Unraveling the parahormetic mechanism underlying the health-protecting effects of grapeseed procyanidins

Proanthocyanidins (PACs), the predominant constituents within Grape Seed Extract (GSE), are intricate compounds composed of interconnected flavan-3-ol units. Renowned for their health-affirming properties, PACs offer a shield against a spectrum of inflammation associated diseases, such as diabetes, obesity, degenerations and possibly cancer. While monomeric and dimeric PACs undergo some absorption within the gastrointestinal tract, their larger oligomeric and polymeric counterparts are not bioavailable. However, higher molecular weight PACs engage with the colonic microbiota, fostering the production of bioavailable metabolites that undergo metabolic processes, culminating in the emergence of bioactive agents capable of modulating physiological processes. Within this investigation, a GSE enriched with polymeric PACs was employed to explore in detail their impact. Through comprehensive analysis, the present study unequivocally verified the gastrointestinal-mediated transformation of medium to high molecular weight polymeric PACs, thereby establishing the bioaccessibility of a principal catabolite termed 5-(3',4'-dihydroxyphenyl)-γ-valerolactone (VL). Notably, our findings, encompassing cell biology, chemistry and proteomics, converge to the proposal of the notion of the capacity of VL to activate, upon oxidation to the corresponding quinone, the nuclear factor E2-related factor 2 (Nrf2) pathway-an intricate process that incites cellular defenses and mitigates stress-induced responses, such as a challenge brought by TNFα. This mechanistic paradigm seamlessly aligns with the concept of para-hormesis, ultimately orchestrating the resilience to stress and the preservation of cellular redox equilibrium and homeostasis as benchmarks of health.

Origin of dielectric polarization suppression in confined water from first principles

It has long been known that the dielectric constant of confined water should be different from that in bulk. Recent experiments have shown that it is vanishingly small, however the origin of the phenomenon remains unclear. Here we used ab initio molecular dynamics simulations (AIMD) and AIMD-trained machine-learning potentials to understand water's structure and electronic properties underpinning this effect. For the graphene and hexagonal boron-nitride substrates considered, we find that it originates in the spontaneous anti-parallel alignment of the water dipoles in the first two water layers near the solid interface. The interfacial layers exhibit net ferroelectric ordering, resulting in an overall anti-ferroelectric arrangement of confined water. Together with constrained hydrogen-bonding orientations, this leads to much reduced out-of-plane polarization. Furthermore, we directly contrast AIMD and simple classical force-field simulations, revealing important differences. This work offers insight into a property of water that is critical in modulating surface forces, the electric-double-layer formation and molecular solvation, and shows a way to compute it.

Rilpivirine plus cobicistat-boosted darunavir as a two-drug switch regimen in HIV-infected, virologically suppressed subjects on steady standard three-drug therapy: a randomized, controlled, non-inferiority trial (PROBE 2)

BACKGROUND

We explored the combination of rilpivirine plus cobicistat-boosted darunavir [a two-drug regimen (2DR)] when switching from standard triple combined ART.

METHODS

In this randomized, open-label, non-inferiority trial, participants had an HIV-RNA <50 copies/mL on a stable (>6 months) three-drug regimen. The primary endpoint was proportion with HIV-RNA <50 copies/mL at Week 24 (snapshot algorithm), with a -12% non-inferiority margin. ClinicalTrials.gov: NCT04064632.

RESULTS

One hundred and sixty patients were allocated (1:1) to 2DR or to continue current ART (CAR). At Week 24, 72 (90.0%) of participants with 2DR and 75 (93.8%) with CAR maintained HIV-RNA <50 copies/mL [difference -3.75% (95% CI = -11.63 to 5.63)], confirming non-inferiority. Non-inferiority was confirmed considering an HIV-RNA >50 copies/mL (0% for 2DR; 3.7% for CAR; 95% CI = -0.4 to 7.9). Four patients reported adverse events not leading to treatment discontinuation (one patient in the 2DR group and three patients in the CAR group); eight subjects discontinued therapy in the 2DR group and three in the CAR group. With 2DR, lipid serum concentrations increased, but differences were statistically significant only for tenofovir disoproxil fumarate-containing CAR and in 2DR patients receiving a pre-switch regimen including tenofovir disoproxil fumarate. Median bone stiffness decreased in the CAR group from 86.1 g/cm2 (IQR = 74-98) to 83.2 g/cm2 (IQR = 74-97) and increased in the 2DR group from 84.9 g/cm2 (IQR = 74-103) to 85.5 g/cm2 (IQR = 74-101). The reduction within the CAR group was significant (P = 0.043).

CONCLUSIONS

Once-daily rilpivirine plus cobicistat-boosted darunavir is an effective 2DR that combines a high virological efficacy with a potential to avoid major NRTI toxicities.

Novel compact hard x-ray spectrometer with MCps counting rate capabilities for runaway electron measurements on DIII-D

A novel compact spectrometer optimized for the measurement of hard x rays generated by runaway electrons is presented. The detector is designed to be installed in the fan-shaped collimator of the gamma-ray imager diagnostic at the DIII-D tokamak. The spectrometer is based on a 1 × 1 cm² cerium doped yttrium aluminum perovskite scintillator crystal coupled with a silicon photomultiplier. The detector dynamic energy range is in excess of 10 MeV, with an energy resolution of ∼10% at 661.7 keV. The fast detector signal (≈70 ns full width at half maximum) allows for operation at counting rates in excess of 1 MCps. The gain stability of the system can be monitored in real time using a light-emitting diode embedded in the instrument. The detector is expected to be deployed in the forthcoming DIII-D runaway electron experimental campaign.

Charge-polarized interfacial superlattices in marginally twisted hexagonal boron nitride

When two-dimensional crystals are brought into close proximity, their interaction results in reconstruction of electronic spectrum and crystal structure. Such reconstruction strongly depends on the twist angle between the crystals, which has received growing attention due to interesting electronic and optical properties that arise in graphene and transitional metal dichalcogenides. Here we study two insulating crystals of hexagonal boron nitride stacked at small twist angle. Using electrostatic force microscopy, we observe ferroelectric-like domains arranged in triangular superlattices with a large surface potential. The observation is attributed to interfacial elastic deformations that result in out-of-plane dipoles formed by pairs of boron and nitrogen atoms belonging to opposite interfacial surfaces. This creates a bilayer-thick ferroelectric with oppositely polarized (BN and NB) dipoles in neighbouring domains, in agreement with our modeling. These findings open up possibilities for designing van der Waals heterostructures and offer an alternative probe to study moiré-superlattice electrostatic potentials.

