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No standardized surveillance criteria exist for surgical site infection after breast tissue expander (BTE) access. This report provides a framework for defining postaccess BTE infections and identifies contributing factors to infection during the expansion period. Implementing infection prevention guidelines for BTE access may reduce postaccess BTE infections.
Diarrhoea remains a common cause of illness in Guatemala, with children suffering most frequently from the disease. This study directly compared the frequency, enterotoxin, and colonization factor (CF) profiles of enterotoxigenic Escherichia coli (ETEC) strains isolated from children living in a rural community in Guatemala and from Western visitors to the same location during the same seasons, using similar detection methodologies. We found that ETEC accounted for 26% of severe cases of diarrhoea in children requiring hospitalization, 15% of diarrhoea in the community, and 29% of travellers' diarrhoea in visitors staying ⩾2 weeks. The toxin and CF patterns of the ETEC strains isolated from both groups differed significantly (P < 0·0005) as determined by χ2 = 60·39 for CFs and χ2 = 35 for toxins, while ETEC phenotypes found in Guatemalan children were comparable to those found in children from other areas of the world.
Surveillance of newly acquired hepatitis C virus (HCV) infection is crucial for understanding the epidemiology of HCV and informing public health practice. However, monitoring such infections via surveillance systems is challenging because they are commonly asymptomatic. A literature review was conducted to identify methodologies used by HCV surveillance systems to identify newly acquired infections; relevant surveillance systems in 15 countries were identified. Surveillance systems used three main strategies to identify newly acquired infections: (1) asking physicians to classify cases; (2) identifying symptomatic cases or cases with elevated alanine aminotransferases; and (3) identifying cases with documented evidence of anti-HCV antibody seroconversion within a specific time-frame. Case-ascertainment methods varied with greater completeness of data in enhanced compared to passive surveillance systems. Automated systems that extract and link testing data from multiple laboratory and clinic databases may provide an opportunity for collecting testing histories for individuals that is less resource intensive than enhanced surveillance.
Multisomatoform disorder is characterised by severe and disabling bodily symptoms, and pain is one of the most common and impairing of these. Furthermore, these bodily symptoms cannot be explained by an underlying organic disorder. Patients with multisomatoform disorder are commonly found at all levels of healthcare and are typically difficult to treat for physicians as well as for mental health specialists.
To test whether brief psychodynamic interpersonal therapy (PIT) effectively improves the physical quality of life in patients who have had multisomatoform disorder for at least 2 years.
We recruited 211 patients (from six German academic out-patient centres) who met the criteria for multisomatoform disorder for a randomised, controlled, 12-week, parallel-group trial from 1 July 2006 to 1 January 2009 (International Standard Randomised Controlled Trial Number ISRCTN23215121). We randomly assigned the patients to receive either 12 weekly sessions of PIT (n = 107) or three sessions of enhanced medical care (EMC, n = 104). The physical component summary of the Short Form Health Survey (SF-36) was the pre-specified primary outcome at a 9-month follow-up.
Psychodynamic interpersonal therapy improved patients' physical quality of life at follow-up better than EMC (mean improvement in SF-36 score: PIT 5.3, EMC 2.2), with a small to medium between-group effect size (d = 0.42, 95% CI 0.15–0.69, P = 0.001). We also observed a significant improvement in somatisation but not in depression, health anxiety or healthcare utilisation.
This trial documents the long-term efficacy of brief PIT for improving the physical quality of life in patients with multiple, difficult-to-treat, medically unexplained symptoms.
Silent sinus syndrome is characterised by spontaneous enophthalmos and hypoglobus, in association with chronic atelectasis of the maxillary sinus, and in the absence of signs or symptoms of intrinsic sinonasal inflammatory disease. Traditionally, correction of the enophthalmos involved reconstruction of the orbital floor, which was performed simultaneously with sinus surgery. Recently, there has been increasing evidence to support the performance of uncinectomy and antrostomy alone, then orbital floor reconstruction as a second-stage procedure if needed.
We performed a retrospective review of 23 cases of chronic maxillary atelectasis managed in our unit with endoscopic uncinectomy and antrostomy alone. All patients were operated upon by the same surgeon.
Twenty-two of the 23 patients had either complete or partial resolution. One patient had ongoing enophthalmos, and was considered for an orbital floor reconstruction as a second-stage procedure.
Our case series demonstrates that dynamic changes in orbital floor position can occur after sinus re-ventilation. These findings support the approach of delaying orbital floor reconstruction in cases of silent sinus syndrome treated with sinus re-ventilation, as such reconstruction may prove unnecessary over time.
