Self-report of headache in children and adolescents in Germany: possibilities and confines of questionnaire data for headache classification

The aim of this study was to estimate prevalence rates of different types of primary headache in 9- to 14-year-old children in a population-based sample. Case definition was based on International Classification of Headache Disorders (ICHD) criteria. The possibility of implementing these criteria within a questionnaire format, which has been regarded as problematic by some authors, was the main focus of the study. A questionnaire was sent to children and adolescents in 6400 randomly drawn families in southern Lower Saxony. Valid questionnaires were returned by 61.1% of the sample. The overall prevalence rate for tension-type headache (TTH) (criteria C and D) was 17.6% and for migraine (criteria B, C and D) 13.1%. Despite the use of abridged criteria for headache classification, 35.5% of all children reported headache that could not be classified using the ICHD criteria. The response behaviour of these children indicated that they had difficulties reporting symptoms that were defining for migraine or TTH. The classifiability of headache does not seem to be dependent on age or frequency of headache, but rather on the number of 'I don't know' answers given regarding headache characteristics. It is likely that studies reporting prevalence rates that are limited to migraine and or TTH diagnoses underestimate the true prevalence of headache in children and adolescents.

One-year course of paediatric headache in children and adolescents aged 8-15 years

The aims of the present study were the assessment of headache (HA) prevalence in German children and adolescents in the second year of a 4-year longitudinal study and the analysis of headache status change from year 1 to year 2. The original sample consisted of 8800 households with a child aged 7-14 years. A total of 4159 households responded in both year 1 and year 2, yielding 3984 valid parent questionnaires. Data regarding various aspects of the child's HA history and general health were gathered via mailed questionnaires from the parents. Of the households returning valid parent questionnaires at survey 2, 48.9% reported their child to have experienced headaches during the previous 6 months (53% at survey 1). Weekly HA was reported for 6.5% of the children, monthly or less frequent HA for 16.5% and 25.9%, respectively. With regard to headache diagnosis, 55.0% of the children and adolescents with HA experienced tension-type HA (TTH) and 11.3% migraine with or without aura (M). For more than half of the children and adolescents with HA (57.0%) the frequency of head pain remained stable over the period of 1 year (i.e. same frequency category in years 1 and 2). Improved and worsened HA status regarding frequency of occurrence was found in 22.3% and 20.7% of the subjects, respectively. Thus, there was no definite trend towards an increase of HA episodes over the course of 1 year regarding the individual child or adolescent. The most stable type of HA was TTH.

Localization and function of tissue macrophages

The rat monoclonal antibody F4/80 defines a plasma membrane glycoprotein of about 160 kilodaltons that is expressed by mature mouse macrophages. The antigen has been used to define macrophage distribution within the mouse (normal adult, embryo, infection models) by cytochemistry and quantitative immunochemical analysis. Macrophages migrate into fetal and adult haemopoietic and other tissues in an ordered sequence. The surface properties of 'fixed' macrophages isolated from various organs (bone marrow, liver, spleen) are distinct from those of circulating monocytes or free cells (peritoneal and pleural cavities, alveolar) and may play a role in local adhesion and trophic interactions with other cells.

Headache in German children and adolescents: a population-based epidemiological study

The aim of the present study was to assess the distribution and characteristics of headache in children aged 7-14 years in Lower Saxony (Germany). For the survey, 8800 households with children were randomly drawn from community registers. Parents received comprehensive questionnaires regarding various aspects of their child's headache history and general health by mail. The response rate was 63.5%. The 6-month prevalence of paediatric headache was 53.2% and increased with age (39% at 7 years to 63% at age 14). Overall, recurrent headache (> or =1/week) was experienced by 6.5% of the total sample and was significantly more common among older girls (> or =11 years) than their male counterparts. Boys and girls did not differ markedly from one another regarding headache occurrence and frequency until the age of 11. Mean age of headache onset was 7.5 years, with onset occurring at a significantly younger age among boys than among girls. In accordance with International Classification of Headache Disorders-II criteria, migraine was diagnosed in 7.5% and tension-type headache in 18.5% of the cases, hence a large proportion of the children had unclassifiable headache. Of the headache disorders, migraine was rated the most disabling, with the highest average intensity, highest frequency, duration of headache often exceeding 2 h and more frequent use of medication. In general, aura symptoms were rare except for visual disturbances (17%). Paediatric headache was strongly associated with other health problems, including other pain symptoms. Paediatric headache was also associated with a history of parental headache.

