The striatum drives the ergogenic effects of caffeine

Caffeine is one of the main ergogenic resources used in exercise and sports. Previously, we reported the ergogenic mechanism of caffeine through neuronal A2AR antagonism in the central nervous system [1]. We now demonstrate that the striatum rules the ergogenic effects of caffeine through neuroplasticity changes. Thirty-four Swiss (8-10 weeks, 47 ± 1.5 g) and twenty-four C57BL/6J (8-10 weeks, 23.9 ± 0.4 g) adult male mice were studied behaviorly and electrophysiologically using caffeine and energy metabolism was studied in SH-SY5Y cells. Systemic (15 mg/kg, i.p.) or striatal (bilateral, 15 μg) caffeine was psychostimulant in the open field (p < 0.05) and increased grip efficiency (p < 0.05). Caffeine also shifted long-term depression (LTD) to potentiation (LTP) in striatal slices and increased the mitochondrial mass (p < 0.05) and membrane potential (p < 0.05) in SH-SY5Y dopaminergic cells. Our results demonstrate the role of the striatum in the ergogenic effects of caffeine, with changes in neuroplasticity and mitochondrial metabolism.

Sonic Activation of a Desensitizing Gel Prior to In-Office Bleaching

This double-blind, randomized, and controlled clinical trial evaluated the effect of sonic activation during the application of a desensitizing agent (DA) containing 5% potassium nitrate and 2% sodium fluoride on the occurrence of tooth sensitivity (TS) associated with in-office dental bleaching. Treatment with or without sonic activation of the DA was randomly assigned to one-half of the maxillary teeth of 34 patients in a split-mouth design. On the side without sonic activation (noSA), the DA was applied and maintained in contact with the teeth for 10 minutes. On the sonic activation side (SA), the DA was activated 30 seconds per tooth. The DA application was followed by application of 35% hydrogen peroxide in two bleaching sessions separated by a one-week interval. The primary outcome was the absolute risk of TS, recorded using a numeric rating scale and a visual analog scale. Color was evaluated with a digital spectrophotometer and a value-oriented shade guide. No significant difference between treatments was observed in the absolute risk of TS, which occurred in 93% (p=1.00) of both noSA and SA groups. The TS intensity was higher in the 24-hour interval after sessions, for both treatments, without differences between them. There was no difference in the color change for the treatments, with the average change in number of shade guide units of the Vita Classical scale of 6.35 for both (p=0.87). Sonic activation of DA containing 5% potassium nitrate and 2% sodium fluoride did not reduce the absolute risk and intensity of TS associated with in-office bleaching.

Comparison of the Effect of Agitation on Whitening and Tooth Sensitivity of In-Office Bleaching: A Randomized Clinical Trial

OBJECTIVE

This single-blind, split-mouth, randomized trial was aimed at evaluating the bleaching efficacy (BE) and tooth sensitivity (TS) of a 20% hydrogen peroxide (HP) bleaching agent used under active or passive application.

METHODS AND MATERIALS

Twenty-two patients with canines darker than C2 were selected. Teeth were bleached in two sessions, with a one-week interval between treatments. The bleaching agent was applied using active (HPactive) or passive (HPpassive) application. Each tooth in the HPactive-allocated hemiarch received bleaching gel with sonic activation after 10 and 30 minutes from the start of treatment, with rounded movements all over the buccal surface. The color changes were evaluated by subjective (Vita Classical and Vita Bleachedguide) and objective (VITA Easyshade Spectrophotometer) methods at baseline and 30 days after the second session. TS was recorded up to 48 hours after treatment using a 0-10 visual analog scale. Color change in shade guide units (SGUs) and ΔE was analyzed using a Wilcoxon test (α=0.05). The absolute risk and intensity of TS were evaluated using McNemar test and a Wilcoxon test, respectively (α=0.05).

RESULTS

Significant whitening was observed in both groups after 30 days of clinical evaluation. The activation did not significantly influence BE (ΔSGU HPpassive=5.6 and HPActive=5.8; p=0.98; and ΔE HPpassive=10.6 and HPactive=10.3; p=0.83). Absolute risk of TS (HPactive=36.4% and HPpassive=31.8%; p=0.94) was similar for both groups (Fisher exact test). TS intensity (visual analogue scale) was higher during the bleaching sessions and up to 24 hours thereafter for both groups, with no differences between groups (twoway analysis of variance and Tukey).

CONCLUSION

The active application of a 20% HP gel did not improve BE and TS.

Aspergillus section Flavi and aflatoxins in Brazilian cassava (Manihot esculenta Crantz) and products

Aflatoxins are carcinogenic compounds produced by some species of Aspergillus, especially those belonging to Aspergillus section Flavi. Their occurrence in food may start in the field, in the post-harvest, or during storage due to inadequate handling and storage. Because cassava is a staple food for a high percentage of the Brazilian population, we evaluated the presence of aflatoxin-producing species in cassava tubers, cassava products (cassava flour, cassava starch, sour starch, and tapioca flour), and in soil samples collected from cassava fields. In addition, the levels of aflatoxin contamination in cassava products were quantified. A total of 101 samples were analyzed, and 45 strains of Aspergillus section Flavi were isolated. Among the identified species, Aspergillus flavus, Aspergillus arachidicola, Aspergillus novoparasiticus, and Aspergillus parasiticus were found. The majority of strains (73.3%) tested for their aflatoxin-producing ability in synthetic media was positive. Despite that, cassava and cassava products were essentially free of aflatoxins, and only one sample of cassava flour contained traces of AFB₁ (0.35 μg/kg).

Clinical Effects of Desensitizing Prefilled Disposable Trays in In-office Bleaching: A Randomized Single-blind Clinical Trial

Objectives:

This study aimed to evaluate the desensitizing effect of a prefilled disposable tray containing potassium nitrate and fluoride on the self-reported tooth sensitivity (TS) and the bleaching efficacy of 40% hydrogen peroxide bleaching agent used for in-office bleaching in comparison with potassium nitrate and fluoride gel applied in a conventional-delivered tray system in an equivalence clinical trial.