Groundwater and surface water quality characterization through positive matrix factorization combined with GIS approach

This study aims at testing the effectiveness of Positive Matrix Factorization in characterizing groundwater and surface water quality, in terms of identifying main hydrochemical features and processes (natural and anthropogenic) that govern them. This method is applied in a hydro-system featured by a strong interrelation between groundwater and surface water and highly impacted by agricultural activities. Therefore, a holistic approach considering groundwater together with the surface water bodies, consisting in lake, several rivers and springs, was used. Multivariate statistical analysis, in particular Factor Analysis, has been proved to be effective in elaborating and interpreting water quality data highlighting the information carried within them, but it presents some limitations: it does not consider data uncertainty and it groups variables which are correlated positively and negatively. Moreover, in some cases the resulting factors are not clearly interpretable, describing each one various overlapping features/processes. Here, Positive Matrix Factorization is applied to groundwater and surface water quality data, and the results are compared to those obtained through a Factor Analysis in terms of both factor profiles and their spatial distribution through a GIS approach. Results of isotopes analysis are used to validate PMF output and support interpretation. Positive Matrix Factorization allows to consider data uncertainty and the solution respects two positivity constraints, based on the concept of chemical mass balance, which leads to a more environmentally interpretable solution. Results show that Positive Matrix Factorization identifies five different factors reflecting main features and natural and anthropogenic processes affecting the study area: 1) surface water used for irrigation, 2) groundwater subjected to reducing processes at advanced stages, 3) groundwater subjected to reducing processes at early stages, 4) groundwater residence time and 5) the effects of the agricultural land use on both groundwater and surface water. Positive Matrix Factorization leads to a more detailed understanding of the studied system as compared to Factor Analysis which identifies only three factors with overlapping information. Based on the results of this study, Positive Matrix Factorization could be a useful technique to perform groundwater and surface water quality characterization and to reach a deeper understanding of the phenomena that govern water chemistry.

Anatomical variations of the median nerve and of the vascular-nervous structures at the wrist

Three cases of anatomical variation of the median nerve at the wrist found during our surgical activity led us to take the opportunity to expose anatomical variations by reviewing already published reviews. Consequently, on the basis of anatomical studies, clinical reports and imaging, as a result of careful examination of the published literature, it has been observed that the interventions in such anatomical area must take into account these variations. In particular, the most performed procedure is the lysis of the transverse carpal ligament (TCL), which is not free from complications. In our opinion it is therefore necessary, in order to avoid the complications of the nervous, vascular and tendinous sections, to use some specific technical procedures.

Anomalously low dielectric constant of confined water

The dielectric constant ε of interfacial water has been predicted to be smaller than that of bulk water (ε ≈ 80) because the rotational freedom of water dipoles is expected to decrease near surfaces, yet experimental evidence is lacking. We report local capacitance measurements for water confined between two atomically flat walls separated by various distances down to 1 nanometer. Our experiments reveal the presence of an interfacial layer with vanishingly small polarization such that its out-of-plane ε is only ~2. The electrically dead layer is found to be two to three molecules thick. These results provide much-needed feedback for theories describing water-mediated surface interactions and the behavior of interfacial water, and show a way to investigate the dielectric properties of other fluids and solids under extreme confinement.

Serum Levels of Insulin-Like Growth Factor-I in Operable Breast Cancer in Relation to the Main Prognostic Variables and their Perioperative Changes in Relation to those of Prolactin

Aims and background

In addition to estrogens, prolactin (PRL) and IGF-I have also appeared to stimulate breast cancer growth. The present study was performed to evaluate IGF-I blood levels in operable breast cancer in relation to PRL values and the main prognostic variables.

Methods

The study included 40 patients, clinical stage T1-3NO-2MO. Venous blood samples were collected before and 7 days after surgery. PRL and IGF-I were measured by radioimmunoassay. The control group consisted of 50 healthy women.

Results

Mean serum levels of IGF-I were significantly higher in patients than in controls, without any apparent relation to the main prognostic variables, including estrogen receptor and node status. Surgery-induced hyperprolactinemia occurred in 22/40 patients. IGF-I mean concentrations observed in the postoperative period in patients with surgery-induced hyperprolactinemia were significantly lower than those seen in patients showing no postoperative PRL rise.

Conclusions

The study showed that operable breast cancer may be associated with abnormally high levels of tumor growth factor IGF-I, and that surgery was followed by an IGF-I decline only in patients who showed surgery-induced hyperprolactinemia. Our previous studies have shown that postoperative hyperprolactinemia is a favorable prognostic factors for operable breast cancer. The present study, by showing that a postoperative PRL rise is associated with a fall in IGF-I, would suggest that surgery-induced hyperprolactinemia may determine a lower tumor relapse rate by determining a diminished secretion of breast tumor growth factor IGF-I.

Increased Blood Concentrations of Interleukin-12 are Associated with a Longer Survival in Untreatable Metastatic Solid Tumor Patients: Preliminary Observations

IL-2 and IL-12 are the main antitumor cytokines in humans. Endogenous IL-2 production is generally low in metastatic cancer patients. In contrast, preliminary data suggest a possible increased secretion of IL-12 in a subgroup of metastatic cancer patients, of which the prognostic significance is still to be established. This preliminary study was performed to investigate the survival time in relation to IL-12 blood levels in patients with untreatable metastatic solid tumors. The study included 40 patients (lung cancer: 16; gastrointestinal tumors: 24). Abnormally elevated serum levels of IL-12 were observed in 15/40 (37%) patients, without any apparent relation with tumor histotype. The 1-year survival rate was significantly higher in patients with elevated IL-12 baseline values than in those with normal concentrations (8/15 vs 3/25, p < 0.01). The results of this preliminary study, which need to be confirmed in a greater number of patients by monitoring the clinical course of the neoplastic disease, seem to suggest that abnormally high baseline serum levels of the antitumor cytokine IL-12 may have a favorable prognostic significance, as they appear to be associated with a longer survival time.

