Increase of mitochondrial DNA content and transcripts in early bovine embryogenesis associated with upregulation of mtTFA and NRF1 transcription factors

Background  

Recent work has shown that mitochondrial biogenesis and mitochondrial functions are critical determinants of embryonic development. However, the expression of the factors controlling mitochondrial biogenesis in early embryogenesis has received little attention so far.     

Chromosomal diversification of reef fishes from genus <Emphasis Type="Italic">Centropyge</Emphasis>(Perciformes,Pomacanthidae)

The genus Centropyge is remarkable for species richness, composing a highly specialized fish group amongst members from family Pomacanthidae. However, cytogenetical reports are nearly absent in these animals. New data are provided from karyotypical studies carried out on Centropyge aurantonotus from the Brazilian coast of the Atlantic Ocean and C. ferrugatus from the Philippines Sea of the Indo-Pacific Ocean. Both species present 2n=48 but karyotypes are differentiated by fundamental number. C. aurantonotus has a great number of biarmed chromosomes (4 m + 14 sm+16 st+4 a), while C. ferrugatus presents only acrocentric chromosomes. Single nucleolar organizer regions (NORs) are located at interstitial position of an acrocentric pair in C. ferrugatus and on short arms of a subtelocentric pair in C. aurantonotus, as confirmed by fluorescent in situ hybridization (FISH) with 18S rDNA probes. Heterochromatin is distributed over NOR and centromeric regions in both species, but additional GC-rich heterochromatic blocks on short arms of up to eight chromosomal pairs can be detected in C. aurantonotus. 5S rDNA segments were located interstitially on two chromosomal pairs in C. ferrugatus and on nine pairs in C. aurantonotus, mostly equivalent to heterochromatic blocks on short arms of biarmed chromosomes. C. ferrugatus can be considered a species in which basal chromosomal features proposed for modern Teleosteans were conserved. The derived karyotype pattern of C. aurantonotus seems to be determined by pericentric inversions and heterochromatin addition which probably determined the notorious dispersion of 5S rRNA (pseudo)genes. It is demonstrated that, even within a group generally characterized by cytogenetical homogeneity as the family Pomacanthidae, diversified karyotypes can be found.     

Assessment of micronucleus frequency in normal oral mucosa of patients exposed to carcinogens

OBJECTIVE: To assess the presence of micronuclei in exfoliated oral mucosal cells collected from 3 anatomic sites in patients exposed to tobacco and alcohol. STUDY DESIGN: Smears were prepared with normal oral mucosal cells obtained from the lower lip, tongue border and floor of the mouth of 21 controls, 28 tobacco users and 19 tobacco/alcohol users. Slides were stained with Feulgen stain for quantification of micronucleated cells, karyorrhexis and "broken eggs." RESULTS: The groups were similar in terms of the mean number of micronucleated cells and cells undergoing karyorrhexis. In the comparison of anatomic sites, the mean number of cells undergoing karyorrhexis was higher on the lower lip than on the tongue border or floor of the mouth (all groups). A significantly higher number of broken eggs was observed in the control group when compared to the tobacco and tobacco/alcohol groups at all anatomic sites. CONCLUSION: The higher number of broken eggs in patients not exposed to tobacco and/or alcohol suggests that this nuclear alteration may be associated with DNA repair or a healthy mucosa. A trend toward an increased number of micronucleated cells was observed for tobacco and/or alcohol users at all anatomic sites.     

Casearin X exhibits cytotoxic effects in leukemia cells triggered by apoptosis

Clerodane diterpenes have demonstrated cytotoxic, antiplasmodial and anti-ulcer properties. In the present work, we determined the cytotoxic effect of casearin L (Cas L), O (Cas O) and X (Cas X) and (?)-hardwickiic acid isolated from Casearia sylvestris leaves, and investigated the underlying mechanisms involved in in vitro cell death induced by Cas X in HL-60 leukemia cells (0.7, 1.5 and 3.0 μM). Cytotoxicity tests demonstrated that Cas X was the most active compound studied, showing greater cytotoxic effects against CEM and HL-60 lines (IC₅₀ of 0.4 μM) and human peripheral blood mononuclear cells (PBMC, IC₅₀ of 1.2 μM). After 24 h exposure, Cas X caused a decrease in 5-bromo-20-deoxyuridine (BrdU) incorporation (36.6 and 24.5% labeling at 0.7 and 1.5 μM, respectively), reduction in viability, and increase in apoptotic and necrotic leukemia cells in a dose-dependent manner evidenced by the trypan blue and AO/EB (acridine orange/ethidium bromide) assays. Moreover, Cas X-treated cells exhibited nuclear fragmentation and cytoplasmic vacuolization depending on the concentration tested. These characteristics of apoptosis or secondary necrosis were confirmed by flow cytometry which revealed DNA fragmentation, phosphatidylserine externalization, activation of the effector caspases 3/7 and mitochondrial depolarization. We then found evidence that Cas X causes cell death via apoptotic pathways, corroborating the potential of casearins as compounds with promising antitumor-related properties.     