Methods and Materials:

Seventy-eight patients, with a right maxillary canine darker than A3, were selected for this single-blind (evaluators), randomized clinical trial. Teeth were bleached in two sessions with a one-week interval in between. Before in-office bleaching, the prefilled disposable tray or conventional tray containing potassium nitrate and fluoride was used for 15 minutes. Subsequently, the bleaching agent was applied in two 20-minute applications (per the manufacturer's directions) in each session. The color change was evaluated by subjective (Vita Classical and Vita Bleachedguide) and objective (Easyshade Advance Spectrophotometer) methods at baseline and 30 days after the first bleaching session. TS was recorded for up to 48 hours using a 0-10 visual analog scale. The absolute risk was evaluated by chi-square test, while the intensity of TS was evaluated by McNemar test (α=0.05). Color change in shade guide units and ΔE was analyzed by Student t-test for independent samples (α=0.05).

Results:

Significant whitening was observed in both groups after 30 days of clinical evaluation. The use of different methods of desensitizer in a tray did not influence the absolute risk and intensity of TS (p&gt;0.05), although a tendency of lower risk of TS with the prefilled disposable tray containing potassium nitrate and fluoride was observed.

Conclusion:

The use of a prefilled disposable tray containing potassium nitrate and fluoride before the application of the in-office bleaching product did not affect the whitening degree and decreased self-reported TS when compared with a conventional-delivered tray system.

Effectiveness of In-office Hydrogen Peroxide With Two Different Protocols: A Two-center Randomized Clinical Trial

Objectives:

The aim of this study was to compare the bleaching efficacy and tooth sensitivity (TS) of a 38% hydrogen peroxide bleaching agent used for in-office bleaching, applied under different time protocols: a 40-minute application or two 20-minute applications.

Methods and Materials:

Forty-four patients from Brazil and Colombia, with right superior canines darker than C2, were selected for this multicenter, single-blind, randomized trial. The teeth were bleached in two sessions, with a one-week interval between them, in a split-mouth design. The bleaching agent was applied in two 20-minute (2×20) applications or one 40-minute (1×40) application in each session according to the manufacturer's instructions. The color changes were evaluated by using subjective (Vita Classical and Vita Bleachedguide) and objective (Easyshade Spectrophotometer) methods at baseline and 30 days after the second session. Tooth sensitivity was recorded up to 48 hours with a 0-10 visual analog scale. Also, the pH values during the application of bleaching were recorded. Color change in shade guide units and ΔE were analyzed by using the Student t-test (α=0.05). The absolute risk and intensity of TS were evaluated with the McNemar test, the Wilcoxon signed-rank test, and the Friedman test, respectively (α= 0.05).

Results:

Significant whitening was observed in both groups after 30 days of clinical evaluation. The use of a 40-minute application did not significantly influence the absolute risk of TS (68%, 95% confidence interval [CI] = 53-80) as well as the intensity of TS compared with the acid bleaching gel (absolute risk of 82%, 95% CI = 68-91). The pH values did not differ significantly between groups and at the different assessment periods (p=0.42).

Conclusion:

The use of a 40-minute in-office bleaching agent gel application produced the same whitening degree and TS that the two 20-minute bleaching agent applications did. The former preferably should be applied because one 40-minute application does not require gel refreshing.

Mitofusin-mediated ER stress triggers neurodegeneration in pink1/parkin models of Parkinson's disease

Mutations in PINK1 and PARKIN cause early-onset Parkinson's disease (PD), thought to be due to mitochondrial toxicity. Here, we show that in Drosophila pink1 and parkin mutants, defective mitochondria also give rise to endoplasmic reticulum (ER) stress signalling, specifically to the activation of the protein kinase R-like endoplasmic reticulum kinase (PERK) branch of the unfolded protein response (UPR). We show that enhanced ER stress signalling in pink1 and parkin mutants is mediated by mitofusin bridges, which occur between defective mitochondria and the ER. Reducing mitofusin contacts with the ER is neuroprotective, through suppression of PERK signalling, while mitochondrial dysfunction remains unchanged. Further, both genetic inhibition of dPerk-dependent ER stress signalling and pharmacological inhibition using the PERK inhibitor GSK2606414 were neuroprotective in both pink1 and parkin mutants. We conclude that activation of ER stress by defective mitochondria is neurotoxic in pink1 and parkin flies and that the reduction of this signalling is neuroprotective, independently of defective mitochondria. A video abstract for this article is available online in the supplementary information

Parp mutations protect against mitochondrial dysfunction and neurodegeneration in a PARKIN model of Parkinson's disease

The co-enzyme nicotinamide adenine dinucleotide (NAD⁺) is an essential co-factor for cellular energy generation in mitochondria as well as for DNA repair mechanisms in the cell nucleus involving NAD⁺-consuming poly (ADP-ribose) polymerases (PARPs). Mitochondrial function is compromised in animal models of Parkinson's disease (PD) associated with PARKIN mutations. Here, we uncovered alterations in NAD⁺ salvage metabolism in Drosophila parkin mutants. We show that a dietary supplementation with the NAD⁺ precursor nicotinamide rescues mitochondrial function and is neuroprotective. Further, by mutating Parp in parkin mutants, we show that this increases levels of NAD⁺ and its salvage metabolites. This also rescues mitochondrial function and suppresses dopaminergic neurodegeneration. We conclude that strategies to enhance NAD⁺ levels by administration of dietary precursors or the inhibition of NAD⁺-dependent enzymes, such as PARP, that compete with mitochondria for NAD⁺ could be used to delay neuronal death associated with mitochondrial dysfunction.

