New Benzodihydrofuran Derivatives Alter the Amyloid β Peptide Aggregation: Strategies To Develop New Anti-Alzheimer Drugs

Alzheimer's disease is a neurodegenerative disorder that is the leading cause of dementia in elderly patients. Amyloid-β peptide (1-42 oligomers) has been identified as a neurotoxic factor, triggering many neuropathologic events. In this study, 15 chalcones were synthesized employing the Claisen-Schmidt condensation reaction, starting from a compound derived from fomannoxine, a natural benzodihydrofuran whose neuroprotective activity has been proven and reported, and methyl aromatic ketones with diverse patterns of halogenated substitution. As a result, chalcones were obtained, with good to excellent reaction yields from 50 to 98%. Cytotoxicity of the compounds was assessed, and their cytoprotective effect against the toxicity associated with Aβ was evaluated on PC-12 cells. Out of the 15 chalcones obtained, only the 4-bromo substituted was cytotoxic at most tested concentrations. Three synthesized chalcones showed a cytoprotective effect against Aβ toxicity (over 37%). The 2,4,5-trifluoro substituted chalcone was the most promising series since it showed a cytoprotective impact with more than 60 ± 5% of recovery of cellular viability; however, 3-fluoro substituted compound also exhibited important values of recovery (50 ± 6%). The fluorine substitution pattern was shown to be more effective for cytoprotective activity. Specifically, substitution with fluorine in the 3,5-positions turned out to be particularly effective for cytoprotection. Furthermore, fluorinated compounds inhibited the aggregation rate of Aβ, suggesting a dual effect that can be the starting point of new molecules with therapeutic potential.

Ugi and Passerini reactions enable the incorporation of ΔAA into N-alkylated peptides and depsipeptides

Isocyanide-based multicomponent reactions enable the incorporation of different dehydroamino acids under mild conditions.

Synthesis and Cytotoxic Analysis of Novel Myrtenyl Grafted Pseudo-Peptides Revealed Potential Candidates for Anticancer Therapy

Myrtenal is a natural monoterpene isolated from essential oils of several plants and their derivates have shown to have several biological properties including cytotoxicity. The cytotoxic activity of these derivates are being investigated for their antitumor effect leading to the development of potential anticancer agents. In this study, novels Myrtenyl grafted pseudo-peptides were designed, synthesized and functionally characterized as possible therapeutic agents for cancer treatment. Thirteen novel Myrtenyl grafted pseudo-peptides were prepared in high atom economy and efficiency by a classic Ugi-4CR and sequential post-modification. Their structures were confirmed by NMR, and ESI-MS, and its cytotoxic activity was evaluated in three cancer cell lines and primary CD4+ T cells at different proliferative cycles. Our results revealed that some of these compounds showed significant cytotoxicity against human gastric, breast and colon adenocarcinoma cells lines, but not against human dermal fibroblast cell line. Moreover, from the thirteen novel myrtenyl synthesized the compound (1R,5S)-N-{[1-(3-chlorophenyl)-1H-1,2,3-triazol-4-yl]methyl}-N-[2-(cyclohexylamino)-2–oxoethyl]-6,6-dimethylbicyclo[3.1.1]hept-2-ene-2-carboxamide (3b) proved to be the best candidate in terms of acceptable EC₅₀, and E_max values in cancer cell lines and at inducing cytotoxicity in CD4+ T cells undergoing active proliferation, without affecting non-proliferating T cells. Overall, the synthesis and characterization of our Myrtenyl derivates revealed novel potential anticancer candidates with selective cytotoxic activity.

Influence of counterions on the supramolecular frameworks of isoquinoline-based silver(i) complexes

Crystal structures of seven new Ag(i) complexes with bis(1-isoquinolinecarboxamide)alkane derivatives were analyzed in terms of the coordinative ability and participation in non-covalent interactions of several counterions.

A study of the cis–trans isomerization preference of N-alkylated peptides containing phosphorus in the side chain and backbone

The current work provides a study on the cis–trans isomerization behaviour of N-alkylated peptides decorated with phosphonate ester groups.

