Crithidia ricardoi sp. n. a new species of trypanosomatidae isolated from Culex saltanensis Dyar, 1928 (Diptera: Culicidae)

A flagellte trypanosomatid was isolated in culture from the digestive tract of the mosquito Culex saltanensis Dyar, 1928. It grows exuberantly in liver infusion in the form of epimastigotes and choanomastigotes typical of the genus Crithidia. The trypanosomatid was compared to C. deanei, C. fasciculata, C. luciliae, C. oncopelti and C. guilhermei. The techniques used for comparison were electron transmission microscopy, isoenzymes and kDNA restriction profiles. No endosymbionts were found at electron microscopy. Results for the biochemical methods employd indicate that the trypanosomatid isolated from C. saltanensis is a new species of Crithidia. The name C. ricardoi sp. n. is proposed for thes new species.

Techniques for analytical testing of unconventional samples.

Forensic scientists have long detected the presence of drugs and their metabolites in biological materials using body fluids such as urine, blood and/or other biological liquids or tissues. For doping analysis, only urine has so far been collected. In recent years, remarkable advances in sensitive analytical techniques have encouraged the analysis of drugs in unconventional biological samples such as hair, saliva and sweat. These samples are easily collected, although drug levels are often lower than the corresponding levels in urine or blood. This chapter reviews recent studies in the detection of doping agents in hair, saliva and sweat. Sampling, analytical procedures and interpretation of the results are discussed in comparison with those obtained from urine and blood samples.

Failure of vancomycin continuous infusion against experimental endocarditis due to vancomycin-intermediate Staphylococcus aureus.

Continuous infusion of vancomycin was evaluated against experimental endocarditis due to heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA) and VISA. Animals were infected with hVISA PC1 (vancomycin MIC, 2 mg/liter) or VISA PC3 (vancomycin MIC, 8 mg/liter) and treated for 5 days with constant serum levels of 20 or 40 mg/liter. Vancomycin continuous infusion was unsuccessful, as 20 mg/liter was barely active against PC1 (6 of 13 sterile vegetations) and 40 mg/liter failed against PC3 (2 of 9 sterile vegetations).

Protein recovery, separation and purification: selection of optimal techniques using an expert system

The paper discusses the utilization of new techniques ot select processes for protein recovery, separation and purification. It describesa rational approach that uses fundamental databases of proteins molecules to simplify the complex problem of choosing high resolution separation methods for multi component mixtures. It examines the role of modern computer techniques to help solving these questions.

Infusion of atrial natriuretic peptide to patients with congestive heart failure.

Atrial natriuretic peptides (ANP) exert vasodilating and natriuretic actions. The present study was undertaken to test the effect of low dose infusions of synthetic ANP on hemodynamic and humoral variables of patients with severe heart failure. Eight patients, aged 26 to 71 years, with severe congestive heart failure due to ischemic heart disease or idiopathic dilated cardiomyopathy were included in the study. Synthetic human (3-28) ANP was infused at doses ranging from 0.5 to 2 micrograms/min for up to 3 h. Pulmonary capillary wedge pressure fell from 24 +/- 1 to 16 +/- 2 mm Hg (mean +/- SEM) (p less than 0.01) and cardiac index tended to rise from 2 +/- 0.2 to 2.3 +/- 0.2 L/min/m2 (NS), while blood pressure and heart rate did not change. One patient experienced a marked drop in pulmonary capillary wedge and arterial blood pressure that necessitated the administration of saline. ANP infusion did not alter plasma renin activity or plasma aldosterone, norepinephrine, or vasopressin levels. It decreased plasma epinephrine levels from 0.472 +/- 0.077 to 0.267 +/- 0.024 nmol/L (p less than 0.05). Plasma ANP levels were markedly elevated in all patients before initiating the infusion. They had no predictive value for the hemodynamic response to exogenous ANP. No correlation was observed between the hemodynamic effects of ANP and those induced by the subsequently administered converting enzyme inhibitor captopril, which seemed to improve cardiac function more consistently.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of Some Molecular-genetic Techniques for Identification of Leishmania Circulating in Natural Foci of Zoonotic Cutaneous Leishmaniasis in the Central Asia Region

Different molecular-genetic methods were used to identify a cohort of Leishmania strains from natural foci of zoonotic cutaneous leishmaniasis located in Central Asia, on the former USSR territory. The results obtained using isoenzymes, PCR, restriction fragment length polymorphisms of kDNA and molecular hybridization techniques are discussed in terms of their applicability, discrimination power and feasibility for answering questions related to molecular epidemiological research and for detecting mixed Leishmania infections

Optimum in vitro expansion of human antigen-specific CD8 T cells for adoptive transfer therapy.

Increasing evidence suggests that adoptive transfer of antigen-specific CD8(+) T cells could represent an effective strategy in the fight against chronic viral infections and malignancies such as melanoma. None the less, a major limitation in the implementation of such therapy resides in the difficulties associated with achieving rapid and efficient expansion of functional T cells in culture necessary to obtain the large numbers required for intravenous infusion. Recently, the critical role of the cytokines interleukin (IL)-2, IL-7 and IL-15 in driving T cell proliferation has been emphasized, thus suggesting their use in the optimization of expansion protocols. We have used major histocompatibility complex (MHC) class I/peptide multimers to monitor the expansion of antigen-specific CD8 T lymphocytes from whole blood, exploring the effect of antigenic peptide dose, IL-2, IL-7 and IL-15 concentrations on the magnitude and functional characteristics of the antigen-specific CD8(+) T cells generated. We show here that significant expansions of antigen-specific T cells, up to 50% of the CD8(+) T cell population, can be obtained after a single round of antigen/cytokine (IL-2 or IL-15) stimulation, and that these cells display good cytolytic and interferon (IFN)-gamma secretion capabilities. Our results provide an important basis for the rapid in vitro expansion of autologous T cells from the circulating lymphocyte pool using a simple procedure, which is necessary for the development of adoptive transfer therapies.

