Sucrose Fermentation by Brazilian Ethanol Production Yeasts in Media Containing Structurally Complex Nitrogen Sources

Four Saccharomyces cerevisiae Brazilian industrial ethanol production strains were grown, under shaken and static conditions, in media containing 22% (w/v) sucrose supplemented with nitrogen sources varying from a single ammonium salt (ammonium sulfate) to free amino acids (casamino acids) and peptides (peptone). Sucrose fermentations by Brazilian industrial ethanol production yeasts strains were strongly affected by both the structural complexity of the nitrogen source and the availability of oxygen. Data suggest that yeast strains vary in their response to the nitrogen source`s complex structure and to oxygen availability. In addition, the amount of trehalose produced could be correlated with the fermentation performance of the different yeasts, suggesting that efficient fuel ethanol production depends on finding conditions which are appropriate for a particular strain, considering demand and dependence on available nitrogen sources in the fermentation medium.

Glucose and Fructose Fermentation by Wine Yeasts in Media Containing Structurally Complex Nitrogen Sources

Glucose and fructose fermentations by industrial yeasts strains are strongly affected by both the structural complexity of the nitrogen Source and the availability of oxygen. In this Study two Saccharomyces cerevisiae industrial wine strains were grown, under shaken and static conditions, in a media containing either a) 20% (w/v) glucose, or b) 10% (w/v) fructose and 10% (w/v) glucose or c) 20% (w/v) fructose, all supplemented with nitrogen Sources varying from a single ammonium salt (ammonium Sulfate) to free amino acids (casamino acids) and peptides (peptone). Data Suggest that 1 complex Structured nitrogen source is not submitted to the same control mechanisms as those involved in the utilization of simpler structured nitrogen Sources, and mutual interaction between carbon and nitrogen Sources, including the mechanisms involved ill the regulation of aerobic/anaerobic metabolism, may play in important role in defining yeast fermentation performance and the differing response to the structural complexity of the nitrogen Source, with a strong impact oil fermentation performance.

Highlights from the III International Symposium of Thrombosis and Anticoagulation (ISTA), October 14-16, 2010, Sao Paulo, Brazil

To discuss and share knowledge around advances in the care of patients with thrombotic disorders, the Third International Symposium of Thrombosis and Anticoagulation was held in So Paulo, Brazil, from October 14-16, 2010. This scientific program was developed by clinicians for clinicians, and was promoted by four major clinical research institutes: the Brazilian Clinical Research Institute, the Duke Clinical Research Institute of the Duke University School of Medicine, the Canadian VIGOUR Centre, and the Uppsala Clinical Research Center. Comprising 3 days of academic presentations and open discussion, the symposium had as its primary goal to educate, motivate, and inspire internists, cardiologists, hematologists, and other physicians by convening national and international visionaries, thought-leaders, and dedicated clinician-scientists. This paper summarizes the symposium proceedings.

Genomovar status, virulence markers and genotyping of Burkholderia cepacia complex strains isolated from Brazilian cystic fibrosis patients

Burkholderia cepacia complex isolates obtained by microbiological culture of respiratory samples from Brazilian CF patients were studied by recA based PCR, screened by specific PCR for virulence markers and genotyped by RAPD. Forty-one isolates of B. cepacia complex were identified by culture and confirmation of identity and genomovar determination obtained in 32 isolates, with predominance of B. cenocepacia (53.1%). Virulence markers were not consistently found among isolates. Genotyping did not identify identical patterns among different patients. B. cenocepacia was the most prevalent B. cepacia complex member among our patients, and cross-infection does not seem to occur among them. V 2008 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

Mechanism of ribonuclease inhibition by ribonuclease inhibitor protein based on the crystal structure of its complex with ribonuclease A

We describe the mechanism of ribonuclease inhibition by ribonuclease inhibitor, a protein built of leucine-rich repeats, based on the crystal structure of the complex between the inhibitor and ribonuclease A. The structure was determined by molecular replacement and refined to an R(cryst) of 19.4% at 2.5 Angstrom resolution. Ribonuclease A binds to the concave region of the inhibitor protein comprising its parallel beta-sheet and loops. The inhibitor covers the ribonuclease active site and directly contacts several active-site residues. The inhibitor only partially mimics the RNase-nucleotide interaction and does not utilize the pi phosphate-binding pocket of ribonuclease A, where a sulfate ion remains bound. The 2550 Angstrom(2) of accessible surface area buried upon complex formation may be one of the major contributors to the extremely tight association (K-i = 5.9 x 10(-14) M). The interaction is predominantly electrostatic; there is a high chemical complementarity with 18 putative hydrogen bonds and salt links, but the shape complementarity is lower than in most other protein-protein complexes. Ribonuclease inhibitor changes its conformation upon complex formation; the conformational change is unusual in that it is a plastic reorganization of the entire structure without any obvious hinge and reflects the conformational flexibility of the structure of the inhibitor. There is a good agreement between the crystal structure and other biochemical studies of the interaction. The structure suggests that the conformational flexibility of RI and an unusually large contact area that compensates for a lower degree of complementarity may be the principal reasons for the ability of RI to potently inhibit diverse ribonucleases. However, the inhibition is lost with amphibian ribonucleases that have substituted most residues corresponding to inhibitor-binding residues in RNase A, and with bovine seminal ribonuclease that prevents inhibitor binding by forming a dimer. (C) 1996 Academic Press Limited