Neutralizing antibody responses in acute human immunodeficiency virus type 1 subtype C infection

The study of the evolution and specificities of neutralizing antibodies during the course of human immunodeficiency virus type 1 (HIV-1) infection may be important in the discovery of possible targets for vaccine design. In this study, we assessed the autologous and heterologous neutralization responses of 14 HIV-1 subtype C-infected individuals, using envelope clones obtained within the first 2 months postinfection. Our data show that potent but relatively strain-specific neutralizing antibodies develop within 3 to 12 months of HIV-1 infection. The magnitude of this response was associated with shorter V1-to-V5 envelope lengths and fewer glycosylation sites, particularly in the V1-V2 region. Anti-MPER antibodies were detected in 4 of 14 individuals within a year of infection, while antibodies to CD4-induced (CD4i) epitopes developed to high titers in 12 participants, in most cases before the development of autologous neutralizing antibodies. However, neither anti-MPER nor anti-CD4i antibody specificity conferred neutralization breadth. These data provide insights into the kinetics, potency, breadth, and epitope specificity of neutralizing antibody responses in acute HIV-1 subtype C infection.

Phenotypic characterization of HIV type 1 isolates from Ghana

Viral isolates from 27 HIV-1-infected patients in Ghana, most of whom were symptomatic, were characterized for coreceptor usage using MT-2 and U87.CD4 cells. Irrespective of clinical status, most infections were caused by CCR5-tropic viruses although three CXCR4-tropic viruses were also found. Genotyping was performed by sequencing the gp41 region. Seven viruses clustered with subtype G reference strains, while the remaining 20 viruses clustered within the subtype A reference viruses. Most subtype A isolates clustered loosely with the CRF02_AG viruses and are described as CRF02_AG-like. The V3 loop was sequenced in selected isolates including all isolates capable of using CXCR4. The V3 region of CXCR4-using viruses contained genetic traits characteristic of CXCR4-using subtype B and C viruses, such as increased charge, the presence of positively charged residues at positions 11 and 25, and loss of a predicted glycosylation site. This study supports previous work showing that CRF02_AG is responsible for most HIV-1 infections in Ghana at this time. The predominance of CCR5-using viruses, even in symptomatic patients, suggests that CCR5-blocking strategies may be useful for prevention and treatment of HIV-1 infections in Ghana.

Evidence suggests rigid aortic grafts increase systolic blood pressure: results of a preliminary study

Abdominal aortic aneurysm (AAA) is a serious complication of the aorta and is treated using vascular bypass grafts. Two main classes of graft are available to treat AAA; grafts implanted by open surgery and stent-grafts implanted using minimally invasive endovascular techniques. Both classes of graft consist of an aortic section which bifurcates into two iliac sections. It has been hypothesized that implantation of aortic grafts and stent-grafts serve to significantly increase abdominal aortic pressures. In this study, an open-loop computer-controlled pumping system was built to produce physiologically realistic pressure and flow-rates. Models of a compliant abdominal aortic aneurysm, a compliant walled graft and a tapered graft were manufactured using an injection moulding technique and fused deposition modelling was used to create a rigid walled graft. A specific transient flow-rate waveform was then applied at the inlet of each model and the resulting pressure waveforms 30 mm upstream from the bifurcation was recorded. Peak pressure measurements were recorded over the course of the pulse for each model. The compliant aneurysm model was found to have a systolic pressure of 107 mmHg while the complaint graft model was 153 mmHg. The rigid graft model had a peak systolic pressure of 199 mmHg. In the tapered graft, the peak pressure dropped to 142 mmHg. The data suggests that implanting a graft model in place of an aneurysm model in an in vitro flow circuit can increase the pressures recorded upstream from the iliac bifurcation and that tapered grafts may alleviate this problem.

