978 resultados para 14-3-3 Proteins
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BACKGROUND: Risk factors for early mortality after pulmonary embolism (PE) are widely known. However, it is uncertain which factors are associated with early readmission after PE. We sought to identify predictors of readmission after an admission for PE. METHODS: We studied 14 426 patient discharges with a primary diagnosis of PE from 186 acute care hospitals in Pennsylvania from January 1, 2000, to November 30, 2002. The outcome was readmission within 30 days of presentation for PE. We used a discrete proportional odds model to study the association between time to readmission and patient factors (age, sex, race, insurance, discharge status, and severity of illness), thrombolysis, and hospital characteristics (region, teaching status, and number of beds). RESULTS: Overall, 2064 patient discharges (14.3%) resulted in a readmission within 30 days of presentation for PE. The most common reasons for readmission were venous thromboembolism (21.9%), cancer (10.8%), pneumonia (5.2%), and bleeding (5.0%). In multivariable analysis, African American race (odds ratio [OR], 1.19; 95% confidence interval [CI], 1.02-1.38), Medicaid insurance (OR, 1.54; 95% CI, 1.31-1.81), discharge home with supplemental care (OR, 1.40; 95% CI, 1.27-1.54), leaving the hospital against medical advice (OR, 2.84; 95% CI, 1.80-4.48), and severity of illness were independently associated with readmission; readmission also varied by hospital region. CONCLUSIONS: Early readmission after PE is common. African American race, Medicaid insurance, severity of illness, discharge status, and hospital region are significantly associated with readmission. The high readmission rates for venous thromboembolism and bleeding suggest that readmission may be linked to suboptimal quality of care in the management of PE.
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BACKGROUND: We analysed 5-year treatment with agalsidase alfa enzyme replacement therapy in patients with Fabry's disease who were enrolled in the Fabry Outcome Survey observational database (FOS). METHODS: Baseline and 5-year data were available for up to 181 adults (126 men) in FOS. Serial data for cardiac mass and function, renal function, pain, and quality of life were assessed. Safety and sensitivity analyses were done in patients with baseline and at least one relevant follow-up measurement during the 5 years (n=555 and n=475, respectively). FINDINGS: In patients with baseline cardiac hypertrophy, treatment resulted in a sustained reduction in left ventricular mass (LVM) index after 5 years (from 71.4 [SD 22.5] g/m(2.7) to 64.1 [18.7] g/m(2.7), p=0.0111) and a significant increase in midwall fractional shortening (MFS) from 14.3% (2.3) to 16.0% (3.8) after 3 years (p=0.02). In patients without baseline hypertrophy, LVM index and MFS remained stable. Mean yearly fall in estimated glomerular filtration rate versus baseline after 5 years of enzyme replacement therapy was -3.17 mL/min per 1.73 m(2) for men and -0.89 mL/min per 1.73 m(2) for women. Average pain, measured by Brief Pain Inventory score, improved significantly, from 3.7 (2.3) at baseline to 2.5 (2.4) after 5 years (p=0.0023). Quality of life, measured by deviation scores from normal EuroQol values, improved significantly, from -0.24 (0.3) at baseline to -0.17 (0.3) after 5 years (p=0.0483). Findings were confirmed by sensitivity analysis. No unexpected safety concerns were identified. INTERPRETATION: By comparison with historical natural history data for patients with Fabry's disease who were not treated with enzyme replacement therapy, long-term treatment with agalsidase alfa leads to substantial and sustained clinical benefits. FUNDING: Shire Human Genetic Therapies AB.
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For the first time, a survey on Giardia in the live-trapped small domestic and wild mammals was perfomed in four regions of state of the São Paulo, Brazil, with special attention to the parasitism of Rattus rattus rattus by Giardia. This species was found infected in all studied sites: Botucatu (15.4%), Conchas (28.5%), Itaporanga (38.7%) and São Roque (100 %). Two new hosts and their frequency of infection were described for Giardia in Nectomys squamipes, an aquatic rodent and in Bolomys lasiurus, a forest rodent (100 % and 14.3 %, respectively). Both G. muris and G. duodenalis groups were found in scrapings of intestinal mucosa of those rodents. Mixed infection was observed in some animals. It is important to emphasize the infection by G. duodenalis in the black rat as this species lives as a comensal with man and in N. squamipes as it may contaminate small streams used for domestic consumption. Therefore, further investigation will be necessary to elucidate the potential of these rodents to act as reservoirs of Giardia for man.
