TiO2 bioactive implant surfaces doped with specific amount of Sr modulate mineralization.

One of the main problems that remain in the implant industry is poor osseointegration due to bioinertness of implants. In order to promote bioactivity, calcium (Ca), phosphorus (P) and strontium (Sr) were incorporated into a TiO2 porous layer produced by micro-arc oxidation. Ca and P as bioactive elements are already well reported in the literature, however, the knowledge of the effect of Sr is still limited. In the present work, the effect of various amounts of Sr was evaluated and the morphology, chemical composition and crystal structure of the oxide layer were investigated. Furthermore, in vitro studies were carried out using human osteoblast-like cells. The oxide layer formed showed a triplex structure, where higher incorporation of Sr increased Ca/P ratio, amount of rutile and promoted the formation of SrTiO3 compound. Biological tests revealed that lower concentrations of Sr did not compromise initial cell adhesion neither viability and interestingly improved mineralization. However, higher concentration of Sr (and consequent higher amount of rutile) showed to induce collagen secretion but with compromised mineralization, possibly due to a delayed mineralization process or induced precipitation of deficient hydroxyapatite. Ca-P-TiO2 porous layer with less concentration of Sr seems to be an ideal candidate for bone implants.

The UFM1 Pathway Impacts HCMV US2-Mediated Degradation of HLA Class I.

To prevent accumulation of misfolded proteins in the endoplasmic reticulum, chaperones perform quality control on newly translated proteins and redirect misfolded proteins to the cytosol for degradation by the ubiquitin-proteasome system. This pathway is called ER-associated protein degradation (ERAD). The human cytomegalovirus protein US2 induces accelerated ERAD of HLA class I molecules to prevent immune recognition of infected cells by CD8+ T cells. Using US2-mediated HLA-I degradation as a model for ERAD, we performed a genome-wide CRISPR/Cas9 library screen to identify novel cellular factors associated with ERAD. Besides the identification of known players such as TRC8, p97, and UBE2G2, the ubiquitin-fold modifier1 (UFM1) pathway was found to affect degradation of HLA-I. UFMylation is a post-translational modification resembling ubiquitination. Whereas we observe ubiquitination of HLA-I, no UFMylation was detected on HLA-I or several other proteins involved in degradation of HLA-I, suggesting that the UFM1 pathway impacts ERAD in a different manner than ubiquitin. Interference with the UFM1 pathway seems to specifically inhibit the ER-to-cytosol dislocation of HLA-I. In the absence of detectable UFMylation of HLA-I, UFM1 may contribute to US2-mediated HLA-I degradation by misdirecting protein sorting indirectly. Mass spectrometry analysis of US2-expressing cells showed that ribosomal proteins are a major class of proteins undergoing extensive UFMylation; the role of these changes in protein degradation may be indirect and remains to be established.

How an environmental issue could turn into useful high-valued products: The olive mill wastewater case.

Carbon-based nanomaterials have been directly synthesized from olive mill wastewaters (OMWWs) for the first time, using expedite and simple environmental-friendly procedures. The OMWWs collected from a mill operating by a two-phase centrifugation system, after being heated (150-300 °C) solely or in the presence of additives for 2-12 h, furnished nanostructured materials in high yields. Under an optimised set of reaction conditions here described, the resultant as-synthetized aqueous dispersions of carbon nanoparticles exhibit outstanding fluorescence emission properties, which encompass an astonishing quantum yield (ΦF > 0.4). The as-prepared carbon nanomaterials show excitation-dependent emissions covering the whole visible spectrum, with a predominant high glow in the blue-green region, and a remarkable photostability. The relevant features attained by the nanomaterials here reported, allied to their easy synthesis and carbon source affordability, render them with unique capabilities to be used in several current and emerging technological applications, namely in bioimaging and nanomedicine, sensorial analysis, (photo)catalysis and optoelectronics. The as-synthesized nanoparticles show a remarkable high sensitivity and selectivity towards haemoglobin.

The influence of TAP1 and TAP2 gene polymorphisms on TAP function and its inhibition by viral immune evasion proteins.

Herpesviruses encode numerous immune evasion molecules that interfere with the immune system, particularly with certain stages in the MHC class I antigen presentation pathway. In this pathway, the transporter associated with antigen processing (TAP) is a frequent target of viral immune evasion strategies. This ER-resident transporter is composed of the proteins TAP1 and TAP2, and plays a crucial role in the loading of viral peptides onto MHC class I molecules. Several variants of TAP1 and TAP2 occur in the human population, some of which are linked to autoimmune disorders and susceptibility to infections. Here, we assessed the influence of naturally occurring TAP variants on peptide transport and MHC class I expression. In addition, we tested the inhibitory capacity of three viral immune evasion proteins, the TAP inhibitors US6 from human cytomegalovirus, ICP47 from herpes simplex virus type 1 and BNLF2a from Epstein-Barr virus, for a series of TAP1 and TAP2 variants. Our results suggest that these TAP polymorphisms have no or limited effect on peptide transport or MHC class I expression. Furthermore, our study indicates that the herpesvirus-encoded TAP inhibitors target a broad spectrum of TAP variants; inhibition of TAP is not affected by the naturally occurring polymorphisms of TAP tested in this study. Our findings suggest that the long-term coevolution of herpesviruses and their host did not result in selection of inhibitor-resistant TAP variants in the human population.