Evidence of physiotherapeutic interventions for acute LBP patients

Objective: To identify the current evidence for acute low back pain (LBP) treatment techniques and to amalgamate this information into a clinically applicable algorithm for South African physiotherapists.Study design: Systematic review.Methods: Computerized bibliographical databases were systematically searched during September 2006 and October 2006 for primary and secondary research reporting on the efficacy of various physiotherapeutic treatment techniques for acute LBP. A search for clinical guidelines regarding acute LBP was also undertaken. Evidence levels were allocated to the primary and secondary research retrieved. Results: Twenty-one systematic reviews, four randomized controlled trials and eleven clinical guidelines were included in this review. There is Level 1 evidence that advice to stay active, McKenzie preferential exercises and spinal manipulative therapy (up to six weeks) is beneficial in the initial treatment of acute LBP. There is level 2 evidence that stability exercises, dry needling, heat wrap with exercises, cognitive behavioural therapy, printed patient education, massage (with education and exercises), and lifestyle modification might be potentially beneficial in the treatment of acute LBP. There is level 1 evidence that bed rest should not be recommended for simple acute LBP.  Should a patient not resolve in six weeks, red and yellow flags should be re-assessed, or patient should be referred to a specialist. Outcome: Based on the current evidence, a composite algorithm was developed to assist South African physiotherapists when making treatment decisions for acute LBP. Conclusion: There seems to be a lack of evidence for the efficacy of common treatment techniques used by physiotherapists in the management of acute LBP, indicating an urgent need for physiotherapy-specific, high-quality clinical trials. It is suggested that the evidence-based algorithm that has been developed, be used in the management of acute LBP to standardize physiotherapy intervention in South Africa.

Bayesian network analysis of resistance pathways against HIV-1 protease inhibitors

Interpretation of Human Immunodeficiency Virus 1 (HIV-1) genotypic drug resistance is still a major challenge in the follow-up of antiviral therapy in infected patients. Because of the high degree of HIV-1 natural variation, complex interactions and stochastic behaviour of evolution, the role of resistance mutations is in many cases not well understood. Using Bayesian network learning of HIV-1 sequence data from diverse subtypes (A, B, C, F and G), we could determine the specific role of many resistance mutations against the protease inhibitors (PIs) nelfinavir (NFV), indinavir (IDV), and saquinavir (SQV). Such networks visualize relationships between treatment, selection of resistance mutations and presence of polymorphisms in a graphical way. The analysis identified 30N, 88S, and 90M for nelfinavir, 90M for saquinavir, and 82A/T and 46I/L for indinavir as most probable major resistance mutations. Moreover we found striking similarities for the role of many mutations against all of these drugs. For example, for all three inhibitors, we found that the novel mutation 89I was minor and associated with mutations at positions 90 and 71. Bayesian network learning provides an autonomous method to gain insight in the role of resistance mutations and the influence of HIV-1 natural variation. We successfully applied the method to three protease inhibitors. The analysis shows differences with current knowledge especially concerning resistance development in several non-B subtypes.

Laparoscopic application of PGE2 to re-establish oviducal patency and fertility in infertile mares: a preliminary study

REASONS FOR PERFORMING STUDY

Mares are occasionally encountered that consistently fail to conceive when inseminated, naturally or artificially, with fertile stallion semen in the absence of any identifiable pathology of either the structure or function of their reproductive tract.

HYPOTHESIS

Temporary blockage of the oviducts by accumulations of naturally occurring oviducal masses may be preventing oviducal transport of the embryo to the uterus.