Unravelling mitochondrial pathways to Parkinson's disease

Mitochondria are essential for cellular function due to their role in ATP production, calcium homeostasis and apoptotic signalling. Neurons are heavily reliant on mitochondrial integrity for their complex signalling, plasticity and excitability properties, and to ensure cell survival over decades. The maintenance of a pool of healthy mitochondria that can meet the bioenergetic demands of a neuron, is therefore of critical importance; this is achieved by maintaining a careful balance between mitochondrial biogenesis, mitochondrial trafficking, mitochondrial dynamics and mitophagy. The molecular mechanisms that underlie these processes are gradually being elucidated. It is widely recognized that mitochondrial dysfunction occurs in many neurodegenerative diseases, including Parkinson's disease. Mitochondrial dysfunction in the form of reduced bioenergetic capacity, increased oxidative stress and reduced resistance to stress, is observed in several Parkinson's disease models. However, identification of the recessive genes implicated in Parkinson's disease has revealed a common pathway involving mitochondrial dynamics, transport, turnover and mitophagy. This body of work has led to the hypothesis that the homeostatic mechanisms that ensure a healthy mitochondrial pool are key to neuronal function and integrity. In this paradigm, impaired mitochondrial dynamics and clearance result in the accumulation of damaged and dysfunctional mitochondria, which may directly induce neuronal dysfunction and death. In this review, we consider the mechanisms by which mitochondrial dysfunction may lead to neurodegeneration. In particular, we focus on the mechanisms that underlie mitochondrial homeostasis, and discuss their importance in neuronal integrity and neurodegeneration in Parkinson's disease.

Drosophila ref(2)P is required for the parkin-mediated suppression of mitochondrial dysfunction in pink1 mutants

Autophagy is a critical regulator of organellar homeostasis, particularly of mitochondria. Upon the loss of membrane potential, dysfunctional mitochondria are selectively removed by autophagy through recruitment of the E3 ligase Parkin by the PTEN-induced kinase 1 (PINK1) and subsequent ubiquitination of mitochondrial membrane proteins. Mammalian sequestrome-1 (p62/SQSTM1) is an autophagy adaptor, which has been proposed to shuttle ubiquitinated cargo for autophagic degradation downstream of Parkin. Here, we show that loss of ref(2)P, the Drosophila orthologue of mammalian P62, results in abnormalities, including mitochondrial defects and an accumulation of mitochondrial DNA with heteroplasmic mutations, correlated with locomotor defects. Furthermore, we show that expression of Ref(2)P is able to ameliorate the defects caused by loss of Pink1 and that this depends on the presence of functional Parkin. Finally, we show that both the PB1 and UBA domains of Ref(2)P are crucial for mitochondrial clustering. We conclude that Ref(2)P is a crucial downstream effector of a pathway involving Pink1 and Parkin and is responsible for the maintenance of a viable pool of cellular mitochondria by promoting their aggregation and autophagic clearance.

Effect of 2% chlorhexidine digluconate on bond strength of a glass-fibre post to root dentine

AIM

To assess the immediate influence of dentine bonding systems (DBS) associated with 2% chlorhexidine digluconate (CHX) on glass-fibre post-bond strength to root dentine, in terms of coronal, middle and apical thirds.

METHODOLOGY

Sixty bovine roots were root filled and randomly assigned to 1 of 6 groups (n = 10): SBMP (3-step etch-and-rinse system, Scotchbond Multi-Purpose), SB (2-step etch-and-rinse system, Single Bond 2), SE (2-step self-etching system, Clearfil SE Bond) and SBMP-CHX, SB-CHX and SE-CHX, respectively, associated with CHX. For all groups, a glass-fibre post was luted with a dual-cure resin cement, RelyX ARC. After 7-day storage, specimens were subjected to the push-out test. Failure modes were analysed under optical microscopy (40x). Bond strength values were statistically analysed by two-way anova and Bonferroni tests (P < 0.05).

RESULTS

The effect of DBS was significant (P < 0.05), and SE reached higher bond strength in comparison with the other DBS tested. CHX association did not show improvement with any DBS (P > 0.05); rather, it negatively affected SE, which was detected for all thirds. There was no difference between thirds (P > 0.05), except for the SE-CHX, which presented lower values for the apical third (P < 0.05). Adhesive cement/dentine adhesive failure was predominant for all groups. CHX did not influence the failure mode for any DBS (P > 0.05).

CONCLUSIONS

The performance of the dentine bonding systems was material dependent. CHX did not improve immediate bond strength; however, CHX negatively affected the bond strength of the self-etching system, especially in the third apical.

Evaluation of Chemical Treatment on Zirconia Surface with Two Primer Agents and an Alkaline Solution on Bond Strength

Objectives

This study evaluated the effect of an alkaline solution and two 10-methacryloyloxydecyl dihydrogen phosphate (MDP)-based primer agents on bond strength to zirconia (yttria-stabilized tetragonal zirconium polycrystal [Y-TZP]) through the shear bond strength (SBS) test.

Materials and Methods

Sixty square-shaped Y-TZP samples were embedded in an acrylic resin mold, polished, and randomly assigned to one of six groups (n=10) according to treatment surface: group CR, no treatment (control); group NaOH, 0.5 M NaOH; group AP, Alloy Primer; group ZP, Z-Primer Plus; group NaOH-AP, 0.5 M NaOH + Alloy Primer; and group NaOH-ZP, 0.5 M NaOH + Z-Primer Plus. The resin cement (Rely X U100) was applied inside a matrix directly onto the Y-TZP surface, and it was light-cured for 40 seconds. The samples were stored in distilled water at 37°C for 24 hours prior to the test, which was performed in a universal machine at a crosshead-speed of 0.5 mm/min. The data were analyzed by one-way analysis of variance and Tukey tests (p&lt;0.05). Light stereomicroscopy and scanning electron microscopy were used to assess the surface topography and failure mode.

Results

The SBS was significantly affected by the chemical treatment (p&lt;0.0001). The AP group displayed the best results, and the use of NaOH did not improve SBS results relative to either AP or ZP. The samples treated with Alloy Primer displayed mainly mixed failures, whereas those conditioned with Z-Primer Plus or with 0.5 M NaOH presented a balanced distribution of adhesive and mixed failure modes.

Conclusions

The use of a NaOH solution may have modified the reactivity of the Y-TZP surface, whereas the employment of a MDP/6-4-vinylbenzyl-n-propyl amino-1,3,5-triazine-2,4-dithione–based primer enhanced the Y-TZP bond strength.

