469 research outputs found
Predator and detritivore niche width helps to explain biocomplexity of experimental detritus-based food webs in four aquatic and terrestrial ecosystems
In the study of food webs, the existence and explanation of recurring patterns, such as the scale
invariance of linkage density, predator–prey ratios and mean chain length, constitute long-standing
issues. Our study focused on litter-associated food webs and explored the influence of detritivore and
predator niche width (as d13C range) on web topological structure. To compare patterns within and
between aquatic and terrestrial ecosystems and take account of intra-habitat variability, we constructed
42 macroinvertebrate patch-scale webs in four different habitats (lake, lagoon, beech forest and
cornfield), using an experimental approach with litterbags. The results suggest that although web
differences exist between ecosystems, patterns are more similar within than between aquatic and
terrestrial web types. In accordance with optimal foraging theory, we found that the niche width of
predators and prey increased with the number of predators and prey taxa as a proportion of total taxa in
the community. The tendency was more marked in terrestrial ecosystems and can be explained by a
lower per capita food level than in aquatic ecosystems, particularly evident for predators. In accordance
with these results, the number of links increased with the number of species but with a significantly
sharper regression slope for terrestrial ecosystems. As a consequence, linkage density, which was found
to be directly correlated to niche width, increased with the total number of species in terrestrial webs,
whereas it did not change significantly in aquatic ones, where connectance scaled negatively with the
total number of species. In both types of ecosystem, web robustness to rare species removal increased
with connectance and the niche width of predators. In conclusion, although limited to litter-associated
macroinvertebrate assemblages, this study highlights structural differences and similarities between
aquatic and terrestrial detrital webs, providing field evidence of the central role of niche width in
determining the structure of detritus-based food webs and posing foraging optimisation constraints as a
general mechanistic explanation of food web complexity differences within and between ecosystem
types
Marked efficacy of Rituximab in multifocal motor neuropathy associated with chronic lymphocytic leukemia
The authors describe a patient who presented a multifocal motor neuropathy (MMN) associated with a high anti-ganglioside antibody (anti-GM1 and anti-GD1) titer at the clinical onset of a B-cell chronic lymphocytic leukemia (B-CLL). Immunomodulation (IVIg plus cyclosporine) resulted in a neurological improvement and reduced anti-ganglioside antibody titers, both of which remained stable for at least six years. After this period, the patient had a severe relapse of the neuropathy, which was independent of the clinical course of the B-CLL. Both IVIg and cyclophosphamide were ineffective, and the patient became tetraplegic within six months; in the meantime, the patient displayed an increased antiganglioside antibody titer. Treatment with rituximab (RTX), which is designed to selectively inhibit B cell function, resulted in a dramatic, prompt and long-lasting neurological improvement as well as a reduced anti-ganglioside antibody titer. Although there are no previous reports of MMN in patients with B-CLL, the efficacy of RTX in the treatment of MMN in this patient may be considered remarkable. The expansion of B-cell clones may be a prerequisite for RTX effectiveness in MMN, and in dysimmune neuropathies in general
Open Source Interactive Map of Albania Cultural Heritage
AbstractICTs represent strategic resources for Cultural Heritage (CH) projects. Anyway, several conditions put the success of promotion projects at risk, especially if carried out at the local level. Firstly, local scale amplifies the weight of budget constraints on the priorities of public administrations, compelled to allocate funds to the physical conservation of heritage rather than to software and training. Secondly, proprietary SW, often sophisticated and complex in procedures, fails to integrate precious unformalized knowledge from local stakeholders and communities, particularly in the field of cultural tourism. Finally, a changing demand for cultural tourism, with potential visitors frequently searching for information directly on the Web before moving, requires a higher interactivity in tools and systems. The paper illustrates the work carried out at the Construction Technologies Institute for delivering procedures and SW specifically designed to simplify the publication of geo-referenced information and reduce the need for specialized skills and equipments. The described results were achieved along different research programs focusing on the Albanian CH with a learning-by-doing approach
Marked efficacy of rituximab in multifocal motor neuropathy associated with chronic lymphocytic leukemia
The authors describe a patient who presented a multifocal motor neuropathy (MMN) associated with a
high anti-ganglioside antibody (anti-GM1 and anti-GD1) titer at the clinical onset of a B-cell chronic
lymphocytic leukemia (B-CLL). Immunomodulation (IVIg plus cyclosporine) resulted in a neurological
improvement and reduced anti-ganglioside antibody titers, both of which remained stable for at least six
years. After this period, the patient had a severe relapse of the neuropathy, which was independent of the
clinical course of the B-CLL. Both IVIg and cyclophosphamide were ineffective, and the patient became
tetraplegic within six months; in the meantime, the patient displayed an increased antiganglioside
antibody titer. Treatment with rituximab (RTX), which is designed to selectively inhibit B cell function,
resulted in a dramatic, prompt and long-lasting neurological improvement as well as a reduced antiganglioside
antibody titer. Although there are no previous reports of MMN in patients with B-CLL, the
eficacy of RTX in the treatment of MMN in this patient may be considered remarkable. The expansion of
B-cell clones may be a prerequisite for RTX effectiveness in MMN, and in dysimmune neuropathies in
general
HIV-1 induces in vivo platelet activation by enhancing platelet NOX2 activity.
