Assessing the Influence of Different Comorbidities Indexes on the Outcomes of Allogeneic Hematopoietic Stem Cell Transplantation in a Developing Country

Although the application of Hematopoietic Cell Transplantation-specific Comorbidity Index (HCT-CI) has enabled better prediction of transplant-related mortality (TRM) in allogeneic hematopoietic stem cell transplants (AHSCT), data from developing countries are scarce. This study prospectively evaluated the HCT-CI and the Adult Comorbidity Evaluation (ACE-27), in its original and in a modified version, as predictors of post-transplant complications in adults undergoing a first related or unrelated AHSCT in Brazil. Both bone marrow (BM) and peripheral blood stem cells (PBSC) as graft sources were included. We analyzed the cumulative incidence of granulocyte and platelet recovery, sinusoidal obstructive syndrome, acute and chronic graft-versus-host disease, relapse and transplant-related mortality, and rates of event-free survival and overall survival. Ninety-nine patients were assessed. Median age was 38 years (18–65 years); HCT-CI ≥ 3 accounted for only 8% of cases; hematologic malignancies comprised 75.8% of the indications for AHSCT. There was no association between the HCT-CI or the original or modified ACE-27 with TRM or any other studied outcomes after AHSCT. These results show that, in the population studied, none of the comorbidity indexes seem to be associated with AHSCT outcomes. A significantly low frequency of high-risk (HCT-CI ≥ 3) in this Brazilian population might justify these results.     

Active release of microcystins controlled by an endogenous rhythm in the cyanobacterium Microcystis aeruginosa

The active release of microcystins in cyanobacterium Microcystis aeruginosa (Kützing) Kützing, strain BCCUSP232 was confirmed. The microcystin release is controlled by an endogenous rhythm, pointing to a biosynthetic pattern of toxins in cyanobacteria. Proofing tests for this active release were carried out by experiments at two independent 24 h cycles, light : dark and continuous light (12:12 h) along the exponential growing phase. Cultivation samples at light, temperature and photoperiod controlled conditions were collected in 2‐h intervals. Microcystin concentrations from the pellet aliquots (intracellular microcystin per cell‐quota –IMC) and supernatant (extracellular microcystin per equivalent cell‐quota – EMC) were quantified with enzyme linked immunosorbent assay. The IMC concentrations showed increases and decreases in both cycles. Decreases of IMC clearly demonstrate that the toxin was actively released to the surrounding medium and not by cell lysis. The total microcystins concentrations (IMC and EMC) between the light : dark and continuous light cycles presented similar variations between the same hours.     

Development of a new method for simultaneous extraction of chlorophylls and carotenoids from microalgal biomass

Journal of Applied Phycology - There are still limitations in the pigment extraction methods used in microalgae biomass, especially for laboratory scale. This work aimed to develop a simple method...     

Identification of genes required for de novo DNA methylation in Arabidopsis

De novo DNA methylation in Arabidopsis thaliana is catalyzed by the methyltransferase DRM2, a homolog of the mammalian de novo methyltransferase DNMT3. DRM2 is targeted to DNA by small interfering RNAs (siRNAs) in a process known as RNA-directed DNA Methylation (RdDM). While several components of the RdDM pathway are known, a functional understanding of the underlying mechanism is far from complete. We employed both forward and reverse genetic approaches to identify factors involved in de novo methylation. We utilized the FWA transgene, which is methylated and silenced when transformed into wild-type plants, but unmethylated and expressed when transformed into de novo methylation mutants. Expression of FWA is marked by a late-flowering phenotype, which is easily scored in mutant versus wild-type plants. By reverse genetics we discovered the requirement for known RdDM effectors AGO6 and NRPE5a for efficient de novo methylation. A forward genetic approach uncovered alleles of several components of the RdDM pathway, including alleles of clsy1, ktf1 and nrpd/e2, which have not been previously shown to be required for the initial establishment of DNA methylation. Mutations were mapped and genes cloned by both traditional and whole genome sequencing approaches. The methodologies and the mutant alleles discovered will be instrumental in further studies of de novo DNA methylation.Key words: DNA methylation, Arabidopsis, de novo, genetic screen, whole-genome sequencing     

