109 research outputs found
Determining specific biomass activity in anaerobic wastewater treatment processes
«Erworben im Rahmen der Schweizer Nationallizenzen (http://www.nationallizenzen.ch)»An experimental method for the measurement of specific gas production rate was developed and tested with biomass samples taken from anaerobic fluidized bed reactors, operating with a variety of carriers with molasses, condensate from cellulose production and brewery wastewater as feeds. The method is based on reactor sampling and offline gas volume measurement during a known time interval. Important factors are biomass and liquid sampling under oxygen-free conditions, using the liquid from the reactor as substrate, providing sufficient mixing and maintaining the physical integrity of the biomass. The method was developed in such a way that small samples (20 ml) were taken under anaerobic conditions (poising agent) for short-term (2-3 min.) gas rate measurements in a small fluidized bed (25 ml) batch reactor with U-tube. Biomass content was measured by an instrumental nitrogen method (Dumas), followed by weight determination of the carrier. The gas rates measured with the test system, and their dependence on substrate concentration, were in good agreement with those directly measured from the continuous fluidized bed reactor. Additions of molasses and acetate to the sample proved that the influence of concentration on the biomass activity can be obtained only by operating the continuous reactor at the concentration levels of interest. Comparison between the reactors showed large differences in the specific activity and the total reactor activity. It was found when comparing two reactors, that the values of the specific and the total activities permitted the calculation of the relative biomass quantities. In this way the influence of the carrier-type could be evaluated
Phenol degradation in a three-phase biofilm fluidized sand bed reactor
«Erworben im Rahmen der Schweizer Nationallizenzen (http://www.nationallizenzen.ch)»A previous three phase fluidized sand bed reactor design was improved by adding a draft tube to improve fluidization and submerged effluent tubes for sand separation. The changes had little influence on the oxygen transfer coefficients(KL a), but greatly reduced the aeration rate required for sand suspension. The resulting 12.5 dm3 reactor was operated with 1 h liquid residence time, 10.2dm3/min aeration rate, and 1.7-2.3 kg sand (0.25-0.35 mm diameter) for the degradation of phenol as sole carbon source. The KLa of 0.015 s−1 gave more than adequate oxygen transfer to support rates of 180g phenol/h · m3 and 216 g oxygen/h · m3. The biomass-sand ratios of 20-35 mg volatiles/g gave estimated biomass concentrations of 3-6 g volatiles/dm3. Offline kinetic measurements showed weak inhibition kinetics with constants ofKs=0.2 mg phenol/dm3, Ko2=0.5 mg oxygen/dm3 and KinI= 122.5 mg phenol/dm3. Very small biofilm diffusion effects were observed. Dynamic experiments demonstrated rapid response of dissolved oxygen to phenol changes below the inhibition level. Experimentally simulated continuous stagewise operation required three stages, each with 1 h residence time, for complete degradation of 300 mg phenol/dm3 · h
α-Synuclein Aggregated with Tau and β-Amyloid in Human Platelets from Healthy Subjects: Correlation with Physical Exercise
The loss of protein homeostasis that has been associated with aging leads to altered levels and conformational instability of proteins, which tend to form toxic aggregates. In particular, brain aging presents characteristic patterns of misfolded oligomers, primarily constituted of β-amyloid (Aβ), tau, and α-synuclein (α-syn), which can accumulate in neuronal membranes or extracellular compartments. Such aging-related proteins can also reach peripheral compartments, thus suggesting the possibility to monitor their accumulation in more accessible fluids. In this respect, we have demonstrated that α-syn forms detectable hetero-aggregates with Aβ or tau in red blood cells (RBCs) of healthy subjects. In particular, α-syn levels and its heteromeric interactions are modulated by plasma antioxidant capability (AOC), which increases in turn with physical activity. In order to understand if a specific distribution of misfolded proteins can occur in other blood cells, a cohort of human subjects was enrolled to establish a correlation among AOC, the level of physical exercise and the concentrations of aging-related proteins in platelets. The healthy subjects were divided depending on their level of physical exercise (i.e., athletes and sedentary subjects) and their age (young and older subjects). Herein, aging-related proteins (i.e., α-syn, tau and Aβ) were confirmed to be present in human platelets. Among such proteins, platelet tau concentration was demonstrated to decrease in athletes, while α-syn and Aβ did not correlate with physical exercise. For the first time, α-syn was shown to directly interact with Aβ and tau in platelets, forming detectable hetero-complexes. Interestingly, α-syn interaction with tau was inversely related to plasma AOC and to the level of physical activity. These results suggested that α-syn heterocomplexes, particularly with tau, could represent novel indicators to monitor aging-related proteins in platelets
Long-term changes in population size and the age-structure and sex-ratio of Waterbuck in a Sudanian savannah of Burkina Faso