Genetic analysis of mitochondrial protein misfolding in Drosophila melanogaster

Protein misfolding has a key role in several neurological disorders including Parkinson's disease. Although a clear mechanism for such proteinopathic diseases is well established when aggregated proteins accumulate in the cytosol, cell nucleus, endoplasmic reticulum and extracellular space, little is known about the role of protein aggregation in the mitochondria. Here we show that mutations in both human and fly PINK1 result in higher levels of misfolded components of respiratory complexes and increase in markers of the mitochondrial unfolded protein response. Through the development of a genetic model of mitochondrial protein misfolding employing Drosophila melanogaster, we show that the in vivo accumulation of an unfolded protein in mitochondria results in the activation of AMP-activated protein kinase-dependent autophagy and phenocopies of pink1 and parkin mutants. Parkin expression acts to clear mitochondria with enhanced levels of misfolded proteins by promoting their autophagic degradation in vivo, and refractory to Sigma P (ref(2)P), the Drosophila orthologue of mammalian p62, is a critical downstream effector of this quality control pathway. We show that in flies, a pathway involving pink1, parkin and ref(2)P has a role in the maintenance of a viable pool of cellular mitochondria by promoting organellar quality control.

Reliability of reduced-thickness and thinly veneered lithium disilicate crowns

The present investigation hypothesized that the reliability of reduced-thickness monolithic lithium disilicate crowns is high relative to that of veneered zirconia (Y-TZP) and comparable with that of metal ceramic (MCR) systems. CAD/CAM first mandibular molar full-crown preparations were produced with uniform thicknesses of either 1.0-mm or 2.0-mm occlusal and axial reduction, then replicated in composite for standard crown dies. Monolithic 1.0-mm (MON) and 2.0-mm CAD/CAM lithium disilicate crowns, the latter with a buccal thin veneer (BTV) of 0.5 mm, were fabricated and then sliding-contact-fatigued (step-stress method) until failure or suspension (n = 18/group). Crack evolution was followed, and fractography of post mortem specimens was performed and compared with that of clinical specimens. Use level probability Weibull calculation (use load = 1,200 N) showed interval overlaps between MON and BTV. There was no significant difference between the Weibull characteristic failure loads of MON and BTV (1,535 N [90% CI 1,354-1,740] and 1,609 N [90% CI 1,512-1,712], respectively), which were significantly higher than that of Y-TZP (370 N [90% CI 322-427]) and comparable with that of MCR (1,304 N [90% CI 1,203-1,414]), validating the study hypothesis.

GD1a modulates GM-CSF-induced cell proliferation

Gangliosides have been extensively described to be involved in the proliferation and differentiation of various cell types, such including hematopoietic cells. Our previous studies on murine models of stroma-mediated myelopoiesis have shown that gangliosides are required for optimal capacity of stromal cells to support proliferation of myeloid precursor cells, being shed to the supernatant and selectively incorporated into myeloid cell membranes. Here we describe the effect of gangliosides on the specific granulocyte-macrophage colony-stimulating factor (GM-CSF)-induced proliferation. For that, we used the monocytic FDC-P1 cell line, which is dependent upon GM-CSF for survival and proliferation. Cells were cultured in the presence of GM-CSF and exogenous gangliosides (GM3, GD1a or GM1) or in the absence of endogenous ganglioside synthesis by the use of a ceramide-synthase inhibitor, D-PDMP. We observed that exogenous addition of GD1a enhanced the GM-CSF-induced proliferation of the FDC-P1 cells. Also, we detected an increase in the expression of the α isoform of the GM-CSF receptor (GMRα) as well as of the transcription factor C/EBPα. On the contrary, inhibition of glucosylceramide synthesis was accompanied by a decrease in cell proliferation, which was restored upon the addition of exogenous GD1a. We also show a co-localization of GD1a and GMR by immunocytochemistry. Taken together, our results suggest for the first time that ganglioside GD1a play a role on the modulation of GM-CSF-mediated proliferative response, which might be of great interest not only in hematopoiesis, but also in other immunological processes, Alzheimer disease, alveolar proteinosis and wherever GM-CSF exerts its effects.

Phosphorylation of HtrA2 by cyclin-dependent kinase-5 is important for mitochondrial function

The role of the serine protease HtrA2 in neuroprotection was initially identified by the demonstration of neurodegeneration in mice lacking HtrA2 expression or function, and the interesting finding that mutations adjacent to two putative phosphorylation sites (S142 and S400) have been found in Parkinson's disease patients. However, the mechanism of this neuroprotection and the signalling pathways associated with it remain mostly unknown. Here we report that cyclin-dependent kinase-5 (Cdk5), a kinase implicated in the pathogenesis of several neurodegenerative diseases, is responsible for phosphorylating HtrA2 at S400. HtrA2 and Cdk5 interact in human and mouse cell lines and brain, and Cdk5 phosphorylates S400 on HtrA2 in a p38-dependent manner. Phosphorylation of HtrA2 at S400 is involved in maintaining mitochondrial membrane potential under stress conditions and is important for mitochondrial function, conferring cells protection against cellular stress.

Mitochondrial dysfunction triggered by loss of HtrA2 results in the activation of a brain-specific transcriptional stress response

Cellular stress responses can be activated following functional defects in organelles such as mitochondria and the endoplasmic reticulum. Mitochondrial dysfunction caused by loss of the serine protease HtrA2 leads to a progressive movement disorder in mice and has been linked to parkinsonian neurodegeneration in humans. Here, we demonstrate that loss of HtrA2 results in transcriptional upregulation of nuclear genes characteristic of the integrated stress response, including the transcription factor CHOP, selectively in the brain. We also show that loss of HtrA2 results in the accumulation of unfolded proteins in the mitochondria, defective mitochondrial respiration and enhanced production of reactive oxygen species that contribute to the induction of CHOP expression and to neuronal cell death. CHOP expression is also significantly increased in Parkinson's disease patients' brain tissue. We therefore propose that this brain-specific transcriptional response to stress may be important in the advance of neurodegenerative diseases.

