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In the rapidly expanding field of peptide therapeutics, the short in vivo half-life of peptides represents a considerable limitation for drug action. D-peptides, consisting entirely of the dextrorotatory enantiomers of naturally occurring levorotatory amino acids (AAs), do not suffer from these shortcomings as they are intrinsically resistant to proteolytic degradation, resulting in a favourable pharmacokinetic profile. To experimentally identify D-peptide binders to interesting therapeutic targets, so-called mirror-image phage display is typically performed, whereby the target is synthesized in D-form and L-peptide binders are screened as in conventional phage display. This technique is extremely powerful, but it requires the synthesis of the target in D-form, which is challenging for large proteins. Here we present finDr, a novel web server for the computational identification and optimization of D-peptide ligands to any protein structure ( https://findr.biologie.uni-freiburg.de/ ). finDr performs molecular docking to virtually screen a library of helical 12-mer peptides extracted from the RCSB Protein Data Bank (PDB) for their ability to bind to the target. In a separate, heuristic approach to search the chemical space of 12-mer peptides, finDr executes a customizable evolutionary algorithm (EA) for the de novo identification or optimization of D-peptide ligands. As a proof of principle, we demonstrate the validity of our approach to predict optimal binders to the pharmacologically relevant target phenol soluble modulin alpha 3 (PSMα3), a toxin of methicillin-resistant Staphylococcus aureus (MRSA). We validate the predictions using in vitro binding assays, supporting the success of this approach. Compared to conventional methods, finDr provides a low cost and easy-to-use alternative for the identification of D-peptide ligands against protein targets of choice without size limitation. We believe finDr will facilitate D-peptide discovery with implications in biotechnology and biomedicine.

Patients with acute myeloid leukemia (AML) often achieve remission after allogeneic hematopoietic cell transplantation (allo-HCT) but subsequently die of relapse driven by leukemia cells resistant to elimination by allogeneic T cells based on decreased major histocompatibility complex II (MHC-II) expression and apoptosis resistance. Here we demonstrate that mouse-double-minute-2 (MDM2) inhibition can counteract immune evasion of AML. MDM2 inhibition induced MHC class I and II expression in murine and human AML cells. Using xenografts of human AML and syngeneic mouse models of leukemia, we show that MDM2 inhibition enhanced cytotoxicity against leukemia cells and improved survival. MDM2 inhibition also led to increases in tumor necrosis factor-related apoptosis-inducing ligand receptor-1 and -2 (TRAIL-R1/2) on leukemia cells and higher frequencies of CD8+CD27lowPD-1lowTIM-3low T cells, with features of cytotoxicity (perforin+CD107a+TRAIL+) and longevity (bcl-2+IL-7R+). CD8+ T cells isolated from leukemia-bearing MDM2 inhibitor-treated allo-HCT recipients exhibited higher glycolytic activity and enrichment for nucleotides and their precursors compared with vehicle control subjects. T cells isolated from MDM2 inhibitor-treated AML-bearing mice eradicated leukemia in secondary AML-bearing recipients. Mechanistically, the MDM2 inhibitor-mediated effects were p53-dependent because p53 knockdown abolished TRAIL-R1/2 and MHC-II upregulation, whereas p53 binding to TRAILR1/2 promotors increased upon MDM2 inhibition. The observations in the mouse models were complemented by data from human individuals. Patient-derived AML cells exhibited increased TRAIL-R1/2 and MHC-II expression on MDM2 inhibition. In summary, we identified a targetable vulnerability of AML cells to allogeneic T-cell-mediated cytotoxicity through the restoration of p53-dependent TRAIL-R1/2 and MHC-II production via MDM2

