HBV/HIV co-infection: The dynamics of HBV in South African patients with AIDS

Objective. As sub-Saharan Africa is highly endemic for hepatitis Bvirus (HBV) and human immunodeficiency virus (HIV) infections,and their co-infection requires special management, we aimedto assess the serological and molecular characteristics of HBV inpatients with AIDS.Design. This was a cross-sectional, case control study, whichenrolled 200 patients with AIDS and 200 HIV-negative controls.HBV serology was done in all participants and HCV serologyin participants with a hepatitis B core antibody (anti-HBc) onlyserological pattern. Nested HBV polymerase chain reaction (PCR)and HBV viral load assays were used for HBV molecular detection.Results. Hepatitis B surface antigen (HBsAg) prevalence was3-fold higher while the ‘anti-HBc only’ pattern was 6-fold higher inthe AIDS group compared with the controls. Mean HBV viral loadwas significantly higher in HBsAg-positive patients with CD4+cell counts <100 cells/ìl than in patients with CD4+ cell counts of100-200 cells/ìl (p=0.019). There were markedly reduced hepatitisB surface antibody (anti-HBs) titres in the AIDS group comparedwith the controls (p=0.002). A significant proportion of AIDSpatients with an ‘anti-HBc only’ pattern had CD4+ cell counts <100cells/ìl (p=0.004). Occult HBV prevalence was 3.5% in the AIDSgroup compared with 1% in the controls (p=0.092). When occultHBV infection was taken into consideration, the overall HBVprevalence became 10% in the AIDS group and 3% in the controlgroup.Conclusion. We showed an increased HBV prevalence in patientswith AIDS and identified a CD4+ cell count <100 cells/ìl as amajor risk factor for the ‘anti-HBc only’ pattern and increasedHBV replication. These data have significant public healthimplications for HBV in developing countries, especially in areaswhere antiretroviral (ARV) guidelines do not cater for HBV/HIVco-infection

Reducing driving forces for pressed-in piles

Pile jacking techniques use static loading to install sheet piles with minimal environmental effects, such as noise and ground vibrations, which are often associated with other methods of driven piling. This paper describes a series of 20g centrifuge tests conducted to investigate two methods of reducing the large driving forces that can be associated with jacked sheet piles in stiff clay. In practice, pre-auguring at the clutch positions and water jetting techniques are routinely carried out prior to the installation of sheet piling in order to reduce the driving forces. However, these methods are known to contribute to ground movements and can detract from the advantages of jacked sheet piles. The tests involved driving model sheet piles, which were modified either by installing driving shoes to the base of the pile, or by ribbing the profile of the pile shaft. The driving forces of the modified piles were compared with those of a plain pile. The tests showed that the use of driving shoes and ribs can lead to the reduction of driving forces at greater depth

Multisensory information facilitates reaction speed by enlarging activity difference between superior colliculus hemispheres in rats

Animals can make faster behavioral responses to multisensory stimuli than to unisensory stimuli. The superior colliculus (SC), which receives multiple inputs from different sensory modalities, is considered to be involved in the initiation of motor responses. However, the mechanism by which multisensory information facilitates motor responses is not yet understood. Here, we demonstrate that multisensory information modulates competition among SC neurons to elicit faster responses. We conducted multiunit recordings from the SC of rats performing a two-alternative spatial discrimination task using auditory and/or visual stimuli. We found that a large population of SC neurons showed direction-selective activity before the onset of movement in response to the stimuli irrespective of stimulation modality. Trial-by-trial correlation analysis showed that the premovement activity of many SC neurons increased with faster reaction speed for the contraversive movement, whereas the premovement activity of another population of neurons decreased with faster reaction speed for the ipsiversive movement. When visual and auditory stimuli were presented simultaneously, the premovement activity of a population of neurons for the contraversive movement was enhanced, whereas the premovement activity of another population of neurons for the ipsiversive movement was depressed. Unilateral inactivation of SC using muscimol prolonged reaction times of contraversive movements, but it shortened those of ipsiversive movements. These findings suggest that the difference in activity between the SC hemispheres regulates the reaction speed of motor responses, and multisensory information enlarges the activity difference resulting in faster responses