Changes in Circulating Dendritic Cells and IL-12 in Relation to the Angiogenic Factor VEGF during IL-2 Immunotherapy of Metastatic Renal Cell Cancer

Angiogenesis and immunosuppression are the main biological mechanisms responsible for cancer progression. Moreover, recent observations suggesting a negative influence of angiogenesis on anticancer immunity have shown that some angiogenic factors, such as VEGF, may induce immunosuppression. In addition, the evidence of abnormally high blood levels of VEGF has been proven to be associated with resistance to IL-2 immunotherapy. The present study was performed to establish a possible relation ship between the efficacy of IL-2 cancer immunotherapy and changes in circulating levels of VEGF, IL-12, mature and immature dendritic cells (DC). The study included 25 metastatic renal cell cancer patients who underwent subcutaneus low-dose IL-2 immunotherapy (6 MIU/day for 6 days/week for 4 weeks). Immature and mature DCs were identified as CD123+ and CD11c+ cells, respectively. The clinical response consisted of partial response (PR) in five, stable disease (SD) in 11 and progressive disease (PD) in the remaining nine patients. The mean IL-12 levels observed during IL-2 immunotherapy were significantly higher in patients with PR or SD than in those with PD, whereas the mean VEGF concentrations were significantly higher in patients who had PD than in those with PR or SD. Finally, a significant increase in the mean number of circulating mature DCs occurred only in patients with PR or SD, whereas no significant change was seen in patients with PD. By contrast, no significant change was observed in the mean number of immature DCs. This study shows that the efficacy of IL-2 immunotherapy is associated with a significant increase in circulating mature DCs and IL-12, without any concomitant increase in VEGF concentrations. Further studies will be required to better define the relationship between activation of anticancer immunity and control of angiogenesis-related mechanisms.

Vascular Endothelial Growth Factor (VEGF) Serum Levels during Cancer Immunotherapy with IL-2: Preliminary Considerations

Neoangiogenesis has been proven to play a fundamental role in promoting cancer spread, and vascular endothelial growth factor (VEGF) is known to represent one of the most important angiogenic factors. The present study was planned to investigate changes in VEGF secretion in cancer patients undergoing immunotherapy with IL-2, with the aim of establishing whether VEGF variations play a role in mediating the IL-2-induced control of neoplastic diseases. The study involved 14 metastatic renal cell cancer patients treated with IL-2 immunotherapy (6 million IU/day subcutaneously for 6 days/week for 4 weeks). The clinical response consisted of partial response (PR) in 3, stable disease (SD) in 6 and progressive disease (PD) in the remaining 5 patients. VEGF serum levels were measured by an enzyme immunoassay designed to determine both bound and unbound VEGF. No significant changes in VEGF mean levels occurred during IL-2 therapy. Moreover, neither in patients with PR or SD nor in those with PD did the mean serum levels of VEGF change significantly in response to IL-2. This preliminary study seems to exclude that changes in the angiogenic factor VEGF may play a role in mediating the therapeutic efficacy of IL-2 cancer immunotherapy. However, since the method of measurement used in our study was designed to detect the total amount of VEGF, it cannot be excluded that changes in the free fraction of the molecule may occur during IL-2 cancer immunotherapy.

Circulating Immature and Mature Dendritic Cells in Relation to Lymphocyte Subsets in Patients with Gastrointestinal Tract Cancer

Cancer-related deficiency in circulating dendritic cells (DC), whose important anticancer role is well established, has been proven to be associated with lymphocytopenia. This study was performed to evaluate which lymphocyte subset is most markedly related to the failure of the DC system. The study included 30 patients with gastrointestinal tract cancer, 10 of whom had distant organ metastases. Immature and mature DCs were measured by FACS and monoclonal antibodies against CD123 and CD11c antigens, respectively. Low levels of immature and mature DCs were observed in 63% and 43% of patients, respectively. Patients with low levels of circulating mature DCs had significantly lower values of T lymphocytes, T helper lymphocytes and NK cells than those with normal mature DC levels. In contrast, no significant difference was seen between patients with normal or abnormally low values of immature DCs. Conversely, patients with a decreased number of T lymphocytes, T helper lymphocytes and NK cells showed significantly lower values of circulating mature DCs than those with lymphocyte subsets within the normal range, whereas no difference was seen in immature DC amounts. This study suggests that only mature DC deficiency may be associated with important lymphocyte subset alterations in cancer patients, whereas deficiency in immature DCs does not seem to be related to other immune cell disorders.

Changes in Lymphocyte Number during Cancer Chemotherapy and Their Relation to Clinical Response

Since hematologic examination during cancer chemotherapy is generally limited to the evaluation of neutrophil and platelet numbers, at present there are no clear data about the possible prognostic significance of changes in lymphocyte number in relation to the clinical efficacy of chemotherapy itself. To obtain some preliminary data about this issue, we have evaluated changes in lymphocyte number and percentage in a group of 50 advanced non-small cell lung cancer patients treated with three cycles of cisplatin (20 mg/m2/day) plus etoposide (100 mg/m2/day) i.v for three days every 21 days. The clinical response consisted of partial response (PR) in nine (18%), stable disease (SD) in 18 (36%) and progressive disease (PD) in the remaining 23 (46%) patients. The lymphocyte percentage increased during chemotherapy, without, however, a significant difference with respect to the pretreatment values. In contrast, the mean number of lymphocytes observed after the first chemotherapeutic cycle significantly decreased in patients with PD, whereas it increased in patients with PR or SD, even though the difference did not reach statistical significance. These preliminary data, which have to be confirmed in a large number of patients and in patients treated with other chemotherapeutic schedules for different tumor types, seem to suggest that a chemotherapy-induced decline in lymphocyte number may be associated with a lack of efficacy of chemotherapy itself.

