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During an 8-year study period, Arcobacter butzleri was the fourth most common Campylobacter-like organism isolated from 67,599 stool specimens. Our observations suggest that A. butzleri displays microbiologic and clinical features [...]

Biomass and photosynthetic pigments production of cyanobacteria, in particular Spirulina (Arthrospira platensis), depend on light intensity. Production cost of Spirulina cultivation in photobioreactor illuminated with LED is strongly related to light cost. This work is aimed to evaluate the effects of light intensity and photoperiod on the energy efficiency of biomass and pigment production of Spirulina platensis UTEX 1926. Cultures illuminated with white light-emitting diodes (LED) were carried out in batch mode cultivation. Three lighting scenarios with different light intensities were tested: two with a constant light intensity at 80 and 160 μmol · m−2 · s−1 and one with modulated light intensity. Concerning photoperiod, three cycles of light:dark (h:h) (24:00, 20:04 and 16:08) were studied under light intensity at 160 μmol · m−2 · s−1. Concerning Spirulina biomass and pigment production (phycocyanin, chlorophyll and carotenoids), it is found that the lower intensity tested allows a substantial increase of the process energy efficiency. Concerning the influence of the photoperiod, it has been found that the longer the off time is (up to 08 h 00 a day), the higher is the energy efficiency for Spirulina biomass as well as for pigmentary production.

Research on lipid production in microalgae, especially to target biofuels, has been widely published in recent decades. This literature is mostly focused on the optimization of culture conditions, metabolic engineering, biorefinery and downstream processes. At the lab scale, lipid production is very promising concerning biofuels production based on microalgae due to their high lipid content. However, the accumulation of knowledge associated with the development of processes and technologies for the production of biomass and associated lipids has so far not achieved the hoped-for commercial success due to still too expensive operating costs compared to fossil fuels. This review aims to present the influence of various abiotic factors on the accumulation of lipids and lipid profile in microalgae, such as the depletion of the culture medium, temperature and light, but also most innovative like the induction by hormones. Other optimization procedures and the use of wastewater to improve the cost-viability are discussed in perspective.

Electron microscopy, immune electron microscopy and complement fixation as methods of detecting rotavirus in the stools of young children with gastroenteritis were compared in a blind study during the winter of 1975-6. Complement fixation was the simplest to perform, was as sensitive as the other two, and allowed a quantitative measurement of viral excretion. Absorption of faecal extracts with fetal calf serum usually removed the anticomplementary activity of faecal extracts. [ABSTRACT FROM PUBLISHER]

Corneal diseases cause severe visual impairment that necessitates corneal transplantation and frequently repetitive procedures due to graft rejection. We tested the hypothesis that exposure of donor corneas to recipient serum-derived factors during eye banking triggers a preoperative adaptation that is beneficial for postoperative tolerance. Donor corneas were incubated in a medium containing human serum (HS) obtained in each case from the prospective graft recipient in order to individually expose the donor cornea to the recipient's serum. All recipient serum-adapted corneas (RSACs) fulfilled the clinical criteria required by the national law and were transplanted successfully. The postoperative ophthalmological examination extended up to 8 years. All RSACs were tolerated by their recipients and did not cause postoperative complications and no rejection. Proteomic analysis of corneas cultivated in culture medium containing either fetal calf serum (FCS) that is routinely used for cornea banking or HS revealed different patterns of proteins. HS-cultured corneas showed a greater proteomic similarity with native human corneas than did the FCS-cultured corneas, indicating a differential nutrification of the cultured corneal tissue by HS-derived factors. The clinical results show for the first time that postoperative complications such as tissue intolerance and graft rejection might be managed if the corneal tissue is individually adapted to the recipient's serum trophic factors. This new donor tissue treatment procedure offers incontrovertible advantages and could be adapted for low-risk eyes as well as other transplantable tissues.

Objectives: To describe the clinical and microbiological features of Dientamoeba fragilis and Giardia lamblia infected patients, and to analyze the genetic variation of D. fragilis strains., Methods: For a period of two years, all stool samples collected from patients suspected of having a parasitic gastrointestinal infection were examined according to our specific triple feces test (TFT) protocol. A retrospective case-control study was performed on D. fragilis and G. lamblia infected patients. Furthermore, PCR and genotyping by restriction fragment length polymorphism (RFLP) were performed upon the former., Results: D. fragilis (6.3%) and G. lamblia (7.1%) were the most common pathogenic protozoa isolated out of 448 patients studied. Symptoms most frequently encountered with D. fragilis and G. lamblia infection were abdominal pain (69.2% and 72.4%, respectively) and diarrhea (61.5% and 79.3%, respectively). However, patients with D. fragilis infections suffered significantly less frequently from nausea and/or vomiting, anorexia and weight loss. After treatment, all D. fragilis and G. lamblia infected patients presenting a negative TFT follow-up also reported a complete resolution of their symptoms. Only genotype 1 could be detected in D. fragilis infected patients., Conclusions: D. fragilis and G. lamblia were the most frequently encountered parasites in our study population. Improved diagnostic tests are essential tools to study the prevalence and pathogenesis of D. fragilis.