METHODS

Mares, with known reproductive histories, that had exhibited inexplicable failure of conception were treated by laparoscopically guided administration of PGE2-laced triacetin gel directly onto the surface of their oviducts.

RESULTS

Fifteen mares age 10-21 years that had exhibited inexplicable failure of conception during 1-4 years were treated, of which 14 (93%) conceived within the same or subsequent breeding season.

CONCLUSIONS

The high success rate of this treatment supports the tentative diagnosis of oviducal obstruction in these mares and indicates that blockage of the mare's oviducts may occur in the form of a moveable accumulation of debris rather than from permanent fibrous adhesions resulting from salpingitis.

POTENTIAL RELEVANCE

This laparoscopic application of PGE2 to the oviducts constitutes a sound and practical method of restoring fertility in mares suffering oviducal obstruction and further studies involving the procedure are warranted.

Blood Dendritic Cells Generated With Flt3 Ligand and CD40 Ligand Prime CD8+ T Cells Efficiently in Cancer Patients

Flt3 ligand mobilizes dendritic cells (DCs) into blood, allowing generation in vivo of large numbers of DCs for immunotherapy. These immature DCs can be rapidly activated by soluble CD40 ligand (CD40L). We developed a novel overnight method using these cytokines to produce DCs for cancer immunotherapy. Flt3 ligand-mobilized DCs (FLDCs) were isolated, activated with CD40L, loaded with antigenic peptides from influenza matrix protein, hepatitis B core antigen, NY-ESO-1, MAGE-A4, and MAGE-A10, and injected into patients with resected melanoma. Three injections were given at 4-week intervals. Study end points included antigen-specific immune responses (skin reactions to peptides alone or peptide-pulsed FLDCs; circulating T-cell responses), safety, and toxicity. No patient had a measurable tumor. Six patients were entered. FLDCs were obtained, enriched, and cultured under Good Manufacturing Practice grade conditions. Overnight culture with soluble CD40L caused marked up-regulation of activation markers (CD83 and HLA-DR). These FLDCs were functional and able to stimulate antigen-specific T cells in vitro. No significant adverse events were attributable to FLDCs. Peptide-pulsed FLDCs caused strong local skin reactions up to 60 mm diameter with intense perivascular infiltration of T cells, exceeding those seen in our previous peptide-based protocols. Antigen-specific blood T-cell responses were induced, including responses to an antigen for which the patients were naive (hepatitis B core antigen) and MAGE-A10. MAGE-A10-specific T cells with a skewed T-cell receptor repertoire were detected in 1 patient in blood ex vivo and from tumor biopsies. Vaccination with FLDCs pulsed with peptides is safe and primes immune responses to cancer antigens.

Persistence of nevirapine-resistant HIV-1 in women after single-dose nevirapine therapy for prevention of maternal-to-fetal HIV-1 transmission

Single-dose nevirapine (sdNVP) for prevention of mother-to-child transmission of HIV-1 can select nevirapine (NVP)-resistant variants, but the frequency, duration, and clinical significance of this resistance is not well defined. We used a sensitive allele-specific PCR assay to assess the emergence and persistence of NVP-resistant variants in plasma samples from 22 women with HIV-1 subtype C infection who participated in a study of sdNVP for prevention of mother-to-child transmission of HIV-1. The women were categorized into three groups on the basis of detection of NVP resistance by standard genotype analysis. Group 1 (n = 6) had NVP resistance detected at 2 and 6 mo after sdNVP, but not at 12 mo. Group 2 (n = 9) had NVP resistance detected at 2 mo, but not 6 mo. Group 3 (n = 7) had no NVP resistance detected at any time point. Allele-specific PCR analysis for the two most common NVP resistance mutations (K103N and Y181C) detected NVP-resistant variants in most (16 of 21) samples that were negative for NVP resistance by standard genotype, at levels ranging from 0.1% to 20% 1 yr after treatment. The frequency of NVP-resistant mutations decreased over time, but persisted above predose levels for more than 1 yr in > or = 23% of the women. These findings highlight the urgent need for studies assessing the impact of sdNVP on the efficacy of subsequent antiretroviral therapy containing NVP or other nonnucleoside reverse transcriptase inhibitors.