Pregnancy in Squaliolus laticaudus (Elasmobranch: Dalatiidae) from Brazil

Synopsis A pregnant female of the Dwarf deep-sea shark, Squaliolus laticaudus with four embryos was caught by the nocturnal longline vessel “Progress?o” from southern Brazil, on September 1999. It was donated by the fishermen. Embryos ranged in size 105 – 100 mm of total length. The aim of this article is to contribute to the knowledge of the Dwarf deep-sea shark reproduction and distribution on the Brazilian coast. It is been considered the first record to know about pregnant Dwarf deep-sea shark in the world.     

Biomphalaria tenagophila: dynamics of populations of resistant and susceptible strains to Schistosoma mansoni, with or without pressure of the parasite

Resistant (Taim, RS) and susceptible albino (Joinville, SC) Biomphalaria tenagophila populations were kept together, at different proportions, throughout a 18-month-period. Some of the snail groups were submitted to Schistosoma mansoni infection. The targets of this study were (a) to analyze the populational dynamics among resistant and susceptible individuals to S. mansoni; (b) to study the resistance phenotype in descendants of cross-breeding; (c) to observe whether the parasite could exert any kind of selection in those snail populations. Throughout the experiment it could be observed that the susceptible B. tenagophila strain (Joinville) underwent a selective pressure of the parasite that was negative, since the individuals showed a high mortality rate. Although B. tenagophila (Taim) population presented a higher mortality rate without pressure of the parasite, this event was compensated by a reproductive capacity. B. tenagophila Taim was more fecund than B. tenagophila Joinville and was able to transmit the resistance character to their descendants. F1 generation obtained by cross-breeding between resistant and susceptible lineages was completely resistant to S. mansoni infection, irrespective of the Taim proportion. Moreover, less than 5% of F2 progeny were susceptible to S. mansoni infection.     

Polysaccharide isolated from Passiflora edulis: Characterization and antitumor properties

A hot water-extracted polysaccharide fraction (PFCM) of Passiflora edulis was characterized by microanalysis, infrared spectroscopy, NMR and high performance size-exclusion chromatography. The major component in PFCM is (1 → 4) linked galacturonic acid (esterified and unesterified). Neutral sugars such as arabinose, glucose, rhamnose, mannose, and fucose were also present. Traces of xylose and ribose were detected. The PFCM sample had a similar molar mass to that of pectin extracted from P. edulis under acidic conditions. Sarcoma 180 tumors treated with PFCM showed a growth inhibition ratio ranging from 40.59% to 48.73% depending on the dosage and type of PFCM administration (oral or intraperitoneal). Toxicological analysis shows that PFCM increases the cell types involved in primary defense mechanisms and no significant changes in the biochemical parameters and organs (e.g., kidney and liver) were observed. However, the use of PFCM treatment increased the spleen weight when compared with the use of 5-fluorouracil.     

Genome sequences of the ethanol-tolerant Lactobacillus vini strains LMG 23202T and JP7.8.9

We report on the genome sequences of Lactobacillus vini type strain LMG 23202(T) (DSM 20605) (isolated from fermenting grape musts in Spain) and the industrial strain L. vini JP7.8.9 (isolated from a bioethanol plant in northeast Brazil). All contigs were assembled using gsAssembler, and genes were predicted and annotated using Rapid Annotation using Subsystem Technology (RAST). The identified genome sequence of LMG 23202(T) had 2.201.333 bp, 37.6% G+C, and 1,833 genes, whereas the identified genome sequence of JP7.8.9 had 2.301.037 bp, 37.8% G+C, and 1,739 genes. The gene repertoire of the species L. vini offers promising opportunities for biotechnological applications.     

Central poststroke pain: somatosensory abnormalities and the presence of associated myofascial pain syndrome

Background

Mild cognitive impairment (MCI), defined as a transitional zone between normal cognition and dementia, requires a battery of formal neuropsychological tests administered by a trained rater for its diagnosis. The objective of this study was to develop a screening tool for MCI.

Methods

One hundred ninety seven cognitively normal controls (NC), one hundred sixteen patients with amnestic MCI ?Csingle domain (aMCI-sd), one hundred ninety five patients with amnestic MCI-multiple domain (aMCI-md), and two hundred twenty eight patients with mild Alzheimer??s disease (AD) were evaluated by comprehensive neuropsychological tests and by the Memory and Executive Screening (MES).

Results

Correlation analysis showed that the three indicators of the MES were significantly negatively related with age (P<0.05), yet not related with education (P>0.05). There was no ceiling or floor effect. Test completion averaged seven minutes (421.14±168.31 seconds). The receiver operating characteristics (ROC) analyses performed on the aMCI-sd group yielded 0.89 for the area under the curve (AUC) (95% CI, 0.85?C0.92) for the MES-total score, with sensitivity of 0.795 and specificity of 0.828. There was 81% correct classification rate when the cut-off was set at less than 75. Meanwhile, the aMCI-md group yielded 0.95 for the AUC (95% CI, 0.93?C0.97) for the MES-total score, with sensitivity of 0.87 and specificity of 0.91, and 90% correct classification rate when the cut-off was set at less than 72.

Conclusion

The MES, minimally time-consuming, may be a valid and easily administered cognitive screening tool with high sensitivity and specificity for aMCI, with single or multiple domain impairment.