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Selected AbstractsHuman gastrointestinal nematode infections: are new control methods required?INTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 5 2006Gillian Stepek Summary Gastrointestinal (GI) nematode infections affect 50% of the human population worldwide, and cause great morbidity as well as hundreds of thousands of deaths. Despite modern medical practices, the proportion of the population infected with GI nematodes is not falling. This is due to a number of factors, the most important being the lack of good healthcare, sanitation and health education in many developing countries. A relatively new problem is the development of resistance to the small number of drugs available to treat GI nematode infections. Here we review the most important parasitic GI nematodes and the methods available to control them. In addition, we discuss the current status of new anthelmintic treatments, particularly the plant cysteine proteinases from various sources of latex-bearing plants and fruits. [source] Osteoporosis and the Global Competition for Health Care Resources,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 7 2004L Joseph Melton III Abstract Global aging superimposed on existing infectious diseases and trauma will aggravate competition for health care resources to diagnose and treat osteoporosis. Efforts to implement public health measures are needed, but the targeted approach to assessment and treatment of high-risk individuals must also be refined. Increases in the elderly population worldwide will cause a dramatic rise in osteoporotic fractures, but other age-related diseases will increase as well. Changes will be superimposed on existing public health problems (e.g., malaria, alcoholism), and these acute health care needs will take priority in some areas. Societies in most parts of the world may have to limit osteoporosis control to broad public health measures, and such efforts (e.g., calcium and vitamin D supplementation) should be supported. In these regions, clinical decision-making will generally be limited to treating patients with fractures (who presumably have already failed any public health measures in place), or in a few wealthy countries, to patients with low bone density identified by case-finding. Case-finding approaches will vary with the resources available, although unselective (mass) screening by bone densitometry is largely ineffective and unaffordable anywhere. The key to clinical decision-making on behalf of individuals will be an assessment of absolute fracture risk, and the tools needed to predict the risk of an osteoporotic fracture over the next 10 years are now being developed. These include bone density measures, but also incorporate other risk factors (e.g., fracture history, corticosteroid use), which may allow extension of fracture risk prediction to nonwhite populations and to men. Even with a universal risk prediction tool, cost-effective treatment thresholds will vary by country based on the level of fracture risk in the region and on the resources available for health care. To better compete for these resources, efforts should be made to lower the cost of osteoporosis interventions. Additionally, evidence is needed that these interventions are really effective in reducing fractures in the community. [source] Review article: omega-3 fatty acids , a promising novel therapy for non-alcoholic fatty liver diseaseALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 7 2010G. S. MASTERTON Aliment Pharmacol Ther,31, 679,692 Summary Background, Non-alcoholic fatty liver disease affects 10,35% of the adult population worldwide; there is no consensus on its treatment. Omega-3 fatty acids have proven benefits for hyperlipidaemia and cardiovascular disease, and have recently been suggested as a treatment for non-alcoholic fatty liver disease. Aims, To review the evidence base for omega-3 fatty acids in non-alcoholic fatty liver disease and critically appraise the literature relating to human trials. Methods, A Medline and PubMed search was performed to identify relevant literature using search terms ,omega-3', ,N-3 PUFA', ,eicosapentaenoic acid', ,docosahexaenoic acid', ,non-alcoholic fatty liver disease' and ,NAFLD'. Results, Omega-3 fatty acids are important regulators of hepatic gene transcription. Animal studies demonstrate that they reduce hepatic steatosis, improve insulin sensitivity and reduce markers of inflammation. Clinical trials in human subjects generally confirm these findings, but have significant design inadequacies. Conclusions, Omega-3 fatty acids are a promising treatment for non-alcoholic fatty liver disease which require to be