Anorectal malformations

Anorectal malformations comprise a wide spectrum of diseases, which can affect boys and girls, and involve the distal anus and rectum as well as the urinary and genital tracts. They occur in approximately 1 in 5000 live births. Defects range from the very minor and easily treated with an excellent functional prognosis, to those that are complex, difficult to manage, are often associated with other anomalies, and have a poor functional prognosis. The surgical approach to repairing these defects changed dramatically in 1980 with the introduction of the posterior sagittal approach, which allowed surgeons to view the anatomy of these defects clearly, to repair them under direct vision, and to learn about the complex anatomic arrangement of the junction of rectum and genitourinary tract. Better imaging techniques, and a better knowledge of the anatomy and physiology of the pelvic structures at birth have refined diagnosis and initial management, and the analysis of large series of patients allows better prediction of associated anomalies and functional prognosis. The main concerns for the surgeon in correcting these anomalies are bowel control, urinary control, and sexual function. With early diagnosis, management of associated anomalies and efficient meticulous surgical repair, patients have the best chance for a good functional outcome. Fecal and urinary incontinence can occur even with an excellent anatomic repair, due mainly to associated problems such as a poorly developed sacrum, deficient nerve supply, and spinal cord anomalies. For these patients, an effective bowel management program, including enema and dietary restrictions has been devised to improve their quality of life

Extremely long quasiparticle spin lifetimes in superconducting aluminium using MgO tunnel spin injectors

There has been an intense search in recent years for long-lived spin-polarized carriers for spintronic and quantum-computing devices. Here we report that spin polarized quasi-particles in superconducting aluminum layers have surprisingly long spin-lifetimes, nearly a million times longer than in their normal state. The lifetime is determined from the suppression of the aluminum's superconductivity resulting from the accumulation of spin polarized carriers in the aluminum layer using tunnel spin injectors. A Hanle effect, observed in the presence of small in-plane orthogonal fields, is shown to be quantitatively consistent with the presence of long-lived spin polarized quasi-particles. Our experiments show that the superconducting state can be significantly modified by small electric currents, much smaller than the critical current, which is potentially useful for devices involving superconducting qubits

Acute health effects after accidental exposure to styrene from drinking water in Spain

OBJECTIVES: We studied subjective health symptoms in a population accidentally exposed to high styrene concentrations in drinking tap water. The contamination occurred during the reparation of a water tank. METHODS: Residents of 27 apartments in two buildings using the contaminated water were contacted. A questionnaire on subjective symptoms was administered to 84 out of 93 persons living in the apartments at the time of the accident. Styrene concentration was measured in samples of water collected two days after the accident. The means of exposure associated with appearance of symptoms were examined through case-control analyses. RESULTS: Styrene in water reached concentrations up to 900 μg/L. Symptoms were reported by 46 persons (attack rate 55 %). The most frequent symptoms were irritation of the throat (26%), nose (19%), eyes (18%) and the skin (14%). General gastrointestinal symptoms were observed with 11% reporting abdominal pain and 7% diarrhea. The factors most strongly associated with symptoms were drinking tap water (OR = 7.8, 95% CI 1.3–48), exposure to vapors from the basement (OR = 10.4, 2.3–47) and eating foods prepared with tap water (OR = 8.6, 1.9–40). All residents in the ground floor reported symptoms. CONCLUSIONS: This accidental contamination led to very high styrene concentrations in water and was related to a high prevalence of subjective symptoms of the eyes, respiratory tract and skin. Similar exposures have been described in workers but not in subjects exposed at their residence. Various gastrointestinal symptoms were also observed in this population probably due to a local irritative effect

Colostomy closure: how to avoid complications

Purpose: Colostomy is an operation frequently performed in pediatric surgery. Despite its benefits, it can produce significant morbidity. In a previous publication we presented our experience with the errors and complications that occurred during cases of colostomy creation. We now have focused in the morbidity related to the colostomy closure. The technical details that might have contributed to the minimal morbidity we experienced are described. Methods: The medical records of 649 patients who underwent colostomy closure over a 28-year period were retrospectively reviewed looking for complications following these procedures. Our perioperative protocol for colostomy closure consisted in: clear fluids by mouth and repeated proximal stoma irrigations 24 h prior to the operation. Administration of IV antibiotics during anesthesia induction and continued for 48 h. Meticulous surgical technique that included: packing of the proximal stoma, plastic drape to immobilize the surgical field, careful hemostasis, emphasis in avoiding contamination, cleaning the edge of the stomas to allow a good 2-layer, end-to-end anastomosis with separated long-term absorbable sutures, generous irrigation of the peritoneal cavity and subsequent layers with saline solution, closure by layers to avoid dead space, and avoidance of hematomas. No drains and no nasogastric tubes were used. Oral fluids were started the day after surgery and patients were discharged 48-72 h after the operation. Results: The original diagnoses of the patients were: anorectal malformation (583), Hirschsprung\u27s disease (53), and others (13). 10 patients (1.5%) had complications: 6 had intestinal obstruction (5 due to small bowel adhesions, 1 had temporary delay of the function of the anastomosis due to a severe size discrepancy between proximal and distal stoma with a distal microcolon) and 4 incisional hernias. There were no anastomotic dehiscences or wound infection. There was no bleeding, no anastomotic stricture and no mortality. Conclusion: Based on this experience we believe that colostomy closure can be performed with minimal morbidity provided a meticulous technique is observed. © 2010 The Author(s)

Ethnicity and Cutaneous Melanoma in the City of Sao Paulo, Brazil: A Case-Control Study