Profile of BAFF and its receptors' expression in lupus nephritis is associated with pathological classes

Background/Objective B-cell activating factor (BAFF) plays an important role in the pathogenesis of systemic lupus erythematosus. However, the role of BAFF in lupus nephritis (LN) is not understood. Our aim was to evaluate the expression of BAFF and its three receptors in renal biopsy samples from patients with LN and investigate a relationship with pathological class. Methods We conducted a prospective descriptive study (2011-2014) on 52 kidney biopsy samples from patients with LN. Immunohistochemistry for BAFF, its receptors (transmembrane activator and calcium modulator and cyclophilin ligand interaction (TACI), protein maturation of B cells (BCMA), and BAFF-receptor (BAFF-R)), and CD20 expression was performed. Samples were scored according to the percentage of cells with positive expression. Results In class II LN, BAFF-R and TACI were not expressed, whereas BCMA and BAFF were lowly expressed in the interstitial inflammatory infiltrates. Proliferative class III/IV had elevated BAFF expression in the glomeruli, and TACI was expressed in interstitial inflammatory infiltrates and the glomeruli. Interestingly, the class IV cases with vasculopathy ( n = 4) had endothelial BAFF expression, which was not visible in thrombotic microangiopathy ( n = 4). Class V was characterized by low BAFF expression in interstitial inflammatory infiltrates and by BAFF, TACI, and BCMA expression in the glomeruli. BAFF expression was associated with inflammatory scores and CD20 positive infiltrates, mainly in class IV. Conclusions Expression patterns of BAFF and its receptors differ according to LN class. Our study provides evidence that BAFF could be used as a routine marker in LN biopsies and to determine which patients will benefit from anti-BAFF therapy.

New anionic cobalt complexes using highly hindered bis-amides with varying donor abilities as ligands

Four potential tetradentate ligands of formulae 1,2-bis-(3,5-di-tert-butyl-2-hydroxybenzamido)ethane (H(4)L(1), 1), 1,2-bis-(3,5-di-tert-butyl-2-hydroxybenzamido)propane (H(4)L(2), 2), 1,2-bis-(3,5-di-tert-butyl-2-hydroxybenzamido)benzene (H(4)L(3), 3) and 1,8-bis-(3,5-di-tert-butyl-2-hydroxybenzamido)naphthalene (H(4)L(4), 4) have been prepared and the crystal structures of three of them (1, 3 and 4) determined by single crystal X-ray diffraction. The investigation of their complexing ability toward Co(II) afforded the compounds of formulae [Co(III)(L(3))Na(I)(H(2)O)(2)] (5), [Co(III)(L(n))Li(I)(H(2)O)2] with n = 1 (6), 2 (7) and 3 (8) and [Co(II)(L(4))Li(I)(2)] (9). Complexes 5-8 are square planar Co(III) species, as corroborated by the crystal structure of 5. In this compound, two amide-nitrogen and two phenolate-oxygen atoms of a fully deprotonated (L(3))(4-) anion build a slightly distorted square planar surrounding around the cobalt atom, the Co-N distances [1.858(3) and 1.861(3) A] being somewhat longer than the Co-O ones [1.798(3) and 1.801(3) A]. Magnetic and 1H NMR data at room temperature for 6-8 support the occurrence of an intermediate S = 1 low-lying state for the Co(III) center which is stabilized by the strong donating ability of the fully deprotonated bis-amidate ligands. In the case of the compound with the naphthalene derivative (9), the analytical and spectroscopic data suggest the occurrence of a low spin Co(II) complex. The weakening of the ligand field strength of the tetradentate bis-amidate ligand in the naphthalene derivative (5-6-5 ring-membered fused chelate) when compared to the situation in complexes 5-8 (5-5-5 ring-membered fused chelate) would account for this feature.

[Opinion of heads of schools about the impact of school setting factors on the attitude of children and youngsters regarding smoking]

AIM

Knowing the influence of school environment on children and teenagers' attitudes about tobacco consumption.

METHODS

A survey was carried on 3.050 Spanish school headmasters (16% of the total in Spain), who were asked about the main variables related to the school environment able to influence the attitude of children and teenagers towards tobacco, such as the fulfilment of the official anti-tobacco legislation at educational centres, the education for nicotine poisoning prevention, or the teachers attitudes about tobacco, among others. Multiple regressions were made so as to value the variables that most influence the pupils' tasting tobacco and becoming usual smokers.