tested in randomized placebo-controlled trials. [source] Worldwide trends in bilateral cochlear implantation,THE LARYNGOSCOPE, Issue S2 2010B. Robert Peters MD Abstract Objectives/Hypothesis: The goal of this study is to ascertain worldwide experience with bilateral cochlear implantation (BCI) with regard to patient demographics, trends in provision of BCI to adult and child patient populations, differences and similarities in BCI candidacy criteria, diagnostic requirements, and treatment approaches among clinicians in high-volume cochlear implant centers. Study Design: Retrospective/prospective. Methods: An electronic survey consisting of 59 mainly multiple-choice questions was developed for online completion. It examined the implant experience and clinical opinion of expert cochlear implant (CI) centers worldwide on the indications, motivations, and contraindications for adult and pediatric, simultaneous and sequential BCI candidacy. Centers were chosen to complete the survey based on their known reputation as a center of excellence. Patient demographics were queried for two time periods to elucidate trends: 2006 and prior, and for the year 2007. Results: Seventy-one percent (25/35) of the CI clinics approached completed the survey. Collectively, these 25 clinics represent experience with approximately 23,200 CI users globally, representing 15% of the total estimated CI population worldwide. The total number of BCI surgeries reflected in their experience (2,880) represents 36% of the estimated number worldwide as of December 2007. Cumulatively to the end of 2007, 70% of all BCI surgeries have occurred in children, with the 3- to 10-year-old age group having the highest representation (33% of all BCIs), followed in order by adults (30%), children under 3 years of age (26%), and children between 11 and 18 years of age (11%). Seventy-two percent of all BCI surgeries were performed sequentially (70% of children, 76% of adults). Children <3 years of age represent the only age group of all patients in which simultaneous surgeries predominate (58% simultaneous). For all other age groups, sequential surgeries far outnumber simultaneous (3,10 years, 84% sequential; 11,18 years, 94% sequential; adults, 76% sequential). Prior to January 2007, 68% of BCIs were performed in children. This increased to 79% for the year 2007 (P < .001). With regard to children only, a change is apparent over time in terms of the age group making up the majority of pediatric BCI surgeries performed. Prior to 2007, children 3 to 10 years of age made up 50% of the children undergoing BCI, whereas those <3 years made up only 33%. In 2007 this shifted more toward the younger age group (47% for those <3 years and 40% for 3,10-year-olds; P < .001). United States clinics had a higher proportion of adult BCI patients (59% children, 41% adults) than the non-United States clinics (78% children, 22% adults; P < .001). The majority of responders do not hold to a minimum or maximum age by which they limit BCI. Conclusions: Worldwide experience with BCI is now quite extensive and provides a useful base for evaluating clinical outcomes across patient categories and for providing further support during the patient/parent counseling process. Laryngoscope, 120:S17,S44, 2010 [source] Interleukin-1 receptor phosphorylation activates Rho kinase to disrupt human gastric tight junctional claudin-4 during Helicobacter pylori infectionCELLULAR MICROBIOLOGY, Issue 5 2010Tamia K. Lapointe Summary Helicobacter pylori infects more than half of the human population worldwide. In the absence of treatment, this persistent infection leads to asymptomatic gastritis, which in some cases can progress into gastric ulcers and adenocarcinomas. The host,microbial interactions that govern the clinical outcome of infection remain incompletely understood. H. pylori is known to disrupt gastric epithelial tight junctions, which may represent a significant component of disease pathogenesis. The present study demonstrates that H. pylori disrupt epithelial tight junctional claudin-4 in a Rho kinase (ROCK)-dependent manner in human gastric epithelial (HGE-20) cell monolayers, independently of the virulence factors CagA and VacA, and without altering claudin-4 transcription. In the same epithelial cell model, interleukin (IL)-1,, mediated a similar ROCK-dependent pattern of tight junction disruption. Further experiments revealed that H. pylori infection induced IL-1 receptor type I (IL-1RI) phosphorylation, independently of epithelial secretion of its endogenous ligands IL-1,, IL-1, or IL-18. Finally, inhibition of IL-1RI activation prevented H. pylori -induced ROCK activation and claudin-4 disruption. Taken together, these