Repetitive Transcranial Magnetic Stimulation Is Efficacious as an Add-On to Pharmacological Therapy in Complex Regional Pain Syndrome (CRPS) Type I

Single session repetitive transcranial magnetic stimulation (rTMS) of the motor cortex (M1) is effective in the treatment of chronic pain patients but the analgesic effect of repeated sessions is still unknown We evaluated the effects of rTMS in patients with refractory pain due to complex regional pain syndrome (CRPS) type I Twenty three patients presenting CRPS type I of 1 upper limb were treated with the best medical treatment (analgesics and adjuvant medications physical therapy) plus 10 daily sessions of either real (r) or sham (s) 10Hz rTMS to the motor cortex (M1) Patients were assessed daily and after 1 week and 3 months after the last session using the Visual Analogical Scale (VAS) the McGill Pain Questionnaire (MPQ) the Health Survey 36 (SF 36) and the Hamilton Depression (HDRS) During treatment there was a significant reduction in the VAS scores favoring the r rTMS group mean reduction of 4 65 cm (50 9%) against 2 18 cm (24 7%) in the s rTMS group The highest reduction occurred at the tenth session and correlated to improvement in the affective and emotional subscores of the MPQ and SF 36 Real rTMS to the M1 produced analgesic effects and positive changes in affective aspects of pain in CRPS patients during the period of stimulation Perspective This study shows an efficacy of repetitive sessions of high frequency rTMS as an add on therapy to refractory CAPS type I patients It had a positive effect in different aspects of pain (sensory discriminative and emotional affective) It opens the perspective for the clinical use of this technique (C) 2010 by the American Pain Society

A quantitative coronary angiography-matched comparison between a prospective randomised multicentre cutting balloon angioplasty and bare metal stent trial (REDUCE III) and the Rapamycin-Eluting Stent Evaluation At Rotterdam Cardiology Hospital (RESEARCH) study

Aims: There remains significant concern about the long-term safety of drug-eluting stents (DES). However, bare metal stents (BMS) have been used safely for over two decades. There is therefore a pressing need to explore alternative strategies for reducing restenosis with BMS. This study was designed to examine whether IVUS-guided cutting balloon angioplasty (CBA) with BMS could convey similar restenosis rates to DES. Methods and results: In the randomised REstenosis reDUction by Cutting balloon angioplasty Evaluation (REDUCE III) study, 521 patients were divided into four groups based on device and IVUS use before BMS (IVUS-CBA-BMS: 137 patients; Angio-CBA-BMS: 123; IVUS-BA-BMS: 142; and Angio-BA-BMS: 119). At follow-up, the IVUS-CBA-BMS group had a significantly lower restenosis rate (6.6%) than the other groups (p=0.016). We performed a quantitative coronary angiography (QCA) based matched comparison between an IVUS-guided CBA-BMS strategy (REDUCE III) and a DES strategy (Rapamycin-Eluting-Stent Evaluation At Rotterdam Cardiology. Hospital, the RESEARCH study). We matched the presence of diabetes, vessel size, and lesion severity by QCA. Restenosis (>50% diameter stenosis at follow-up) and target vessel revascularisation (TVR) were examined. QCA-matched comparison resulted in 120-paired lesions. While acute gain was significantly greater in IVUS-CBA-BMS than DES (1.65 +/- 0.41 mm vs. 1.28 +/- 0.57 mm, p=0.001), late loss was significantly less with DES than with IVUS-CBA-BMS (0.03 +/- 0.42 mm vs. 0.80 +/- 0.47 mm, p=0.001). However, no difference was found in restenosis rates (IVUS-CBA-BMS: 6.6% vs. DES: 5.0%, p=0.582) and TVR (6.6% and 6.6%, respectively). Conclusions: An IVUS-guided CBA-BMS strategy yielded restenosis rates similar to those achieved by DES and provided an effective alternative to the use of DES.