Chemosensitization effects of XIAP downregulation in K562 leukemia cells

The effect of downregulation of the expression of the antiapoptotic protein XIAP with antisense oligonucleotides was evaluated in the K562 chronic myeloid leukemia (CML) cell line. This was carried out by studying the effects of downregulation of XIAP expression on cellular viability, cellular apoptosis and on the response to two chemotherapeutical drugs, etoposide and doxorubicin. We document that downregulation of XIAP expression decreased cellular viability, increased cellular apoptosis and enhanced the effects of doxorubicin.

[Control of the postoperative pain]

The pain is a frequent symptom during the postoperative period and results in suffering and unnecessary risks for the patient. Studies show the inadequate pain relief after surgery and the relationship with erroneous assessment and non-acquaintance about analgesics methods. The article discuss the postoperative pain management which includes the use of nonsteroidal antiinflammatory drugs, opioids, cognitive-behavior interventions and high-tech like epidural catheter and patient-controlled analgesia systems. Besides the adequate pain control includes the discussion about ethical and economic aspects.

Coccidioides immitis isolated from armadillos (Dasypus novemcinctus) in the state of Piauí, northeast Brazil

Natural infection of armadillos with Coccidioides immitis was studied in the state of Piauí, northeast of Brazil, endemic for coccidioidomycosis. In 1998, 26 nine-banded armadillos (Dasypus novemcinctus) were captured in 4 different counties. The animals were sacrificed under deep anesthesia with ether. At necropsy fragments of spleen, liver, lungs and heart were homogenized and seeded onto Sabouraud dextrose agar with and without cycloheximide (BBL, USA). Part of each organ was also processed for histological examination. Suspected colonies of filamentous fungi observed after the second week of incubation at room temperature, exhibiting barrel-shaped arthroconidia alternating with empty spaces, were inoculated intraperitoneally into mice. Three armadillos proved to be infected with C. immitis. Mice inoculated with suspected colonies obtained from homogenized spleen of three and liver of two armadillos developed disseminated coccidioidomycosis and immature and mature spherules of C. immitis were disclosed in several organs. For the first time armadillos (D. novemcinctus) were found naturally infected with C. immitis, adding new data on the ecology and on a possible role of these ancestral mammals in the evolutionary life cycle of this fungus.

The ubiquitin-proteasome pathway regulates survivin degradation in a cell cycle-dependent manner

Survivin, a human inhibitor of apoptosis protein (IAP), plays an important role in both cell cycle regulation and inhibition of apoptosis. Survivin is expressed in cells during the G(2)/M phase of the cell cycle, followed by rapid decline of both mRNA and protein levels at the G(1) phase. It has been suggested that cell cycle-dependent expression of survivin is regulated at the transcriptional level. In this study we demonstrate involvement of the ubiquitin-proteasome pathway in post-translational regulation of survivin. Survivin is a short-lived protein with a half-life of about 30 minutes and proteasome inhibitors greatly stabilise survivin in vivo. Expression of the survivin gene under the control of the CMV promoter cannot block cell cycle-dependent degradation of the protein. Proteasome inhibitors can block survivin degradation during the G(1) phase and polyubiquitinated derivatives can be detected in vivo. Mutation of critical amino acid residues within the baculovirus IAP repeat (BIR) domain or truncation of the N terminus or the C terminus sensitises survivin to proteasome degradation. Together, these results indicate that the ubiquitin-proteasome pathway regulates survivin degradation in a cell cycle-dependent manner and structural changes greatly destabilise the survivin protein.

Mammalian caspases: structure, activation, substrates, and functions during apoptosis

Apoptosis is a genetically programmed, morphologically distinct form of cell death that can be triggered by a variety of physiological and pathological stimuli. Studies performed over the past 10 years have demonstrated that proteases play critical roles in initiation and execution of this process. The caspases, a family of cysteine-dependent aspartate-directed proteases, are prominent among the death proteases. Caspases are synthesized as relatively inactive zymogens that become activated by scaffold-mediated transactivation or by cleavage via upstream proteases in an intracellular cascade. Regulation of caspase activation and activity occurs at several different levels: (a) Zymogen gene transcription is regulated; (b) antiapoptotic members of the Bcl-2 family and other cellular polypeptides block proximity-induced activation of certain procaspases; and (c) certain cellular inhibitor of apoptosis proteins (cIAPs) can bind to and inhibit active caspases. Once activated, caspases cleave a variety of intracellular polypeptides, including major structural elements of the cytoplasm and nucleus, components of the DNA repair machinery, and a number of protein kinases. Collectively, these scissions disrupt survival pathways and disassemble important architectural components of the cell, contributing to the stereotypic morphological and biochemical changes that characterize apoptotic cell death.

[Suggestions for stress relieve at the workplace: opinion of postgraduate nurses]

The work overload, relationship and communication problems, institution's characteristics and ambiental pollution were the stressing organization agents with the greatest punctuation in this study composed by 30 nurses. The work planning, work humanization, suitable human resources, improving communication and continued education were the suggestions given by nurses to minimize these stressing organizational agents. Analysing the stressing extra organizational agents, economic and familiar problems, work distance and transportation to work, were the most pointed.

Survival and proliferation of cells expressing caspase-uncleavable Poly(ADP-ribose) polymerase in response to death-inducing DNA damage by an alkylating agent

To determine whether caspase-3-induced cleavage of poly(ADP-ribose) polymerase (PARP), a DNA damage-sensitive enzyme, alters the balance between survival and death of the cells following DNA damage, we created stable cell lines that express either caspase-uncleavable mutant or wild type PARP in the background of PARP (-/-) fibroblasts. The survival and apoptotic responses of these cells were compared after exposure to N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), a DNA-damaging agent that activates PARP, or to tumor necrosis factor-alpha, which causes apoptosis without initial DNA damage. In response to MNNG, the cells with caspase-uncleavable PARP were very resistant to loss of viability or induction of apoptosis. Most significantly, approximately 25% of these cells survived and retained clonogenicity at a level of DNA damage that eliminated the cells with wild type PARP or PARP (-/-) cells. Expression of caspase-uncleavable PARP could not protect the cells from death induced by tumor necrosis factor, although there was a slower progression of apoptotic events in these cells. Therefore, one of the functions for cleavage of PARP during apoptosis induced by alkylating agents is to prevent survival of the extensively damaged cells.