Background: Over the last century the incidence of cutaneous melanoma has increased worldwide, a trend that has also been observed in Brazil. The identified risk factors for melanoma include the pattern of sun exposure, family history, and certain phenotypic features. In addition, the incidence of melanoma might be influenced by ethnicity. Like many countries, Brazil has high immigration rates and consequently a heterogenous population. However, Brazil is unique among such countries in that the ethnic heterogeneity of its population is primarily attributable to admixture. This study aimed to evaluate the contribution of European ethnicity to the risk of cutaneous melanoma in Brazil. Methodology/Principal Findings: We carried out a hospital-based case-control study in the metropolitan area of Sao Paulo, Brazil. We evaluated 424 hospitalized patients (202 melanoma patients and 222 control patients) regarding phenotypic features, sun exposure, and number of grandparents born in Europe. Through multivariate logistic regression analysis, we found the following variables to be independently associated with melanoma: grandparents born in Europe-Spain (OR = 3.01, 95% CI: 1.03-8.77), Italy (OR = 3.47, 95% CI: 1.41-8.57), a Germanic/Slavic country (OR = 3.06, 95% CI: 1.05-8.93), or >= 2 European countries (OR = 2.82, 95% CI: 1.06-7.47); eye color-light brown (OR = 1.99, 95% CI: 1.14-3.84) and green/blue (OR = 4.62; 95% CI 2.22-9.58); pigmented lesion removal (OR = 3.78; 95% CI: 2.21-6.49); no lifetime sunscreen use (OR = 3.08; 95% CI: 1.03-9.22); and lifetime severe sunburn (OR = 1.81; 95% CI: 1.03-3.19). Conclusions: Our results indicate that European ancestry is a risk factor for cutaneous melanoma. Such risk appears to be related not only to skin type, eye color, and tanning capacity but also to others specific characteristics of European populations introduced in the New World by European immigrants.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo - FAPESP [06-52041-9, 5-56069-2]Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)Conselho Nacional de Desenvolvimento Cientifico e Tecnologico - Brasil (National Counsel of Technological and Scientific Development - Brazil) - CNPq [478239/03-3]Conselho Nacional de Desenvolvimento Cientifico e Tecnologico Brasil (National Counsel of Technological and Scientific Development Brazil) CNP

Dynamical Boson Stars

The idea of stable, localized bundles of energy has strong appeal as a model for particles. In the 1950s John Wheeler envisioned such bundles as smooth configurations of electromagnetic energy that he called {\em geons}, but none were found. Instead, particle-like solutions were found in the late 1960s with the addition of a scalar field, and these were given the name {\em boson stars}. Since then, boson stars find use in a wide variety of models as sources of dark matter, as black hole mimickers, in simple models of binary systems, and as a tool in finding black holes in higher dimensions with only a single killing vector. We discuss important varieties of boson stars, their dynamic properties, and some of their uses, concentrating on recent efforts.Comment: 79 pages, 25 figures, invited review for Living Reviews in Relativity; major revision in 201

The effect of long-term homocysteine-lowering on carotid intima-media thickness and flow-mediated vasodilation in stroke patients: a randomized controlled trial and meta-analysis

<p>Abstract</p> <p>Background</p> <p>Experimental and epidemiological evidence suggests that homocysteine (tHcy) may be a causal risk factor for atherosclerosis. B-vitamin supplements reduce tHcy and improve endothelial function in short term trials, but the long-term effects of the treatment on vascular structure and function are unknown.</p> <p>Methods</p> <p>We conducted a sub-study of VITATOPS, a randomised, double-blind, placebo-controlled intervention trial designed to test the efficacy of long term B-vitamin supplementation (folic acid 2 mg, vitamin B₆25 mg and vitamin B₁₂0.5 mg) in the prevention of vascular events in patients with a history of stroke. We measured carotid intima-medial thickness (CIMT) and flow-mediated dilation (FMD) at least two years after randomisation in 162 VITATOPS participants. We also conducted a systematic review and meta-analysis of studies designed to test the effect of B-vitamin treatment on CIMT and FMD.</p> <p>Results</p> <p>After a mean treatment period of 3.9 ± 0.9 years, the vitamin-treated group had a significantly lower mean plasma homocysteine concentration than the placebo-treated group (7.9 μmol/L, 95% CI 7.5 to 8.4 versus 11.8 μmol/L, 95% CI 10.9 to 12.8, p < 0.001). Post-treatment CIMT (0.84 ± 0.17 mm vitamins versus 0.83 ± 0.18 mm placebo, p = 0.74) and FMD (median of 4.0%, IQR 0.9 to 7.2 vitamins versus 3.0%, IQR 0.6 to 6.6 placebo, p = 0.48) did not differ significantly between groups. A meta-analysis of published randomised data, including those from the current study, suggested that B-vitamin supplements should reduce CIMT (-0.10 mm, 95% CI -0.20 to -0.01 mm) and increase FMD (1.4%, 95% CI 0.7 to 2.1%). However, the improvement in endothelial function associated with homocysteine-lowering treatment was significant in short-term studies but not in longer trials.</p> <p>Conclusion</p> <p>Although short-term treatment with B-vitamins is associated with increased FMD, long-term homocysteine-lowering did not significantly improve FMD or CIMT in people with a history of stroke.</p> <p>Trial Registration</p> <p>Clinical Trial Registration URL: <url>http://www.actr.org.au/</url></p> <p>Trial Registration number: 12605000005651</p