499 research outputs found
Selenium and Other Trace Elements in the Etiology of Parkinson's Disease: A Systematic Review and Meta-Analysis of Case-Control Studies
Background: Parkinson's disease (PD) is the most common neurodegenerative disease after Alzheimer's dementia. Whereas the exact etiology of PD remains unknown, risk of developing PD seems to be related to a combination of genetic and environmental factors. This also includes abnormal exposure to trace elements of nutritional and toxicological interest. Objectives: In this systematic review and meta-Analysis, we summarized the results of case-control studies comparing levels of selenium, copper, iron, and zinc in PD patients and controls in either blood (whole blood, serum/plasma) or cerebrospinal fluid (CSF). Methods: We performed a systematic PubMed search selecting studies reporting trace element levels in different specimens of patients and controls. We performed a meta-Analysis using a random-effect model to compute the weighted mean differences (WMD) and corresponding 95% CI of selenium, copper, iron, and zinc levels in the blood or CSF of patients and their matched controls. Results: We retrieved 56 papers reporting data for selenium (cases/controls: 588/721), copper (2,190/2,522), iron (2,956/3,469), and zinc (1,798/1,913) contents in CSF and blood. Cases showed considerably higher levels of selenium in CSF compared with controls (+51.6%; WMD 5.49; 95% CI 2.82 to 8.15), while levels in serum were similar (-0.2%; WMD-0.22; 95% CI-8.05 to 7.62). For copper, cases showed slightly higher levels in CSF and slightly lower concentrations in serum (+4.5%; WMD 1.87; 95% CI-3.59 to 7.33, and-4.5%; WMD-42.79; 95% CI-134.35 to 48.76, respectively). A slight increase was also found for CSF iron-levels (+9.5%; WMD 9.92; 1.23 to 18.61), while levels were-decreased in serum/plasma (-5.7%; WMD-58.19; 95% CI-106.49 to-9.89) and whole blood (-10.8%; WMD-95.69; 95% CI-157.73 to-33.65). Conversely, for zinc cases exhibited lower levels both in CSF (-10.8%; WMD-7.34; 95% CI-14.82 to 0.14) and serum/plasma (-7.5%; WMD-79.93; 95% CI-143.80 to-16.06). A longer duration of the disease tends to be associated with overall lower trace element levels in either CSF or blood. Conclusions: Due to the study findings and the greater relevance of the CSF compartment compared with the circulating peripheral ones, this meta-Analysis suggests that overexposure in the central nervous system to selenium, and possibly to copper and iron, may be a risk factor of the disease, while zinc might have a protective-effect
Selenium and other trace elements in the etiology of Parkinson’s disease: a systematic review and meta-analysis of case-control studies
.INTRODUCTION
Parkinson’s disease (PD) is a neurodegenerative illness recognised as the most common neurological disorder after Alzheimer’s dementia. Whereas the exact PD etiology remains unknown, risk of developing PD seems to be related to an interrelation of genetic and environmental factors, including also altered exposure to trace elements. In this systematic review and meta-analysis, we updated and summarized the results of epidemiologic case-control studies comparing levels of selenium, copper, iron and zinc in PD patients with healthy subjects in either blood (as whole blood, serum or plasma) and cerebrospinal fluid (CSF).
MATERIALS AND METHODS
We performed a systematic PubMed search and we included in our assessment only studies reporting demographic and disease-related characteristics, as well as trace element levels in different specimens (whole blood, serum/plasma and CSF). We then performed a meta-analysis of mean differences of trace element levels between cases and controls, using a random-effect model computing the weighted mean differences (WMD) and corresponding 95% confidence intervals (CI) to assess the association between serum/plasma, whole blood, CSF and selenium, copper, iron and zinc with Parkinson’s disease.
RESULTS
We retrieved 55 papers reporting data for selenium (588 cases and 721 controls), copper (2190 and 2522), iron (2843 and 3434), and zinc (1798 and 1913). Cases showed higher levels of selenium in CSF compared with controls (WMD=5.49; 95%CI 2.82 to 8.15), while levels in serum were similar (WMD=-0.22; -8.05 to 7.62). For copper cases showed higher levels in CSF and lower in serum compared to controls (WMD=1.87; -3.59 to 7.33, and -42.79, -134.35 to 48.76 respectively). Same results were found for iron in CSF (WMD=6.54; -1.97 to 15.04) and in serum/plasma (WMD=-58.19; -106.49 to -9.89 and whole blood (WMD=-95.69; 157.73 to -33.65). On the converse, cases had lower levels of zinc both in CSF (WMD=-7.34; -14.82 to 0.14) and serum/plasma (WMD=-79.93; -143.80 to -16.06).