[Nursing care of patients with bipolar disorder and feelings of the student nurse: study of a case]

This paper is report of an experience, while graduation student during the Psychiatric Nursing Discipline, where I accompanied a patient carrier of Bipolar Disorder of fasting changing. The nurse-patient interaction is very important because it is through a good relationship that we a trust entail, capable to help the patient in the two different phases, with plans of individualized cares. I comment the depressives and maniacs behaviors of the patient in this study and the therapeutic techniques used in each phase. My feelings during the interaction were analyzed front to the behaviors presented by the patient.

Involvement of FADD and caspase-8 signalling in detachment-induced apoptosis

Detachment of most untransformed adherent cells from the extracellular matrix promotes apoptosis, in a process termed anoikis [1] [2]. The death signalling mechanisms involved in this process are not known, although adhesion or transformation by ras oncogenes have been shown to protect epithelial cells from apoptosis through activation of phosphatidylinositol 3-kinase and protein kinase B (PKB/Akt) [3]. Here we show that detachment-induced apoptosis (anoikis) is blocked by the expression of a dominant-negative form of FAS-associated death domain protein (FADD) in a number of untransformed epithelial cell lines. Because the soluble extracellular domains of the death receptors CD95, DR4 and DR5 failed to block anoikis, we conclude that ligand-dependent activation of these death receptors is not involved in this process. Detachment induced strong activation of caspase 8 and caspase 3. Detachment-induced caspase-8 activation did not require the function of downstream caspases but was blocked by overexpression of the anti-apoptotic proteins Bcl-2 or Bcl-X(L). We propose that caspase-8 activation is the initiating event in anoikis, which is subsequently subject to a positive-feedback loop involving mitochondrial events.

Characterization of caspase processing and activation in HL-60 cell cytosol under cell-free conditions. Nucleotide requirement and inhibitor profile

The present studies compared caspase activation under cell-free conditions in vitro and in etoposide-treated HL-60 leukemia cells in situ. Immunoblotting revealed that incubation of HL-60 cytosol at 30 degrees C in the presence of cytochrome c and ATP (or dATP) resulted in activation of procaspases-3, -6, and -7 but not -2 and -8. Although similar selectivity was observed in intact cells, affinity labeling revealed that the active caspase species generated in vitro and in situ differed in charge and abundance. ATP and dATP levels in intact HL-60 cells were higher than required for caspase activation in vitro and did not change before caspase activation in situ. Replacement of ATP with the poorly hydrolyzable analogs 5'-adenylyl methylenediphosphate, 5'-adenylyl imidodiphosphate, or 5'-adenylyl-O-(3-thiotriphos-phate) slowed caspase activation in vitro, suggesting that ATP hydrolysis is required. Caspase activation in vitro was insensitive to phosphatase and kinase inhibitors (okadaic acid, staurosporine, and genistein) but was inhibited by Zn(2+), aurintricarboxylic acid, and various protease inhibitors, including 3,4-dichloroisocoumarin, N(alpha)-p-tosyl-L-phenylalanine chloromethyl ketone, N(alpha)-p-tosyl-L-lysine chloromethyl ketone, and N-(N(alpha)-benzyloxycarbonylphenylalanyl)alanine fluoromethyl ketone, each of which inhibited recombinant caspases-3, -6, -7, and -9. Experiments with anti-neoepitope antiserum confirmed that these agents inhibited caspase-9 activation. Collectively, these results suggest that caspase-9 activation requires nucleotide hydrolysis and is inhibited by agents previously thought to affect apoptosis by other means.

Comparison of paclitaxel-, 5-fluoro-2'-deoxyuridine-, and epidermal growth factor (EGF)-induced apoptosis. Evidence for EGF-induced anoikis

Epidermal growth factor (EGF), a hormone that stimulates proliferation of many cell types, induces apoptosis in some cell lines that overexpress the EGF receptor. To evaluate the mechanism of EGF-induced apoptosis, MDA-MB-468 breast cancer cells were examined by microscopy, flow cytometry, immunoblotting, enzyme assays, and affinity labeling after treatment with EGF, paclitaxel, or 5-fluoro-2'-deoxyuridine (5FUdR). Apoptosis induced by all three agents was accompanied by activation of caspases-3, -6, and -7, as indicated by disappearance of the corresponding zymogens from immunoblots, cleavage of substrate polypeptides in situ, and detection of active forms of these caspases in cytosol and nuclei using fluorogenic assays and affinity labeling. Further analysis indicated involvement of the cytochrome c/Apaf-1/caspase-9 pathway of caspase activation, but not the Fas/Fas ligand pathway. Interestingly, caspase activation was consistently lower after EGF treatment than after paclitaxel or 5FUdR treatment. Additional experiments revealed that the majority of cells detaching from the substratum after EGF (but not paclitaxel or 5FUdR) were morphologically normal and retained the capacity to readhere, suggesting that EGF-induced apoptosis involves cell detachment followed by anoikis. These observations not only indicate that EGF- and chemotherapy-induced apoptosis in this cell line involve the same downstream pathways but also suggest that detachment-induced apoptosis is responsible for the paradoxical antiproliferative effects of EGF.