Changes in Circulating VEGF Levels in Relation to Clinical Response during Chemotherapy for Metastatic Cancer

Abnormally high blood levels of vascular endothelial growth factor (VEGF) appear to be associated with a poor prognosis in advanced cancer, probably as a consequence of its angiogenic and immunosuppressive effects. The prognostic significance of changes in VEGF secretion during cancer chemotherapy is still unknown. This study aimed to investigate the relation between VEGF variations and therapeutic results during chemotherapy in advanced malignancies. The study included 90 metastatic cancer patients, 59 with non-small cell lung cancer and 31 with colorectal carcinoma. Chemotherapy consisted of cisplatin plus etoposide for NSCLC and camptothecin for colorectal cancer. Abnormally high (>2 SD with respect to values in healthy controls) pretreatment VEGF levels were found in 38/90 (42%) patients. The percentage of non-progressive disease in response to chemotherapy was significantly higher in patients with normal levels of VEGF prior to therapy than in those with elevated pretreatment values of VEGF (10/32 vs 4/27; p<0.05). Moreover, the percentage of VEGF level normalization during chemotherapy was significantly higher in patients with objective tumor response or stable disease than in progressing patients (10/18 vs 0/20; p<0.001). Finally, among patients with tumor response or disease stabilization, the one-year survival rate was significantly higher in patients with chemotherapy-induced normalization of VEGF than in those with persistently high VEGF blood levels (9/10 vs 3/8; p<0.05). These results suggest that changes in VEGF levels during chemotherapy may represent a useful biomarker to predict the effect of chemotherapy in terms of tumor response and survival in patients with metastatic solid neoplasms.

Efficacy of Cancer Chemotherapy in Relation to the Pretreatment Number of Lymphocytes in Patients with Metastatic Solid Tumors

The evidence of lymphocytopenia has been demonstrated to predict a poor prognosis in terms of survival in advanced cancer patients. This finding is not surprising because of the fundamental role of lymphocytes in mediating tumor cell destruction. Despite the importance of lymphocytes in the pathogenesis of cancer, there are only few data about the profile and the function of lymphocytes during the various antitumor therapies, and in particular the relation between lymphocyte pretreatment number and response to chemotherapy remains to be established. The present study was performed to evaluate whether the evidence of lymphocytopenia before the onset of treatment may influence the efficacy of chemotherapy in metastatic cancer patients affected by the most frequent tumor types. The study included 183 patients (lung cancer: 89; colorectal cancer: 63; breast cancer: 31), 95 of whom had been previously treated with chemotherapy. The chemotherapeutic regimens consisted of oxaliplatin plus 5-fluorouracil and folates in untreated colorectal cancer, weekly irinotecan in pretreated colorectal cancer, cisplatin plus gemcitabine or etoposide in untreated lung cancer, weekly vinorelbine in pretreated lung cancer, and taxotere in breast cancer patients who had been previously treated with anthracyclines. Lymphocyte count was considered to be abnormally low for values below 1500/mm3. Lymphocytopenia was found in 79/183 (43%) patients, without any significant differences in relation to tumor histology. A complete response (CR) was achieved in 6/104 patients with a normal lymphocyte count and in none of the 79 lymphocytopenic patients. A partial response (PR) was obtained in 39 patients with a normal lymphocyte count and in only eight patients with a low lymphocyte count prior to therapy. Therefore, irrespective of the type of chemotherapy, the objective tumor response rate (CR + PR) in lymphocytopenic patients was significantly lower than in patients with normal pretreatment lymphocyte counts (8/79 vs 45/104; p<0. 001). This study shows that the evidence of lymphocytopenia prior to chemotherapy is associated with a lower efficacy of treatment in terms of objective tumor regression rates in patients with metastatic solid tumors, and suggests that the action of chemotherapy may depend at least in part on an interaction with the antitumor immunity. Pretreatment lymphocyte count may represent a new, simple biological marker to be taken into consideration by oncologists in the chemotherapeutic treatment of metastatic cancer.

Brain Irradiation-Induced Lymphocytosis Predicts Response in Cancer Patients with Brain Metastases

Lymphocytopenia is one of the main toxicities of radiotherapy and its severity is related to the irradiation dose. The occurrence of lymphocytopenia depends on the body site of radiotherapy; it is most pronounced with pelvic irradiation, whereas the effect of brain irradiation on the lymphocyte count is to be elucidated. This preliminary study was performed to evaluate changes in lymphocyte number occurring during brain irradiation in cancer patients with brain metastases. The study included 50 patients who received brain radiotherapy for single or multiple brain metastases at a total dose of 30 Gy. Overall, no significant changes in mean lymphocyte number occurred during brain radiotherapy. However, when lymphocyte variations were assessed in relation to the clinical response of brain metastases, a significant increase in the mean number of lymphocytes was found in patients who achieved objective regression of brain metastases on brain irradiation. The mean lymphocyte number decreased in nonresponding patients, albeit without a statistically significant difference with respect to the pretreatment values. The results of this study show that the efficacy of radiotherapy in the treatment of brain metastases is associated with a significant increase in mean lymphocyte number. Therefore, evidence of brain irradiation-induced lymphocytosis may predict the efficacy of radiotherapy.

Nanoscale dielectric microscopy of non-planar samples by lift-mode electrostatic force microscopy

Lift-mode electrostatic force microscopy (EFM) is one of the most convenient imaging modes to study the local dielectric properties of non-planar samples. Here we present the quantitative analysis of this imaging mode. We introduce a method to quantify and subtract the topographic crosstalk from the lift-mode EFM images, and a 3D numerical approach that allows for extracting the local dielectric constant with nanoscale spatial resolution free from topographic artifacts. We demonstrate this procedure by measuring the dielectric properties of micropatterned SiO2 pillars and of single bacteria cells, thus illustrating the wide applicability of our approach from materials science to biology.

