Hantavirus pulmonary syndrome in Uberaba,Minas Gerais,Brazil

This report describes the epidemiological and clinical-evolutive characteristics of eight patients with hantavirus pulmonary syndrome (HPS) in Uberaba, Minas Gerais, Brazil. A positive history of contact with rodents was present in 100% of the cases. The time between the onset of symptoms and hospital care was, on average, 3.6 days. All patients showed clinical and laboratory findings suggestive of HPS. Elevated urea and creatinine levels were observed in 6 (75%) cases, PO2 was < 60 mmHg in 100% of the cases, and a chest X-ray demonstrated a bilateral interstitial-alveolar infiltrate. The diagnosis was confirmed by the detection of IgM antibodies against Sin Nombre virus by ELISA. Three patients died as a direct consequence of HPS.     

In vitro tests for haematotoxicity: prediction of drug-induced myelosuppression by the CFU-GM assay

In a prevalidation study, a standard operating procedure (SOP) for human and mouse in vitro tests was developed, for evaluating the potential haematotoxicity of xenobiotics in terms of their direct, adverse effects on the myeloid colony-forming unit (CFU-GM). Based on the adjustment of the mouse-derived maximum tolerated dose (MTD), a prediction model was set up to calculate the human MTD, and an international blind trial was designed to apply this model to the clinical neutropenia of 23 drugs including 17 antineoplastics. The model correctly predicted the human MTD for 20 drugs out of the 23 (87%). This high percentage of predictivity, and the reproducibility of the SOP testing, confirmed the scientific validation of this model, and suggest promising applications for developing and validating other in vitro methods for use in haematotoxicology.     

Transition metals and carbohydrates: the methyl-4,6-O-benzylidene-2,3-diazo-2,3-dideoxy-alpha-D-mannopyranoside skeleton as building block for new chiral nitrogen chelates

This paper describes a straightforward strategy for the synthesis of new nitrogen chelates by employing the chirality of readily available sugars. Thus, diimino and diamino ligands can be attained easily by using the methyl-4,6-O-benzylidene-2,3-diazo-2,3-dideoxy-alpha-D-mannopyranoside skeleton. The coordinating ability of one ligand has also been assessed by preparing a square-planar palladium complex [PdCl2(N,N-chelate)].     

Allium archeotrichon (Alliaceae), a new species from Rhodos (Dodekannìsos, Greece)

Allium archeotrichon , an autumnal geophyte occurring in rocky places on the island of Rhodos, is described as new to science and illustrated. Its karyology, ecology, leaf anatomy and taxonomic relationships are discussed.     

Hemispheric asymmetries in cortical electrical activity during sleep. I

The hypothesis of a predominance of the right hemisphere in stage REM as compared to NREM has been tested through a spectral analysis of the EEG recorded from left (T3) and right (T4) temporal sites in 5 young healthy right-handed male subjects. Variations in the asymmetry coefficient R - L/R + L in different sleep stages have been analyzed by one way ANOVAs and Sheffé's tests. The hypothesis of a progressive increase in left hemisphere activity throughout different REM cycles as one approaches final awakenings have been investigated by comparing variations in the asymmetry coefficient for epochs of REM and stage 2 NREM sampled in different phases of the REM cycle. EEG results do not support either the hypothesized stage dependent or cycle dependent variation in EEG activity during sleep. We question whether variations in EEG amplitude and synchronization can be used as indices of hemispheric asymmetries during sleep.     

The p53-induced Wig-1 protein binds double-stranded RNAs with structural characteristics of siRNAs and miRNAs

Wig-1 is a p53-induced zinc finger protein. Here we show that human Wig-1 binds long (>or=23 bp) dsRNAs with 5'-overhangs. The first zinc finger domain is necessary but not sufficient for this dsRNA-binding in vitro. Wig-1 also binds dsRNA in living cells via zinc fingers 1 and 2. Both zinc fingers 1 and 2 are important for Wig-1-mediated growth suppression. Moreover, Wig-1 binds 21 bp dsRNAs with 3'-protruding ends. These findings demonstrate that human Wig-1 can bind different types of dsRNAs, including dsRNAs resembling small interfering RNAs (siRNAs) and microRNAs (miRNAs), and indicate that dsRNA binding has a role in Wig-1-mediated regulation of cell growth.     