A phosphoramidon-sensitive metalloprotease induces apoptosis of human endothelial cells by Group B Streptococcus

We explored Group B Streptococcus (GBS)-induced apoptosis in human umbilical vein endothelial cells (HUVEC) and the role of phosphoramidon, a zinc metalloprotease inhibitor, in this process. GBS 90186 strain (serotype V, a blood isolate) and concentrated supernatant (CS) were used to investigate the viability and morphological alterations in HUVEC by Trypan blue uptake, electrophoresis in 2 % agarose gel and scanning electron microscopy assays. Apoptosis before and after phosphoramidon-treatment were verified by flow cytometry using annexin V-FITC labeling. Differences were considered significant when P < 0.05 using unpaired Student’s t test. GBS and CS induced HUVEC death by apoptosis (76.5 and 32 %, respectively) with an increasing pro-apoptotic Bax expression and decreasing anti-apoptotic Bcl-2 expression. Caspase-3 was activated during GBS-induced endothelial apoptosis. Phosphoramidon reduced 89.3 and 100 % of GBS and CS cell death by apoptosis, respectively. Some GBS strains may induce cell death by apoptosis with involvement of metalloproteases and signaling through the intrinsic pathway of apoptosis, which may contribute to GBS survival during sepsis of adults and neonates.     

Iron Status and Helicobacter pylori Infection in Symptomatic Children: An International Multi-Centered Study

Objective

Iron deficiency (ID) and iron deficiency anaemia (IDA) are global major public health problems, particularly in developing countries. Whilst an association between H. pylori infection and ID/IDA has been proposed in the literature, currently there is no consensus. We studied the effects of H. pylori infection on ID/IDA in a cohort of children undergoing upper gastrointestinal endoscopy for upper abdominal pain in two developing and one developed country.

Methods

In total 311 children (mean age 10.7±3.2 years) from Latin America - Belo Horizonte/Brazil (n = 125), Santiago/Chile (n = 105) - and London/UK (n = 81), were studied. Gastric and duodenal biopsies were obtained for evaluation of histology and H. pylori status and blood samples for parameters of ID/IDA.

Results

The prevalence of H. pylori infection was 27.7% being significantly higher (p<0.001) in Latin America (35%) than in UK (7%). Multiple linear regression models revealed H. pylori infection as a significant predictor of low ferritin and haemoglobin concentrations in children from Latin-America. A negative correlation was observed between MCV (r = −0.26; p = 0.01) and MCH (r = −0.27; p = 0.01) values and the degree of antral chronic inflammation, and between MCH and the degree of corpus chronic (r = −0.29, p = 0.008) and active (r = −0.27, p = 0.002) inflammation.

Conclusions

This study demonstrates that H. pylori infection in children influences the serum ferritin and haemoglobin concentrations, markers of early depletion of iron stores and anaemia respectively.     

Association Between Uric Acid Levels and Obstructive Sleep Apnea Syndrome in a Large Epidemiological Sample

Introduction

Recurrent hypoxia, which is associated with obstructive sleep apnea syndrome (OSAS), leads to an increase in the degradation of adenosine triphosphatase into xanthine, which in turn increases uric acid concentrations.

Objective

The current study aimed to determine whether an association exists between OSAS and uric acid levels in the peripheral blood from a representative population of Sao Paulo (Brazil).

Methods

A population-based survey adopting a probabilistic 3-stage cluster sample of Sao Paulo was used to represent the population according to gender, age, and socioeconomic class. A total of 1,042 volunteers underwent polysomnography recordings for OSAS diagnosis, blood pressure assessment, and biochemical blood analysis, and answered questionnaires.

