Synthesis and biological evaluation of ternary silver compounds bearing N,N-chelating ligands and thiourea: X-ray structure of [{Ag(bpy) (mu-tu)}(2)](NO3)(2) (bpy=2,2 '-bipyridine; tu = thiourea)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

New ligands of the cellular retinoic acid-binding protein 2 (CRABP2) suggest a role for this protein in chromatin remodeling

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Finite-difference calculation of donor energy levels in a spherical quantum dot subject to a magnetic field

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Vanadium complexes with hydrazone or thiosemicarbazone ligands as potential anti-mycobacterium tuberculosis agents

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influence of lineage of oocyte donor on the yield and morphology of oocytes recovered by ultrasound-guided follicular aspiration in nellore cows

The objective of this study was to investigate the influence of lineage of oocytes donors on the number and quality of oocytes obtained through ultrasound-guided follicular aspiration in Nellore breed cows derived from two lineages of bulls (Karvadi; K and Taj-Mahal; T). Both maternal (Km and Tm) and paternal (Kp and Tp) lineages, as well as their combinations were investigated. Oocyte aspirations were repeatedly performed with an aspiration interval of 15 days in 56 donor females. Recovered cumulus oocyte-complexes (COCs) were counted, morphologically examined and classified into seven categories (grades from I to VII) according to the number of layers of the cumulus oocyte and cytoplasm appearance. The mean number of oocytes retrieved from donors of lineage Tp-Tm was significantly higher (28.23±1.92, P<0.05) than those obtained from lineages Kp-Tm, Kp-Km, and Tp-Km (21.34±1.32, 21.28±1.73, and 16.72±1.31, respectively). There was no significant difference in the mean number of recovered oocytes between donors of lineages Kp-Km and Kp-Tm, whereas animals of lineage Tp-Km yielded the lowest number of oocytes. Higher mean number of grade III oocytes was recovered from donors of lineage Kp than lineage Tp (10.11±0.66 versus 8.79±0.58, respectively), with more grade III oocytes being obtained in both lineages as compared to the others. Paternal lineage did not influence the quality of recovered oocytes in any other category, but both Kp and Tp yielded a great mean number of oocytes graded as I, II, and III (3.14±0.21; 4.93±0.33, and 10.11±0.66 versus 3.19±0.21, 5.59±0.44, and 8.79±0.58, respectively) than those classified as IV, V, VI, and VII. However, when considering the data from the maternal lineage significantly more oocytes (P<0.05) of grade I, II and III were obtained from Taj-Mahal (11.67 ± 0.67, 5.9±0.42 and 3.64±0.25, respectively) than for lineage Karvadi, with similar results for oocytes of grades IV, V, VI, and VII. Similarly to the paternal lineage, the number of oocytes of grade III was superior (P<0.05) when compared to other categories for both lineages. In conclusion, we demonstrate here a direct influence of lineage of oocyte donor on the production and quality of oocytes obtained through ultrasound-guided follicular aspiration in Nellore cows.

Compostos de Pd(II) contendo ligantes N,S-doadores: síntese, caracterização e estudo da atividade citotóxica

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Aberrant transcript produced by a splice donor site deletion in the TECTA gene is associated with autosomal dominant deafness in a Brazilian family

We ascertained a Brazilian family with nine individuals affected by autosomal dominant nonsyndromic sensorineural hearing loss. The bilateral hearing loss affected mainly mid-high frequencies, was apparently stable with an early onset. Microsatellites close to the DFNA8/DFNA12 locus, which harbors the TECTA gene, showed significant multipoint lod scores (32) close to marker D11S4107. Sequencing of the exons and exon-intron boundaries of the TECTA gene in one affected subject revealed the deletion c.5383 + 5delGTGA in the 5' end of intron 16, that includes the last two bases of the donor splice site consensus sequence. This mutation segregates with deafness within the family. To date, 33 different TECTA mutations associated with autossomal dominant hearing loss have been described. Among them is the mutation reported herein, first described by Hildebrand et al. (2011) in a UK family. The audioprofiles from the UK and Brazilian families were similar. In order to investigate the transcripts produced by the mutated allele, we performed cDNA analysis of a lymphoblastoid cell line from an affected heterozygote with the c.5383 + 5delGTGA and a noncarrier from the same family. The analysis allowed us to identify an aberrant transcript with skipping of exon 16, without affecting the reading frame. One of the dominant TECTA mutations already described, a synonymous substitution in exon 16 (c.5331 G<A), was also shown to affect splicing resulting in an aberrant transcript lacking exon 16. Despite the difference in the DNA level, both the synonymous substitution in exon 16 (c.5331 G<A) and the mutation described herein affect splicing of exon 16, leading to its skipping. At the protein level they would have the same effect, an in-frame deletion of 37 amino-acids (p.S1758Y/G1759_N1795del) probably leading to an impaired function of the ZP domain. Thus, like the TECTA missense mutations associated with dominant hearing loss, the c5383 + 5delGTGA mutation does not have an inactivating effect on the protein. (C) 2012 Elsevier B.V. All rights reserved.