Structural characterization of novel chitin-binding lectins from the genus Artocarpus and their antifungal activity

Two novel chitin-binding lectins from seeds of Artocarpus genus were described in this paper, one from A. integrifolia (jackfruit) and one from A. incisa (breadfruit). They were purified from saline crude extract of seeds using affinity chromatography on chitin column, size-exclusion chromatography and reverse-phase chromatography on the C-18 column. Both are 14 kDa proteins, made up of 3 chains linked by disulfide bonds. The partial amino acid sequences of the two lectins showed they are homologous to each other but not to other plant chitin-binding proteins. Thus, they cannot be classified in any known plant chitin-binding protein family, particularly because of their inter-chain covalent bonds. Their circular dichroism spectra and deconvolution showed a secondary structure content of beta-sheet and unordered elements. The lectins were thermally stable until 80 degrees C and structural changes were observed below pH 6. Both lectins inhibited the growth of Fusarium moniliforme and Saccharomyces cerevisiae, and presented hemagglutination activity against human and rabbit erythrocytes. These lectins were denoted jackin (from jackfruit) and frutackin (from breadfruit).     

The induction of NOS2 expression by the hybrid cecropin A-melittin antibiotic peptide CA(1-8)M(1-18) in the monocytic line RAW 264.7 is triggered by a temporary and reversible plasma membrane permeation

There is an increasing awareness of immune cell modulation by antimicrobial peptides. While this process often requires specific receptors for the peptides involved, several reports point out to a receptor-independent process. The cecropin A-melittin hybrid peptide CA(1-8)M(1-18) (KWKLFKKIGIGAVLKVLTTGLPALIS-amide) modifies gene expression in the macrophage line RAW 264.7 in the absence of any previous macrophage priming, suggesting a membrane permeation process. To further analyze the initial steps of this mechanism, we have studied the interaction of the peptide with these cells. Below 2 microM, CA(1-8)M(1-18) causes a concentration-dependent membrane depolarization partially reversible with time. At 2 microM, the accumulation of the SYTOX green vital dye is one half of that achieved with 0.05% Triton X-100. The binding level, as assessed by fluorescein-labeled CA(1-8)M(1-18), varies from 7.7+/-1.2 to 37.4+/-3.9 x 10(6) molecules/cell over a 0.5-4.0 microM concentration range. Electrophysiological experiments with 0.5 microM CA(1-8)M(1-18), a concentration that triggers maximal NOS2 expression and minimal toxicity, show a reversible current induction in the RAW 264.7 plasma membrane that is maintained as far as peptide is present. This activation of the macrophage involves the production of nitric oxide, a metabolite lethal for many pathogens that results from unspecific membrane permeation by antimicrobial peptides, and represents a new mode of action that may open new therapeutic possibilities for these compounds against intracellular pathogens.     

Continuous enzymatic transesterification of sesame oil and a fully hydrogenated fat: effects of reaction conditions on product characteristics

An immobilized lipase from Thermomyces lanuginosus (TL IM) was employed to mediate the continuous transesterification of sesame oil and fully hydrogenated soybean oil (FHSBO) in a packed-bed reactor operating at 70 degrees C. Reactions between sesame oil (rich in LLL (15.97%), LOL (31.56%), and OLO (21.15%) [L = linoleic; O = oleic]) and the fully hydrogenated fat ((73.7% SSS, 26.3% SPS) [S = stearic; P = palmitic]) produced semi-solid fats. These products are complex mixtures of triacylglycerol (TAG) species whose compositions depend on reaction conditions. The dependence of the steady state product TAG profile on space time was determined for four initial weight ratios of sesame oil to hydrogenated fat (90:10, 80:20, 70:30, and 60:40). Except for the trial involving a weight ratio of sesame oil to FHSBO of 60:40, near equilibrium conditions were achieved at space times of 30 min-1 h. The chemical, physical, and functional properties of the product semi-solid fats were characterized. The predominant TAG species in the quasi-equilibrium products obtained from the mixture initially containing 90% (w/w) sesame oil and 10% FHSBO were LOL (26.22%) and OLO (21.92%). For transesterification of 80% sesame oil and 20% FHSBO, the major product species were OOP (21.27%), LOL (17.46%), and OLO (13.93%). OOP (24.38%) was the major product for reaction of 70% sesame oil with 30% FHSBO. Appropriate choices of reaction conditions and initial ratios of sesame oil to FHSBO lead to TAG with melting profiles and solid fat contents (SFC) similar to those of a variety of commercial products.