Universal shape and pressure inside bubbles appearing in van der Waals heterostructures

Trapped substances between a two-dimensional (2D) crystal and an atomically flat substrate lead to the formation of bubbles. Their size, shape and internal pressure are determined by the competition between van der Waals attraction of the crystal to the substrate and the elastic energy needed to deform it, allowing to use bubbles to study elastic properties of 2D crystals and conditions of confinement. Using atomic force microscopy, we analysed a variety of bubbles formed by monolayers of graphene, boron nitride and MoS₂. Their shapes are found to exhibit universal scaling, in agreement with our analysis based on the theory of elasticity of membranes. We also measured the hydrostatic pressure induced by the confinement, which was found to reach tens of MPa inside submicron bubbles. This agrees with our theory estimates and suggests that for even smaller, sub-10 nm bubbles the pressure can be close to 1 GPa and may modify properties of a trapped material.

The interface between vertically stacked 2D materials can host contaminants trapped within bubbles. Here, the authors show that such nano-bubbles can be used as a platform to explore the van der Waals pressure and elasticity in atomically thin films, in a previously inaccessible confined environment.

Age-related ultrastructural and monoamine oxidase changes in the rat optic nerve

The aim of this paper is to study the morphology and the distribution of the monoamine oxidase enzymatic system in the optic nerve of 4 month-old Wistar (young) and 28 month-old Wistar (old) rats. The optic nerve was harvested from 20 young and old rats. The segment of optic nerve was divided longitudinally into two pieces, each 0.1 mm in length. The first piece was used for transmission electron microscopy. The second piece was stained with histochemical reaction for monoamine oxidase. The agerelated changes in the optic nerve of rats include micro-anatomical details, ultrastructure and monoamine oxidase histochemical staining. A strong decrease of the thin nerve fibers and a swelling of the thick ones can be observed in optic nerve fibers of old rats. Increased monoamine oxidase histochemical staining of the optic nerve of aged rats is well demonstrated. The increase of meningeal shealth and the decrease of thin nerve fibers of the optic nerve in old rats are well documented. Morphological, ultrastructural and histochemical changes observed in optic nerve fibers of the old rats show a close relation with aging.

Nanoscale electric polarizability of ultrathin biolayers on insulating substrates by electrostatic force microscopy

We measured and quantified the local electric polarization properties of ultrathin (∼5 nm) biolayers on mm-thick mica substrates. We achieved it by scanning a sharp conductive tip (<10 nm radius) of an electrostatic force microscope over the biolayers and quantifying sub-picoNewton electric polarization forces with a sharp-tip model implemented using finite-element numerical calculations. We obtained relative dielectric constants εr = 3.3, 2.4 and 1.9 for bacteriorhodopsin, dioleoylphosphatidylcholine (DOPC) and cholesterol layers, chosen as representative of the main cell membrane components, with an error below 10% and a spatial resolution down to ∼50 nm. The ability of using insulating substrates common in biophysics research, such as mica or glass, instead of metallic substrates, offers both a general platform to determine the dielectric properties of biolayers and a wider compatibility with other characterization techniques, such as optical microscopy. This opens up new possibilities for biolayer research at the nanoscale, including nanoscale label-free composition mapping.

Neurological soft signs in primary headache patients

Neurological soft signs (NSS) are semeiotic anomalies not assessed by the standard neurological examination, primarily developed in psychiatric settings and recently proposed as potential markers of minor brain circuit alterations, especially the cerebellar-thalamic-prefrontal network. Primary headache patients present with normal neurological examination and frequent psychiatric comorbidity. Aim of this exploratory study consisted in assessing NSS in 20 episodic frequent migraine (MH) and in 10 tension-type headache (ETTH) outpatients compared to 30 matched healthy controls. NSS were assessed by the Heidelberg scale; clinical characteristics and brain MRI were additionally obtained in all patients. NSS were increased by ∼70 and ∼90% in ETTH and MH, respectively, with respect to controls (p<0.001) and the difference remained significant even after controlling for age and education. Headache type and characteristics did not influence NSS presentation, while headache patients with white matter hyperintensities (WMH) at brain MRI had higher NSS scores compared both to normal controls and patients without WMH. NSS identify a subset of primary headache patients sharing the same comorbidities or minimal brain anomalies, suggesting that tailored prophylactic options might apply.

Quantitative electrostatic force microscopy with sharp silicon tips

Electrostatic force microscopy (EFM) probes are typically coated in either metal (radius ∼ 30 nm) or highly-doped diamond (radius ∼ 100 nm). Highly-doped silicon probes, which offer a sharpened and stable tip apex (radius ∼ 1-10 nm) and are usually used only in standard atomic force microscopy, have been recently shown to allow enhanced lateral resolution in quantitative EFM and its application for dielectric constant measurement. Here we present the theoretical modelling required to quantitatively interpret the electrostatic force between these sharpened tips and samples. In contrast to a sphere-capped cone geometry used to describe metal/diamond-coated tips, modelling a sharpened silicon tip requires a geometry comprised of a cone with two different angles. Theoretical results are supported by experimental measurements of metallic substrates and ∼10 nm radius dielectric nanoparticles. This work is equally applicable to EFM and other electrical scanned probe techniques, where it allows quantifying electrical properties of nanomaterials and 3D nano-objects with higher resolution.

Palmitoylethanolamide controls reactive gliosis and exerts neuroprotective functions in a rat model of Alzheimer's disease

Given the complex heterogeneity of pathological changes occurring in Alzheimer's disease (AD), any therapeutic effort absolutely requires a multi-targeted approach, because attempts addressing only a single event may result ineffective. Palmitoylethanolamide (PEA), a naturally occurring lipid amide between palmitic acid and ethanolamine, seems to be a compound able to fulfill the criteria of a multi-factorial therapeutic approach. Here, we describe the anti-inflammatory and neuroprotective activities of systemic administration of PEA in adult male rats given intrahippocampal injection of beta amyloid 1-42 (Aβ 1-42). Moreover, to investigate the molecular mechanisms responsible for the effects induced by PEA, we co-administered PEA with the GW6471, an antagonist of peroxisome proliferator-activated receptor-α (PPAR-α). We found that Aβ 1-42 infusion results in severe changes of biochemical markers related to reactive gliosis, amyloidogenesis, and tau protein hyperphosphorylation. Interestingly, PEA was able to restore the Aβ 1-42-induced alterations through PPAR-α involvement. In addition, results from the Morris water maze task highlighted a mild cognitive deficit during the reversal learning phase of the behavioral study. Similarly to the biochemical data, also mnestic deficits were reduced by PEA treatment. These data disclose novel findings about the therapeutic potential of PEA, and suggest novel strategies that hopefully could have the potential not just to alleviate the symptoms but also to modify disease progression.