Phosphorylated forms of activated caspases are present in cytosol from HL-60 cells during etoposide-induced apoptosis

Treatment of HL-60 human leukemia cells with etoposide induces apoptotic cell death and activation of at least 18 electrophoretically distinct cysteine-dependent aspartate-directed protease (caspase) isoforms, several of which differ only in their isoelectric points. The purpose of the present study was to determine whether activated caspases are phosphorylated. Phosphatase treatment of cytosolic extracts containing active caspases followed by affinity labeling with N-(N-benzyloxycarbonylglutamyl-N-biotinyllysyl)aspartic acid [(2, 6-dimethylbenzoyl)oxy] methyl ketone (Z-EK(bio)D-aomk) showed a mobility shift in several of the labeled species, suggesting that phosphorylated forms of these enzymes are present in the extracts. Metabolic labeling with 32P followed by etoposide treatment and subsequent affinity purification of affinity-labeled caspases confirmed that at least three caspase species were phosphorylated. To detect effects of the phosphorylation on enzymatic activity, caspase-mediated cleavage of aspartylglutamylvalinylaspartyl-7-amino-4-trifluoromethylcoumarin (DEVD-AFC) and poly(ADP-ribose) polymerase (PARP) by phosphorylated and dephosphorylated extracts was measured. No significant changes in Km or vmax were detected using DEVD-AFC. In contrast, a slight, but significant enhancement of PARP cleavage was observed in dephosphorylated extracts, suggesting that phosphorylation of active caspases could have an inhibitory effect on enzyme activity. These observations, which provide the first evidence that caspases are phosphoproteins, suggest that caspases may be targets for some of the growing list of protein kinases that are involved in apoptotic events.

Transition from caspase-dependent to caspase-independent mechanisms at the onset of apoptotic execution

We have compared cytoplasmic extracts from chicken DU249 cells at various stages along the apoptotic pathway. Extracts from morphologically normal "committed stage" cells induce apoptotic morphology and DNA cleavage in substrate nuclei but require ongoing caspase activity to do so. In contrast, extracts from frankly apoptotic cells induce apoptotic events in added nuclei in a caspase-independent manner. Biochemical fractionation of these extracts reveals that a column fraction enriched in endogenous active caspases is unable to induce DNA fragmentation or chromatin condensation in substrate nuclei, whereas a caspase-depleted fraction induces both changes. Further characterization of the "execution phase" extracts revealed the presence of an ICAD/DFF45 (inhibitor of caspase-activated DNase/DNA fragmentation factor)- inhibitable nuclease resembling CAD, plus another activity that was required for the apoptotic chromatin condensation. Despite the presence of active caspases, committed stage extracts lacked these downstream activities, suggesting that the caspases and downstream factors are segregated from one another in vivo during the latent phase. These observations not only indicate that caspases act in an executive fashion, serving to activate downstream factors that disassemble the nucleus rather than disassembling it themselves, but they also suggest that activation of the downstream factors (rather than the caspases) is the critical event that occurs at the transition from the latent to active phase of apoptosis.

[Caring for patients with Hickman-Broviac catheters: a case study]

Caring the patient with Hickman-Broviac catheter: a case study. The authors make a short literature review about the Hickman-Broviac catheter and after they analyse and comment about the nursing staff's knowledge and patient's self care related to this catheter.

[Multiprofessional relationship with children and family: a challenge for the staff]

This work focus the importance of the relationship existent between the multiprofessional staff, the hospitalized child and the responsible. The authors identify and comment about the positive and negative points of the pediatric units studied, as well as the orientations given by the staff and assimilated by the children and responsibles. Multiprofessional relationship X child X responsible: challenge to the staff.

Comparison of caspase activation and subcellular localization in HL-60 and K562 cells undergoing etoposide-induced apoptosis

Previous studies have shown that K562 chronic myelogenous leukemia cells are resistant to induction of apoptosis by a variety of agents, including the topoisomerase II (topo II) poison etoposide, when examined 4 to 24 hours after treatment with an initiating stimulus. In the present study, the responses of K562 cells and apoptosis-proficient HL-60 acute myelomonocytic leukemia cells to etoposide were compared, with particular emphasis on determining the long-term fate of the cells. When cells were treated with varying concentrations of etoposide for 1 hour and subsequently plated in soft agar, the two cell lines displayed similar sensitivities, with a 90% reduction in colony formation at 5 to 10 mu mol/L etoposide. After treatment with 17 mu mol/L etoposide for 1 hour, cleavage of the caspase substrate poly(ADP-ribose) polymerase (PARP), DNA fragmentation, and apoptotic morphological changes were evident in HL-60 cells in less than 6 hours. After the same treatment, K562 cells arrested in G2 phase of the cell cycle but otherwise appeared normal for 3 to 4 days before developing similar apoptotic changes. When the etoposide dose was increased to 68 mu mol/L, apoptotic changes were evident in HL-60 cells after 2 to 3 hours, whereas the same changes were observed in K562 cells after 24 to 48 hours. This delay in the development of apoptotic changes in K562 cells was accompanied by delayed release of cytochrome c to the cytosol and delayed appearance of peptidase activity that cleaved the fluorogenic substrates Asp-Glu-Val-Asp-aminotrifluoromethylcoumarin (DEVD-AFC) and Val-Glu-Ile-Asp-aminomethylcoumarin (VEID-AMC) as well as an altered spectrum of active caspases that were affinity labeled with N-(Nalpha-benzyloxycarbonylglutamyl-Nepsilon-biotin yllysyl) aspartic acid [(2,6-dimethylbenzoyl)oxy]methyl ketone [z-EK(bio)D-aomk]. On the other hand, the activation of caspase-3 under cell-free conditions occurred with indistinguishable kinetics in cytosol prepared from the two cell lines. Collectively, these results suggest that a delay in the signaling cascade upstream of cytochrome c release and caspase activation leads to a long latent period before the active phase of apoptosis is initiated in etoposide-treated K562 cells. Once the active phase of apoptosis is initiated, the spectrum and subcellular distribution of active caspase species differ between HL-60 and K562 cells, but a similar proportion of cells are ultimately killed in both cell lines.