The waterbuck (Kobus ellipsiprymnus), though widespread throughout Africa, is suspected to be declining overall. Data on population numbers and structure are lacking for many parts of its range, especially in West Africa, where the subspecies defassa is found. The aim of the present study was to evaluate the abundance, distribution and attributes of waterbuck populations in the Nazinga Forest Reserve, southern Burkina Faso. We investigated waterbuck population trends in the park using transect data collected in 1985-2019. For the more detailed analyses of population structure and distribution of the animals we used census data gathered during 2019. Most animals were adults (46.6%), and the sex ratio was heavily skewed towards females (5:1). Most animals were concentrated along the larger rivers. There was no influence of poacher activity on waterbuck distribution. In the long term (1985-2019), the population dynamics of waterbuck can be roughly divided into two main periods: a phase of population increase from 1985 to 2005, and one of ongoing population collapse from 2007-2019 Although the declining population trend was obvious, coefficients of determination were low indicating that the years explained poorly the number of individuals and the number of sightings obtained. Waterbuck numbers in the Nazinga Forest Reserve are declining, but we found no single reason to explain this trend. It is likely that a combination of factors, including global warming (increased aridity) and illegal activities such as poaching, are responsible. Because there are probably multiple reasons for the observed waterbuck population decline in our study area, we suggest that a multifaceted approach should be adopted in order to enhance the conservation status of the local waterbuck populations
Nusinersen treatment and cerebrospinal fluid neurofilaments : An explorative study on Spinal Muscular Atrophy type 3 patients
The antisense oligonucleotide Nusinersen has been recently licensed to treat spinal muscular atrophy (SMA). Since SMA type 3 is characterized by variable phenotype and milder progression, biomarkers of early treatment response are urgently needed. We investigated the cerebrospinal fluid (CSF) concentration of neurofilaments in SMA type 3 patients treated with Nusinersen as a potential biomarker of treatment efficacy. The concentration of phosphorylated neurofilaments heavy chain (pNfH) and light chain (NfL) in the CSF of SMA type 3 patients was evaluated before and after six months since the first Nusinersen administration, performed with commercially available enzyme-linked immunosorbent assay (ELISA) kits. Clinical evaluation of SMA patients was performed with standardized motor function scales. Baseline neurofilament levels in patients were comparable to controls, but significantly decreased after six months of treatment, while motor functions were only marginally ameliorated. No significant correlation was observed between the change in motor functions and that of neurofilaments over time. The reduction of neurofilament levels suggests a possible early biochemical effect of treatment on axonal degeneration, which may precede changes in motor performance. Our study mandates further investigations to assess neurofilaments as a marker of treatment response
Nesting trees used by a pest bird (Village Weaver, Ploceus cucullatus): a large field survey suggests further human conflicts with local stakeholders in Southern Nigeria
The village weaver (Ploceus cucullatus) is a common colonial nesting bird widespread throughout Sub-Saharan Africa. It is known to weave its nests from leaf strips from a variety of tree species (mainly coconuts trees, oil palm trees) associated with human settlement areas, grasses, and other available plants. In this regard, this bird was considered a pest for its impact on different economic activities. Although extensive literature is already available on the parasitic role of village weavers, there is still a lack of analytical data that outlines which tree species are used for nesting and in what proportion, as well as the related implications in terms of economic impacts. Here, we carried out the first comprehensive arrangement of trees used by this species for nesting in Southern Nigeria (West Africa), checking for possible different impacts on stakeholders. In April 2021, we searched for village weaver nesting in 95 sites in 77 communities from 24 local government areas in Southern Nigeria, during 14 field surveys. Within each site, we collected GPS coordinates and counted the number of active nests, nesting birds and occupied trees. We recorded a total of 5,776 nests and 2,140 birds in 94 plants belonging to 23 tree species selected for nesting. Oil palm (Elaeis guineensis; n = 45) was the most used tree species, as 2,990 (51.77%) nests and 873 (40.79%) birds were recorded. Our results indicate the preference for nesting on trees used by stakeholders belonging to agricultural (palm farmers), touristic (operators) and energy (gas flare stations) sectors with economic implications about the conflict with this pest species
Evaluating the SERCA2 and VEGF mRNAs as Potential Molecular Biomarkers of the Onset and Progression in Huntington's Disease
Abnormalities of intracellular Ca2+ homeostasis and signalling as well as the down-regulation
of neurotrophic factors in several areas of the central nervous system and in peripheral
tissues are hallmarks of Huntington\u2019s disease (HD). As there is no therapy for this hereditary,
neurodegenerative fatal disease, further effort should be made to slow the progression
of neurodegeneration in patients through the definition of early therapeutic interventions.
