Bioactive polymeric-ceramic hybrid 3D scaffold for application in bone tissue regeneration

The regeneration of large bone defects remains a challenging scenario from a therapeutic point of view. In fact, the currently available bone substitutes are often limited by poor tissue integration and severe host inflammatory responses, which eventually lead to surgical removal. In an attempt to address these issues, herein we evaluated the importance of alginate incorporation in the production of improved and tunable β-tricalcium phosphate (β-TCP) and hydroxyapatite (HA) three-dimensional (3D) porous scaffolds to be used as temporary templates for bone regeneration. Different bioceramic combinations were tested in order to investigate optimal scaffold architectures. Additionally, 3D β-TCP/HA vacuum-coated with alginate, presented improved compressive strength, fracture toughness and Young's modulus, to values similar to those of native bone. The hybrid 3D polymeric-bioceramic scaffolds also supported osteoblast adhesion, maturation and proliferation, as demonstrated by fluorescence microscopy. To the best of our knowledge this is the first time that a 3D scaffold produced with this combination of biomaterials is described. Altogether, our results emphasize that this hybrid scaffold presents promising characteristics for its future application in bone regeneration.

Multifaces of neuropeptide Y in the brain--neuroprotection, neurogenesis and neuroinflammation

Neuropeptide Y (NPY) has been implicated in the modulation of important features of neuronal physiology, including calcium homeostasis, neurotransmitter release and excitability. Moreover, NPY has been involved as an important modulator of hippocampal and thalamic circuits, receiving particular attention as an endogenous antiepileptic peptide and as a potential master regulator of feeding behavior. NPY not only inhibits excessive glutamate release (decreasing circuitry hyperexcitability) but also protects neurons from excitotoxic cell death. Furthermore, NPY has been involved in the modulation of the dynamics of dentate gyrus and subventricular zone neural stem cell niches. In both regions, NPY is part of the chemical resource of the neurogenic niche and acts through NPY Y1 receptors to promote neuronal differentiation. Interestingly, NPY is also considered a neuroimmune messenger. In this review, we highlight recent evidences concerning paracrine/autocrine actions of NPY involved in neuroprotection, neurogenesis and neuroinflammation. In summary, the three faces of NPY, discussed in the present review, may contribute to better understand the dynamics and cell fate decision in the brain parenchyma and in restricted areas of neurogenic niches, in health and disease.

PP159. In women with previous pregnancy hypertension, cardiovascular risk biomarkers may be modulated by haptoglobin genotype

INTRODUCTION

Preeclampsia may affect the risk for future cardiovascular disease. Haptoglobin (Hp), an acute phase protein with genetic polymorphism (Hp1.1, 2.1 and 2.2) synthesized in the hepatocyte and in many tissues, may modulate the risk through the antioxidant and anti-inflammatory differential effects of their genotypes.

OBJECTIVES

Evaluate some parameters of cardiovascular risk in association with genetic polymorphism of Hp in women with previous preeclampsia (HBP) compared to healthy women during gestation (NBP).

METHODS

We studied 352 women aged 35±5.48 current year, taking these, 165 presented previous preeclampsia, 2-14 (±6.6) years ago. Genetic polymorphism of Hp was determined from plasma by electrophoresis. The different circulating biomarkers, myeloperoxidase ng/mL (MPO) and nitrates and nitrites (nmol/ml) by ELISA, transaminases - AST and ALT (U/L) and apolipoprotein A and B (mg/dL), uric acid (mg/dl) hs-CRP (mg/L) were determined by conventional methods as well as blood pressure (BP) and anthropometric parameters BMI and hip and waist circumference (WC).Statistical methods were Chi-square, ANOVA (Bonferroni) and t-Student.