findings identify a novel pathophysiological mechanism by which H. pylori disrupts gastric epithelial barrier structure via IL-1RI-dependent activation of ROCK, which in turn mediates tight junctional claudin-4 disruption. [source] Study of the immune response in patients with uveitis and latent tuberculosisACTA OPHTHALMOLOGICA, Issue 2009D MAKHOUL Purpose Mycobacterium tuberculosis infects up to 30 % of the population worldwide. In the majority of the cases a lifelong immune response, based on the production of IFN, by CD4+ lymphocytes, restricts the infection into lung granulomas. A dysregulation of T regulatory cell function has also been implicated. It has been postulated that this constant immune response might contribute to certain forms of tuberculosis associated uveitis (hypersensitivity uveitis). The aim of this work is to analyse the lymphocyte production of IFN, and the percentage of regulatory T cells in sight threatening uveitis patients with or without latent tuberculosis. Methods Patients with sight threatening uveitis suspected to be related to tuberculosis or to autoimmune disease will be recruited at the CHU St-Pierre. Patients will be included if the work-up is compatible with the diagnosis of tuberculosis related uveitis or autoimmune uveitis used as a control. Signed informed consent will be obtained and blood samples will be taken. Results IFN, production in response to different mycobacterial peptides will be measured by QuantiFERONÔ-TB Gold in-tube and by ELISA. IL-17 will be quantified by ELISA and the percentage of T regulatory cells analysed by flow cytometry (CD3+CD4+ CD25high, CD127low, FOXP3+). Conclusion The diagnosis of tuberculosis uveitis is a clinical challenge. The disease is probably mediated through infectious and immune mechanisms. By studying the CD4 + and regulatory T lymphocytes function in patients with uveitis and latent tuberculosis, we hope that we will better understand this pathology. In addition, this study will evaluate the usefulness of QuantiFERONÔ-TB Gold in-tube in the evaluation of patient with uveitis. [source] EFFECT OF NAPROXEN, A NON-SELECTIVE CYCLO-OXYGENASE INHIBITOR, ON PENTYLENETETRAZOL-INDUCED KINDLING IN MICECLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 7 2005Ashish Dhir SUMMARY 1.,Epilepsy is one of the major neurological disorders of the brain, affecting approximately 0.5,1.0% of the population worldwide. Various neurotransmitter abnormalities, especially of GABA and glutamate, have been reported to play a key role in the pathophysiology of epilepsy. 2.,Cyclo-oxygenase (COX) is the rate-limiting enzyme in the production of prostaglandins and, as such, is a key target for many anti-inflammatory drugs. Cyclo-oxygenase has been reported to play a significant role in neurodegeneration. Recent studies have reported that COX plays a significant role in the pathophysiology of epilepsy. 3.,The aim of the present study was to explore the possible role of COX and the effect of COX inhibitors in epilepsy. 4.,Kindling is a chronic model of epilepsy. In the present study, kindling was induced in mice by chronic administration of a subconvulsive dose of pentylenetetrazole (PTZ; 40 mg/kg) on every other day for a period of 15 days. Naproxen was administered daily 45 min before PTZ or vehicle. The kindling score was recorded after PTZ administration. Seizure severity was measured according to a prevalidated scoring scale. Biochemical estimations were performed immediately after recording behavioural parameters on the 16th day of PTZ treatment. 5.,Chronic treatment with PTZ significantly induced kindling in mice. Pretreatment with the non-selective COX inhibitor naproxen (7 and 14 mg/kg, i.p.) showed significant protection against PTZ-induced kindling in mice. Biochemical analysis revealed that chronic treatment with PTZ significantly increased lipid peroxidation and nitrite levels (NO levels), but decreased reduced glutathione (GSH) levels in brain homogenates. 6.,In conclusion, the results of the present study strongly suggest that COX plays an important role in the pathophysiology of PTZ-induced kindling in mice and that COX inhibitors could be a useful neuroprotective strategy for the treatment of epilepsy. [source] Study on VNTR polymorphism of gene IL-1RA in 19 Chinese populationsINTERNATIONAL JOURNAL OF IMMUNOGENETICS, Issue 2 2010J. Jiang Summary Earlier studies suggested that a variable number tandem repeat (VNTR) polymorphism in intron 2 of the interleukin-1 receptor antagonist (IL-1RA) gene might be associated with some chronic inflammatory diseases, autoimmune diseases and solid tumours. To study the distribution of this polymorphism in China, 1352 samples were collected