Treatment of Nuclear-Donor Cells or Cloned Zygotes with Chromatin-Modifying Agents Increases Histone Acetylation But Does Not Improve Full-Term Development of Cloned Cattle

Although somatic cell nuclear transfer (SCNT) is a promising tool, its potential use is hampered by the high mortality rates during the development to term of cloned offspring. Abnormal epigenetic reprogramming of donor nuclei after SCNT is thought to be the main cause of this low efficiency. We hypothesized that chromatin-modifying agents (CMAs) targeting chromatin acetylation and DNA methylation could alter the chromatin configuration and turn them more amenable to reprogramming. Thus, bovine fibroblasts were treated with 5-aza-2'-deoxycytidine (AZA) plus trichostatin (TSA) or hydralazine (HH) plus valproic acid (VPA) whereas, in another trial, cloned bovine zygotes were treated with TSA. The treatment of fibroblasts with either AZA + TSA or HH + VPA increased histone acetylation, but did not affect the level of DNA methylation. However, treatment with HH + VPA decreased cellular viability and proliferation. The use of these cells as nuclear donors showed no positive effect on pre- and postimplantation development. Regarding the treatment of cloned zygotes with TSA, treated one-cell embryos showed an increase in the acetylation patterns, but not in the level of DNA methylation. Moreover, this treatment revealed no positive effect on pre- and postimplantation development. This work provides evidence the treatment of either nuclear donor cells or cloned zygotes with CMAs has no positive effect on pre- and postimplantation development of cloned cattle.

Human immunodeficiency virus prevalence, incidence, and residual risk of transmission by transfusions at Retrovirus Epidemiology Donor Study-II blood centers in Brazil

BACKGROUND: In Brazil nationally representative donor data are limited on human immunodeficiency virus (HIV) prevalence, incidence, and residual transfusion risk. The objective of this study was to analyze HIV data obtained over 24 months by the Retrovirus Epidemiology Donor Study-II program in Brazil. STUDY DESIGN AND METHODS: Donations reactive to third-and fourth-generation immunoassays (IAs) were further confirmed by a less-sensitive (LS) IA algorithm and Western blot (WB). Incidence was calculated for first-time (FT) donors using the LS-EIA results and for repeat donors with a model developed to include all donors with a previous negative donation. Residual risk was projected by multiplying composite FT and repeat donor incidence rates by HIV marker-negative infectious window periods. RESULTS: HIV prevalence among FT donors was 92.2/ 105 donations. FT and repeat donor and composite incidences were 38.5 (95% confidence interval [CI], 25.651.4), 22.5 (95% CI, 17.6-28.0), and 27.5 (95% CI, 22.0-33.0) per 100,000 person-years, respectively. Male and community donors had higher prevalence and incidence rates than female and replacement donors. The estimated residual risk of HIV transfusion transmission was 11.3 per 106 donations (95% CI, 8.4-14.2), which could be reduced to 4.2 per 106 donations (95% CI, 3.2-5.2) by use of individual-donation nucleic acid testing (NAT). CONCLUSION: The incidence and residual transfusion risk of HIV infection are relatively high in Brazil. Implementation of NAT will not be sufficient to decrease transmission rates to levels seen in the United States or Europe; therefore, other measures focused on decreasing donations by at-risk individuals are also necessary.