Blindness as a complication of monobloc frontofacial advancement with distraction

The monobloc frontofacial osteotomy provides aesthetic and functional improvement in the treatment of various craniofacial deformities. This procedure, through highly complex, has had some significant associated complication, such as cerebrospinal fluid leakage, hematoma, infection, and bone resorption. Distraction has been successfully used to gradually elongate bone and soft tissue. This method seems to provide improved results over conventional surgery, with less morbidity. We present a case of a patient with Apert syndrome who underwent monobloc advancement using the Rigid External Device (RED) device and who developed a transient bilateral amaurosis on the fourth postoperative day before distraction. A second procedure was performed to push back the frontal bandeau, maintaining the device in position. The blindness was resolved with this procedure as well as treatment with systemic steroids. The distraction was started thereafter, and the desired improvement was acquired. To our knowledge, this is the first case of transient bilateral amaurosis in a patient undergoing monobloc distraction.

Protein crystallography and examples of its applications in medicinal chemistry

The field of protein crystallography inspires and enthrals, whether it be for the beauty and symmetry of a perfectly formed protein crystal, the unlocked secrets of a novel protein fold, or the precise atomic-level detail yielded from a protein-ligand complex. Since 1958, when the first protein structure was solved, there have been tremendous advances in all aspects of protein crystallography, from protein preparation and crystallisation through to diffraction data measurement and structure refinement. These advances have significantly reduced the time required to solve protein crystal structures, while at the same time substantially improving the quality and resolution of the resulting structures. Moreover, the technological developments have induced researchers to tackle ever more complex systems, including ribosomes and intact membrane-bound proteins, with a reasonable expectation of success. In this review, the steps involved in determining a protein crystal structure are described and the impact of recent methodological advances identified. Protein crystal structures have proved to be extraordinarily useful in medicinal chemistry research, particularly with respect to inhibitor design. The precise interaction between a drug and its receptor can be visualised at the molecular level using protein crystal structures, and this information then used to improve the complementarity and thus increase the potency and selectivity of an inhibitor. The use of protein crystal structures in receptor-based drug design is highlighted by (i) HIV protease, (ii) influenza virus neuraminidase and (iii) prostaglandin H-2-synthetase. These represent, respectively, examples of protein crystal structures that (i) influenced the design of drugs currently approved for use in the treatment of HIV infection, (ii) led to the design of compounds currently in clinical trials for the treatment of influenza infection and (iii) could enable the design of highly specific non-steroidal anti-inflammatory drugs that lack the common side-effects of this drug class.

Reorganization of terminator DNA upon binding replication terminator protein: Implications for the functional replication fork arrest complex

Termination of DNA replication in Bacillus subtilis involves the polar arrest of replication forks by a specific complex formed between the replication terminator protein (RTP) and DNA terminator sites. While determination of the crystal structure of RTP has facilitated our understanding of how a single RTP dimer interacts with terminator DNA, additional information is required in order to understand the assembly of a functional fork arrest complex, which requires an interaction between two RTP dimers and the terminator site. In this study, we show that the conformation of the major B. subtilis DNA terminator, Terl, becomes considerably distorted upon binding RTP. Binding of the first dimer of RTP to the B site of Terl causes the DNA to become slightly unwound and bent by similar to 40 degrees. Binding of a second dimer of RTP to the A site causes the bend angle to increase to similar to 60 degrees. We have used this new data to construct two plausible models that might explain how the ternary terminator complex can block DNA replication in a polar manner, in the first model, polarity of action is a consequence of the two RTP-DNA half-sites having different conformations. These different conformations result from different RTP-DNA contacts at each half-site (due to the intrinsic asymmetry at the terminator DNA), as well as interactions (direct or indirect) between the RTP dimers on the DNA. In the second model, polar fork arrest activity is a consequence of the different affinities of RTP for the A and B sites of the terminator DNA, modulated significantly by direct or indirect interactions between the RTP dimers.

Negative Pressure Therapy for Complex Wounds in Patients with Sickle-Cell Disease: A Case Study

Sickle-cell disease is the most prevalent genetic disease in the Brazilian population. Lower limb ulcers are the most frequent cutaneous complications, affecting 8% to 10% of the patients. These ulcers are usually deep and may take many years to heal. Evidence about the effectiveness of systemic or topical treatment of these wounds is limited, apart from stabilization of the anemia. A 28-year old woman with sickle-cell disease was admitted for treatment of three deep chronic lower leg ulcers. All wounds had tendon exposure and contained firmly adherent fibrin slough. Following surgical debridement and before grafting, the wounds were managed with three different dressings: a rayon and normal saline solution dressing, a calcium alginate dressing covered with gauze, and negative pressure therapy. All three wounds healed successfully and their grafts showed complete integration; only the rayon-dressed wound required a second debridement. The alginate and rayon-dressed wounds recurred after 9 months and required additional skin grafts. Helpful research on managing ulcers in patients with sickle-cell disease is minimal, but the results of this case study suggest that topical treatment modalities may affect outcomes. Research to explore the safety and effectiveness of NPT in patients with sickle-cell wounds is warranted.

