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721.
Shifts in feeding habits are expected to occur during adaptation to cave life Doltchopoda cave crickets inhabit both natural and artificial caves showing differences in population size, fecundity, phenology and age structure Compared to artificial caves, typically holding a seasonal age structure, populations from natural caves maintain a constantly heterogeneous age structure Faecal content analysis of 605 individuals from 24 natural and artificial cave populations, enabled us to characterize their trophic niche and to investigate its variation The results of multivariate analyses and measures of niche breadth and niche overlap outlined differences in trophic resource exploitation between natural and artificial cave populations Seasonal variation in diet occurred in both types of caves, and it was greater in artificial cave populations However, within any season, differences in feeding habits between individuals were much greater in natural caves resulting in a wider heterogeneity in trophic resources exploitation. Such heterogeneity appears to be mainly due to differences in diet between individuals of different developmental stages In fact, in a sample of 15 populations we found a positive, statistical significant correlation between niche breadth and heterogeneity in age structure These data are discussed in a broader evolutionary context in order to understand the role of limited resources availability in shaping and maintaining heterogeneity in age structure of Dolichopoda populations  相似文献   
722.
The experiments reported here add further evidence in support of the view that sex steroids may influence the binding characteristics of brain opioid receptors. In particular, it has been shown that: (a) the number of μ-opioid receptors varies in the hypothalamus of regularly cycling female rats according to the different phases of the estrous cycle, which are characterized by fluctuations of circulating levels of sex steroids; (b) the number of μ-opioid receptors decreases in the hypothalamus and in the corpus striatum when ovariectomized rats are submitted to treatments with estradiol and progesterone able to induce a “positive” feedback effect on LH release. A treatment with estrogen alone able to induce a “negative” feedback effect on LH release brings about an increase of the number of μ-opioid receptors in the thalamus and in the hippocampus; (c) in addition to the μ-receptors, receptors of the delta type may also be involved in the control of gonadotropin secretion; recent results here presented indicate that a line of immortalized hypothalamic cells (GT1 cells), which synthesize and secrete LHRH, present δ opioid receptors on their membranes; these are apparently involved in the control of LHRH release from these cells.  相似文献   
723.
724.
Malignant pleural effusions (MPEs) could represent an excellent source to culture a wide variety of cancer cells from different donors. In this study, we set up culture conditions for cancer cells deriving from MPEs of several patients affected by the most frequent form of lung cancer, namely the subset of non small cell lung cancers (NSCLC) classified as Lung Adenocarcinomas (AdenoCa) which account for approximately 40% of lung cancer cases. AdenoCa malignant pleural effusions gave rise to in vitro cultures both in adherent and/or in spheroid conditions in almost all cases analyzed. We characterized in greater detail two samples which showed the most efficient propagation in vitro. In these samples we also compared gene profiles of spheroid vs adherent cultures and identified a set of differentially expressed genes. Finally we achieved efficient tumor engraftment in recipient NOD/SCID mice, also upon inoculation of small number of cells, thus suggesting indirectly the presence of tumor initiating cells.  相似文献   
725.

Background

Systemic sclerosis (SSc) is a complex autoimmune disease characterized by vascular alterations and autoimmune activation leading to widespread organ fibrosis. At the early stage of disease when organ involvement and extent of disease are emerging, mast cells may have some role, as implied by both symptoms and histologic evidence.

Case presentation

A female patient diagnosed with cutaneous mastocytosis experienced the onset of systemic sclerosis after 15 years followed by the switch of mastocytosis to the systemic phenotype. A literature review on the evidences related to mast-cells activation in systemic sclerosis is presented below.

Conclusions

For clinicians, more attention must be paid to the potential association between systemic sclerosis and cancer. This case suggests that a proliferative disease in the mast cell compartment—though representing a rare association—may not be completely unexpected in SSc and perhaps excess mast cell activity can serve a pathogenic role in promoting fibrotic disease.
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726.
It has been established that Hsp60 can accumulate in the cytosol in various pathological conditions, including cancer and chronic inflammatory diseases. Part or all of the cytosolic Hsp60 could be naïve, namely, bear the mitochondrial import signal (MIS), but neither the structure nor the in solution oligomeric organization of this cytosolic molecule has still been elucidated. Here we present a detailed study of the structure and self-organization of naïve cytosolic Hsp60 in solution. Results were obtained by different biophysical methods (light and X ray scattering, single molecule spectroscopy and hydrodynamics) that all together allowed us to assay a wide range of concentrations of Hsp60. We found that Naïve Hsp60 in aqueous solution is assembled in very stable heptamers and tetradecamers at all concentrations assayed, without any trace of monomer presence.  相似文献   
727.
Fish oil-derived n-3 polyunsaturated fatty acids (n-3 PUFAs) inhibit invasion of some tumor cell types in vitro and in vivo. The mechanisms underlying this activity are unclear. Here, we examined the capability of n-3 PUFA-docosahexaenoic acid (22:6n-3; DHA) to affect the invasiveness of human RT112 urinary bladder and PT45 pancreatic carcinoma cell lines in vitro and the mechanism underlying this activity; n-6 PUFA-arachidonic acid (20:4n-6; AA) served as control. We showed that, in contrast to AA, 25, 50 and 100 μM DHA significantly inhibited in a dose-dependent manner the invasion through Matrigel of both RT112 and PT45 cells. Then, we analyzed whether the serine proteinase granzyme B (GrB), originally known as cytotoxic molecule of lymphocytes and recently also characterized for its extracellular functions such as invasion promotion of bladder cancer cells, might be involved in the invasion inhibitory activity exerted by DHA. We demonstrated that, accordingly to RT112 bladder cancer cells, PT45 cells expressed GrB and GrB promoted their invasion, since stealth RNA interference-mediated down-regulation of GrB dramatically suppressed PT45 cell invasion. Notably, we also showed that, in contrast to AA, 25, 50 and 100 μM DHA induced a dose-dependent down-modulation of GrB expression in both RT112 and PT45 cells. In conclusion, DHA can reduce the invasive phenotype of bladder and pancreatic carcinoma cells, and we provide the first evidence for a possible causative role of GrB in DHA-induced inhibition of cancer cell invasion. The potential use of fish oil as adjuvant antibladder and antipancreatic cancer agent may be suggested.  相似文献   
728.