O Staphylococcus aureus faz parte da microbiota da pele, mucosas e nasofaringe de várias espécies animais, incluindo o homem, mas também está associado a enfermidades como abscessos, bacteremias, endocardites e osteomielites, além de se mostrar resistente a múltiplas drogas. Este trabalho foi realizado com a finalidade de avaliar o efeito do gás ozônio, dissolvido em água, sobre o S. aureus. Foram preparadas suspensões de S. aureus, com concentrações variando de 10(6) a 10(16) microrganismos/ml. De cada suspensão recém-preparada foi retirado 1 ml e adicionado a 99 ml de água destilada estéril (com ou sem prévia ozonização), em um reator de cristal. Foram preparadas diluições seriadas (1/10) das suspensões testadas e inoculado 0,1 ml de cada suspensão em Tryptic Soy Agar, incubadas a 37ºC por 24 h, quando então se procedeu à contagem das UFC. Os resultados obtidos mostraram que o tempo máximo para a inativação total das bactérias tratadas com água previamente ozonizada (0,6 mg/ml) foi de 5’25" e, para a água não previamente ozonizada, foi de 23’45", indicando um efeito antibacteriano mais rápido da água previamente ozonizada, frente ao S. aureus.Staphylococcus aureus belongs to the normal flora of the skin, mucosa and nasopharynx of several animal species, including man, but it is also associated to illnesses such as abscesses, bacteremia, endocarditis and osteomyelitis, besides showing resistance to multiple drugs. The purpose of this paper was to evaluate the disinfecting ability of ozone when dissolved in water. Suspensions of Staphylococcus aureus with concentrations varying from 10(6) to 10(16) microorganisms/ml were prepared. One milliliter of each recently prepared suspension was added to 99 ml of distilled water (with or without previous ozonization) contained in a crystal reactor. Aliquots of 0.1 ml of this new suspension were taken at various time intervals and, then, serially diluted and inoculated on plaques. The data indicated that there was difference in the disinfecting effect when distilled water was used with and without previous ozonization.

Abundance estimates are presented for the humpback whales wintering off Brazil which ‘visit’ a surveyed area off Abrolhos Bank and display fluke-exposing behaviour. The study is based on photo-identification data collected between 1996 and 2000. Chapman-corrected Petersen estimates for all pairs of data result in estimates from 1,948 individuals up to 3,001 with coefficients of variation around 0.25. A more elaborate closed population multiple-recapture maximum-likelihood estimate is 2,393 with 95% profile-likelihood confidence interval (CI=1,924, 3,060). Replacing the closed-population assumption with a population allowed to grow (or decrease) according to some constant rate over the study period, the maximum-likelihood estimate of population size for the year 2000 becomes 3,871 (CI=2,795, 5,542) associated to an estimated annual growth rate of 31% over the study period and in the surveyed area. Although the inclusion of the growth rate results in a less restrictive assumption about population size, it is unclear at this time how to interpret it since the population around the Abrolhos Bank is some (unknown) fraction of whales wintering off Brazil. Alternatively, a fit of Whitehead’s model allowing for emigration and re-immigration gives an estimate of about 3,000 whales (CI=2,500, 3,650).

No Oceano Atl?ntico Sul Ocidental as baleias jubarte migram a cada inverno para o banco dos Abrolhos (16?40 to 19?30 S; 37?25 to 38?57 W) para acasalamento e cria de filhotes. Entretanto, esta popula??o permanece geneticamente n?o caracterizada e suas ?reas de alimenta??o s?o ainda desconhecidas, uma vez que n?o h? pareamento fotogr?fico de indiv?duos entre Abrolhos e os s?tios de alimenta??o na Ant?rtida. A fim de examinar estas quest?es, sequenciamos um segmento de 450 pares de bases do DNA mitocondrial da regi?o controladora de baleias jubarte de Abrolhos (n=176) e das proximidades da Pen?nsula Ant?rtica (n=77). Um total de de 61, 17 e 13 hapl?tipos foram determinados respectivamente no Brasil e nas ?reas I e II da Ant?rtida. A variabilidade gen?tica da ?rea de reprodu??o brasileira foi alta, similar ? de outros s?tios reprodutivos do Hemisf?rio Sul. A propor??o de hapl?tipos compartilhados e a dist?ncia gen?tica demonstraram uma maior semelhan?a entre as duas regi?es ant?rticas que entre o Brasil e qualquer uma destas ?reas. Estes resultados indicam que as popula??es de baleias jubarte das ?reas I e II da Ant?rtida parecem n?o possuir uma clara diferencia??o e que os limites entre as ?reas I e II correntemente definidos pela Comiss?o Internacional da Baleia devem ser deslocados para leste. Sugerimos que a ?rea de alimenta??o da popula??o de baleias jubarte brasileiras n?o estaria na Pen?nsula Ant?rtica ou pr?ximo a ela, mas pode estar localizada na por??o leste da ?rea II, no mar de Weddell ou pr?ximo ?s ilhas Ge?rgias do Sul.