from 19 widely distributed Chinese populations. PCR was used to genotype the VNTR. The overall frequencies of allele 1 and allele 2 were 0.913 and 0.064 respectively. The frequency of the allele 2 was significantly different between the northeastern and the northwestern populations. Moreover, the allele frequencies at this locus in three Chinese Han populations were different from that in minority populations. When compared with other populations worldwide, the frequencies of the two alleles in China were not significantly different from those in the Asian and Pacific Islands. However, the prevalence of allele 1 in China was significantly higher, and the prevalence of allele 2 was significantly lower, than those in American and European Caucasians, and the pairwise Fst values reinforced this observation. The differences of the allele frequencies between different regions and within the same region showed that geography and race have important roles in the population differentiation for the IL-1RA gene. In summary, our results provide a valuable reference for population genetic information and future disease association studies in Chinese populations. [source] Acoustic estimation of wildlife abundance: methodology for vocal mammals in forested habitatsAFRICAN JOURNAL OF ECOLOGY, Issue 3 2010Mya E. Thompson Abstract Habitat loss and hunting pressure threaten mammal populations worldwide, generating critical time constraints on trend assessment. This study introduces a new survey method that samples continuously and non-invasively over long time periods, obtaining estimates of abundance from vocalization rates. We present feasibility assessment methods for acoustic surveys and develop equations for estimating population size. As an illustration, we demonstrate the feasibility of acoustic surveys for African forest elephants (Loxodonta africana cyclotis). Visual surveys and vocalizations from a forest clearing in the Central African Republic were used to establish that low-frequency elephant calling rate is a useful index of elephant numbers (linear regression P < 0.001, radj.2 = 0.58). The effective sampling area was 3.22 km2 per acoustic sensor, a dramatic increase in coverage over dung survey transects. These results support the use of acoustic surveys for estimating elephant abundance over large remote areas and in diverse habitats, using a distributed network of acoustic sensors. The abundance estimation methods presented can be applied in surveys of any species for which an acoustic abundance index and detection function have been established. This acoustic survey technique provides an opportunity to improve management and conservation of many acoustically-active taxa whose populations are currently under-monitored. Résumé La perte d'habitat et la pression de la chasse menacent des populations de mammifères dans le monde entier, ce qui entraîne des contraintes de temps critiques pour l'évaluation des tendances. Cette étude présente une nouvelle méthode de recherche qui échantillonne sur de longues périodes de façon constante et non intrusive et qui permet d'obtenir des estimations d'abondance à partir des taux de vocalisation. Nous présentons les méthodes d'évaluation de la faisabilité d'études acoustiques et nous développons des équations pour estimer la taille des populations. Pour illustrer ceci, nous montrons la faisabilité d'études acoustiques chez les éléphants de forêts africains Loxodonta africana cyclotis. Nous avons utilisé des études visuelles et des vocalisations d'une clairière forestière de République Centrafricaine pour établir que le taux d'appel à basse fréquence des éléphants est un indice intéressant du nombre d'éléphants (régression linéaire P < 0,001, radj² = 0,58). La superficie d'échantillonnage effective était de 3,22 km² par senseur acoustique, ce qui est une augmentation spectaculaire par rapport à la couverture des transects d'études par comptage des crottes. Ces résultats appuient le recours aux études acoustiques pour estimer l'abondance des éléphants dans de vastes zones retirées et dans des habitats variés, en utilisant un réseau de senseurs acoustiques bien répartis. Les méthodes d'estimation de l'abondance présentées peuvent être appliquées à toute espèce pour laquelle on a établi un indice d'abondance acoustique et une fonction de détection. Cette technique d'étude acoustique donne la possibilité d'améliorer la gestion et la conservation de nombreux taxons actifs au point de vue acoustique et dont les populations sont actuellement trop peu suivies. [source] Gastroschisis: International epidemiology and public health perspectives,AMERICAN JOURNAL OF MEDICAL GENETICS, Issue 3 2008Eduardo E. Castilla