Intrinsic Functional Brain Architecture Derived from Graph Theoretical Analysis in the Human Fetus

The human brain undergoes dramatic maturational changes during late stages of fetal and early postnatal life. The importance of this period to the establishment of healthy neural connectivity is apparent in the high incidence of neural injury in preterm infants, in whom untimely exposure to ex-uterine factors interrupts neural connectivity. Though the relevance of this period to human neuroscience is apparent, little is known about functional neural networks in human fetal life. Here, we apply graph theoretical analysis to examine human fetal brain connectivity. Utilizing resting state functional magnetic resonance imaging (fMRI) data from 33 healthy human fetuses, 19 to 39 weeks gestational age (GA), our analyses reveal that the human fetal brain has modular organization and modules overlap functional systems observed postnatally. Age-related differences between younger (GA <31 weeks) and older (GA≥31 weeks) fetuses demonstrate that brain modularity decreases, and connectivity of the posterior cingulate to other brain networks becomes more negative, with advancing GA. By mimicking functional principles observed postnatally, these results support early emerging capacity for information processing in the human fetal brain. Current technical limitations, as well as the potential for fetal fMRI to one day produce major discoveries about fetal origins or antecedents of neural injury or disease are discussed.     

New Perspectives in the Renin-Angiotensin-Aldosterone System (RAAS) III: Endogenous Inhibition of Angiotensin Converting Enzyme (ACE) Provides Protection against Cardiovascular Diseases

ACE inhibitor drugs decrease mortality by up to one-fifth in cardiovascular patients. Surprisingly, there are reports dating back to 1979 suggesting the existence of endogenous ACE inhibitors. Here we investigated the clinical significance of this potential endogenous ACE inhibition.ACE concentration and activity was measured in patient''s serum samples (n = 151). ACE concentration was found to be in a wide range (47–288 ng/mL). ACE activity decreased with the increasing concentration of the serum albumin (HSA): ACE activity was 56±1 U/L in the presence of 2.4±0.3 mg/mL HSA, compared to 39±1 U/L in the presence of 12±1 mg/mL HSA (values are mean±SEM). Effects of the differences in ACE concentration were suppressed in human sera: patients with ACE DD genotype exhibited a 64% higher serum ACE concentration (range, 74–288 ng/mL, median, 155.2 ng/mL, n = 52) compared to patients with II genotype (range, 47–194 ng/mL, median, 94.5 ng/mL, n = 28) while the difference in ACE activities was only 32% (range, 27.3–59.8 U/L, median, 43.11 U/L, and range 15.6–55.4 U/L, median, 32.74 U/L, respectively) in the presence of 12±1 mg/mL HSA. No correlations were found between serum ACE concentration (or genotype) and cardiovascular diseases, in accordance with the proposed suppressed physiological ACE activities by HSA (concentration in the sera of these patients: 48.5±0.5 mg/mL) or other endogenous inhibitors.Main implications are that (1) physiological ACE activity can be stabilized at a low level by endogenous ACE inhibitors, such as HSA; (2) angiotensin II elimination may have a significant role in angiotensin II related pathologies.     

Fluorescently Labeled Methyl-Beta-Cyclodextrin Enters Intestinal Epithelial Caco-2 Cells by Fluid-Phase Endocytosis

Cyclodextrins are widely used excipients for increasing the bioavailability of poorly water-soluble drugs. Their effect on drug absorption in the gastrointestinal tract is explained by their solubility- and permeability-enhancement. The aims of this study were to investigate penetration properties of fluorescently labeled randomly methylated-beta-cyclodextrin (FITC-RAMEB) on Caco-2 cell layer and examine the cellular entry of cyclodextrins on intestinal cells. The permeability of FITC-RAMEB through Caco-2 monolayers was very limited. Using this compound in 0.05 mM concentration the permeability coefficient was 3.35±1.29×10⁻⁸ cm/s and its permeability did not change in the presence of 5 mM randomly methylated-beta-cyclodextrin. Despite of the low permeability, cellular accumulation of FITC-RAMEB in cytoplasmic vesicles was significant and showed strong time and concentration dependence, similar to the characteristics of the macropinocytosis marker Lucifer Yellow. The internalization process was fully inhibited at 0°C and it was drastically reduced at 37°C applying rottlerin, an inhibitor of macropinocytosis. Notably, FITC-RAMEB colocalized with the early endosome organizer Rab5a. These results have revealed that FITC-RAMEB is able to enter intestinal epithelial cells by fluid-phase endocytosis from the apical side. This mechanism can be an additional process which helps to overcome the intestinal barrier and contributes to the bioavailability enhancement of cyclodextrins.     

Therapeutic Vaccination with TNF-Kinoid in TNF Antagonist-Resistant Rheumatoid Arthritis: A Phase II Randomized,Controlled Clinical Trial

Objectives

Active immunization, or vaccination, with tumor necrosis factor (TNF)-Kinoid (TNF-K) is a novel approach to induce polyclonal anti-TNF antibodies in immune-mediated inflammatory diseases. This study was performed to transfer the proof of concept obtained in mice model of rheumatoid arthritis (RA) into human. We designed a pilot study to demonstrate the feasibility of therapeutic vaccination in RA.

Methods

This was a phase IIa, placebo-controlled, multicenter study in adults with RA who previously experienced secondary failure of TNF antagonists. Patients were immunized intramuscularly with 2 or 3 doses of placebo (n = 10) or 90 (n = 6), 180 (n = 12), or 360 µg TNF-K (n = 12). The primary objective was to identify the best dose and schedule based on anti-TNF antibody titers. Clinical symptoms and safety were assessed during 12 months and solicited reactions for 7 days after each injection.