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AIM: To determine the prevalence and characteristics of pain in Thai human immunodeficiency virus-infected children. METHODS: A cross-sectional study was performed at the HIV/AIDS outpatient clinic at the Queen Sirikit National Institute of Child Health, Bangkok, Thailand from November 2002 to January 2003. Sixty-one human immunodeficiency virus-infected patients aged 4 to 15 y, an equal number of age-matched children with no chronic disease and their caregivers participated. We interviewed children and their caregivers using a structured questionnaire on pain. The main outcome measure was the percentage of human immunodeficiency virus-infected children reporting pain. RESULTS: Forty-four percent of the human immunodeficiency virus-infected children reported pain compared to 13% of the children with no chronic disease (odds ratio, OR = 5.3; 95% CI: 2.0-14.3). Seven percent of the infected children experienced chronic pain. Children in human immunodeficiency virus clinical categories B and C reported more pain than children in categories N and A (OR = 4.0, 95% CI: 1.1-14.7). Pain in infected children tended to occur in the abdomen, lower limbs or head. Only 44 percent of the infected children experiencing pain received analgesic medication. CONCLUSION: Despite being a common experience, pain is insufficiently taken into account and treated in Thai children with HIV/AIDS. Therefore, adequate pain identification, assessment and management should be systemically considered in their routine care.
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RESUME Introduction : Les naissances prématurées compliquent 6-10 % des grossesses dans les pays industrialisés et contribuent de façon notable aux taux de mortalité périnatale et de morbidité néonatale. Il a été démontré que la colonisation bactérienne du liquide amniotique joue un rôle dans l'étiologie des accouchements prématurés spontanés et des ruptures prématurées des membranes. Le but de ce travail était d'évaluer la présence de Mycoplasma hominis dans le liquide amniotique prélevé au 2eme trimestre de grossesse chez des patientes asymptomatiques et de déterminer son association avec une issue défavorable de la grossesse. Matériels et méthodes : Les échantillons de liquide amniotique de 456 patientes ayant subi une amniocentèse trans-abdominale entre les 15eme et I7eme semaines de grossesse pour diverses indications ont été testés par PCR (Polymerase Chain Reaction) afin d'identifier Mycoplasma hominis. Les produits ainsi amplifiés étaient ensuite détectés par ELISA (Enzyme-Linked Immunosorbent Assay). Les données cliniques étaient obtenues après l'accouchement. Résultats : Mycoplasma hominis a été identifié dans 29 (6,4%) des échantillons de liquide amniotique. Le taux de menace d'accouchement prématuré chez les patientes positives pour Mycoplasma hominis (14,3%) était plus élevé que chez les patientes négatives (3,3 %) (p=0,01). De même, les naissances prématurées spontanées avec membranes intactes étaient plus fréquentes chez les patientes positives (10,7%) que chez les patientes négatives (1,9 %) (p=0,02). Le taux de menace d'accouchement prématuré lors d'une grossesse antérieure était plus de trois fois plus élevé chez les patientes positives, cependant ce résultat n'était pas statistiquement significatif. Finalement, la présence du mycoplasme n'était pas corrélée à la gestose, au retard de croissance intra-utérin ou aux anomalies chromosomiques foetales. Conclusions : Les résultats montrent que la présence de Mycoplasma hominis dans le liquide amniotique prélevé entre les 15eme et I7eme semaines d' aménorrhée chez des patientes asymptomatiques est associée à un taux plus élevé de menace d'accouchement prématuré et de naissances prématurées spontanées. La détection de ce microorganisme au 2eme trimestre de la grossesse peut donc identifier les patientes à risque de menace d'accouchement et de naissance prématurées. Abstract Objective: The relationship between detection of Mycoplasma hominis in mid-trimester amniotic fluid and subsequent pregnancy outcome was investigated. Study design: Amniotic fluids from 456 women of European background who underwent a transabdominal amniocentesis at weeks 15-17 of pregnancy were tested for M. hominis by polymerase chain reaction (PCR). The amplicons were hybridized to an internal probe and detected by ELISA. Pregnancy outcomes and clinical data were subsequently obtained. Results: M. hominis were identified in 29 (6.4%) of the amniotic fluids. The rate of preterm labor in women positive for M. hominis (14.3%) was higher than in the negative women (3.3%) (p = 0.01). Similarly, a spontaneous preterm birth with intact membranes occurred in 10.7% of the M. hominis-posltive women as opposed to only 1.9% of the negative women (p = 0.02). The presence of this mycoplasma was not correlated with fetal chromosomal aberrations, intrauterine growth restriction or preeclampsia. Conclusions: Detection of M. hominis in second-trimester amniotic fluids can identify women at increased risk for subsequent preterm labor and delivery.