RESULTS

There were no differences in the distribution of phenotypes of Hp between NBP and those with previous hypertension in pregnancy. There were differences between NBP and HBP in the following parameters: Systolic BP (118.9±13.4 vs 135.0±16.5, p<0.001); Diastolic BP (72.2±10.1 vs 85.9±12.0 p<0.001); MPO (62.3±30.9 vs 85.7±39.4, p=0.020); Nitrite (10.1±3.8 vs 19.1±7.0, p<0.001); ALT (18.0±8.0 vs 22.5±12.9, p=0.016); BMI (25.4±4.1 vs 27.1±4.8, p=0.031); WC (82.8±9.9 vs 89.5±15.6, p=0.002); Apo B (0.6±0.1 vs 0.6±0.1, p=0.023). Those values vary with the genotypes of Hp and were observed Hp 1.1 and 2.1 in NBP and HBP respectively: [Systolic BP 119.2±13.7 vs 134.7±18.3 (p<0.001); Diastolic BP (72.8±11.9 vs 86.2±19.4 p<0.001); MPO (57.9±32.5 vs 94.2±42.1, p=0.008); Nitrites (9.6±3.2 vs 20.0±8.5, p<0.001); ALT(17.0±7.2 vs 20.4±8.0, p=0.033); WC (82.4±10.0 vs 90.8±17.6, p=0.004); Apo A (0.9±0.2 vs 1.0±0.2, p=0.011)] and Hp 2.2 in NBP and HBP respectively: [Systolic BP 118.2±13.1 vs 135.6±12.8 (p<0.001); Diastolic BP (70.9±7.2 vs 85.5±16.3 p<0.001); Nitrites (11.5±5.1 vs 18.0±4.4, p<0.001)].

CONCLUSION

Women with previous hypertension during pregnancy, presented significant differences in some classic cardiovascular risk biomarkers as well as in some others, associated with the inflammatory process, whose variation may be modulated by haptoglobin functional genetic polymorphism. The history of hypertensive disease in pregnancy may be relevant, in association with these biomarkers to the prevention of cardiovascular disease in particular of postmenopausal women.

May exercise prevent addiction?

Amphetamines exert their persistent addictive effects by activating brain's reward pathways, perhaps through the release of dopamine in the nucleus accumbens (and/or in other places). On the other hand, there is a relationship between dopamine and all behavioural aspects that involve motor activity and it has been demonstrated that exercise leads to an increase in the synthesis and release of dopamine, stimulates neuroplasticity and promotes feelings of well-being. Moreover, exercise and drugs of abuse activate overlapping neural systems. Thus, our aim was to study the influence of chronic exercise in the mechanism of addiction using an amphetamine-induced conditioned-place-preference in rats.

Adult male Sprague-Dawley rats were randomly separated in groups with and without chronic exercise. Chronic exercise consisted in a 8 week treadmill running program, with increasing intensity. The conditioned place preference test was performed in both groups using a procedure and apparatus previously established. A 2 mg.kg^-1 amphetamine or saline solution was administered intraperitonially according to the schedule of the conditioned place preference.

Before conditioning none of the animals showed preference for a specific compartment of the apparatus. The used amphetamine dose in the conditioning phase was able to produce a marked preference towards the drug-associated compartment in the group without exercise. In the animals with exercise a significant preference by the compartment associated with saline was observed.

These results lead us to conclude that a previous practice of regular physical activity may help preventing amphetamine addiction in the conditions used in this test.

Candida krusei reservoir in a neutropaenia unit: molecular evidence of a foe?

Candida krusei has been documented as an emerging pathogen causing nosocomial outbreaks. The consecutive isolation of C. krusei strains in three patients admitted to the same hospital department within 2 months lead us to consider the possibility of an outbreak. Additionally, C. krusei isolates were collected from the room surfaces, whereas another isolate had been recovered from the blood of one patient 2 years before. HinfI DNA restriction endonuclease-based analysis of all C. krusei isolates was performed and restriction profiles were compared. Surprisingly, isolates from different patients were unrelated, whereas isolates from biological products of the same patient showed indistinguishable HinfI restriction patterns and were similar to those obtained from the surrounding environment of the respective patients. The study approach revealed the endogenous origin of the C. krusei infectious episodes observed and demonstrated that, subsequent to colonizing a patient, C. krusei can be involved in infectious episodes distant in time. The hypothesis of an outbreak was excluded, although we believe that the methodology employed in the present study represents a valuable tool for diagnostic and epidemiological surveys.