Transmission of clear cell tumor in a graft liver from cadaveric donor: Case report

Neoplasms in children after organ transplantation are related to the type and intensity of immunosuppression and the donorrecipient serostatus, especially in relation to the EpsteinBarr virus. The patient was a two-yr-old female child with biliary atresia who underwent a liver transplantation from a female cadaver donor. Two adults received kidney transplants from the same donor. Nine months after transplantation, one of the adult recipients developed an urothelial tumor in the kidney graft. Imaging tests were repeated monthly in the liver-transplanted child and revealed no abnormalities. However, one yr and two months after the transplantation, the patient developed episodes of fever. At that time, imaging and liver biopsy showed a clear cell tumor of urothelial origin in the graft and the disease was limited to the liver. The patient underwent liver retransplantation, and she is currently free of tumor recurrence. Although rare, the occurrence of tumors in the post-transplant period from cadaver donors, without previously diagnosed tumors, is one of the many problems encountered in the complex world of organ transplantation.

Capillary bioreactors based on human purine nucleoside phosphorylase: A new approach for ligands identification and characterization

The enzyme purine nucleoside phosphorylase (PNP) is a target for the discovery of new lead compounds employed on the treatment severe T-cell mediated disorders. Within this context, the development of new, direct, and reliable methods for ligands screening is an important task. This paper describes the preparation of fused silica capillaries human PNP (HsPNP) immobilized enzyme reactor (IMER). The activity of the obtained IMER is monitored on line in a multidimensional liquid chromatography system, by the quantification of the product formed throughout the enzymatic reaction. The Km value for the immobilized enzyme was about twofold higher than that measured for the enzyme in solution (255 +/- 29.2 mu M and 133 +/- 114.9 mu M, respectively). A new fourth-generation immucillin derivative (DI4G: IC50 = 40.6 +/- 0.36 nM), previously identified and characterized in HsPNP free enzyme assays, was used to validate the IMER as a screening method for HsPNP ligands. The validated method was also used for mechanistic studies with this inhibitor. This new approach is a valuable tool to PNP ligand screening, since it directly measures the hypoxanthine released by inosine phosphorolysis, thus furnishing more reliable results than those one used in a coupled enzymatic spectrophotometric assay. (C) 2011 Elsevier B.V. All rights reserved.

Number of recent sexual partners among blood donors in Brazil: associations with donor demographics, donation characteristics, and infectious disease markers

BACKGROUND: Brazilian blood centers ask candidate blood donors about the number of sexual partners in the past 12 months. Candidates who report a number over the limit are deferred. We studied the implications of this practice on blood safety. STUDY DESIGN AND METHODS: We analyzed demographic characteristics, number of heterosexual partners, and disease marker rates among 689,868 donations from three Brazilian centers between July 2007 and December 2009. Donors were grouped based on maximum number of partners allowed in the past 12 months for each center. Chi-square and logistic regression analysis were conducted to examine associations between demographic characteristics, number of sex partners, and individual and overall positive markers rates for human immunodeficiency virus (HIV), human T-lymphotropic virus Types 1 and 2, hepatitis B virus, hepatitis C virus, and syphilis. RESULTS: First-time, younger, and more educated donors were associated with a higher number of recent sexual partners, as was male sex in Sao Paulo and Recife (p < 0.001). Serologic markers for HIV and syphilis and overall were associated with multiple partners in Sao Paulo and Recife (p < 0.001), but not in Belo Horizonte (p = 0.05, p = 0.94, and p = 0.75, respectively). In logistic regression analysis, number of recent sexual partners was associated with positive serologic markers (adjusted odds ratio [AOR], 1.2-1.5), especially HIV (AOR, 1.9-4.4). CONCLUSIONS: Number of recent heterosexual partners was associated with HIV positivity and overall rates of serologic markers of sexually transmitted infections. The association was not consistent across centers, making it difficult to define the best cutoff value. These findings suggest the use of recent heterosexual contacts as a potentially important deferral criterion to improve blood safety in Brazil.