Surface photochemistry: alloxazine within nanochannels of Na+ and H + ZSM-5 zeolites.

This work reports the surface photochemistry study of alloxazine adsorbed within nanochannels of MFI zeolites, namely in a series of Na+ and H+ ZSM-5 zeolites where the hydrophobic and hydrophilic character of the host varies systematically. Laser-induced room temperature and 77 K luminescence of air-equilibrated solid powdered samples of alloxazine adsorbed onto the two sets of zeolites, which we will name NaZSM-5 and HZSM-5, revealed the existence of a single emission of alloxazine as a broad band centred at about 450 nm in some cases, while in others an emission with a maximum at about 510 nm was detected. The decay times of the alloxazine emission vary greatly going from solution to entrapment within the nanochannels of the ZSM-5 zeolites. In the latter case a lifetime distribution analysis has shown that the longest lifetime for the alloxazine fluorescence emission exists in the case where an isoalloxazine-type emission was detected, i.e. whenever the hydrophobic character of the host increases. Alloxazine entrapped in the more acidic zeolites exists in the form of emissive monomers. However, alloxazine emits both from monomeric and aggregated emissive forms in the case of the hydrophobic zeolites. These data indicate the formation of planar dimers of alloxazine whenever the number of active sites in the zeolite decreases. These dimers have to be formed at the intersections of the zig-zag and linear nanochannels of the zeolite since there is no space available for their formation inside the zeolite channels. The isoalloxazine tautomers are formed due to the existence of alloxazine dimers which may undergo double proton transfer in the excited state, following laser excitation. Delayed fluorescence of alloxazine was also detected for the HZSM-5 and NaZSM-5 entrapment both at room temperature and at 77 K. The present study is paradigmatic as regards the host influence on the photochemistry of the guest.

[Aedes aegypti (l.) population in an endemic area of dengue in Southeast Brazil]. / População de Aedes aegypti (l.) em área endêmica de dengue, Sudeste do Brasil.

OBJECTIVE: A Aedes aegypti population from an area of dengue transmission was studied to determine mosquito's frequency, spatial distribution, parity, its ovarian development and midgut contents. METHODS: The study carried out in São José do Rio Preto country, São Paulo, SP, Brazil. Low and intermediate socioeconomic level regions were chosen to the study, which was carried out 1996 and 1997. Using a manual electric aspirator, captures were performed inside and outside the houses. Dissections were conducted to allow classify female mosquitoes according to their physiologic state. RESULTS: One hundred and eighty-eight males and 189 females were captured in both regions. A general index of 0.46 Ae. aegypti females per house was determined. Of the total sample, 82.4% of males and 87.3% of females were collected indoors. Greater proportions of females were found in the region of low socioeconomic level, and higher population density. One hundred and forty-eight female mosquitoes were analyzed: 27.0% were nulliparous and 10.1% parous. The rest were classified as Christophers and Mer's (C & M) phases III to V, 28.0% of which had red blood in their midgut. Of the total female population, 87.9% had bloodmeals. CONCLUSIONS: The mosquito species revealed a high degree of endophily. There was a higher proportion of nulliparous mosquitoes, although the majority of the females were classified as C & M's phases III to V. These results highlight both the great number of females who had had bloodmeals, and the lack of gonotrophic concordance.

[An evaluation of municipal actions in the control of dengue vectors in the region of São José do Rio Prêto, São Paulo, 1989 to 1995]. / Avaliação de ações municipais de combate a vetores da dengue na região de São José do Rio Prêto, São Paulo, 1989 a 1995.

The aim of this study was to determine the coverage of municipal activities in terms of the control of Aedes aegypti and/or Aedes albopictus by routine house-to-house visits and by emergency activity, carried out between 1989 and 1995 in the area of São José do Rio Prêto, São Paulo State, and to evaluate the cross-correlation between them and the Breteau index (BI). For towns with up to 50,000 real estate properties, the joint coverage by routine and emergency activities was mostly appropriate and the routine activities showed a negative cross-correlation with the BI. For the county seat (more than 50,000 real estate properties), the coverage provided by the above activities was not correlated with the BI. In general, the coverage was inversely proportional to town size. Emergency activities did not show a correlation with the BI in any town size range, proving to be ineffective.