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Objectives: To investigate the associations between falls before¦hospital admission, falls during hospitalization, and length of stay in¦elderly people admitted to post-acute geriatric rehabilitation.¦Method: History of falling in the previous 12 months before admission¦was recorded among 249 older persons (mean age 82.3 ± 7.4 years,¦69.1% women) consecutively admitted to post-acute rehabilitation. Data¦on medical, functional and cognitive status were collected upon¦admission. Falls during hospitalization and length of stay were recorded¦at discharge.¦Results: Overall, 92 (40.4%) patients reported no fall in the 12 months¦before admission; 63(27.6%) reported 1 fall, and 73 (32.0%) reported¦multiple falls. Previous falls occurrence (one or more falls) was¦significantly associated with in-stay falls (19.9% of previous fallers fell¦during the stay vs 7.6% in patients without history of falling, P = .01),¦and with a longer length of stay (22.4 ± 10.1 days vs 27.1 ± 14.3 days,¦P = .01). In multivariate robust regression controlling for gender, age,¦functional and cognitive status, history of falling remained significantly¦associated with longer rehabilitation stay (2.8 days more than non¦fallers in single fallers, p = .05, and 3.3 days in multiple fallers, p = .0.1).¦Conclusion: History of falling in the 12 months prior to post acute¦geriatric rehabilitation is independently associated with a longer¦rehabilitation length of stay. Previous fallers also have an increased risk¦of falling during rehabilitation stay. This suggests that hospital fall¦prevention measures should particularly target these high risk patients.
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OBJECTIVE: To investigate the relationship between levels of cognitive impairment and health services utilization in older patients undergoing post-acute rehabilitation. DESIGN: Cross-sectional study. SETTING: Post-acute rehabilitation facility. PARTICIPANTS: Patients (N = 1764) aged 70 years and older admitted over 3 years. MEASUREMENTS: Sociodemographic, medical, and functional data were collected upon admission. Based on discharge diagnoses, patients were classified as cognitively intact, cognitively impaired with no dementia (CIND), and demented. RESULTS: Dementia and CIND were diagnosed in 425 (24.1%) and 301 (17.1%) patients, respectively. Gradients from cognitively intact to cognitively impaired to demented patients were observed in median length of stay (19, 22, and 25 days, P < .001), and institutionalization rates at discharge (4.2%, 7.6%, and 28.8%, P < .001). Among patients discharged home, similar gradients were observed in utilization of home care (68.2%, 79.7%, and 83.3%, P < .001) and day care (3.1%, 7.1%, and 14.3%, P < .001). After adjustment, compared with cognitively intact patients, only those with dementia still had longer stays (+2.7 days) and increased odds of institutionalization (adjOR 6.1, 95% CI 4.0-9.3, P < .001). Among patients discharged home, use of home and day care remained higher in those with dementia (adjOR 1.8, 95% CI 1.2-2.7, P = .005, and adjOR 1.8, 95% CI 1.2-2.7, P = .005, respectively), while CIND patients had higher odds of using home care (adjOR 1.6, 95% CI 1.1-2.4, P = .028). CONCLUSION: Among patients undergoing post-acute rehabilitation, those with dementia had increased use of both institutional and community care, whereas those with CIND had increased use of home care services only. Future studies should investigate specific strategies susceptible to reduce the related burden on health care systems.