Finite-size effects and analytical modeling of electrostatic force microscopy applied to dielectric films

A numerical analysis of the polarization force between a sharp conducting probe and a dielectric film of finite lateral dimensions on a metallic substrate is presented with the double objective of (i) determining the conditions under which the film can be approximated by a laterally infinite film and (ii) proposing an analytical model valid in this limit. We show that, for a given dielectric film, the critical diameter above which the film can be modeled as laterally infinite depends not only on the probe geometry, as expected, but mainly on the film thickness. In particular, for films with intermediate to large thicknesses (>100 nm), the critical diameter is nearly independent from the probe geometry and essentially depends on the film thickness and dielectric constant following a relatively simple phenomenological expression. For films that can be considered as laterally infinite, we propose a generalized analytical model valid in the thin-ultrathin limit (<20-50 nm) that reproduces the numerical calculations and the experimental data. Present results provide a general framework under which accurate quantification of electrostatic force microscopy measurements on dielectric films on metallic substrates can be achieved.

Calibrated complex impedance and permittivity measurements with scanning microwave microscopy

We present a procedure for calibrated complex impedance measurements and dielectric quantification with scanning microwave microscopy. The calibration procedure works in situ directly on the substrate with the specimen of interest and does not require any specific calibration sample. In the workflow tip-sample approach curves are used to extract calibrated complex impedance values and to convert measured S11 reflection signals into sample capacitance and resistance images. The dielectric constant of thin dielectric SiO2 films were determined from the capacitance images and approach curves using appropriate electrical tip-sample models and the εr value extracted at f = 19.81 GHz is in good agreement with the nominal value of εr ∼ 4. The capacitive and resistive material properties of a doped Si semiconductor sample were studied at different doping densities and tip-sample bias voltages. Following a simple serial model the capacitance-voltage spectroscopy curves are clearly related to the semiconductor depletion zone while the resistivity is rising with falling dopant density from 20 Ω to 20 kΩ. The proposed procedure of calibrated complex impedance measurements is simple and fast and the accuracy of the results is not affected by varying stray capacitances. It works for nanoscale samples on either fully dielectric or highly conductive substrates at frequencies between 1 and 20 GHz.

PCR-based isolation of multigene families: lessons from the avian MHC class IIB

The amount of sequence data available today highly facilitates the access to genes from many gene families. Primers amplifying the desired genes over a range of species are readily obtained by aligning conserved gene regions, and laborious gene isolation procedures can often be replaced by quicker PCR-based approaches. However, in the case of multigene families, PCR-based approaches bear the often ignored risk of incomplete isolation of family members. This problem is most prominent in gene families with highly variable and thus unpredictable number of gene copies among species, such as in the major histocompatibility complex (MHC). In this study, we (i) report new primers for the isolation of the MHC class IIB (MHCIIB) gene family in birds and (ii) share our experience with isolating MHCIIB genes from an unprecedented number of avian species from all over the avian phylogeny. We report important and usually underappreciated problems encountered during PCR-based multigene family isolation and provide a collection of measures to help significantly improving the chance of successfully isolating complete multigene families using PCR-based approaches.

Quantification of the dielectric constant of single non-spherical nanoparticles from polarization forces: eccentricity effects

We analyze by means of finite-element numerical calculations the polarization force between a sharp conducting tip and a non-spherical uncharged dielectric nanoparticle with the objective of quantifying its dielectric constant from electrostatic force microscopy (EFM) measurements. We show that for an oblate spheroid nanoparticle of given height the strength of the polarization force acting on the tip depends linearly on the eccentricity, e, of the nanoparticle in the small eccentricity and low dielectric constant regimes (1 < e < 2 and 1 < ε(r) < 10), while for higher eccentricities (e > 2) the dependence is sub-linear and finally becomes independent of e for very large eccentricities (e > 30). These results imply that a precise account of the nanoparticle shape is required to quantify EFM data and obtain the dielectric constants of non-spherical dielectric nanoparticles. Experimental results obtained on polystyrene, silicon dioxide and aluminum oxide nanoparticles and on single viruses are used to illustrate the main findings.

Theory of amplitude modulated electrostatic force microscopy for dielectric measurements in liquids at MHz frequencies

A theoretical analysis of amplitude modulated electrostatic force microscopy (AM-EFM) in liquid media at MHz frequencies, based on a simple tip-sample parallel plate model, is presented. The model qualitatively explains the main features of AM-EFM in liquid media and provides a simple explanation of how the measured electric forces are affected by: the frequency of the applied voltage, the tip-sample distance, the ionic concentration, the relative dielectric constant of the solution, and the relative dielectric constant and thickness of the sample. These results provide a simple framework for the design of AM-EFM measurements for localized dielectric characterization in liquid media.

Inflammatory Profile of Neurotrophins, IL-6, IL1-β, TNF-α, VEGF, ICAM-1 and TGF-β in the Human Waldeyer's Ring

The palatine tonsils, nasopharyngeal tonsil (adenoid) and lingual tonsil constitute the major part of Waldeyer's ring, with the tubal tonsils and lateral pharyngeal bands as less prominent components. The lymphoid tissue of Waldeyer's ring is located at the gateway of the respiratory and alimentary tract and belongs to the mucosa-associated lymphoid tissue (MALT). Mucosae-associated lymphoid tissues are richly innervated and the mucosae contain peptidergic nerve endings associated with different types of cells and macrophages. The lymphatic tissue is known to interact with the nervous system and several organs implicated in the host response to a wide range of stressors. This study focuses on the expression of some neurotrophins (NTs), their high- and low-affinity receptors in human adenoid tissues, lingual and palatine tonsils via immunohistochemical analysis, as well as on the expression of some inflammatory cytokines and other tissue growth factors. Light microscopy immunohistochemistry showed human samples to be generally positive for all the NTs investigated (NGF, BDNF, NT-3) and their receptors (TrKA, TrKB and TrKC) with some different expression levels. IL-6, IL1-b, TNF-α, VEGF, ICAM-1 and TGF-b were also investigated by immunohistochemistry. These results suggest the presence of a pattern of neurotrophic innervation in the human lymphatic tissues which may play a role in sustaining inflammatory conditions and in modulating a close interaction between the nervous system and the different immune cellular subtypes. Our data also corroborate previous studies, suggesting that neurotrophins and inflammatory cytokines may mediate functional signals in lymphoid aggregates. In this context, owing to their widespread expression in immune organs and immunocompetent cells, NTs and inflammatory cytokines are potential candidates for a prominent role in the regulation of immune and neuroimmune interactions.