3-D numerical simulation of blood flow through models of the human aorta

A Spiral Computerized Tomography (CT) scan of the aorta were obtained from a single subject and three model variations were examined. Computational fluid dynamics modeling of all three models showed variations in the velocity contours along the aortic arch with differences in the boundary layer growth and recirculation regions. Further down-stream, all three models showed very similar velocity profiles during maximum velocity with differences occurring in the decelerating part of the pulse. Flow patterns obtained from transient 3-D computational fluid dynamics are influenced by different reconstruction methods and the pulsatility of the flow. Caution is required when analyzing models based on CT scans.

Injection-moulded models of major and minor arteries: the variability of model wall thickness owing to casting technique

Cardiovascular disease of major and minor arteries is a common cause of death in Western society. The wall mechanics and haemodynamics within the arteries are considered to be important factors in the disease formation process. This paper is concerned with the development of an efficient computer-integrated technique to manufacture idealized and realistic models of diseased major and minor arteries from radiological images and to address the issue of model wall thickness variability. Variations in wall thickness from the original computer models to the final castings are quantified using a CCD camera. The results found that wall thickness variation from the major and minor idealized artery models to design specification were insignificant, up to a maximum of 16 per cent. In realistic models, however, differences were up to 23 per cent in the major arterial models and 58 per cent in the minor arterial models, but the wall thickness variability remained within the limits of previously reported wall thickness results. It is concluded that the described injection moulding procedure yields idealized and realistic castings suitable for use in experimental investigations, with idealized models giving better agreement with design. Wall thickness is variable and should be assessed after the models are manufactured.

The process of decision-making by stressed social workers: to stay or leave the workplace

This paper considers the perception of stress and its impact on social workers, their relationships and decision-making. It begins with an exploration of stress, perception and how perception is utilized to understand stress experiences. It continues with exploration of decision-making processes. Finally it explores themes relating to decision-making based on case study findings of social workers who experienced stress and explores the outcomes of decision-making in relation to the workplace and how this might impact on retention.

Determination of the distribution of shallow-water seagrass and drift algae communities with acoustic seafloor discrimination

The spatial distribution of seagrass and algae communities can be difficult to determine in large, shallow lagoon systems where high turbidity prevents the use of optical methods like aerial photography or satellite imagery. Further complications can arise when algae are not permanently attached to the substratum and drift with tides and currents. A study using acoustic seafloor discrimination was conducted in the Indian River Lagoon (Florida, USA) to determine the extent of drift algae and seagrass. Acoustic surveys using the QTC View V system based on 50 and 200 kHz transducers were conducted near Sebastian Inlet. Results indicate that areas of seagrass can be identified, and are mixed with a high abundance of drift algae. Nearest-neighbor extrapolation was used to fill in spaces between survey lines and thus obtain spatially cohesive maps. These maps were then ground-truthed using data from towed video and compared using confusion matrices, The maps showed a high level of agreement (60%) with the actual distribution of algae, however some confusion existed between bare sand and algae as well as seagrass.