[Geographical distribution of dengue and socioeconomic factors in an urban locality in southeastern Brazil]. / Distribuição espacial da dengue e determinantes socioeconômicos em localidade urbana no Sudeste do Brasil.

INTRODUCTION: The incidence of dengue (serum type I) in the city of S. José do Rio Preto during an epidemic which occurred in the first semester of 1995 is analyzed in terms of geographical areas defined by socioeconomic variables. MATERIAL AND METHOD: The epidemiological method of analysis is the "ecological study" type. To calculate the coefficient of incidence of dengue, all cases both confirmed and reported between January and July, 1995 are considered. The environmental units are defined according to socioeconomic variables based on the IBGE (Brazilian Institute of Geography and Statistics) Census of 1991, through cluster analysis. The linear correlation coefficient between coefficient of incidence and environmental variables is also calculated. RESULTS AND DISCUSSION: Three distinct environmental units are identified and described on the basis of both economic and educational level. The coefficient of incidence of dengue varied in accordance with the environmental unit: in the unit of low standard the coefficient was 2.7 times greater than that of the unit of highest standard, showing that in these units the determining factors of dengue have a differentiating effect. The roles of some of the determining factors such as population density, basic sanitary services and vector density are discussed. The importance of this study for the control of dengue is also emphasized.

Fibrilação e flutter atriais / Atrial fibrillation and flutter

No presente artigo os autores fazem uma breve revisão da clínica dos mecanismos eletrofisiológicos do Flutter e Fibrilação atriais. Procuram de forma sucinta fazer uma atualização terapêutica, uma vez que o grande avanço ocorrido na última década na área de eletrofisiologia clínica possibilitou não apenas um melhor conhecimento dos mecanismos das arritmias cardíacas e o mecanismo de ação das drogas antiarrítmicas, como também o tratamento não farmacológico das mesmas. Nesta revisão, os autores procuram abranger o tratamento farmacológico das arritmias, a indicação atual para a anticoagulação na prevenção dos fenômenos tromboembólicos e avaliar as indicaçöes atuais, sucessos e limitaçöes da terapia não farmacológica dos distúrbios do ritmo em questão.

[Description of the colonization of Aedes albopictus (Diptera: culicidae) in the region of Saõ José do Rio Preto, SP, 1991-1994]. / Descrição da colonização de Aedes albopictus (Diptera: culicidae) na região de São José do Rio Preto, SP, 1991-1994.

This study aims to describe and analyze the colonization of Aedes albopictus whose presence was detected in 1991 in the area of Sào José do Rio. Preto already colonized by the Aedes aegypti. Year and month of occurrence, counties, composition and location of larval samples, kinds of containers, average number of larvae an Breteau Index bare been analyzed from the information obtained in measurements of larval density by Superintendência de Controle de Endemias (SUCEN). The presence of Aedes albopictus was ascertained in 34 towns up to December 1994. The colonization of the area by the mosquito is still reduced showing some differences in relation to Aedes aegypti such as greater ratio outdoors, occupying container in different proportions. The average number of Aedes albopictus larvae has had influence of larvae of another species. It has showed a seasonal behavior similar to Aedes aegypti and it has moved from east to west direction.

[Alberprosenia malheiroi Serra, Atzingen & Serra, 1987 (Hemiptera, Reduviidae). Redescription and bionomics]. / Alberprosenia malheiroi Serra, Atzingen & Serra, 1987 (Hemiptera, Reduviidae). Redescrição e bionomia.

Alberprosenia malheiroi n. sp. first became known through an informal publication of a paper submitted a Congress, in 1980. The same diagnosis with a photograph was published in 1987, but no formal description has yet been made. The present authors describe adults and immature instars, establish a sintypical series and introduce bionomic data and data on the rearing of this species in insectary. The most evident differences between A. malheiroi n. sp. and A. goyovargasi, the former generic species, are the general colour pattern which is completely black; the interocular area, wider than an eye in dorsal view; the acute apex in collar tubercules and the significantly larger size, almost double that of the latter specie. The eggs are small attach themselves to the substratum in groups of either 3 or 4, are elipsoid with no lateral flattening, having a convex and prominent operculum, without conspicuous structures. Nymphs have the typical tribal and generic characteristics in each stage, the anteocular region being shorter than the postocular one. Pilosity appears in the second instar and becomes more evident with instar development. A. malheiroi n. sp. was captured in a forest, in wild (palm-tree) ecotopes associated with bats or birds, in the State of Para, Brazil. Trypanosoma cruzi was not found in any specimens. These triatomines were reared in +/- 25 degrees C and +/- 60% RH, the insects are quick and fly without difficulty. They fed well on pigeons and bats but not on rats, mice or hamsters. The eggs incubation period was thirteen days on average, and the evolution time of the nymphal period was a hundred and thirty two days on average.