Preoperative neuroimmunotherapy with subcutaneons low-dose interleukin-2 and melatonin in patients with gastrointestinal tumors - its efficacy in preventing surgery-induced lymphocytopenia

Our previous studies have shown that a preoperative injection of high dose IL-2 is able to abrogate surgery-induced immunosuppression in colorectal cancer patients. Moreover, our previous clinical investigations have indicated the possibility of amplifying IL-2 activity by a concomitant administration of the pineal immunomodulating hormone melatonin (MLT). On this basis, a biological study was performed to investigate the immune effects of a preoperative biotherapy consisting of low-dose IL-2 plus MLT in patients with gastrointestinal tumors. The study included 20 consecutive patients with gastrointestinal tract tumors, who underwent radical or palliative surgery. Patients were randomized to receive no preoperative treatment or a presurgical neuroimmunotherapeutic regimen consisting of low dose of IL-2 and MLT. IL-2 was injected subcutaneously at 3 million IU twice/day for 5 days in combination with MLT at 40 mg/day in the evening. Patients underwent surgery within 36 h from the last IL-2 injection. The mean number of lymphocytes, T lymphocytes and NK cells significantly decreased during the postoperative period in control patients, whereas it increased in patients pre-treated by immunotherapy. CD25-positive mean cell number increased in both groups of patients; however, postoperative mean number of CD25 expressing cells was significantly higher in patients pretreated with IL-2 and MLT than in controls. No immunotherapy-related toxicity occurred. This preliminary study would suggest that a neuroimmunotherapeutic regimen with low-dose IL-2 and MLT given preoperatively is a well tolerated therapy, which is able to prevent surgery-induced lymphocytopenia in cancer patients. This perioperative manipulation of host anticancer defenses could have a prognostic role in the clinical course of the neoplastic disease.

Tumour dormancy and clinical implications in breast cancer

The aim of adjuvant therapy in breast cancer is to reduce the risk of recurrence. Some patients develop metastases many years after apparently successful treatment of their primary cancer. Tumour dormancy may explain the long time between initial diagnosis and treatment of cancer, and occurrence of relapse. The regulation of the switch from clinical dormancy to cancer regrowth in locoregional and distant sites is poorly understood. In this review, we report some data supporting the existence of various factors that may explain cancer dormancy including genetic and epigenetic changes, angiogenic switch, microenvironment, and immunosurveillance. A better definition and understanding of these factors should allow the identification of patients at high risk of relapse and to develop new therapeutic strategies in order to improve prognosis.

Stroke care in young patients

The aims of this study were (i) to evaluate the clinical features of a consecutive series of young patients with ischemic stroke and (ii) to assess the changes in the clinical management of these patients over the study period. All consecutive cases of young adults aged 16 to 44 years, with ischemic stroke, that were admitted between 2000 and 2005 in 10 Italian hospitals were included. We retrospectively identified 324 patients. One or more vascular risk factors were present in 71.5% of the patients. With respect to the diagnostic process, an increase in the frequency of cerebral noninvasive angiographic studies and a decrease in the use of digital subtraction angiography were observed (P < 0.001 and P = 0.03, resp.). Undetermined causes decreased over 5-year period of study (P < 0.001). The diagnosis of cardioembolism increased. Thrombolysis was performed for 7.7% of the patients. PFO closure (8%) was the most frequently employed surgical procedure. In conclusion, the clinical care that is given to young patients with ischemic stroke changed over the study period. In particular, we detected an evolution in the diagnostic process and a reduction in the number of undetermined cases.

Infections occurring in adult patients receiving mechanical circulatory support: the two-year experience of an Italian National Referral Tertiary Care Center

OBJECTIVE

Infection during mechanical circulatory support is a frequent adverse complication. We analyzed infections occurring in this population in a national tertiary care center, and assessed the differences existing between the setting of extracorporeal membrane oxygenation (ECMO) and ventricular assist devices (VADs).

DESIGN, SETTING, AND PARTICIPANTS

An observational study was made of patients treated with ECMO or VAD in the San Raffaele Scientific Institute (Italy) between 2009 and 2011.

INTERVENTIONS

None.

RESULTS

Thirty-nine percent of the 46 patients with ECMO and 69% of the 15 patients with VAD developed infection. We observed a mortality rate of 36.1% during mechanical circulatory support and of 55.7% during the global hospitalization period. Although Gram-negative infections were predominant overall, patients with ECMO were more prone to develop Candida infection (29%), and patients with VAD tended to suffer Staphylococcus infection (18%). Patients with infection had longer ECMO support (p=0.03), VAD support (p=0.01), stay in the intensive care unit (p=0.002), and hospital admission (p=0.03) than patients without infection. Infection (regression coefficient=3.99, 95% CI 0.93-7.05, p=0.02), body mass index (regression coefficient=0.46, 95% CI 0.09-0.83, p=0.02), fungal infection (regression coefficient=4.96, 95% CI 1.42-8.44, p=0.009) and obesity (regression coefficient=10.47, 95% CI 1.77-19.17, p=0.02) were predictors of the duration of ECMO support. Stepwise logistic regression analysis showed the SOFA score at the time of implant (OR=12.33, 95% CI 1.15-132.36, p=0.04) and VAD (OR=1.27, 95% CI 1.04-1.56, p=0.02) to be associated with infection.

CONCLUSIONS

Infection is a major challenge during ECMO and VAD support. Each mechanical circulatory support configuration is associated with specific pathogens; fungal infections play a major role.