CONCLUSIONS
Results of this systematic review and meta-analysis suggests that overexposure to environmental selenium, copper and iron may be risk factors for PD onset or progression. Alternatively, some variation in levels of these trace elements may occur as a consequence of the disease. Considering the burden of PD in the world population, further investigation of trace element exposure in this disease is therefore warranted, especially to plan possible prevention measures
Characterization of partially accessible anisotropic spin chains in the presence of anti-symmetric exchange
We address quantum characterization of anisotropic spin chains in the presence of anti-symmetric exchange, and investigate whether the Hamiltonian parameters of the chain may be estimated with precision approaching the ultimate limit imposed by quantum mechanics. At variance with previous approaches, we focus on the information that may be extracted by measuring only two neighboring spins rather than a global observable on the entire chain. We evaluate the Fisher information (FI) of a two-spin magnetization measure, and the corresponding quantum Fisher
information (QFI), for all the relevant parameters, i.e. the spin coupling, the anisotropy, and the Dzyaloshinskii–Moriya (DM) parameter. Our results show that the reduced system made of two neighboring spins may be indeed exploited as a probe to characterize global properties of the entire system. In particular, we find that the ratio between the FI and the QFI is close to unit for a large range of the coupling values. The DM coupling is beneficial for coupling estimation, since it leads
to the presence of additional bumps and peaks in the FI and QFI, which are not present in a model that neglects exchange interaction and may be exploited to increase the robustness of the overall estimation procedure. Finally, we address the multiparameter estimation problem, and show that the model is compatible but sloppy, i.e. both the Uhlmann curvature and the determinant of the QFI matrix vanish. Physically, this means that the state of the system actually depends only on a
reduced numbers of combinations of parameters, and not on all of them separately
Kesuburan Perairan Ditinjau dari Kandungan Klorofil-a Fitoplankton : Studi Kasus di Sungai Wedung, Demak
Perairan Sungai Wedung merupakan ekosistem pesisir yang banyak dimanfaatkan untuk berbagai kegiatan manusia. Hal tersebut tentunya berpengaruh terhadap kesuburan perairan Sungai Wedung. Kesuburan di perairan tersebut dipengaruhi oleh plankton, faktor kimia, fisika dan juga kandungan Klorofil-A. Pengukuran kandungan klorofil-a fitoplankton merupakan salah satu alat pengukuran kesuburan suatu perairan. Klorofil-a fitoplankton adalah suatu pigmen aktif dalam sel tumbuhan yang mempunyai peran penting dalam berlangsungnya proses fotosintesis perairan. Penelitian dilakukan pada bulan April – Mei 2013 di Sungai Wedung, Demak bertujuan untuk mengetahui aktivitas manusia terhadap sebaran klorofil-a, keterkaitan antara klorofil-a dan kelimpahan fitoplankton dan tingkat kesuburan perairan berdasarkan kandungan klorofil-a fitoplankton. Metode yang digunakan adalah metode studi kasus dengan teknik pengambilan sampel menggunakan metode “Sample Survey Method”. Hasil penelitian menunjukkan bahwa hasil analisis data klorofil menggunakan metode anova tersarang (nested anova) diperoleh nilai P untuk stasiun cukup besar sehingga tidak memberikan perbedaan yang nyata pada taraf kepercayaan 95 %. Akan tetapi perbedaan akan nyata pada taraf 90%. Hubungan antara klorofil-a dengan kelimpahan fitoplankton secara linear menunjukkan nilai keeratan yang tinggi dengan nilai koefisien korelasi sebesar 0,93 dan koefisien determinasi sebesar 0,8633 dimana 86% klorofil-a dipengaruhi oleh kelimpahan fitoplankton. Berdasarkan nilai rata-rata klorofil-a yang diperoleh sebesar 1,039863 mg/l dapat disimpulkan bahwa perairan Sungai Wedung tergolong kedalam perairan yang bersifat oligotrofik
Contemporaneous Portal-Arterial Reperfusion during Liver Transplantation: Preliminary Results
We prospectively compared sequential portal-arterial revascularization (SPAr, group 1 no. 19) versus contemporaneous portal-hepatic artery revascularization (CPAr, group 2 no. 21) in 40 consecutive liver transplantation (LT). There were no differences in the demographics characteristics, MELD score, indication to LT, and donor's parameters between the two groups. CPAr had longer warm ischemia 66 ± 8 versus 37 ± 7 min (P < .001), while SPAr had longer arterial ischemia 103 ± 42 min (P = .0004). One-year patient's and graft survival were, respectively, 89% and 95% versus 94% and 100% (P = .29). At median followup of 13 ± 6 versus 14 ± 7 months biliary complications were anastomotic stenosis in 15% versus 19% (P = .78), and intrahepatic nonanastomotic biliary strictures in 26% versus none (P = .01), respectively, in SPAr and CPAr. CPAr reduces the incidence of intrahepatic biliary strictures by decreasing the duration of arterial ischemia
Biological Compost Stability Influences Odor Molecules Production Measured by Electronic Nose During Food-Waste High-Rate Composting