Abstract Gastroschisis offers the intriguing epidemiological situation of a pandemic, strongly associated with very low maternal age. Identifying gastroschisis, and distinguishing it from the other abdominal wall defects, is theoretically easy but difficult in practice. The baseline birth prevalence of gastroschisis before the pandemic was approximately 1 in 50,000 births and has increased since between 10- and 20-fold. In many populations worldwide, it is still increasing. Such increasing prevalence and the association with very low maternal age are well proven, but the interaction between these two findings remains unknown. Geographic gradients (decreasing prevalence from North to South) are clear in Continental Europe and suggestive in Britain and Ireland. Gastroschisis seems more frequent in Caucasians compared to African Blacks and Orientals, and in Northern compared to Southern Europeans. These observations indicate the need for investigating gene,environment interactions. Since the global human situation is marked by inequalities among as well as within countries, the medical care and public health impact of gastroschisis varies widely among regions and social strata. The postnatal benefits of prenatal diagnosis of gastroschisis include family awareness; adequate planning of delivery with alerted obstetrical, pediatric, and surgical staff; optimal risk categorization, and personalized protocol for action. The increasing prevalence of gastroschisis combined with improved medical techniques to reduce morbidity and mortality are also increasing the burden and costs of this anomaly on health systems. © 2008 Wiley-Liss, Inc. [source] Blood group O alleles in Native Americans: Implications in the peopling of the AmericasAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 1 2010Benito Estrada-Mena Abstract All major ABO blood alleles are found in most populations worldwide, whereas the majority of Native Americans are nearly exclusively in the O group. O allele molecular characterization could aid in elucidating the possible causes of group O predominance in Native American populations. In this work, we studied exon 6 and 7 sequence diversity in 180 O blood group individuals from four different Mesoamerican populations. Additionally, a comparative analysis of genetic diversity and population structure including South American populations was performed. Results revealed no significant differences among Mesoamerican and South American groups, but showed significant differences within population groups attributable to previously detected differences in genetic drift and founder effects throughout the American continent. Interestingly, in all American populations, the same set of haplotypes O1, O1v, and O1v(G542A) was present, suggesting the following: (1) that they constitute the main genetic pool of the founding population of the Americas and (2) that they derive from the same ancestral source, partially supporting the single founding population hypothesis. In addition, the consistent and restricted presence of the G542A mutation in Native Americans compared to worldwide populations allows it to be employed as an Ancestry informative marker (AIM). Present knowledge of the peopling of the Americas allows the prediction of the way in which the G542A mutation could have emerged in Beringia, probably during the differentiation process of Asian lineages that gave rise to the founding population of the continent. Am J Phys Anthropol, 2010. © 2009 Wiley-Liss, Inc. [source] Large Allele Frequency Differences between Human Continental Groups are more Likely to have Occurred by Drift During range Expansions than by SelectionANNALS OF HUMAN GENETICS, Issue 1 2009T. Hofer Summary Several studies have found strikingly different allele frequencies between continents. This has been mainly interpreted as being due to local adaptation. However, demographic factors can generate similar patterns. Namely, allelic surfing during a population range expansion may increase the frequency of alleles in newly colonised areas. In this study, we examined 772 STRs, 210 diallelic indels, and 2834 SNPs typed in 53 human populations worldwide under the HGDP-CEPH Diversity Panel to determine to which extent allele frequency differs among four regions (Africa, Eurasia, East Asia, and America). We find that large allele frequency differences between continents are surprisingly common, and that Africa and America show the largest number of loci with extreme frequency differences. Moreover, more STR alleles have increased rather than decreased in frequency outside Africa, as expected under allelic surfing. Finally, there is no relationship between the extent of allele frequency