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QUESTIONS UNDER STUDY AND PRINCIPLES: Estimating glomerular filtration rate (GFR) in hospitalised patients with chronic kidney disease (CKD) is important for drug prescription but it remains a difficult task. The purpose of this study was to investigate the reliability of selected algorithms based on serum creatinine, cystatin C and beta-trace protein to estimate GFR and the potential added advantage of measuring muscle mass by bioimpedance. In a prospective unselected group of patients hospitalised in a general internal medicine ward with CKD, GFR was evaluated using inulin clearance as the gold standard and the algorithms of Cockcroft, MDRD, Larsson (cystatin C), White (beta-trace) and MacDonald (creatinine and muscle mass by bioimpedance). 69 patients were included in the study. Median age (interquartile range) was 80 years (73-83); weight 74.7 kg (67.0-85.6), appendicular lean mass 19.1 kg (14.9-22.3), serum creatinine 126 μmol/l (100-149), cystatin C 1.45 mg/l (1.19-1.90), beta-trace protein 1.17 mg/l (0.99-1.53) and GFR measured by inulin 30.9 ml/min (22.0-43.3). The errors in the estimation of GFR and the area under the ROC curves (95% confidence interval) relative to inulin were respectively: Cockcroft 14.3 ml/min (5.55-23.2) and 0.68 (0.55-0.81), MDRD 16.3 ml/min (6.4-27.5) and 0.76 (0.64-0.87), Larsson 12.8 ml/min (4.50-25.3) and 0.82 (0.72-0.92), White 17.6 ml/min (11.5-31.5) and 0.75 (0.63-0.87), MacDonald 32.2 ml/min (13.9-45.4) and 0.65 (0.52-0.78). Currently used algorithms overestimate GFR in hospitalised patients with CKD. As a consequence eGFR targeted prescriptions of renal-cleared drugs, might expose patients to overdosing. The best results were obtained with the Larsson algorithm. The determination of muscle mass by bioimpedance did not provide significant contributions.
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Objectives:To investigate the associations between falls before hospital¦admission, falls during hospitalization, and length of stay in elderly¦people admitted to post-acute geriatric rehabilitation. Method: History¦of falling in the previous 12 months before admission was recorded¦among 249 older persons (mean age 82.3±7.4 years, 69.1% women)¦consecutively admitted to post-acute rehabilitation. Data on medical,¦functional and cognitive status were collected upon admission. Falls¦during hospitalization and length of stay were recorded at discharge.¦Results: Overall, 92 (40.4%) patients reported no fall in the 12 months¦before admission; 63(27.6%) reported 1 fall, and 73(32.0%) reported¦multiple falls. Previous falls occurrence (one or more falls) was significantly¦associated with in-stay falls (19.9% of previous fallers fell¦during the stay vs 7.6% in patients without history of falling, P=.01),¦and with a longer length of stay (22.4 ± 10.1 days vs 27.1 ± 14.3 days,¦P=.01). In multivariate robust regression controlling for gender, age,¦functional and cognitive status, history of falling remained significantly¦associated with longer rehabilitation stay (2.8 days more in single fallers,¦p=.05, and 3.3 days more in multiple fallers, p=.0.1, compared to¦non-fallers). Conclusion: History of falling in the 12 months prior to¦post acute geriatric rehabilitation is independently associated with a¦longer rehabilitation length of stay. Previous fallers have also an¦increased risk of falling during rehabilitation stay. This suggests that¦hospital fall prevention measures should particularly target these high¦riskpatients.
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A kit based on an enzyme immunoassay, EIE-Recombinant-Chagas-Biomanguinhos, developed by the Oswaldo Cruz Foundation, was evaluated for the serodiagnosis of chronic Chagas disease. Evaluation was performed with 368 serum samples collected from individuals living in an endemic area for Chagas disease: 131 patients in the chronic phase with confirmed clinical, epidemiological, and serological diagnosis (indirect immunofluorescence, indirect hemagglutination or enzyme-linked immunosorbent assay) and 237 nonchagasic seronegative individuals were considered negative control. The EIE-Recombinant-Chagas-Biomanguinhos kit showed high sensitivity, 100% (CI 95%: 96.4-100%) and high specificity, 100% (CI 95%: 98-100%). The data obtained were in full agreement with clinical and conventional serology data. In addition, no cross-reaction was observed with sera from patients with cutaneous (n=14) and visceral (n=3) leishmaniasis. However, when these sera were tested by conventional serological assays for Chagas disease, cross-reactions were detected in 14.3% and 33.3% of the patients with cutaneous and visceral leishmaniasis, respectively. No cross-reactions were observed when sera from nonchagasic seronegative patients bearing other infectious disease (syphilis, n=8; HTLV, n=8; HCV, n=7 and HBV, n=12) were tested. In addition, sera of patients with inconclusive results for Chagas disease by conventional serology showed results in agreement with clinical evaluation, when tested by the kit. These results are relevant and indicate that the refered kit provides a safe immunodiagnosis of Chagas disease and could be used in blood bank screening.