Aesthetic Quality of the Nipple-Areola Complex in Breast Reconstruction with a New Local Graft Technique

Reconstruction of the nipple-areola complex (NAC) is the last stage of breast reconstruction and represents the search for symmetry in regard to the contralateral breast. The objective of this study was to present an areola reconstruction technique with local skin graft to improve the texture and aspect of the reconstructed areola, searching for a natural look. This technique was performed on 122 patients who in the period from January 2000 to December 2005 were submitted to nipple and areola reconstruction. Once the position of the new nipple was determined, markings were made for the reconstruction of the areola. Then the external limit of the new areola was incised and the skin was centripetally deepidermized up to 85% of its diameter. After this procedure the detached skin was repositioned in its bed as a graft and sutured with 4.0 mononylon thread. Incisions with an 11-blade scalpel were then made in V and C forms associated with the detachment of this skin of the receptor area along the local graft so that at the end of the healing process they would determine alterations in the areolar texture mimicking the texture of a normal areola. All patients underwent tattooing 3 months after reconstruction of the NAC taking into account the different shades of the contralateral areola and nipple colors. The use of a local skin graft associated with C and V incisions allowed alteration in the texture of the reconstructed areola. The use of different ink shades for tattooing helped to give a tridimensional aspect to this areola. These factors determined a good aesthetic result in these patients. This areola reconstruction using a local skin graft allows change in the areola texture and a tridimensional aspect similar to that of a normal areola without the inconvenience of grafting from a distance.

Pentoxifylline modifies three-dimensional collagen lattice model contraction and expression of collagen types I and III by human fibroblasts derived from post-burn hypertrophic scars and from normal skin

Fibroblasts are thought to be partially responsible for the persisting contractile forces that result in burn contractures. Using a monolayer cell culture and fibroblast populated collagen lattice (FPCL) three-dimensional model we subjected hypertrophic scar and non-cicatricial fibroblasts to the antifibrogenic agent pentoxifylline (PTF - 1 mg/mL) in order to reduce proliferation, collagen types I and III synthesis and model contraction. Fibroblasts were isolated from post-burn hypertrophic scars (HSHF) and non-scarred skin (NHF). Cells were grown in monolayers or incorporated into FPCL`s and exposed to PTF. In monolayer, cell number proliferation was reduced (46.35% in HSHF group and 37.73% in NHF group, p < 0.0001). PTF selectively inhibited collagen III synthesis in the HSHF group while inhibition was more evident to type I collagen synthesis in the NHF group. PTF also reduced contraction in both (HSHF and NHF) FPCL. (C) 2009 Elsevier Ltd and ISBI. All rights reserved.

A peptide-binding motif for I-A(g7), the class II major histocompatibility complex (MHC) molecule of NOD and Biozzi AB/H mice

The class II major histocompatibility complex molecule I-A(g7) is strongly linked to the development of spontaneous insulin-dependent diabetes mellitus (IDDM) in non obese diabetic mice and to the induction of experimental allergic encephalomyelitis in Biozzi AB/H mice. Structurally, it resembles the HLA-DQ molecules associated with human IDDM, in having a non-Asp residue at position 57 in its beta chain. To identify the requirements for peptide binding to I-A(g7) and thereby potentially pathogenic T cell epitopes, we analyzed a known I-A(g7)-restricted T cell epitope, hen egg white lysozyme (HEL) amino acids 9-27. NH2- and COOH-terminal truncations demonstrated that the minimal epitope for activation of the T cell hybridoma 2D12.1 was M12-R21 and the minimum sequence for direct binding to purified I-A(g7) M12-Y20/K13-R21. Alanine (A) scanning revealed two primary anchors for binding at relative positions (p) 6 (L) and 9 (Y) in the HEL epitope. The critical role of both anchors was demonstrated by incorporating L and Y in poly(A) backbones at the same relative positions as in the HEL epitope. Well-tolerated, weakly tolerated, and nontolerated residues were identified by analyzing the binding of peptides containing multiple substitutions at individual positions. Optimally, p6 was a large, hydrophobic residue (L, I, V, M), whereas p9 was aromatic and hydrophobic (Y or F) or positively charged (K, R). Specific residues were not tolerated at these and some other positions. A motif for binding to I-A(g7) deduced from analysis of the model HEL epitope was present in 27/30 (90%) of peptides reported to be I-A(g7)-restricted T cell epitopes or eluted from I-A(g7). Scanning a set of overlapping peptides encompassing human proinsulin revealed the motif in 6/6 good binders (sensitivity = 100%) and 4/13 weak or non-binders (specificity = 70%). This motif should facilitate identification of autoantigenic epitopes relevant to the pathogenesis and immunotherapy of IDDM.