Background

In mid 2010, the 7-valent pneumococcal conjugate vaccine (PCV7) was replaced by the 13-valent conjugate vaccine (PCV13) for childhood immunization in Italy. Our objective in this study was to obtain a snapshot of pneumococcal carriage frequency, colonizing serotypes, and antibiotic resistance in healthy children in two Italian cities one year after PCV13 was introduced.

Methods

Nasopharyngeal swabs were obtained from 571 children aged 0-5 years from November 2011-April 2012. Pneumococcal isolates were serotyped and tested for antimicrobial susceptibility. Penicillin and/or erythromycin non-susceptible isolates were analyzed by Multi Locus Sequence Typing (MLST).

Results

Among the children examined, 81.2% had received at least one dose of PCV7 or PCV13 and 74.9% had completed the recommended vaccination schedule for their age. Among the latter, 57.3% of children had received PCV7, 27.1% PCV13, and 15.6% a combination of the two vaccines. The overall carriage rate was 32.9%, with children aged 6-35 months the most prone to pneumococcal colonization (6-23 months OR: 3.75; 95% CI: 2.19-6.43 and 24-35 months OR: 3.15, 95%CI: 2.36-4.22). A total of 184 pneumococcal isolates were serotyped and divided into PCV7 (5.4%), PCV13 (18.0%), and non-PCV13 (82.0%) serotypes. Serotypes 6C, 24F, and 19A were the most prevalent (10.3%, 8.6%, and 8.1%, respectively). The proportion of penicillin non-susceptible (MIC >0.6 mg/L) isolates was 30.9%, while 42.3% were erythromycin resistant. Non-PCV13 serotypes accounted for 75.4% and 70.8% of the penicillin and erythromycin non-susceptible isolates, respectively.

Conclusions

Our results revealed low rates of PCV7 and PCV13 serotypes in Italian children, potentially due to the effects of vaccination. As the use of PCV13 continues, its potential impact on vaccine serotypes such as 19A and cross-reactive serotypes such as 6C will be assessed, with this study providing a baseline for further analysis of surveillance isolates.  相似文献   
729.
Cultured fibroblasts from patients affected by Alzheimer's disease (AD) exhibited peculiar alterations of the enzyme transketolase (TK). Abnormalities (dubbed alkaline bands, ab ) consisted of enzyme forms having unusually high pI and were proposed as a marker of the disease in living patients. The mechanisms of TK- ab expression were investigated with the use of cysteine proteinase inhibitors and purified preparations of either rat liver or human cysteine proteinases. The cysteine proteinase inhibitors N-acetyl-leu-leu-norleucinal (ALLN), L-trans-Epoxy-succinyl-leucylamido(4-guanidino)butane (E-64), and egg white cystatin added to AD cells just prior to extraction abolished TK abnormalities. Moreover, 1 day incubation of AD cultures with either ALLN (10 μg/ml), NH4Cl (10 mM), or KCl (30 mM) prevented TK- ab generation, due, presumably, to an impairment of lysosomal functions. Isolated rat liver cysteine proteinases were able to degrade TK in normal extracts and reproduce the characteristic TK- ab of AD fibroblasts. Moreover, pure human cathepsin H was also shown to partially induce an Alzheimer-like TK pattern and cleave normal TK to a 35 kDa fragment as spontaneously occurring in AD fibroblasts. The explanation of mechanisms of TK- ab formation provided evidence for an underlying imbalance of proteolysis in AD fibroblasts due to a relative increase/derangement of the cysteine proteinases cathepsins which might be also involved in the reported abnormal processing of multiple cellular components. J. Cell. Physiol. 172:63–68, 1997. © 1997 Wiley-Liss, Inc.  相似文献   
730.
Cell wall components of fungi involved in induction of host immune response are predominantly proteins and glycoproteins, the latter being mainly mannoproteins (MP). In this study we analyse the interaction of the MP from Candida albicans (MP65) with dendritic cells (DC) and demonstrate that MP65 stimulates DC and induces the release of TNF-alpha, IL-6 and the activation of IL-12 gene, with maximal value 6 h post treatment. MP65 induces DC maturation by increasing costimulatory molecules and decreasing CD14 and FcgammaR molecule expression. The latter effect is partly mediated by toll-like receptor 2 (TLR2) and TLR4, and the MyD88-dependent pathway is involved in the process. MP65 enables DC to activate T cell response, its protein core is essential for induction of T cell activation, while its glycosylated portion primarily promotes cytokine production. The mechanisms involved in induction of protective response against C. albicans could be mediated by the MP65 antigen, suggesting that MP65 may be a suitable candidate vaccine.  相似文献   
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