RESULTS

In the opinion of the headmasters the variables that individually most influence the percentage of pupils that have tasted tobacco are the percentage of smoker teachers (beta 0.21) and the percentage of teachers who smoke in the presence of pupils (beta 0.091), as on the percentage of students usual smokers (beta 0.21 and 0.19 respectively). All the variables from school environment analysed jointly, explain some percentages of variance of the 9.65% and 10.7% of the estimated percentages of pupils who have tasted tobacco and pupils that are usual smokers, respectively.

CONCLUSIONS

The efforts most be doubled, in order to reach the real fulfilment of the official anti-tobacco legislation in all educational centres and the pupils receive teachings for the prevention of tabaquisme in the context of Health Education, since these measures may make the schools play a more determinant role in the prevention of the nicotinism.

[Epidemiological study of chronic obstructive pulmonary disease in Spain (IBERPOC): prevalence of chronic respiratory symptoms and airflow limitation]

The prevalence of chronic respiratory symptoms and chronic airflow limitation (CAFL) was determined in a multicentric epidemiological study carried out in seven different areas of Spain. Based on a target population of 236,412 persons, a random census sample of 4,035 individuals between 40 and 69 years of age was chosen. Subjects answered several questionnaires and performed spirometric tests followed by a bronchodilation test if bronchial obstruction was detected. Respiratory symptoms were reported by 48% of the population (95% CI: 46.4-49.5%) with greater frequency of symptoms among men than women (55.2% versus 41%, p < 0.001). The following levels of prevalence of chronic symptoms were found: cough, 13.5% (95% CI: 12.5-14.6%); expectoration, 10.7% (95% CI: 9.7-11.6%); dyspnea after one flight of stairs, 10.4% (95% CI: 9.5-11.4%); and wheezing, 40.2% (95% CI: 38.7-41.7%). The prevalence of chronic bronchitis (CB) was 4.8% (95% CI: 4.1-5.4%) and was more frequent among men than among women (8.3% and 1.4%, respectively; p < 0.001). Asthma had been diagnosed previously in 4.9% (95% CI: 4.2-5.5%), more often in women than in men (5.8% and 3.8%, respectively; p < 0.003). CAFL was found in 10.6% (95% CI: 9.6-11.5%), 15.8% in men and 5.5% in women (p < 0.001). All respiratory symptoms except asthma were more frequent among smokers than among ex-smokers, and in turn were more common among ex-smokers than non-smokers. The frequency of symptoms increased in accordance with accumulated smoking. The prevalence of CB and CAFL was vastly different from one region to another. Multivariate analysis showed that factors associated independently with the appearance of CB were smoking, age over 60 years, male sex and having worked in industry. In conclusion, respiratory symptoms, including CB and CAFL, are common in the Spanish population. Smoking and amount of smoking are directly related to the frequency of such symptoms. Substantial differences were found in the prevalence of CB and CAFL among the regions where the study was performed.

[Epidemiological study of chronic obstructive pulmonary disease in Spain (IBERPOC): recruitment and field work]

Chronic obstructive pulmonary disease (COPD) is a large-scale social and health problem. Because prevalence studies have been performed only in certain areas of Spain, the Spanish Society of Pneumology and Chest Surgery initiated the IBERPOC study with the aim of determining the prevalence of COPD in several parts of the country. IBERPOC is a multicenter, population-based epidemiological study in which subjects have been selected randomly. Seven full-time pneumologists work full-time in seven different areas of Spain. A study of this nature involves a series of difficulties that should be taken into account at the time of planning studies of a similar nature. After 5,827 attempts to reach subjects, a total of 4,967 useful contacts were made, to provide 97.3% of the 5,104 contacts expected. Of those 4,967 useful contacts, 4,035 subjects completed interviews. Among the 932 refusals, 882 (94.6%) agreed to answer a short telephone questionnaire. The field work took 13 months to complete, 30% more time than had been anticipated. The rates at which subjects could not be traced differed from one zone to another, ranging between 5% and 30%; higher rates were attributable to the absence of telephone data in the corresponding census report. In one zone, the dispersion of the census population over a very large area supposed greater difficulty and delay in carrying out the study. In conclusion, the rate of participation and the time required for recruitment can be considered satisfactory. The performance of field work by trained, full-time pneumologists has been essential to the development and quality of the study. Similar epidemiological studies should consider problems derived from the lack of adequate census data, as well as to avoid defining areas of extreme population dispersion in order to facilitate field work.