185 A NOVEL AND EFFECTIVE PROCEDURE FOR REMOVING HIV-1 AND HEPATITIS B AND C VIRUSES FROM SPIKED HUMAN SEMEN

The objectives of this study were to determine the effectiveness of a novel, trypsinized density gradient treatment designed to remove viruses from semen and to evaluate sperm viability after treatment. Exp. 1: Cryopreserved human semen (n = 6 donors) was layered on 2-mL columns of 45% Isolate (Irvine Scientific, Santa Ana, CA, USA) with or without 0.25% trypsin (trypsin-exposed and control, respectively), which overlaid 2-mL columns of 90% Isolate with or without 10 μg/mL soy-based trypsin inactivator (Sigma, St. Louis, MO, USA) and centrifuged (700g for 30 min). The layering of multiple density gradients is facilitated by a novel polypropylene tube insert, which also prevents contamination when extracting treated sperm (USA and international patents pending). Pellets were washed and then incubated at room temperature. Sperm were examined (motility and supravital staining) at 0, 2, 24, and 48 h post-treatment and the results evaluated using Wilcoxon Signed Rank and Rank Sum tests. Exp. 2: A cytopathic cell (MT-2) assay was conducted (6 replicates) to determine the effect of trypsin (1-min exposure) on HIV-1 RNA infectivity. Viral replication was assessed by syncytium formation and p24 antigen production. Exp. 3: Two pools of fresh human semen (N1 = 3 and N2 = 8 donors) were inoculated (1:1) with 1 × 108 copies/mL of cultured HIV-1 RNA, and one pool (N2) was inoculated (1:1) with plasma collected from patients infected with either Hepatitis B DNA (HBV) or C (HCV) RNA viruses; spiked and non-spiked aliquots were processed as in Exp. 1. Treated sperm pellets were analyzed for HIV-1 or HBV and HCV concentrations by the Bayer Versant branched DNA (bDNA; version 3.0) and/or the Roche Amplicor quantitative RT-PCR (1.5 ultrasensitive) assays at Toga Laboratories (Pty), Ltd. (Edenvale, South Africa). As a result of Exp. 1, there was significantly (P < 0.05) lower motility (but not supravital staining) between trypsin-treated and control sperm at 0 h (58.0 vs. 69.3%) and 2 h (54.7 vs. 62.9%) post-washing; however, no differences were noted after 24 h (P > 0.05). In Exp. 2, trypsin exposure affected HIV-1 RNA infectivity negatively as compared to controls in terms of MT-2 cell syncytium formation and p24 antigen production. Results of the bDNA and/or RT-PCR assays in Exp. 3 indicated that the procedure effectively reduced HIV-1, HBV, and HCV viral copies in the spiked semen samples to undetectable levels or levels below clinical relevance. In conclusion, the novel trypsin density gradient procedure was effective for removing HIV-1, HBV and HCV from spiked semen without markedly affecting sperm survival. Extrapolation of these results to natural infections may be unfounded for viruses (e.g. HBV) that are thought to integrate into sperm chromatin.

A mathematical model to predict the in vivo pulsatile drag forces acting on bifurcated stent grafts used in endovascular treatment of abdominal aortic aneurysms (AAA)

Endovascular treatment of abdominal aortic aneurysms (AAA) is a promising new alternative to the traditional surgical repair. However, the endovascular approach suffers problems such as stent graft migration, endoleaks and stent mechanism breakage. Fatigue failure is believed to be the major cause of stent graft migration and device breakage. Knowledge of the in vivo forces acting on such devices is a basic requirement for the design of a successful endovascular device. Using a Fourier series trigonometric fit of a typical pressure and flow relationship, a mathematical model, using the control volume method, was developed to predict the pulsatile drag forces acting on various bifurcated stent graft geometries. It was found that for an iliac angle of 30 degrees, a proximal diameter of 24 mm and an iliac diameter of 12 mm, the drag force varied, over the cardiac cycle, between 3.9 and 5.5 N in the axial direction. It was noted that for a specific iliac angle the drag force variation with proximal diameter approximates a quadratic fit, with an increase in proximal diameter producing an increase in drag force. The more compliant the aorta the higher the drag force. Previously published results demonstrated the axial loads (axial drag forces) required for stent graft migration for certain stents types are lower than the drag forces calculated in this study. It is believed that the results of this study can provide guidelines for the quantitative analyses of the in vivo drag forces experienced by stent grafts and could therefore be used as design criteria for such devices.