differences and proximity to genes, as would be expected under selection. We therefore conclude that most of the observed large allele frequency differences between continents result from demography rather than from positive selection. [source] Neurological disorders in complex humanitarian emergencies and natural disastersANNALS OF NEUROLOGY, Issue 3 2010Farrah J. Mateen MD Complex humanitarian emergencies include the relatively acute, severe, and overwhelming health consequences of armed conflict, food scarcity, mass displacement, and political strife. Neurological manifestations of complex humanitarian emergencies are important and underappreciated consequences of emergencies in populations worldwide. This review critically assesses the existing knowledge of the range of neurological disorders that accompany complex humanitarian emergencies and natural disasters in both the acute phase of crisis and the "long shadow" that follows. Ann Neurol 2010;68:282,294 [source] Thermal shock and germination in North-West European Genisteae: implications for heathland management and invasive weed control using fireAPPLIED VEGETATION SCIENCE, Issue 3 2009M.E. Hanley Abstract Question: Is the stimulation of germination by thermal shock (resulting from the passage of fire) commonly observed for Mediterranean-climate Fabaceae also apparent for NW European Genisteae (Fabaceae) species? Location: Southern England and NW France. Methods: The germination of Cytisus scopiarius, Genista anglica, Ulex europaeus, Ulex gallii and Ulex minor was examined following exposure to a range of temperatures (50°C, 65°C, 80°C, 95°C and 110°C) applied to seeds for 5 min. A sixth Mediterranean-origin species (Spartium junceum) was also included since it is a common invasive in NW Europe and North America. Results: All five native NW European species displayed increased germination following thermal shock, even when seeds were heated to 110°C. However, there was some variation depending on provenance: in contrast to seeds collected from southern England, germination of French C. scopiarius seeds was unaffected by temperature. Spartium junceum germinated most at 95°C, but was the only species to show reduced germination when seeds were heated to 110°C. Conclusions: The NW European Genisteae appear to be pre-adapted to the high temperatures associated with fire; a response attributable to their evolutionary origins in the fire-prone ecosystems of the Mediterranean Basin. Consequently, projected increases in fire frequency linked to climate change may stimulate their regeneration in NW European heathlands, potentially altering the species composition of these ecosystems. Additionally, a clearer understanding of the interaction between thermal shock and germination may explain why fire has so frequently been ineffective in controlling invasive Genisteae populations worldwide. [source] Accuracy of clinical diagnosis of skin lesionsBRITISH JOURNAL OF DERMATOLOGY, Issue 3 2008C.F. Heal Summary Background, Skin cancer is an increasing problem in fair-skinned populations worldwide. It is important that doctors are able to diagnose skin lesions accurately. Objectives, To compare the clinical with the histological diagnosis of excised skin lesions from a set of epidemiological data. We analysed diagnostic accuracy stratified by histological subtype and body site and examined the histological nature of misclassified diagnosis. Methods, All excised and histologically confirmed skin cancers in Townsville/Thuringowa, Australia from December 1996 to October 1999 were recorded. Positive predictive values (PPVs) and sensitivities were calculated for the clinical diagnoses and stratified by histological subtype and body site. Results, Skin excisions in 8694 patients were examined. PPVs for the clinical diagnoses were: basal cell carcinoma (BCC) 72·7%; squamous cell carcinoma (SCC) 49·4%; cutaneous melanoma (CM) 33·3%. Sensitivities for the clinical diagnosis were: BCC 63·9%; SCC 41·1%; CM 33·8%. For BCC, PPVs and sensitivities were higher for the trunk, the shoulders and the face and lower for the extremities. The reverse pattern was seen for SCCs. Conclusions, Diagnostic accuracy was highest for BCC, the most prevalent lesion. Most excisions were correctly diagnosed or resulted in the removal of malignant lesions. With nonmelanocytic lesions, doctors tended to misclassify benign lesions as malignant, but were less likely to do the reverse. Although a small number of clinically diagnosed common naevi subsequently proved to be melanoma (6·3%), a higher proportion of all melanomas had been classified as common naevi (20·9%). Accuracy of diagnosis was dependent on body site. [source] | |||||||||||||