Pupal development of Ceratitis capitata (Diptera: Tephritidae) and Diachasmimorpha longicaudata (Hymenoptera: Braconidae) at different moisture values in four soil types

This study aimed to evaluate adult emergence and duration of the pupal stage of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), and emergence of the fruit fly parasitoid, Diachasmimorpha longicaudata (Ashmead), under different moisture conditions in four soil types, using soil water matric potential. Pupal stage duration in C. capitata was influenced differently for males and females. In females, only soil type affected pupal stage duration, which was longer in a clay soil. In males, pupal stage duration was individually influenced by moisture and soil type, with a reduction in pupal stage duration in a heavy clay soil and in a sandy clay, with longer duration in the clay soil. As matric potential decreased, duration of the pupal stage of C. capitata males increased, regardless of soil type. C. capitata emergence was affected by moisture, regardless of soil type, and was higher in drier soils. The emergence of D. longicaudata adults was individually influenced by soil type and moisture factors, and the number of emerged D. longicaudata adults was three times higher in sandy loam and lower in a heavy clay soil. Always, the number of emerged adults was higher at higher moisture conditions. C. capitata and D. longicaudata pupal development was affected by moisture and soil type, which may facilitate pest sampling and allow release areas for the parasitoid to be defined under field conditions.

Solitary hemangioma of the small bowel disclosed by wireless capsule endoscopy

A nine-year-old child presented with melena and anemia. She had similar symptoms five months earlier and had undergone an extensive workup with upper gastrointestinal endoscopy and colonoscopy, both normal and 99m-Tc-RBC-scintigraphy which was positive in the right lower quadrant. This time, capsule endoscopy was performed and disclosed an hemangioma with a dark spot suggesting recent bleeding in the ileum. The lesion was resected. Pathological examination revealed a transmural cavernous hemangioma. Small bowel hemangioma is a rare disease. Its diagnosis is extremely difficult and is usually obtained during surgery. Capsule endoscopy is an endoscopic technique that can improve preoperative diagnosis, as reported in the present case.

Autonomy and susceptibility to HIV/AIDS among young women living in a slum in Belo Horizonte, Brazil

In Brazil in the last decade there has been an increase in the susceptibility of young women to HIV. This study explored the link between autonomy, or control over major domains of economic, social and sexual life, and susceptibility to HIV infection among poor young women living in an urban slum area of Brazil. A cross-sectional survey was carried out on a random sample of 356 young women between 15 and 24 years old. The study found that indicators of autonomy that relate to sexuality, mobility and freedom from threat by partners were significantly correlated with practices linked to HIV prevention and with access to health services promoting prevention, especially among adolescents. Young women who talked to their partner about condom use before first intercourse and co-decided with them on condom use were more likely to use condoms. In contrast, those who had ever been victim of physical violence by a partner or whose partners restricted their mobility were less likely to use condoms. The study found that young women were more likely to have accessed health services for gynaecological examinations, family planning services and HIV testing if they had ever been pregnant. The findings indicate that structural gender inequalities translate into unequal relationships and reduced autonomy, increasing young women's susceptibility to HIV. A bias in HIV testing and reproductive health services towards pregnant women leaves many susceptible youth without early access. The study suggests the development of a reproductive health policy that ensures that young women access services before they get pregnant and that also reaches young males.

Neuropeptide Y can rescue neurons from cell death following the application of an excitotoxic insult with kainate in rat organotypic hippocampal slice cultures

In the present work we investigated the neuroprotective role of neuropeptide Y (NPY) after an excitotoxic insult in rat organotypic hippocampal slice cultures. Exposure of 2 week-old rat hippocampal slice cultures to 12muM kainate (KA) for 24h induced neuronal death in dentate gyrus (DG) granular cell layer, CA1 and CA3 pyramidal cell layers, as quantified by cellular propidium iodide (PI) uptake. The activation of Y(1) or Y(2) receptors 30min after starting the exposure to the excitotoxic insult with kainate resulted in neuroprotection by reducing the PI uptake in DG, CA1 and CA3 cell layers. The use of Y(1) or Y(2) receptors antagonists, BIBP3226 (1muM) or BIIE0246 (1muM), resulted in the loss of the neuroprotection induced by the activation of Y(1) or Y(2) receptors, respectively, in all hippocampal subfields. Taken together these results suggest that activation of NPY Y(1) or Y(2) receptors activates neuroprotective pathways that are able to rescue neurons from excitotoxic cell death.