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A group of 52 villagers was followed-up for three years regarding Schistosoma mansoni infection. All villagers were periodically surveyed by the Kato-Katz method. In March 1997 and March 1998 the positives were treated with oxamniquine (15-20 mg/kg), and in March 1999, with praziquantel (60 mg/kg). All infection indices decreased substantially between March 1999 and March 2000: prevalence of infection (from 32.7% to 21.2%), prevalence of moderate/heavy infection (from 7.7% to 1.9%), intensity of infection (from 23.1 epg to 7.4 epg) and reinfection (from 35.7% to 14.3%). Negativation increased from 53.8 to 82.4. An optimistic prognostic is assumed in the short term for the introduction of praziquantel in the study area.
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The sewage snail Physa acuta is a serious threat to certain economic plants and to the purification plant of sewage works by rendering the biofilters ineffective. Various attempts are being made to control it. The efficacy of the predacious water bugs Sphaerodema rusticum was judged experimentally, in the laboratory in the potential control of P. acuta. It is revealed that, when supplied separately, the first, second and third instar and the adult S. rusticum did not attack P. acuta belonging to 3.1-8 mm, 5.1-8 mm, 7.1-8 mm and <= 3 mm size classes respectively. In the remaining trials predation rate varied from zero to eight (average 2.3) individuals per predator per day. In experiments with P. acuta belonging to all the size classes supplied together, none, except the first instar S. rusticum, attacked the prey individuals belonging to the lowest (<= 3 mm) size class. The first and second instar S. rusticum, in both trials did not attack P. acuta larger than 4 mm and 5 mm in shell length respectively. The water bugs belonging to the third, fourth, fifth instar and adult stages though preyed upon P. acuta with 3.1-8 mm shell length. The average rate of predation by a single S. rusticum varied from 0.14-3.08 individuals per day depending upon the size of P. acuta and the stage of S. rusticum. A single S. rusticum, irrespective of instar and adult stages, destroyed on average 4.16 P. acuta daily irrespective of sizes. It is estimated that one S. rusticum could destroy 1,360 P. acuta in its life time. The results clearly indicate that the water bug S. rusticum may be used to control the snails P. acuta.
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Information is very scarce on the prevalence of hepatitis-B virus (HBV) infection among blood donors and patients with human immunodeficiency virus (HIV) infection in Nigeria. Hepatitis-B surface antigen (HBsAg) ELISA was used to determined the prevalence of HBsAg among 175 blood donors (aged 20-40 years) and 490 HIV-infected patients (aged 17-60 years) in Jos, Nigeria. Twenty-five (14.3%) of the blood donors and 127 (25.9%) of the HIV-infected individuals were HBsAg seropositive, indicating a higher HBV infection among HIV-infected persons than among healthy blood donors. A slightly higher HBsAg seroprevalence was recorded in the males (14.6%) than females (12.9%) of the blood donors. Among the HIV-infected patients, the males had considerably higher HBsAg seroprevalence than the females (31.8 vs 22.1%) with the highest prevalence of HBsAg occurring in the 51-60 years age group (44%), followed by those of 31-40 years (28.2%). Results confirmed the high endemicity of HBV infection in Jos, Nigeria and the significantly greater prevalence of HBV infection among HIV -infected patients than among blood donors.