Composting is a technique that is used to convert organic waste into agriculturally useful products. Composting is an aerobic, solid-state biological process, which typically can be divided into two phases, a high-rate composting phase and a curing phase. High-rate composting plays an important role during the composting process, owing to the high microbial activity occurring during this phase. It requires an accurate plant design to prevent the formation of anaerobic conditions and odors. The formation of anaerobic conditions mainly depends on the rate of O2 consumption needed to degrade the substrate, i.e., the biological stability of the substrate. In this study, we investigated the relationship between the biological activity, measured by the dynamic respiration index (DRI) and the odor molecules production, measured by an electronic nose (EN) during two food-waste high-rate composting processes. Although the O2 concentration in the biomass free air space (FAS) was kept optimal (O2 > 140\ua0ml l- 1, v/v) during composting, strong anaerobic conditions developed. This was indicated by the high levels of sulfur compounds, methane, and hydrogen in the outlet air stream. Both the high level of O2 consumption, needed to degrade the high-degradable water-soluble organic matter and the low water O2 solubility, caused by high temperature reached in this stage (up to 60\ua0\ub0C), led to the anaerobic conditions observed in the biofilm-particle level. The application of the partial least square (PLS) analysis demonstrated a good regression between the DRI and the odor molecules produced that was detected by the EN (R2 = 0.991; R2CV = 0.990), signifying the usefulness of the DRI as a parameter to estimate the potential production of odor molecules of the biomass
Age-specific prevalence of the different clinical presentations of AD and FTD in young-onset dementia
Background Studies have shown that the prevalence of all-variants Alzheimer's disease (AD) and frontotemporal dementia (FTD) both increase with age, even before the age of 65. However, it is not known whether their different clinical presentations all increase in prevalence with age in the same way.Methods We studied the prevalence of the different clinical presentations of young-onset AD and FTD by 5-year age groups in a population-based study identifying all dementia patients with a diagnosis of AD and FTD and symptoms onset before age 65 in the Modena province, Italy. By using regression models of cumulative occurrences, we also estimated age-specific prevalence and compared the growth curves of the clinical presentations.Results The prevalence of all-variants AD increased with age, from 18/1,000,000 in the 40-44 age group to 1411/1,000,000 in the 60-64 age group. The prevalence of all-variants FTD also increased with age, from 18/1,000,000 to 866/1,000,000. An estimation of age-specific prevalence functions of each clinical presentation showed that atypical non-amnestic AD and aphasic FTD grew the most in early ages, followed by the behavioural variant of FTD (bvFTD). Then, around the age of 60, amnestic AD took over and its age-specific prevalence continued to increase disproportionally compared to all the other clinical variants of AD and FTD, which, instead, started to decrease in prevalence.Conclusions Amnestic AD is the clinical presentation that increases the most with advancing age, followed by bvFTD, suggesting that there is a differential vulnerability to the effect of ageing within the same neurodegenerative disease
Environmental and occupational risk factors for early onset dementia in an Italian community
Background: Early onset dementia (EOD) is defined as dementia with symptoms onset before 65 years. Little is known about the etiological role of environmental and occupational risk factors. We aimed at assessing the role of these factors in disease etiology.Methods: Using a case-control design, we recruited all EOD cases resident in Modena province from October, 2016 to October, 2019, as well as a referent population drawn from patients’ care-givers. We investigated residential history of study participants, and their occupational and environmental exposures to pesticides, solvents and metals through a self-administered questionnaire. We computed the odds ratios (ORs) of disease risk, and the corresponding 95% confidence intervals (CIs), according to exposure to the investigated risk factors, using an unconditional logistic regression model adjusted for sex, age, and education. Results: Fifty-eight EOD cases and fifty-four controls agreed to participate. Among occupational factors, disease risk was associated with exposure to aluminum (OR 2.6, 95% CI 0.4-15.7), pesticides (OR 2.3, 95% CI 0.7-7.8) particularly from agricultural occupational exposure (OR 3.1, 95% CI 0.7-13.3) and dyes, paints or thinners (OR 1.7, 95% CI 0.6-5.0). Among lifestyles factors, smoking (OR 1.3, 95% CI 0.6-2.9) and playing football (OR 2.2, 95% CI 0.5-9.3) or cycling (OR 2.3, 95% CI 0.4-13.4) were associated with higher EOD risk, although overall sports practice appeared to be protective factor (OR 0.4, 95% CI 0.2-0.9). Risk was also positively associated with history of head trauma (OR 1.2, 95% CI 0.3-4.1) and particularly upper arm trauma (OR 2.2, 95% CI 0.7-7.5), but not overall trauma. No association emerged for exposure to electromagnetic fields. Conclusions:Despite the study limitations, our results appear to support a role of environmental risk factors in EOD etiology, particularly of some chemical exposures and professional sports, while overall sports practice may have a beneficial effect
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