OBJECTIVES: HIV-1 patients show increased platelet activation, but the mechanisms involved are not completely clarified. We speculated that HIV-1 might induce in vivo platelet activation by enhancing platelet NOX2-related oxidative stress. METHODS: We measured soluble CD40 Ligand (sCD40L), a systemic marker of platelet activation, in 36 HIV-1 patients under effective combined antiretroviral therapy (cART) and in 10 naïve HIV-1 subjects. As control, 20 healthy subjects (HS) were included. Platelet oxidative stress was measured by platelet NOX2-derived peptide (sNOX2-dp), p47(phox) translocation to platelet membrane and platelet prostaglandin F2α (8-iso-PGF2α). RESULTS: sCD40L was increased both in HIV-1 naïve and cART patients compared to HS (p < 0.001). Platelet sNOX2-dp and 8-iso-PGF2α were significantly higher in HIV-1 naïve subjects compared to those on cART and to HS, and both were mutually correlated (R = 0.734, p < 0.001). A stepwise multivariable linear regression analysis showed that platelet sNOX2-dp (β: 0.803, p < 0.001), HIV-1 infection (β: 0.146, p = 0.014) and age (β: 0.166, p = 0.001) were independently associated to sCD40L levels. CONCLUSIONS: HIV-1 infection is associated with increased platelet oxidative stress, which was related to the activation of NOX2. The independent association between platelet NOX2 activation and plasma levels of sCD40L suggest that in vivo platelet activation may be dependent upon platelet oxidative stress
Low concentrations of an nitric oxide-donor combined with a liposoluble antioxidant compound enhance protection against reperfusion injury in isolated rat hearts
Strategy for the treatment and follow-up of sinonasal solitary extramedullary plasmacytoma: a case series
Extramedullary plasmacytoma is a rare neoplasm characterized by monoclonal proliferation of plasma cells outside bone marrow. It accounts for 4% of all non-epithelial sinonasal tumors. According to the literature, radiotherapy is the standard therapy for extramedullary plasmacytoma. However, the conversion rate of extramedullary plasmacytoma to multiple myeloma is reported to be between 11 and 33% over 10 years. The highest risk of conversion is reported during the first 2 years after diagnosis, but conversion has been noted up to 15 years after diagnosis. Once conversion to multiple myeloma is complete, less than 10% of patients will survive 10 years
RELATIONSHIP BETWEEN POLYMORPHISMS OF TAS2R38 BITTER TASTE RECEPTOR AND CHRONIC UPPER AIRWAY INFECTIONS
1Department of Neuroscience, ENT Section, “Federico II” University of Naples, Italy
2Department of Translational Medical Sciences, European Laboratory for Food Induced Diseases, Napoli, Italy
The presence of taste receptors in extra-oral tissues may suggest additional roles apart from taste perception. Recently, an increasing number of reports demonstrated that the bitter taste G-protein coupled receptors family T2R, expressed in ciliated epithelial cells of the respiratory tract, are able to detect bacterial products and to stimulate innate immune defense against pathogens. Most microbial agents, secretes chemical signals known as quorum-sensing molecules that regulate the expression of genes involved in biofilm formation, virulence and other vital processes for microorganisms. Among the quorum-sensing molecules, the AHLs produced by P. aeruginosa, activate the receptor for bitter T2R38 expressed in ciliated epithelial cells of the respiratory tract, whereas mutants of P. aeruginosa lacking the AHL are not able to activate it. The activation of the receptor results in an increase of the Ca2+ flow and the ciliary beat frequency, as well as stimulating the production of NO which acts as a bactericide against the pathogen. The Caucasian population express three common polymorphisms (Pro49Ala, Ala262Val, Val296Ile) for TAS2R38 that lead to two major haplotypes PAV and AVI. The expression of either haplotype gives respectively 2 forms of receptors ̶ functional or non-functional ̶ i.e. unable to respond to specific agonists such phenylthiocarbamide and propylthiouracil (PROP). The two haplotypes PAV and AVI segregate into two major phenotypic classes: the "functional", sensitive to bitter, are homo- or heterozygous for the allele PAV, the "non-functional", are homozygous for the allele AVI. The genetic variations of the receptor TAS2R38 that affect sensitivity to bitter taste can help determine individual differences in susceptibility to bacterial infections of the respiratory tract allowing to plan a “target therapy”. Cellular cultures from homozygous PAV/PAV individuals showed a more effective NO production, mucociliary clearance and bactericide effect than cultures from AVI/PAV or AVI/AVI individuals. As a consequence it is reasonable to assume that patients with genotype AVI/PAV or AVI/AVI are at greater risk of contracting infections from gram-negative, compared with homozygous PAV. Some authors have studied the correlation between genotype and microbiological results TAS2R38 tissue of respiratory mucosa. The result of this analysis proved to be very interesting, because it showed a significant difference in the frequency of non-functional (AVI) than functional (PAV) among patients whose cultures were positive for Gram-negative bacteria, including P. aeruginosa.
The aim of the study was to characterize phenotypically the sensitivity to PROP and the receptor polymorphisms of TAS2R38, in patients with chronic or recurrent infections of the upper respiratory tract to identify high risk patients. The identification of high-risk individuals would allow to draw up protocols for specific follow-up and appropriate “target therapy”
Malondialdehyde in benign prostate hypertrophy: a useful marker?
Benign prostate hypertrophy (BPH) is the most common benign tumor in men due to obstruction of the urethra and, finally, uremia. Malondialdehyde (MDA) is a product derived from peroxidation of polyunsaturated fatty acids and related esters. Evaluation of MDA in serum represents a non-invasive biomarker of oxidative stress. Prostate-specific antigen (PSA) is a sensitive marker for prostatic hypertrophy and cancer. We analyzed MDA serum levels to evaluate the oxidative stress in BPH. To this end, 22 BPH patients and 22 healthy donors were enrolled. Data show an increase of MDA level in BPH patients and a positive correlation between PSA and MDA levels. In conclusion, we describe a previously unknown relationship between PSA and MDA as an index of inflammation and oxidative stress in BPH
Aphanizomenon flos-aquae (AFA) Extract Prevents Neurodegeneration in the HFD Mouse Model by Modulating Astrocytes and Microglia Activation
Obesity and related metabolic dysfunctions are associated with neurodegenerative diseases, such as Alzheimer's disease. Aphanizomenon flos-aquae (AFA) is a cyanobacterium considered a suitable supplement for its nutritional profile and beneficial properties. The potential neuroprotective effect of an AFA extract, commercialized as KlamExtra®, including the two AFA extracts Klamin® and AphaMax®, in High-Fat Diet (HFD)-fed mice was explored. Three groups of mice were provided with a standard diet (Lean), HFD or HFD supplemented with AFA extract (HFD + AFA) for 28 weeks. Metabolic parameters, brain insulin resistance, expression of apoptosis biomarkers, modulation of astrocytes and microglia activation markers, and Aβ deposition were analyzed and compared in the brains of different groups. AFA extract treatment attenuated HFD-induced neurodegeneration by reducing insulin resistance and loss of neurons. AFA supplementation improved the expression of synaptic proteins and reduced the HFD-induced astrocytes and microglia activation, and Aβ plaques accumulation. Together, these outcomes indicate that regular intake of AFA extract could benefit the metabolic and neuronal dysfunction caused by HFD, decreasing neuroinflammation and promoting Aβ plaques clearanc
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