GM-CSF Priming Drives Bone Marrow-Derived Macrophages to a Pro-Inflammatory Pattern and Downmodulates PGE(2) in Response to TLR2 Ligands

In response to pathogen recognition by Toll-like receptors (TLRs) on their cell surface, macrophages release lipid mediators and cytokines that are widely distributed throughout the body and play essential roles in host responses. Granulocyte macrophage colony-stimulating factor (GM-CSF) is important for the immune response during infections to improve the clearance of microorganisms. In this study, we examined the release of mediators in response to TLR2 ligands by bone marrow-derived macrophages (BMDMs) primed with GM-CSF. We demonstrated that when stimulated with TLR2 ligands, non-primed BMDMs preferentially produced PGE(2) in greater amounts than LTB4. However, GM-CSF priming shifted the release of lipid mediators by BMDMs, resulting in a significant decrease of PGE(2) production in response to the same stimuli. The decrease of PGE(2) production from primed BMDMs was accompanied by a decrease in PGE-synthase mRNA expression and an increase in TNF-alpha and nitric oxide (NO) production. Moreover, some GM-CSF effects were potentiated by the addition of IFN-gamma. Using a variety of TLR2 ligands, we established that PGE(2) release by GM-CSF-primed BMDMs was dependent on TLR2 co-receptors (TLR1, TLR6), CD14, MyD88 and the nuclear translocation of NF kappa B but was not dependent on peroxisome proliferator-activated receptor-gamma (PPAR-gamma) activation. Indeed, GM-CSF priming enhanced TLR2, TLR4 and MyD88 mRNA expression and phospho-I kappa B alpha formation. These findings demonstrate that GM-CSF drives BMDMs to present a profile relevant to the host during infections.

Advanced QSAR Studies on PPAR delta Ligands Related to Metabolic Diseases

PPAR delta is a nuclear receptor that, when activated, regulates the metabolism of carbohydrates and lipids and is related to metabolic syndrome and type 2 diabetes. To understand the main interactions between ligands and PPAR delta, we have constructed 2D and 3D QSAR models and compared them with HOMO, LUMO and electrostatic potential maps of the compounds studied, as well as docking results. All QSAR models showed good statistical parameters and prediction outcomes. The QSAR models were used to predict the biological activity of an external test set, and the predicted values are in good agreement with the experimental results. Furthermore, we employed all maps to evaluate the possible interactions between the ligands and PPAR delta. These predictive QSAR models, along with the HOMO, LUMO and MEP maps, can provide insights into the structural and chemical properties that are needed in the design of new PPAR delta ligands that have improved biological activity and can be employed to treat metabolic diseases.

The impact of pretransplant donor-specific antibodies on graft outcome in renal transplantation: a six-year follow-up study

OBJECTIVE: The significance of pretransplant, donor-specific antibodies on long-term patient outcomes is a subject of debate. This study evaluated the impact and the presence or absence of donor-specific antibodies after kidney transplantation on short-and long-term graft outcomes. METHODS: We analyzed the frequency and dynamics of pretransplant donor-specific antibodies following renal transplantation from a randomized trial that was conducted from 2002 to 2004 and correlated these findings with patient outcomes through 2009. Transplants were performed against a complement-dependent T-and B-negative crossmatch. Pre- and posttransplant sera were available from 94 of the 118 patients (80%). Antibodies were detected using a solid-phase (Luminex (R)), single-bead assay, and all tests were performed simultaneously. RESULTS: Sixteen patients exhibited pretransplant donor-specific antibodies, but only 3 of these patients (19%) developed antibody-mediated rejection and 2 of them experienced early graft losses. Excluding these 2 losses, 6 of 14 patients exhibited donor-specific antibodies at the final follow-up exam, whereas 8 of these patients (57%) exhibited complete clearance of the donor-specific antibodies. Five other patients developed "de novo'' posttransplant donor-specific antibodies. Death-censored graft survival was similar in patients with pretransplant donor-specific and non-donor-specific antibodies after a mean follow-up period of 70 months. CONCLUSION: Pretransplant donor-specific antibodies with a negative complement-dependent cytotoxicity crossmatch are associated with a risk for the development of antibody-mediated rejection, although survival rates are similar when patients transpose the first months after receiving the graft. Our data also suggest that early posttransplant donor-specific antibody monitoring should increase knowledge of antibody dynamics and their impact on long-term graft outcome.