Cryopreserved and frozen hyaline cartilage imaged by environmental scanning electron microscope. An experimental and prospective study

OBJECTIVE: To obtain images of the articular surface of osteochondral grafts (fresh, frozen, and cryopreserved in RPMI) using an environmental scanning electron microscope (ESEM). To evaluate and compare the main morphological aspects of the chondral surface of the fresh, frozen, and cryopreserved grafts as visualized via ESEM. METHODS: The study was based on osteochondral fragments from the internal condyle of the knee joint of New Zealand rabbits, corresponding to the chondral surface from fresh, frozen, and cryopreserved samples. One hundred ESEM images were obtained from each group and then classified according to a validated system. The kappa index and the corresponding concordance index were calculated, and the groups were compared by Pearson's chi-squared test (p < 0.05). RESULTS: The articular surface of cryopreserved osteochondral grafts had fewer even surfaces and filled lacunae and a higher number of empty lacunae as compared to fresh samples; these differences correspond to images of cell membrane lesions that lead to destruction of the chondrocyte. Frozen grafts showed more hillocky and knobby surfaces than did fresh grafts; they also had a greater number of empty chondrocyte lacunae. CONCLUSION: ESEM is useful for obtaining images of the surface of osteochondral grafts. When compared to fresh samples, cryopreservation in RPMI medium produces changes in the surface of hyaline cartilage, but to a lesser extent than those produced by freezing.     

Recombinant erythropoietin found in seized blood bags from sportsmen

During an anti-doping investigation, the Spanish Guardia Civil confiscated blood bags from elite sportsmen. A novel immuno-purification method demonstrated that plasma samples with elevated erythropoietin (EPO) contained recombinant material (rEPO). This shows that rEPO is used before autologous blood transfusions and that rEPO analysis in plasma can be reliably addressed.     

Iron porphyrinate Fe(TPPS) reduces brain cell damage in rats intrastriatally lesioned by quinolinate

It has been recently demonstrated that the reactive nitrogen species (RNS) peroxynitrite (ONOO⁻) is involved in the neurotoxic pattern produced by quinolinic acid in the rat brain [V. Pérez-De La Cruz, C. González-Cortés, S. Galván-Arzate, O.N. Medina-Campos, F. Pérez-Severiano, S.F. Ali, J. Pedraza-Chaverrí, A. Santamaría, Excitotoxic brain damage involves early peroxynitrite formation in a model of Huntington's disease in rats: protective role of iron porphyrinate 5,10,15,20-tetrakis (4-sulfonatophenyl)porphyrinate iron (III), Neuroscience 135 (2005) 463–474.]. The aim of this work was to investigate whether ONOO⁻ can also be responsible for morphological alterations and inflammatory events in the same paradigm. For this purpose, we evaluated the effect of a pre-treatment with the iron porphyrinate Fe(TPPS), a well-known ONOO⁻ decomposition catalyst (10 mg/kg, i.p., 120 min before lesion), on the quinolinate-induced striatal cell damage and immunoreactivities to glial–fibrilar acidic protein (GFAP), interleukin 6 (IL-6) and inducible nitric oxide synthase (iNOS), one and seven days after the intrastriatal infusion of quinolinate (240 nmol/µl) to rats. The striatal tissue from animals lesioned by quinolinate showed a significant degree of damage and enhanced immunoreactivities to GFAP, IL-6 and iNOS, both at 1 and 7 days post-lesion. Pre-treatment of rats with Fe(TPPS) significantly attenuated or prevented all these markers at both post-lesion times tested, except for GFAP immunoreactivity at 7 days post-lesion and iNOS immunoreactivity at 1 day post-lesion. Altogether, our results suggest that ONOO⁻ is actively participating in triggering inflammatory events and morphological alterations in the toxic model produced by quinolinate, since the use of agents affecting its formation, such as Fe(TPPS), are effective experimental tools to reduce the brain lesions associated to excitotoxic and oxidative damage.     

Trophic interactions between the toxic dinoflagellate Alexandrium catenella and Mytilus chilensis: feeding and digestive behaviour to long-term exposure

Trophic interactions between Mytilus chilensis and the toxic dinoflagellate Alexandrium catenella were studied over a 21-day period to determine the absorption kinetics of biochemical components and the enzymatic activity of the digestive gland (i.e. amylase, cellulase complex, laminarinase and protease). For the duration of the experiment, logarithmic relationships were established for the assimilatory balance and carbohydrase activities (amylase, laminarinase and cellulase) of the mussels fed with a toxic diet. The study shows that M. chilensis was able to develop mechanisms which allow exploitation of the toxic microalgae as a food source, despite that its feeding and digestive processes were affected during the first days of contamination.     

Detection of “Candidatus Rickettsia wissemanii” in ticks parasitizing bats (Mammalia: Chiroptera) in the northern Brazilian Amazon

A total of 482 bats representing 32 species and two families were captured in the Amazon forests of the Amapá state in northern Brazil. Nineteen Artibeus planirostris bats (3.9 %) were infested with 160 ticks, all identified as Ornithodoros hasei. Three pools of larvae were screened for rickettsial DNA via polymerase chain reaction (PCR) targeting three rickettsial genes: gltA, ompA and htrA. Only one of them yielded an amplicons of the expected size for all three molecular assays. Comparisons of the obtained sequences including a phylogenetic analysis confirmed the occurrence of “Candidatus Rickettsia wissemanii” in Brazil.

     

Comparative study between children with and without cleft lip and cleft palate, part 1: cephalometric analysis.

OBJECTIVE: This study was conducted to compare craniofacial relationships, position, and curvature of the cervical spine between children with cleft lip and cleft palate who had been operated on and children without clefts. METHOD: This study was performed in 28 children with mixed dentition. They were divided into two groups. The study group included 14 children with unilateral operated cleft lip and cleft palate, ranging in age from 6 to 12 years, who clinically presented with a short upper lip, abnormal lip seal, and inhibition of sagittal development of the midface that was radiographically assessed. The control group included 14 children without clefts, ranging in age from 8 to 11 years. All of them had normal lip seal, nasal breathing, and a clinically normal body posture. DESIGN: A lateral craniocervical radiograph in a self-balanced natural head position in an erect posture, and without using a head holder, was taken for each child of both groups, with the mandible in maximum intercuspation and lips in habitual posture. The true vertical was marked on all the films. Specific angular and linear dimensions were used to assess the craniocervical relationships, as were the position of the cervical spine, its curvature, or both. RESULTS AND CONCLUSIONS: The study group presented a significant increase in the extension of the head on the neck, forward position of the cervical spine, and a decrease in the curvature of the cervical spine in comparison with the children without clefts. These results are more relevant considering that the study group also presented higher significant values of lower facial height than children without clefts.