Results

Uric acid levels were correlated with most important risk factors for OSAS, such as AHI, desaturation time and index, minimum oxyhemoglobin saturation (SpO₂), blood pressure, cholesterol, BMI, triglycerides and arousal, and with OSAS itself. Also, uric acid was increased in OSAS volunteers even after controlling for all confounders. Hyperuricemic volunteers presented lower mean and minimum SpO₂ and increased desaturation index. Importantly, minimum SpO₂ was a significant predictor of uric acid levels, which in turn was considered an independent predictor for OSAS in the binary logistic model. However, a ROC curve analysis for establishing cut-off points for uric acid levels as a biomarker of OSAS revealed moderate sensitivity and specificity.

Conclusion

A strong association was found between uric acid levels and OSAS in a representative sample of the population of Sao Paulo. Although they do not qualify for a biomarker alone, uric acid levels may be involved in OSAS severity and should be considered in sleep apnea management in the future.     

Subdose of human chorionic gonadotropin applied at the Hou Hai acupoint on follicular dynamics and luteal development in donkeys

The objective of this study was to evaluate the effects of an hCG subdose applied at the Hou Hai acupoint as an ovulation inducer in donkeys. Eleven donkeys were distributed in randomized blocks in T1 = application of 1,500 IU of hCG intravenous (IV); T2 = 450 IU of hCG applied at the false acupoint (IV), and T3 = 450 IU of hCG applied at the Hou Hai acupoint. There was no difference (P > 0.05) between the treatments regarding the mean diameter of the pre-ovulatory follicle (34.5 ± 1.3 mm), the ovulation rate (96.97%), the interval between induction and ovulation (58.07 ± 16.82 h), the mean diameter of the CL (D0 = 23.0 ± 0.6; D2 = 27.7 ± 1.9 and D8 = 28.2 ± 0.8mm), and serum P₄ concentrations (10.50 ± 2.99 ng.mL^-1). The application of 450 IU of hCG at the Hou Hai acupoint increased ovulation rate (72.73%) more than 48 h after induction (P = 0.03) and a larger diameter of the CL on D4 (30.7 ± 5.1 mm) (P = 0.04). The vascularization area of the CL on D8, obtained by minimum number of colored pixel (NCP), was greater (P < 0.05) in the donkeys that received 1,500 IU of IV hCG (T1, 41.91 ± 1.17), and we found a positive correlation (P < 0.05) between mean NCP and P₄ concentration in the donkeys that received 450 IU of hCG IV at the false acupoint (T2) or at the Hou Hai acupoint (T3). The application of 450 IU of hCG by IV route at the false acupoint or the Hou Hai acupoint was sufficient to induce ovulation in donkeys, demonstrating that the average dosage commonly used for this species is too high.     

Hypo- and hyperthyroidism affect NEI concentration in discrete brain areas of adult male rats

To date, there has been only one in vitro study of the relationship between neuropeptide EI (NEI) and the hypothalamic-pituitary-thyroid (HPT) axis. To investigate the possible relationship between NEI and the HPT axis, we developed a rat model of hypothyroidism and hyperthyroidism that allows us to determine whether NEI content is altered in selected brain areas after treatment, as well as whether such alterations are related to the time of day. Hypothyroidism and hyperthyroidism, induced in male rats, with 6-propyl-1-thiouracil and l-thyroxine, respectively, were confirmed by determination of triiodothyronine, total thyroxine, and thyrotropin levels. All groups were studied at the morning and the afternoon. In rats with hypothyroidism, NEI concentration, evaluated on postinduction days 7 and 24, was unchanged or slightly elevated on day 7 but was decreased on day 24. In rats with hyperthyroidism, NEI content, which was evaluated after 4 days of l-thyroxine administration, was slightly elevated, principally in the preoptic area in the morning and in the median eminence-arcuate nucleus and pineal gland in the afternoon, the morning and afternoon NEI contents being similar in the controls. These results provide the bases to pursue the study of the interaction between NEI and the HPT axis.