We analysed the data from the control group in a typhoid vaccine trial in Karachi to assess the differences in individual-, household- and cluster-level characteristics for developing typhoid fever. The annual incidence of typhoid in children aged 2–16 years in the control arm of the vaccine trial was 151/100 000 population. After adjustment, the risk of typhoid was lower with increasing age [risk ratio (RR) 0·89, 95% confidence interval (CI) 0·83–0·95], was higher with an increase in population density (RR 1·13, 95% CI 1·05–1·21) and was lower in the households using a safe drinking-water source (RR 0·63, 95% CI 0·41–0·99). Typhoid fever affects younger children living in areas of high population density and lack of access to safe water in Pakistan. A combination of environmental and biological interventions is required to prevent the continued epidemiological and economic impact of typhoid fever in high-risk areas of Pakistan.
The earthquake in January 2010 killed more than 250,000 Haitians and caused traumatic injury to tens of thousands of survivors. In the aftermath of the earthquake, Haitian civilians assisted in various medical roles. Many of the civilians requested training, and 8 months after the earthquake, a team of American clinicians, EMTs and health educators returned to Haiti to teach a course in basic lifesaving and emergency care.
Using a modified French-language EMS training curriculum, 60 community members with no previous medical experience were trained during an intense 2-month period. Trainings were held to teach basic lifesaving and stabilization skills. The Gwoup Ayisyen pou Ijans was formed and is preparing to take the French-language EMS exam. A follow-up study is being conducted to assess the capabilities of the students.
Preliminary challenges included securing safe places for training and teaching in both French and Kreyol. Successes were the willingness of trainers to volunteer time and equipment, and the high motivation of the students, despite the inability of the government to promise consistent work for an EMT force.
Single-phase KNbO3 was prepared using bimetallic alkoxides. Potassium-niobium ethoxide, KNb(OC2H5)6, and potassium-niobium propoxide, KNb(OC3H7)6, were synthesized and subsequently hydrolyzed using several water concentrations. Potassium-deficient particles were rapidly precipitated when higher water concentrations were used and this resulted in the formation of a multiphase material after calcination. In contrast, single-phase KNbO3 powders could be prepared by two methods: (1) hydrolysis of KNb(OC3H7)6/propanol solutions using 1 mole water (per mole of propoxide) added as a water/propanol solution and (2) hydrolysis of KNb(OC2H5)6,/ethanol solutions using 1 mole of water (per mole of ethoxide) added as a water/methanol solution. The latter method was also used to form thin films of KNbO3.
Laser-assisted etching techniques have been developed for alloyselective patterning of GaAs/AlGaAs layered structures. Such techniques are potentially very important for the fabrication of a large variety of heterostructure devices. Studies have been carried out with several liquid etchants and have utilized a CW dye laser tuned to a wavelength above the band edge of GaAs, but below that of the AlGaAs layer (e.g., λ = 0.85 μm) to etch GaAs. Using the laser focal spot to spatially define the etched area, features exhibiting very smooth interface surfaces were produced in MBE-grown epitaxial layers. A high degree of selectivity for GaAs over A1(0.4)Ga(0.6)As, low background etch rates, and high feature etch rates (> 2 μm/min) were demonstrated. Patterned etching with AZ 1350J photoresist exhibited good pattern resolution and nearly vertical sidewall profiles. Etchant mixtures of dilute H2S04:H202:H20 and HNO3:H20 produced qualitatively different results, with the HNO3:H20 mixture exhibiting a tendency to leave a residual GaAs layer at the interface, even for long etch times. Surface analysis techniques, including Auger spectroscopy, profilometry, and interference contrast microscopy have been used to characterize the etched structures, and a simplified analytical model has been used to predict the qualitative dependence of etch rate on layer thickness.
Continuous silicon carbide fibers (”UF fibers”) with low oxygen content (∼2 wt%) were prepared by dry spinning of high molecular weight polycarbosilane solutions and subsequent pyrolysis of the polymer fibers. Room temperature mechanical properties were similar to those of commercially-available Nicalon™ fibers, as average tensile strengths as high as 3 GPa were obtained for some batches with fiber diameters in the range ∼10–15 μm Furthermore, UF fibers showed significantly better thermomechanical stability compared to Nicalon™, as indicated by lower weight losses, lower specific surface areas, and improved strength retention after heat treatment at temperatures up to 1700°C. UF fibers were also characterized by elemental analysis, X-ray diffraction, and scanning Auger microprobe. Strategies were suggested for achieving further improvements in thermomechanical stability.
Thin film of GaAs/AlGaAs multiple quantum well (MQW) structure have been bonded to the lithium tantalate (LiTaO3) or calcium carbonate (CaCO3) substrates cut such that one of the linear thermal expansion coefficients almost matches that of the MQW while its orthogonal counterpart does not. By choosing the proper bonding and operating temperatures, in-plane anisotropic strain up to 0.3% has been achieved. The transmission spectrum shows an anisotropy in excitonic absorption which results in a polarization rotation of a light beam at normal incidence to the structure. The theoretical calculation is in agreement with the experimental results. Using the polarization rotation, we have demonstrated a novel MQW light modulator with an exceedingly high contrast ratio of 330:1.