Staphylococcus aureus belongs to the normal flora of the skin, mucosa and nasopharynx of several animal species, including man, but it is also associated to illnesses such as abscesses, bacteremia, endocarditis and osteomyelitis, besides showing resistance to multiple drugs. The purpose of this paper was to evaluate the disinfecting ability of ozone when dissolved in water. Suspensions of Staphylococcus aureus with concentrations varying from 10(6) to 10(16) microorganisms/ml were prepared. One milliliter of each recently prepared suspension was added to 99 ml of distilled water (with or without previous ozonization) contained in a crystal reactor. Aliquots of 0.1 ml of this new suspension were taken at various time intervals and, then, serially diluted and inoculated on plaques. The data indicated that there was difference in the disinfecting effect when distilled water was used with and without previous ozonization. O Staphylococcus aureus faz parte da microbiota da pele, mucosas e nasofaringe de várias espécies animais, incluindo o homem, mas também está associado a enfermidades como abscessos, bacteremias, endocardites e osteomielites, além de se mostrar resistente a múltiplas drogas. Este trabalho foi realizado com a finalidade de avaliar o efeito do gás ozônio, dissolvido em água, sobre o S. aureus. Foram preparadas suspensões de S. aureus, com concentrações variando de 10(6) a 10(16) microrganismos/ml. De cada suspensão recém-preparada foi retirado 1 ml e adicionado a 99 ml de água destilada estéril (com ou sem prévia ozonização), em um reator de cristal. Foram preparadas diluições seriadas (1/10) das suspensões testadas e inoculado 0,1 ml de cada suspensão em Tryptic Soy Agar, incubadas a 37ºC por 24 h, quando então se procedeu à contagem das UFC. Os resultados obtidos mostraram que o tempo máximo para a inativação total das bactérias tratadas com água previamente ozonizada (0,6 mg/ml) foi de 5’25" e, para a água não previamente ozonizada, foi de 23’45", indicando um efeito antibacteriano mais rápido da água previamente ozonizada, frente ao S. aureus.

The Abrolhos Bank (off the State of Bahia, northeastern Brazil) is the most important breeding and calving ground for humpback whales, Megaptera novaeangliae, in the western South Atlantic. The area is shallow with a mean depth of 30m and a group of five islands (the Abrolhos Archipelago) is located in the northern portion of the Bank. Data collected from 1992 to 1998 were analysed to identify possible different habitat use patterns by different humpback whale group types. An analysis of variance found differences in the mean water depths where different group types were recorded: single whales, 18.9m (se = 0.505); pairs, 18.6m (se = 0.386); competitive groups, 19.1m (se = 0.573); mother-calf pairs, 15.8m (se = 0.373); mother-calf-principal escort, 14.9m (se = 0.489); and competitive group with mother-calf pair, 16.4m (se = 0.889). With the exception of competitive groups, those containing calves (mother-calf alone or mother-calf-principal escort) occurred in significantly shallower water than non-calf groups (Tukey test, p