjects to divide their attention for central and peripheral stimuli, using a visual strategy of gazing at an anchor-point and, from there, detect important clues on peripheral visual field. For this purpose, almost all tasks were performed on groups of two, being one responsible for testing the other and switching functions from time to time (for instance, dropping one of two juggling handkerchiefs hold apart, one in each tester hand, with the partner having to detect which was dropped and react as quick as possible, catching it before it felt to the floor). We found a significant improvement in the capacity of dividing attention for central and peripheral stimuli under a visual environment full of distractors (selective attention UFOV test) following the Program, as well as a significant reduction on the category of risk (component based upon the three UFOV subtests results), which evidence very clearly the benefits of this training program on the elderly experimental group and its potential to reduce their risk of being involved in car accidents, on their fault, due to perceptual reasons.     

Impact of heterogeneity and socioeconomic factors on individual behavior in decentralized sharing ecosystems

Tens of millions of individuals around the world use decentralized content distribution systems, a fact of growing social, economic, and technological importance. These sharing systems are poorly understood because, unlike in other technosocial systems, it is difficult to gather large-scale data about user behavior. Here, we investigate user activity patterns and the socioeconomic factors that could explain the behavior. Our analysis reveals that (i) the ecosystem is heterogeneous at several levels: content types are heterogeneous, users specialize in a few content types, and countries are heterogeneous in user profiles; and (ii) there is a strong correlation between socioeconomic indicators of a country and users behavior. Our findings open a research area on the dynamics of decentralized sharing ecosystems and the socioeconomic factors affecting them, and may have implications for the design of algorithms and for policymaking.Every month, ∼150 million users worldwide share files over the Internet using BitTorrent (1), the most widely used decentralized peer-to-peer (P2P) communication protocol. Eleven years after its inception, file sharing through BitTorrent is one of the top three major contributors to the overall Internet traffic, accounting for 9–27% of the total traffic, depending on the continent (2, 3).The expansion in scale and breadth of decentralized file-sharing has highlighted the conflicts between the interests of creators (musicians and writers, e.g.) and those of P2P users. Creators and creative industries argue that they are being deprived of fair compensation for their work (4), which is being widely distributed for free in violation of copyright laws. Users, however, argue that P2P can be (and is) used for sharing nonproprietary contents, and warn that widespread monitoring of online activity by corporations and law enforcement violates P2P users’ right to privacy. Proof of the complexity of the situation includes the rejection of the Anti-Counterfeiting Trade Agreement by the European Parliament and the controversy with the Stop Online Piracy Act in the United States.Despite the growing social, economic, and technological importance of BitTorrent (4), there is currently little understanding of how users behave in this complex technosocial (5, 6) ecosystem. Due to the decentralized structure of P2P ecosystems, it is very difficult to gather large-scale data about interactions and behavioral patterns of the users without their explicit consent; this is in contrast to other forms of online exchange where all of the information is stored in a central system, be it publicly accessible as in Wikipedia (7), partially accessible through a public interface as in Twitter (8, 9) or Google [through its search logs (10) or its public services (11, 12)], or restricted as in Facebook (13, 14) or in email communications within organizations (15–18).Because of the difficulty to collect complete user-level data of large and representative samples of users (3), studies of user behavior in P2P networks have so far been based on (i) small datasets; (ii) aggregate data collected from “trackers” or from individual Internet service providers (ISPs); and (iii) incomplete user data collected using a single crawler client connected to the network (19–23).Here, we investigate the complete activity patterns of a large and representative pool of BitTorrent users. Our analysis reveals that P2P sharing is highly heterogeneous, that users are specialized, giving rise to well-defined user profiles, and that the abundance of certain user profiles in a country is highly correlated with socioeconomic factors. Our findings open a research area on the dynamics of decentralized sharing ecosystems, and may have implications for the understanding and design of algorithms and for policymaking.     

Pelvis width associated with bone mass distribution at the proximal femur in children 10–11 years old

Differences in skeletal geometry may generate different patterns of mechanical loading to bone. Impact and muscle loading during physical activity have been shown to influence skeletal geometry. The purpose of this study was to compare geometric measures of the pelvis and proximal femur (PF) of young children and to analyze the contribution and potential interaction of these geometric measures with physical activity on PF bone mass distribution. Participants were 149 girls and 145 boys, aged 10–11 years. Total body and left hip DXA scans were used to derive pelvic and PF geometric measures and PF bone mineral density (BMD) at the femoral neck (FN), trochanter (TR), and intertrochanter (IT). These subregions were used to represent bone mass distribution via three BMD ratios: FN:PF, TR:PF, and IT:PF. Physical activity was objectively measured using accelerometry, and maturity was estimated as the years of distance from peak height velocity. When compared to boys, girls had a wider pelvic diameter and greater interacetabular distances (p < 0.001), lower BMD at FN, TR, and IT (p < 0.05), and higher TR:PF (p < 0.001). After controlling for maturity, body height, and lean body mass, the interacetabular distance in girls explained 21.1 % (β = 0.713, p < 0.001) in TR:PF and 2.9 % (β = ?0.179, p = 0.031) in the IT:PF. Neck–shaft angle explained 5.6 % (β = ?0.265, p = 0.001) of the IT:PF and 3.1 % (β = 0.194, p = 0.018) of the FN:PF. In boys, FN axis length explained 2.9 % (β = 0.195, p = 0.040) of TR:PF. There was no main effect of physical activity or interaction effect with pelvic geometry in explaining BMD differences among the subregions of the PF. Even before sexual dimorphism, girls have a wider pelvis than boys, which accounted for proportionally greater BMD of the TR than other subregions of the PF.     

Endoscopic resection of submucosal tumors in muscularis propria: the choice between direct excavation and tunneling resection

Background

Endoscopic submucosal excavation (ESE) and submucosal tunneling endoscopic resection (STER) are nowadays both adopted by endoscopists to resect upper gastrointestinal submucosal tumors (SMTs) arising from muscularis propria. This study aimed to compare the efficacy and safety of these two techniques.

Methods

Seventy-seven patients were included in this retrospective study, among them, 35 received ESE and 42 received STER. Main outcome measurements included complete resection rate, perforation rate, adverse events, and tumor recurrence. Subgroup analysis based on tumor size was also performed.

Results

In general, ESE and STER had similar complete resection rate (94.7 vs. 97.7 %), perforation rate (10.5 vs. 13.3 %), and incidence of postoperative air leakage symptoms (13.2 vs. 2.2 %). No tumor recurrence occurred in any group. Subgroup analysis revealed that for tumors <10 mm, both techniques achieved satisfactory therapeutic effects (100 % complete resection, no adverse events); for tumors >10 mm, perforation rate increased in both ESE and STER (16 vs. 18.2 %), yet incidence of air leakage symptoms was significantly low in STER (3 %) compared to it in ESE (20 %).

Conclusions

For SMTs <10 mm, both ESE and STER have satisfactory therapeutic results, it is not necessary to pursue a difficult procedure when a simple method is available. For SMTs >10 mm, STER is a preferable choice in terms of preventing air leakage symptoms, especially, when perforation is likely to happen.