Cryptosporidium oocysts in Ghanaian AIDS patients with diarrhoea

Background: Although Cryptosporidium spp. infections in acquired immunodeficiency syndrome patients (AIDS) with chronic diarrhoea have been reported in several African countries, there is no information regarding cryptosporidial diarrhoea in Ghanaian AIDS patients. Objective: To investigate the occurrence of C. parvum and other gastrointestinal parasitic agents in Ghanaian AIDS patients with chronic diarrhoea. Design: Prospective study of HIV/AIDS patients with diarrhoea over a nine month period. Setting: Korle-Bu Teaching Hospital and Korle-Bu Polyclinic Accra, Ghana. Results: Analysis of stool specimens from clinically diagnosed HIV/AIDS (n=2I; mean CD4 count was 288 cells per microliter, 95% confidence interval of 237 to 340 cells per microliter) and HIV-seronegative (n=27) patients revealed C. parvum in six (28.6%) of HIV/AIDS and 10 (37.0%) of the HIV-seronegative patients, respectively. Three other HIV/AIDS cases had other infections involving Strongyloides stercoralis 4.8% (l/21) and Salmonella spp. 9.5% (2/21). There was no concomitant association between C. parvum and any other parasites found. Also, no enterobacteria was found in the HIV-seronegative patients. Conclusion: This study demonstrates the prevalence of Cryptosporidium sp. in both HIV/ AIDS and HIV-seronegative individuals in Ghana. However, there was no statistical association between cryptosporidiosis and HIV/AIDS (p>0.05). East African Medical Journal Vol.80(7) 2003: 369-37

On the Stability and Structural Dynamics of Metal Nanowires

This article presents a brief review of the nanoscale free-electron model, which provides a continuum description of metal nanostructures. It is argued that surface and quantum-size effects are the two dominant factors in the energetics of metal nanowires, and that much of the phenomenology of nanowire stability and structural dynamics can be understood based on the interplay of these two competing factors. A linear stability analysis reveals that metal nanocylinders with certain magic conductance values G=1, 3, 6, 12, 17, 23, 34, 42, 51, 67, 78, 96, ... times the conductance quantum are exceptionally stable. A nonlinear dynamical simulation of nanowire structural evolution reveals a universal equilibrium shape consisting of a magic cylinder suspended between unduloidal contacts. The lifetimes of these metastable structures are also computed.Comment: 8 pages, 6 figure

Universal Vectorial and Ultrasensitive Nanomechanical Force Field Sensor

Miniaturization of force probes into nanomechanical oscillators enables ultrasensitive investigations of forces on dimensions smaller than their characteristic length scale. Meanwhile it also unravels the force field vectorial character and how its topology impacts the measurement. Here we expose an ultrasensitive method to image 2D vectorial force fields by optomechanically following the bidimensional Brownian motion of a singly clamped nanowire. This novel approach relies on angular and spectral tomography of its quasi frequency-degenerated transverse mechanical polarizations: immersing the nanoresonator in a vectorial force field does not only shift its eigenfrequencies but also rotate eigenmodes orientation as a nano-compass. This universal method is employed to map a tunable electrostatic force field whose spatial gradients can even take precedence over the intrinsic nanowire properties. Enabling vectorial force fields imaging with demonstrated sensitivities of attonewton variations over the nanoprobe Brownian trajectory will have strong impact on scientific exploration at the nanoscale

Erratum to “Gastroenteropancreatic Neuroendocrine Neoplasia Characterization in Portugal: Results from the NETs Study Group of the Portuguese Society of Endocrinology, Diabetes and Metabolism”

In the article titled "Gastroenteropancreatic Neuroendocrine Neoplasia Characterization in Portugal: Results from the NETs Study Group of the Portuguese Society of Endocrinology, Diabetes and Metabolism"[1], the affiliation for I. Claro was labeled incorrectly. The correct affiliation of the author I. Claro is Instituto Portugûes de Oncologia de Lisboa, Francisco Gentil (IPOLFG), 1099-023 Lisboa, Portugal

Mammographic over-screening: Evaluation based on probabilistic linkage of records databases from the breast cancer information system (SISMAMA)

The Brazilian Ministry of Health recommends biennial mammographic screening for women aged between 50 and 69 years. Since screening is opportunistic in the country, the actual periodicity varies. This study sought to test a methodology for estimating over-screening due to excessive periodicity, defined as a smaller than recommended interval between exams, and its association with socio-demographic characteristics. A cohort of women who underwent mammography in 2010, and whose result was normal, was assembled through probabilistic linkage SISMAMA records based on a set of personal identifiers. We used data from women living in the micro health region of Juiz de Fora/Lima Duarte/Bom Jardim, Minas Gerais State, Brazil, who were followed in the System until the end of 2012. The rate of over-screening was 150/1,000 women/year (95%CI: 144.9-155.9), affecting 21% of women. Over-screening increased by 24% during Pink October campaigns (adjusted HR = 1.24; 95%CI: 1.15-1.35). The shorter the time passed since the last mammogram, the greater the odds of over-screening. Compared with women who had never had a mammogram prior to 2010, women who had had one in the previous 2 years were two times more likely to be over-screened (adjusted HR = 2.01; 95%CI: 1.74-2.31) whilst those who had had a mammogram ≤ 1 year previously were three times more likely to be over-screened (adjusted HR = 3.27; 95%CI: 2.87-3.73). Over-screening was substantial in this population, excessively exposing women to the risks of screening with no additional benefits and overestimating mammogram coverage. The methodology proved to be successful and should be applied to representative populations in order to guide breast cancer control policies