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This report gives a comprehensive and up-to-date review of Alzheimer's disease biomarkers. Recent years have seen significant advances in this field. Whilst considerable effort has focused on A�_ and tau related markers, a substantial number of other molecules have been identified, that may offer new opportunities.This Report : Identifies 60 candidate Alzheimer's (AD) biomarkers and their associated studies. Of these, 49 are single species or single parameters, 7 are combinations or panels and 4 involve the measurement of two species or parameters or their ratios. These include proteins (n=34), genes (n=11), image-based parameters (n=7), small molecules (n=3), proteins + genes (n=2) and others (n=3). Of these, 30 (50%) relate to species identified in CSF and 19 (32%) were found in the blood. These candidate may be classified on the basis of their diagnostic utility, namely those which i) may allow AD to be detected when the disease has developed (48 of 75†= 64%), ii) may allow early detection of AD (18 of 75† = 24%) and iii) may allow AD to be predicted before the disease has begun to develop (9 of 75†= 12%). † Note: Of these, 11 were linked to two or more of these capabilities (e.g. allowed both early-stage detection as well as diagnosis after the disease has developed).Biomarkers: AD biomarkers identified in this report show significant diversity, however of the 60 described, 18 (30%) are associated with amyloid beta (A�_) and 9 (15%) relate to Tau. The remainder of the biomarkers (just over half) fall into a number of different groups. Of these, some are associated with other hypotheses on the pathogenesis of AD however the vast majority are individually unique and not obviously linked with other markers. Analysis and discussion presented in this report includes summaries of the studies and clinical trials that have lead to the identification of these markers. Where it has been calculated, diagnostic sensitivity, specificity and the capacity of these markers to differentiate patients with suspected AD from healthy controls and individuals believed to be suffering from other neurodegenerative conditions, have been indicated. These findings are discussed in relation to existing hypotheses on the pathogenesis of the AD and the current drug development pipeline. Many uncertainties remain in relation to the pathogenesis of AD, in diagnosing and treating the disease and many of the studies carried out to identify disease markers are at an early stage and will require confirmation through larger and longer investigations. Nevertheless, significant advances in the identification of AD biomarkers have now been made. Moreover, whilst much of the research on AD biomarkers has focused on amyloid and tau related species, it is evident that a substantial number of other species may provide important opportunities.Purpose of Report: To provide a comprehensive review of important and recently discovered candidate biomarkers of AD, in particular those with potential to reliably detect the disease or with utility in clinical development, drug repurposing, in studies of the pathogenesis and in monitoring drug response and the course of the disease. Other key goals were to identify markers that support current pipeline developments, indicate new potential drug targets or which advance understanding of the pathogenesis of this disease.Drug Repurposing: Studies of the pathogenesis of AD have identified aberrant changes in a number of other disease areas including inflammation, diabetes, oxidative stress, lipid metabolism and others. These findings have prompted studies to evaluate some existing approved drugs to treat AD. This report identifies studies of 9 established drug classes currently being investigated for potential repurposing.Alzheimer’s Disease: In 2005, the global prevalence of dementia was estimated at 25 million, with more than 4 million new cases occurring each year. It is also calculated that the number of people affected will double every 20 years, to 80 million by 2040, if a cure is not found. More than 50% of dementia cases are due to AD. Today, approximately 5 million individuals in the US suffer from AD, representing one in eight people over the age of 65. Direct and indirect costs of AD and other forms of dementia in the US are around $150 billion annually. Worldwide, costs for dementia care are estimated at $315 billion annually. Despite significant research into this debilitating and ultimately fatal disease, advances in the development of diagnostic tests for AD and moreover, effective treatments, remain elusive.Background: Alzheimer's disease is the most common cause of dementia, yet its clinical diagnosis remains uncertain until an eventual post-mortem histopathology examination is carried out. Currently, therapy for patients with Alzheimer disease only treats the symptoms; however, it is anticipated that new disease-modifying drugs will soon become