Efficacy and tolerability of cancer neuroimmunotherapy with subcutaneous low-dose interleukin-2 and the pineal hormone melatonin - a progress report of 200 patients with advanced solid neoplasms

The recent advances in psychoneuroimmunology have demonstrated the existence of a psychoneuroendocrine control of the antitumor immunity. Our previous preliminary studies indicated the possibility of amplifying the biological and therapeutic efficacy of IL-2 cancer immunotherapy by immunomodulating neurohormones, mainly the pineal indole melatonin (MLT), in most advanced solid tumors, including those which generally do not respond to IL-2 alone. This study reports on the results obtained by low-dose IL-2 plus MLT in 200 patients with advanced solid neoplasms, for whom no other effective standard therapy was available. Non-small cell lung cancer, pancreatic adenocarcinoma, hepatocarcinoma, colon cancer and gastric cancer were the neoplasms most frequently detected in our patients. In addition, all patients had a life expectancy less than 6 months. IL-2 was given subcutaneously at 3 million IU/day for 6 days/week for 4 weeks; MLT was given orally at 40 mg/day. In non-progressing patients, a second cycle was given after a 21-day rest period; then, patients underwent a maintenance period consisting of one week of therapy every month until progression. A complete response (CR) was achieved in 4 patients (hepatocarcinoma 2; pancreas 1; gastric cancer 1), a partial reasponse (PR) was achieved in 36 patients (lung 12; liver 6; stomach 4; pancreas 3; colon 3; breast 2; miscellaneous 6). Tumor response rate (CR+PR) was 40/200 (20%) patients. Longer than one year survival was achieved in 79 (39%) patients. Toxicity was mild in all patients, and therapy was administered as a home therapy. The present study confirms in a great number of patients the possibility to induce objective tumor regressions in most advanced solid tumor histotypes by low-dose IL-2 plus MLT. Thus, immunotherapy with IL-2 and MLT may be considered as a new well tolerated and effective therapy of almost all advanced solid tumors, including those which do not respond to IL-2 alone or to chemotherapy.

Surface AChE in the chick ciliary ganglion neurons: Ultrastructural localization and possible relations to ?-bungarotoxin receptors

The localization of acetylcholinesterase activity in the chick ciliary ganglion was investigated by ultrastructural cytochemistry. Both ganglionic cell populations, i.e. the ciliary and the choroid neurons, showed similar distribution patterns of the enzymic activity in the cytoplasm as well as at the neuronal surface. As indicated by specific inhibition tests, the whole enzymic activity was attributable to specific acetylcholinesterase. While the endocellular activity was mainly localized in the rough endoplasmic reticulum, the surface activity occurred at postsynaptic level and at extrasynaptic areas, where the neuronal membrane comes into contact with the plasma membrane of the satellite cell (boundary neuron-satellite cell). Enzymic activity also uniformly occurred at the surface of preganglionic nerve terminals. The surface localization of specific acetylcholinesterase recalls that recently described for ?-bungarotoxin receptors, which suggests that acetylcholinesterase and ?-bungarotoxin receptors can be distributed together, not only at postsynaptic level but also in extrasynaptic neuronal areas and at presynaptic level. The possibility that ?-bungarotoxin receptors and acetylcholinesterase form a .receptive' system not engaged in ganglionic transmission and not exclusively confined to postsynaptic level is discussed in relation to the electrophysiological data existing in literature.

Effects and Trimethyltin on Hippocampal Dopaminergic Markers and Cognitive Behaviour

The triorganotin compound trimethyltin (TMT) is a highly toxic molecule which has a great impact on human health. The aim of this study was to investigate the specific alteration of dopamine receptors and transporters in the hippocampus of TMT-treated rats. The TMT-treated group showed impaired spatial reference memory in a Morris water maze task compared to the control group, whereas memory consolidation tested 24 hours after the last training session was preserved. In the open field, TMT-treated rats showed a decrease in time spent in rearing episodes reflecting a lower interest to explore a novel environment. In the hippocampal area of the TMT-treated group, we observed a reduction in neuronal viability accompanied by a significant decrease in the expression of the dopamine receptors (D1 and D2), and dopamine transporters (DAT, VMAT1 and VMAT2). A less pronounced reduction was observed for D3 and D5 while D4 did not change. These data were confirmed by RT-PCR analysis. The present study on TMT-induced neurodegeneration highlights the link between hippocampal asset of dopamine receptors and transporters and the impaired performance of rats in a spatial reference memory task.

Immunohistochemical Profile and VEGF, TGF-β and PGE2 in Human Pterygium and Normal Conjunctiva: Experimental Study and Review of the Literature

Human pterygium is made up of chronic proliferative fibro-vascular tissue growing on the ocular surface. This disease exhibits both degenerative and hyperplastic properties. Some fibroangiogenic factors have recently been shown to play a potential role in fibrovascular diseases via the angiogenesis process. The aim of this study is to evaluate VEGF, TGF-β and PGE2 expression in the epithelial, endothelial and stromal cells of human pterygium and normal conjunctiva in order to determine whether these factors participate in the development of pterygium. Ten specimens from patients with pterygium and two normal conjunctivas (cadavers) were analyzed by immunohistochemistry using specific antibodies against these growth factors. The technique used was ABC/HRP (Avidin complexed with biotinylated peroxidase). Immunoreactivity of VEGF was significantly increased in the epithelium, vascular endothelium and stromal cells in primary pterygium as compared with normal conjunctiva. A moderate expression of TGF-β in the pterygium was observed in the epithelial and stromal layers. On the contrary, immunolabeling of this growth factor in the human normal conjunctiva was weak. PGE2 was strongly expressed in the epithelium of patients with pterygium, as in control conjunctival tissues, and the immunolabeling was moderate in the stroma from the same patients. Our results suggest that these growth factors may contribute to the progression of primary pterygium by increasing angiogenesis, thus leading to the formation of new blood vessels from the pre-existing vasculature. We conclude that VEGF, TGF-β and PGE2 may be potential therapeutic targets in the treatment of this disease although proof of this evidence requires further studies.