Young's modulus, tensile strength and the storage shear modulus experiments were performed on silica-filled ethylene-vinyl acetate composites and the results were correlated with polymer-filler interaction energy. The polymer-filler interaction energy was determined by wetting and infrared spectroscopy experiments. The interaction energy was characterized by the work of adhesion. The results indicate there is a strong correlation between modulus and tensile strength and the work of adhesion. There was an exponential relationship of modulus and tensile strength with the reciprocal of the work of adhesion.
We are investigating the transmission of low energy ions (<10 eV) through ultrathin films of condensed rare gases. Our goal is to address the issue of the depth of origin of secondary ions that desorb from solid surfaces under the impact of ionizing radiation, such as electrons, photons, or through ion sputtering. The secondary ions are produced by electron stimulated desorption (ESD) from a suitable substrate, such as an oxide or an adsórbate on a metal single crystal; the overlayer gas is condensed onto this substrate. The yield, energy and angular distributions of the ions are measured as a function of overlayer thickness. We find that 7 eV oxygen ions can be transmitted through rare gas films (Kr, Xe) several ML thick. In contrast, O+ is completely suppressed by 0.5 ML of H2O. Surprisingly, we find the F− yield to be 4 times higher in the presence of 1 ML of Xe, compared to the clean surface value, accompanied by a dramatic change in the ions’ angular distribution. We discuss a model which considers elastic scattering and charge transfer of the ions with rare gas atoms, as well as the structure of the surface and the electronic properties of the solid-vacuum interface.
During epidemics of cholera in two rural sites (Bakerganj and Mathbaria), a much higher proportion of patients came for treatment with severe dehydration than was seen in previous years. V. cholerae O1 isolated from these patients was found to be El Tor in its phenotype, but its cholera toxin (CT) was determined to be that of classical biotype. Whether the observed higher proportion of severe dehydration produced by the El Tor biotype was due to a shift from El Tor to classical CT or due to other factors is not clear. However, if cholera due to strains with increased severity spread to other areas where treatment facilities are limited, there are likely to be many more cholera deaths.
Attempts to explain the clear seasonality of rotavirus infections have been made by relating disease incidence to climate factors; however, few studies have disentangled the effects of weather from other factors that might cause seasonality. We investigated the relationships between hospital visits for rotavirus diarrhoea and temperature, humidity and river level, in Dhaka, Bangladesh, using time-series analysis adjusting for other confounding seasonal factors. There was strong evidence for an increase in rotavirus diarrhoea at high temperatures, by 40·2% for each 1°C increase above a threshold (29°C). Relative humidity had a linear inverse relationship with the number of cases of rotavirus diarrhoea. River level, above a threshold (4·8 m), was associated with an increase in cases of rotavirus diarrhoea, by 5·5% per 10-cm river-level rise. Our findings provide evidence that factors associated with high temperature, low humidity and high river-level increase the incidence of rotavirus diarrhoea in Dhaka.
To determine if a prediction of epidemic cholera using climate data can be made, we performed autoregression analysis using the data recorded in Dhaka City, Bangladesh over a 20-year period (1983–2002) comparing the number of children aged <10 years who were infected with Vibrio cholerae O1 to the maximum and minimum temperatures and rainfall. We formulated a simple autoregression model that predicts the monthly number of patients using earlier climate variables. The monthly number of patients predicted by this model agreed well with the actual monthly number of patients where the Pearson's correlation coefficient was 0·95. Arbitrarily defined, 39·4% of the predicted numbers during the study period were within 0·8–1·2 times the observed numbers. This prediction model uses the climate data recorded 2–4 months before. Therefore, our approach may be a good basis for establishing a practical early warning system for epidemic cholera.
A total of 113 strains of Shigella dysenteriae type 2 isolated from patients attending the Dhaka diarrhoea treatment centre of ICDDR,B: Centre for Health and Population Research during the period 1999–2004 were studied. Serotype of the isolates was confirmed using commercially available antisera. Except for arabinose fermentation, all the strains had similar biochemical reactions. More than 60% of the strains were sensitive to commonly used antibiotics; only 6% (n=7) of the strains were resistant to nalidixic acid, and none of the strains were resistant to mecillinam and ciprofloxacin. All strains were invasive as demonstrated by the presence of a 140 MDa plasmid, ial, sen and ipaH genes, Congo Red absorption ability and by the Sereny test performed on representative strains. Plasmid patterns were heterogeneous but more than 50% of strains were confined to a single pattern. All strains possessed a 1·6 MDa plasmid and 87% of the strains contained a 4 MDa plasmid. Middle-range plasmids (90 MDa to 30 MDa) present in 36% of the strains were not associated with antibiotic resistance. All the strains were clustered within a single type with four subtypes by pulsed-field gel electrophoresis while ribotyping patterns of all the strains were identical.