An approximate mathematical model for solidification of a flowing liquid in a microchannel

A mathematical model is developed to analyse the combined flow and solidification of a liquid in a small pipe or two-dimensional channel. In either case the problem reduces to solving a single equation for the position of the solidification front. Results show that for a large range of flow rates the closure time is approximately constant, and the value depends primarily on the wall temperature and channel width. However, the ice shape at closure will be very different for low and high fluxes. As the flow rate increases the closure time starts to depend on the flow rate until the closure time increases dramatically, subsequently the pipe will never close.

Neuroimaging techniques in Alzheimer's disease

Neuroimaging techniques provide valuable tools for diagnosing Alzheimer's disease (AD), monitoring disease progression and evaluating responses to treatment. There is currently a wide array of techniques available including computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET), and, for recording electrical brain activity, electroencephalography (EEG). The choice of technique depends on the contrast between tissues of interest, spatial resolution, temporal resolution, requirements for functional data and the probable number of scans required. For example, while PET, CT and MRI can be used to differentiate between AD and other dementias, MRI is safer and provides better contrast of soft tissues. Neuroimaging is a technique spanning many disciplines and requires effective communication between doctors requesting a scan of a patient or group of patients and those with technical expertise. Consideration and discussion of the most suitable type of scan and the necessary settings to achieve the best results will help ensure appropriate techniques are chosen and used effectively. Neuroimaging techniques are currently expanding understanding of the structural and functional changes that occur in dementia. Further research may allow identification of early neurological signs ofAD, before clinical symptoms are evident, providing the opportunity to test preventative therapies. CombiningMRI and machine learning techniques may be a powerful approach to improve diagnosis ofAD and to predict clinical outcomes.

Extracellular serine-proteinases isolated from Streptomyces alboniger: Partial characterization and effect of aprotinin on cellular structure

Streptomyces alboniger ATCC 12461 grown in brain heart infusion (BHI) medium produced two extracellular serine-proteinases, denoted SP I and SP II, which were purified by ammonium sulfate precipitation and aprotinin-agarose affinity chromatography. SP I was purified 88,9-fold and SP II 66,7- fold, with 33.4% and 10.4% yield, respectively. The optimum pH for the proteinases activity, using a-N-p-tosyl-L-arginine-methyl ester (TAME) as substrate, was 9-10 and the optimum temperature was 37ºC. The proteolytic activity of SP I and SP II was inhibited by aprotinin and SP I was partially inhibited by leupeptin, both serine-proteinase inhibitors. S. alboniger growth in BHI-liquid medium decreased when 5 mg/ml, 10 mg/ml of aprotinin was used, being completely inhibited with 20 mg/ml and 40 mg/ml. At the ultrastructural level, aprotinin-treated S. alboniger cells showed swelling of the bacterial body and condensation of the genetic material, probably related to the inhibition of its growth.

Liquid line of descent of a basanitic liquid at 1.5 GPa: Constraints for metasomatic vein formation

The metasomatism observed in the oceanic and continental lithosphere is generally interpreted to represent a continuous differentiation process forming anhydrous and hydrous veins plus a cryptic enrichment in the surrounding peridotite. In order to constrain the mechanisms of vein formation and potentially clarify the nature and origin of the initial metasomatic agent, we performed a series of high-pressure experiments simulating the liquid line of descent of a basanitic magma differentiating within continental or mature oceanic lithosphere. This series of experiments has been conducted in an end-loaded piston cylinder apparatus starting from an initial hydrous ne-normative basanite at 1.5 GPa and temperature varying between 1,250 and 980°C. Near-pure fractional crystallization process was achieved in a stepwise manner in 30°C temperature steps and starting compositions corresponding to the liquid composition of the previous, higher-temperature glass composition. Liquids evolve progressively from basanite to peralkaline, aluminum-rich compositions without significant SiO2 variation. The resulting cumulates are characterized by an anhydrous clinopyroxene + olivine assemblage at high temperature (1,250-1,160°C), while at lower temperature (1,130-980°C), hydrous cumulates with dominantly amphibole + minor clinopyroxene, spinel, ilmenite, titanomagnetite and apatite (1,130-980°C) are formed. This new data set supports the interpretation that anhydrous and hydrous metasomatic veins could be produced during continuous differentiation processes of primary, hydrous alkaline magmas at high pressure. However, the comparison between the cumulates generated by the fractional crystallization from an initial ne-normative liquid or from hy-normative initial compositions (hawaiite or picrobasalt) indicates that for all hydrous liquids, the different phases formed upon differentiation are mostly similar even though the proportions of hydrous versus anhydrous minerals could vary significantly. This suggests that the formation of amphibole-bearing metasomatic veins observed in the lithospheric mantle could be linked to the differentiation of initial liquids ranging from ne-normative to hy-normative in composition. The present study does not resolve the question whether the metasomatism observed in lithospheric mantle is a precursor or a consequence of alkaline magmatism; however, it confirms that the percolation and differentiation of a liquid produced by a low degree of partial melting of a source similar or slightly more enriched than depleted MORB mantle could generate hydrous metasomatic veins interpreted as a potential source for alkaline magmatism by various authors.