available. The urgency for new and effective treatments for AD is matched by the need for new tests to detect and diagnose the condition. Uncertainties in the diagnosis of AD mean that the disease is often undiagnosed and under treated. Moreover, it is clear that clinical confirmation of AD, using cognitive tests, can only be made after substantial neuronal cell loss has occurred; a process that may have taken place over many years. Poor response to current therapies may therefore, in part, reflect the fact that such treatments are generally commenced only after neuronal damage has occurred. The absence of tests to detect or diagnose presymptomatic AD also means that there is no standard that can be applied to validate experimental findings (e.g. in drug discovery) without performing lengthy studies, and eventual confirmation by autopsy.These limitations are focusing considerable effort on the identification of biomarkers that advance understanding of the pathogenesis of AD and how the disease can be diagnosed in its early stages and treated. It is hoped that developments in these areas will help physicians to detect AD and guide therapy before the first signs of neuronal damage appears. The last 5-10 years have seen substantial research into the pathogenesis of AD and this has lead to the identification of a substantial number of AD biomarkers, which offer important insights into this disease. This report brings together the latest advances in the identification of AD biomarkers and analyses the opportunities they offer in drug R&D and diagnostics.��
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A differentiated reconstruction of palaeolimnologic, -environmental, and -climatic conditions is presented for the Middle Miocene long-term freshwater lake (14.3 to 13.5 Ma) of the Steinheim basin, on the basis of a combined C, 0, and Sr isotope study of sympatric skeletal fossils of aquatic and terrestrial organisms from the lake sediments. The oxygen isotope composition for lake water of the Steinheim basin (delta O-18(H2O) = +2.0 +/- 0.4 parts per thousand VSMOW, n = 6) was reconstructed from measurements of delta O-18(PO4) of aquatic turtle bones. The drinking water calculated from the enamel of large mammals (proboscideans, rhinocerotids, equids, cervids, suids) has delta O-18(H2O) values (delta(OH2O)-O-18 = -5.9 +/- 1.7 parts per thousand VSMOW, n = 31) typical for Middle Miocene meteoric water of the area. This delta O-18(H2O) value corresponds to a mean annual air temperature (MAT) of 18.8 +/- 3.8 degrees C, calculated using a modem-day delta(OH2O)-O-18-MAT relation. Hence, large mammals did not use the lake water as principal drinking water. In contrast, small mammals, especially the then abundant pika Prolagus oeningensis drank from O-18-enriched water sources (delta O-18(H2O) = +2.7 +/- 2.3 parts per thousand VSMOW, n = 7), such as the lake water. Differences in Sr and 0 isotopic compositions between large and small mammal teeth indicate different home ranges and drinking behaviour and support migration of some large mammals between the Swabian Alb plateau and the nearby Molasse basin, while small mammals ingested their food and water locally. Changes in the lake level, water chemistry, and temperature were inferred using isotopic compositions of ostracod and gastropod shells from a composite lake sediment profile. Calcitic ostracod valves (Ilyocypris binocularis; delta O-18 = +1.7 +/- 1.2 parts per thousand VPDB, delta C-18 = -0.5 +/- 0.9 parts per thousand, VPDB, n = 68) and aragonitic, gastropod shells (Gyraulus spp.; delta O-18 = +2.0 +/- 13 parts per thousand VPDB, delta C-13 = -1.1 +/- 1.3 parts per thousand VPDB, n = 89) have delta O-18 and delta C-13 values similar to or even higher than those of marine, carbonates. delta C-13 values:of the biogenic carbonates parallel lake level fluctuations while delta O-18 values scatter around +2 +/- 2 parts per thousand and reflect the short term variability of meteoric water inflow vs. longer term evaporation. Sr-87/Sr-86 ratios of aragonitic Gyraulus spp. gastropod shells parallel the lake level fluctuations, reflecting variable inputs of groundwater and surface waters. Using a water delta O-18(H2O) value of +2.0 parts per thousand VSMOW, water temperatures calculated from skeletal tissue delta O-18 values of ostracods are 16.7 +/- 5.0 degrees C, gastropods 20.6 +/- 5.6 degrees C, otoliths 21.8 +/- 1.4 degrees C, and fish teeth 17.0 +/- 2.7 degrees C. The calculated MAT (similar to 19 degrees C), lake water temperatures (similar to 17 to 22 degrees C) and the O-18-enriched water compositions are indicative of warm-temperate climatic conditions, possibly with a high humidity during this period. Vegetation in the area surrounding the basin was largely of the C-3-type, as indicated by carbon isotopic compositions of tooth enamel from large mammals (delta C-13 = -11.1 +/- 1.1 parts per thousand VPDB, n = 40). (c) 2006 Elsevier B.V. All rights reserved.