For this purpose, molecular biomarker(s) for monitoring disease onset and/or progression
and response to treatment need to be identified. In the attempt to contribute to the research
of peripheral candidate biomarkers in HD, we adopted a multiplex real-time PCR approach
to analyse the mRNA level of targeted genes involved in the control of cellular calcium homeostasis
and in neuroprotection. For this purpose we recruited a total of 110 subjects possessing
the HD mutation at different clinical stages of the disease and 54 sex- and agematched
controls. This study provides evidence of reduced transcript levels of sarco-endoplasmic
reticulum-associated ATP2A2 calcium pump (SERCA2) and vascular endothelial
growth factor (VEGF) in peripheral blood mononuclear cells (PBMCs) of manifest and premanifest
HD subjects. Our results provide a potentially new candidate molecular biomarker
for monitoring the progression of this disease and contribute to understanding some early
events that might have a role in triggering cellular dysfunctions in HD
Evidence for Sub-Haplogroup H5 of Mitochondrial DNA as a Risk Factor for Late Onset Alzheimer's Disease
BACKGROUND: Alzheimer's Disease (AD) is the most common neurodegenerative disease and the leading cause of dementia among senile subjects. It has been proposed that AD can be caused by defects in mitochondrial oxidative phosphorylation. Given the fundamental contribution of the mitochondrial genome (mtDNA) for the respiratory chain, there have been a number of studies investigating the association between mtDNA inherited variants and multifactorial diseases, however no general consensus has been reached yet on the correlation between mtDNA haplogroups and AD. METHODOLOGY/PRINCIPAL FINDINGS: We applied for the first time a high resolution analysis (sequencing of displacement loop and restriction analysis of specific markers in the coding region of mtDNA) to investigate the possible association between mtDNA-inherited sequence variation and AD in 936 AD patients and 776 cognitively assessed normal controls from central and northern Italy. Among over 40 mtDNA sub-haplogroups analysed, we found that sub-haplogroup H5 is a risk factor for AD (OR=1.85, 95% CI:1.04-3.23) in particular for females (OR=2.19, 95% CI:1.06-4.51) and independently from the APOE genotype. Multivariate logistic regression revealed an interaction between H5 and age. When the whole sample is considered, the H5a subgroup of molecules, harboring the 4336 transition in the tRNAGln gene, already associated to AD in early studies, was about threefold more represented in AD patients than in controls (2.0% vs 0.8%; p=0.031), and it might account for the increased frequency of H5 in AD patients (4.2% vs 2.3%). The complete re-sequencing of the 56 mtDNAs belonging to H5 revealed that AD patients showed a trend towards a higher number (p=0.052) of sporadic mutations in tRNA and rRNA genes when compared with controls. CONCLUSIONS: Our results indicate that high resolution analysis of inherited mtDNA sequence variation can help in identifying both ancient polymorphisms defining sub-haplogroups and the accumulation of sporadic mutations associated with complex traits such as AD
German evidence-based guidelines for the treatment of Psoriasis vulgaris (short version)
Psoriasis vulgaris is a common and chronic inflammatory skin disease which has the potential to significantly reduce the quality of life in severely affected patients. The incidence of psoriasis in Western industrialized countries ranges from 1.5 to 2%. Despite the large variety of treatment options available, patient surveys have revealed insufficient satisfaction with the efficacy of available treatments and a high rate of medication non-compliance. To optimize the treatment of psoriasis in Germany, the Deutsche Dermatologische Gesellschaft and the Berufsverband Deutscher Dermatologen (BVDD) have initiated a project to develop evidence-based guidelines for the management of psoriasis. The guidelines focus on induction therapy in cases of mild, moderate, and severe plaque-type psoriasis in adults. The short version of the guidelines reported here consist of a series of therapeutic recommendations that are based on a systematic literature search and subsequent discussion with experts in the field; they have been approved by a team of dermatology experts. In addition to the therapeutic recommendations provided in this short version, the full version of the guidelines includes information on contraindications, adverse events, drug interactions, practicality, and costs as well as detailed information on how best to apply the treatments described (for full version, please see Nast et al., JDDG, Suppl 2:S1–S126, 2006; or http://www.psoriasis-leitlinie.de)
Monitoring the quality of laboraties and the prevalence of resistance to antituberculosis drugs: Italy, 1998-2000
In 1998 a network of 20 regional tuberculosis (TB) laboratories (the Italian Multicentre Study on Resistance to Antituberculosis drugs (SMIRA) network) was established in Italy to implement proficiency testing and to monitor the prevalence of drug resistance nationwide. The network managed 30% of all TB cases reported in Italy each year. The aim of the present report is to describe: 1) the accuracy of drug-susceptibility testing in the network; 2) the prevalence of drug resistance for the period 1998-2000. Data were collected from the network laboratories. Sensitivity to streptomycin and ethambutol increased from the first survey (1998-1999) to the second survey (2000) from 87.7 to 91.9%. Specificity, predictive values for resistance and susceptibility, efficiency and reproducibility were consistent in both surveys. In previously untreated cases, the prevalence of multidrug-resistance was the same in both surveys (1.2%), while a slight decrease from the first to the second survey was observed for monoresistance to rifampicin (from 0.8 to 0.4%) and isoniazid (from 2.9 to 2%,). The significant association found between isoniazid resistance and immigration is a useful indicator for both clinicians managing individual tuberculosis cases and public health services planning control strategies
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