Prevalence of traumatic psychological stress reactions in children and parents following paediatric surgery: a systematic review and meta-analysis

Background: Children undergoing surgery and their parents are at risk of developing post-traumatic stress reactions. We systematically reviewed the literature to understand the prevalence of this issue, as well as potential risk factors. Methods: We conducted a systematic review and meta-analysis, using PubMed, PsycInfo, Web of Science and Google Scholar, with searches conducted in February 2021. Papers were included if they measured post-traumatic stress in children and/or parents following paediatric surgery and were excluded if they did not use a validated measure of post-traumatic stress. Data were extracted from published reports. Findings: Our search yielded a total of 1672 papers, of which 16 met our inclusion criteria. In meta-analysis, pooled studies of children estimated an overall prevalence of 16% meeting criteria for post-traumatic stress disorder post surgery (N=187, 95% CI 5% to 31%, I2=80%). After pooling studies of parents, overall prevalence was estimated at 23% (N=1444, 95% CI 16% to 31%, I2=91%). Prevalence rates were higher than those reported in the general population. Risk factors reported within studies included length of stay, level of social support and parental mental health. Interpretation: There is consistent evidence of traumatic stress following surgery in childhood which warrants further investigation. Those delivering surgical care to children would benefit from a raised awareness of the potential for post-traumatic stress in their patients and their families, including offering screening and support

Cutaneous metastases of breast carcinoma: a case report

© 2009 Vano-Galvan et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

High-resolution computed tomography reconstructions of invertebrate burrow systems

The architecture of biogenic structures can be highly influential in determining species contributions to major soil and sediment processes, but detailed 3-D characterisations are rare and descriptors of form and complexity are lacking. Here we provide replicate high-resolution micro-focus computed tomography (μ-CT) data for the complete burrow systems of three co-occurring, but functionally contrasting, sediment-dwelling inter-tidal invertebrates assembled alone, and in combination, in representative model aquaria. These data (≤2,000 raw image slices aquarium−1, isotropic voxel resolution, 81 μm) provide reference models that can be used for the development of novel structural analysis routines that will be of value within the fields of ecology, pedology, geomorphology, palaeobiology, ichnology and mechanical engineering. We also envisage opportunity for those investigating transport networks, vascular systems, plant rooting systems, neuron connectivity patterns, or those developing image analysis or statistics related to pattern or shape recognition. The dataset will allow investigators to develop or test novel methodology and ideas without the need to generate a complete three-dimensional computation of exemplar architecture

Maximizing the impact of malaria funding through allocative efficiency: using the right interventions in the right locations.

BACKGROUND: The high burden of malaria and limited funding means there is a necessity to maximize the allocative efficiency of malaria control programmes. Quantitative tools are urgently needed to guide budget allocation decisions. METHODS: A geospatial epidemic model was coupled with costing data and an optimization algorithm to estimate the optimal allocation of budgeted and projected funds across all malaria intervention approaches. Interventions included long-lasting insecticide-treated nets (LLINs), indoor residual spraying (IRS), intermittent presumptive treatment during pregnancy (IPTp), seasonal mass chemoprevention in children (SMC), larval source management (LSM), mass drug administration (MDA), and behavioural change communication (BCC). The model was applied to six geopolitical regions of Nigeria in isolation and also the nation as a whole to minimize incidence and malaria-attributable mortality. RESULTS: Allocative efficiency gains could avert approximately 84,000 deaths or 15.7 million cases of malaria in Nigeria over 5 years. With an additional US$300 million available, approximately 134,000 deaths or 37.3 million cases of malaria could be prevented over 5 years. Priority funding should go to LLINs, IPTp and BCC programmes, and SMC should be expanded in seasonal areas. To minimize mortality, treatment expansion is critical and prioritized over some LLIN funding, while to minimize incidence, LLIN funding remained a priority. For areas with lower rainfall, LSM is prioritized over IRS but MDA is not recommended unless all other programmes are established. CONCLUSIONS: Substantial reductions in malaria morbidity and mortality can be made by optimal targeting of investments to the right malaria interventions in the right areas