Results

The highest anti-TNF antibody response was detected in patients immunized with 360 µg TNF-K and with 3 injections, although this difference was not significant with all other groups. Similar proportions of patients receiving TNF-K and placebo reported adverse events up to month 12. Serious adverse events were reported by 4 patients treated with TNF-K (13.3%) and 3 treated with placebo (30.0%), all unrelated to treatment. At month 12, DAS28-CRP, tender and swollen joint counts, and HAQ scores decreased significantly more in patients who exhibited anti-TNF antibody response than in patients who did not.

Conclusions

TNF-K therapeutic vaccination induced dose- and schedule-dependent anti-TNF antibodies in RA patients and was well tolerated. Patients who developed anti-TNF antibodies showed a trend toward clinical improvement. Although the most aggressive dose and schedule, i.e. 360 mg dose administered 3 times, did show a strong trend of higher antibody response, further studies are warranted to examine even higher and more frequent doses in order to establish the best conditions for clinical improvement.

Trial Registration

ClinicalTrials.gov NCT01040715     

A newly identified group of adolescents at “invisible” risk for psychopathology and suicidal behavior: findings from the SEYLE study

This study explored the prevalence of risk behaviors (excessive alcohol use, illegal drug use, heavy smoking, reduced sleep, overweight, underweight, sedentary behavior, high use of Internet/TV/videogames for reasons not related to school or work, and truancy), and their association with psychopathology and self‐destructive behaviors, in a sample of 12,395 adolescents recruited in randomly selected schools across 11 European countries. Latent class analysis identified three groups of adolescents: a low‐risk group (57.8%) including pupils with low or very low frequency of risk behaviors; a high‐risk group (13.2%) including pupils who scored high on all risk behaviors, and a third group (“invisible” risk, 29%) including pupils who were positive for high use of Internet/TV/videogames for reasons not related to school or work, sedentary behavior and reduced sleep. Pupils in the “invisible” risk group, compared with the high‐risk group, had a similar prevalence of suicidal thoughts (42.2% vs. 44%), anxiety (8% vs. 9.2%), subthreshold depression (33.2% vs. 34%) and depression (13.4% vs. 14.7%). The prevalence of suicide attempts was 5.9% in the “invisible” group, 10.1% in the high‐risk group and 1.7% in the low‐risk group. The prevalence of all risk behaviors increased with age and most of them were significantly more frequent among boys. Girls were significantly more likely to experience internalizing (emotional) psychiatric symptoms. The “invisible” group may represent an important new intervention target group for potentially reducing psychopathology and other untoward outcomes in adolescence, including suicidal behavior.     

Role of Rho/ROCK signaling in the interaction of melanoma cells with the blood–brain barrier

We have investigated the role of the Rho/ROCK signaling pathway in the interaction of metastatic melanoma cells with the brain endothelium. ROCK inhibition induced a shift of melanoma cells to the mesenchymal phenotype, increased the number of melanoma cells attached to the brain endothelium, and strengthened the adhesion force between melanoma and endothelial cells. Inhibition of ROCK raised the number of melanoma cells migrating through the brain endothelial monolayer and promoted the formation of parenchymal brain metastases in vivo. We have shown that inhibition of the Rho/ROCK pathway in melanoma, but not in brain endothelial cells, is responsible for this phenomenon. Our results indicate that the mesenchymal type of tumor cell movement is primordial in the transmigration of melanoma cells through the blood–brain barrier.     

Shoc2/Sur8 Protein Regulates Neurite Outgrowth

The Shoc2 protein has been implicated in the positive regulation of the Ras-ERK pathway by increasing the functional binding interaction between Ras and Raf, leading to increased ERK activity. Here we found that Shoc2 overexpression induced sustained ERK phosphorylation, notably in the case of EGF stimulation, and Shoc2 knockdown inhibited ERK activation. We demonstrate that ectopic overexpression of human Shoc2 in PC12 cells significantly promotes neurite extension in the presence of EGF, a stimulus that induces proliferation rather than differentiation in these cells. Finally, Shoc2 depletion reduces both NGF-induced neurite outgrowth and ERK activation in PC12 cells. Our data indicate that Shoc2 is essential to modulate the Ras-ERK signaling outcome in cell differentiation processes involved in neurite outgrowth.     

TT virus in Hungary: sequence heterogeneity and mixed infections

The majority of the viral hepatitis cases is caused by five hepatitis viruses (A,B,C,D,E). In 1997, TT virus was discovered. It was supposed that a number of the unknown hepatitis cases was caused by the TT virus. The aim of this study was to characterize TT viruses carried by healthy individuals and patients suffering from hepatitis of unknown origin in Hungary. TTV DNA was detected by seminested PCR with the commonly used N22 primers. Twenty of the 108 sera (18.5%) taken from healthy persons and 115 of the 228 sera (50.4%) of patients with hepatitis of unknown origin were found to be positive. The nucleotide sequences of 26 clones derived from 17 hepatitis patients and 15 clones from nine healthy persons were determined and a phylogenetic tree was constructed. Genotype 2 (group 1) was found to be the most frequent, but other group 1 genotypes (1, 6) and genotypes 8 and 17 of group 2 were also detected. Mixed TTV infections were found in eight cases (two healthy persons and six hepatitis patients). Variants belonging to the same group were carried in seven cases, and the presence of group 1 (genotype 2) and group 2 (genotype 8) TTV sequences were found in one single hepatitis patient.     

1,4-Benzodiazepine peripheral cholecystokinin (CCK-A) receptor agonists

A series of 1,4-benzodiazepines, N-1-substituted with an N-isopropyl-N-phenylacetamide moiety, was synthesized and screened for CCK-A agonist activity. In vitro agonist activity on isolated guinea pig gallbladder along with in vivo induction of satiety following intraperitoneal administration in a rat feeding assay was demonstrated.