Comparison of apoptosis in wild-type and Fas-resistant cells: chemotherapy-induced apoptosis is not dependent on Fas/Fas ligand interactions

The Fas/Fas ligand (FasL) pathway is widely involved in apoptotic cell death in lymphoid and nonlymphoid cells. It has recently been postulated that many chemotherapeutic agents also induce cell death by activating the Fas/FasL pathway. In the present study we compared apoptotic pathways induced by anti-Fas or chemotherapeutic agents in the Jurkat human T-cell leukemia line. Immunoblotting showed that treatment of wild-type Jurkat cells with anti-Fas or the topoisomerase II-directed agent etoposide resulted in proteolytic cleavage of precursors for the cysteine-dependent aspartate-directed proteases caspase-3 and caspase-7 and degradation of the caspase substrates poly(ADP-ribose) polymerase (PARP) and lamin B1. Likewise, affinity labeling with N-(N(alpha)-benzyloxycarbonylglutamyl-N(epsilon)-biotinyllysyl+ ++)aspartic acid [(2,6-dimethyl-benzoyl)oxy]methyl ketone [Z-EK(bio)D-amok] labeled the same five active caspase species after each treatment, suggesting that the same downstream apoptotic pathways have been activated by anti-Fas and etoposide. Treatment with ZB4, an antibody that inhibits Fas-mediated cell death, failed to block etoposide-induced apoptosis, raising the possibility that etoposide does not initiate apoptosis through Fas/FasL interactions. To further explore the relationship between Fas- and chemotherapy-induced apoptosis, Fas-resistant Jurkat cells were treated with various chemotherapeutic agents. Multiple independently derived Fas-resistant Jurkat lines underwent apoptosis that was indistinguishable from that of the Fas-sensitive parental cells after treatment with etoposide, doxorubicin, topotecan, cisplatin, methotrexate, staurosporine, or gamma-irradiation. These results indicate that antineoplastic treatments induce apoptosis through a Fas-independent pathway even though Fas- and chemotherapy-induced pathways converge on common downstream apoptotic effector molecules.

[Characteristics of intensive care units in Sao Paulo]

This study is the first part in a series of the articles reporting results of a project conducted to analyse the structural resources of ICUs in São Paulo city. This article describes the characteristics of those Units, considering the quantity and geographic location, bed number, maintainer entity, type of assistance, type of client, as well the percentage of beds usage and length of stay. Forty three ICUs were analysed and a questionnaire answered by the ICU nurse coordinator was used to collect data. The results showed that the number of ICUs in the hospital varied from 1 to 4, being more frequently those with only one ICU (68.8%). 79.2% of the Units were in private hospitals, located in the central area of the city. ICU beds represented 8.0% of the total hospital beds and there was an average of 10 beds per Unit. There was a predominance of general ICUs (60.5%), destined only for adult patients (51.2%) and for clinical-surgical treatment (95.3%). The percentage of beds usage in majority of ICU was between 80 to 100% and the length of stay was 4,5 days.

Activation of multiple interleukin-1beta converting enzyme homologues in cytosol and nuclei of HL-60 cells during etoposide-induced apoptosis

Recent genetic and biochemical studies have implicated cysteine-dependent aspartate-directed proteases (caspases) in the active phase of apoptosis. In the present study, three complementary techniques were utilized to follow caspase activation during the course of etoposide-induced apoptosis in HL-60 human leukemia cells. Immunoblotting revealed that levels of procaspase-2 did not change during etoposide-induced apoptosis, whereas levels of procaspase-3 diminished markedly 2-3 h after etoposide addition. At the same time, cytosolic peptidase activities that cleaved DEVD-aminotrifluoromethylcoumarin and VEID-aminomethylcoumarin increased 100- and 20-fold, respectively; but there was only a 1. 5-fold increase in YVAD-aminotrifluoromethylcoumarin cleavage activity. Affinity labeling with N-(Nalpha-benzyloxycarbonylglutamyl-Nepsilon-biotin yllysyl)aspartic acid [(2,6-dimethylbenzoyl)oxy]methyl ketone indicated that multiple active caspase species sequentially appeared in the cytosol during the first 6 h after the addition of etoposide. Analysis on one- and two-dimensional gels revealed that two species comigrated with caspase-6 and three comigrated with active caspase-3 species, suggesting that several splice or modification variants of these enzymes are active during apoptosis. Polypeptides that comigrate with the cytosolic caspases were also labeled in nuclei of apoptotic HL-60 cells. These results not only indicate that etoposide-induced apoptosis in HL-60 cells is accompanied by the selective activation of multiple caspases in cytosol and nuclei, but also suggest that other caspase precursors such as procaspase-2 are present but not activated during apoptosis.

CrmA/SPI-2 inhibition of an endogenous ICE-related protease responsible for lamin A cleavage and apoptotic nuclear fragmentation

CrmA, a poxvirus gene product with a serpin-like structure, blocks a variety of apoptotic death events in cultured cells. Based on the ability of CrmA to inhibit the interleukin-1beta converting enzyme in vitro, it has been speculated that interleukin-1beta converting enzyme-related proteases (caspases) essential for apoptosis are the cellular targets of CrmA. Here we found that rabbitpox virus CrmA/SPI-2 inhibits the cleavage of lamin A mediated by a caspase in our cell-free system of apoptosis. In the presence of CrmA/SPI-2, nuclear apoptosis in vitro was blocked at an intermediate stage after collapse of the chromatin against the nuclear periphery and before nuclear shrinkage and disintegration into apoptotic body-like fragments. Using N-(acetyltyrosinylvalinyl-Nepsilon-biotinyllysyl) aspartic acid [(2,6-dimethylbenzoyl)oxy] methyl ketone, which derivatizes the active forms of caspases, we could show that one of five caspases active in the extracts is inhibited both by CrmA/SPI-2 and by a peptide spanning the lamin A apoptotic cleavage site. These results reveal that CrmA/SPI-2 can inhibit a caspase responsible both for lamin A cleavage and for the nuclear disintegration characteristic of apoptosis.

[Quality of life of persons with chronic illness]

The present study has the following objectives: to identify the significance of the quality of life of people with chronic illness and verify its interference in their quality of life. We have studied 71 people of both sexes, attended in the clinical settings of 2 public hospitals. The most common diagnoses were high blood pressure and diabetes mellitus. The significance of quality of life to interviewed people was related mainly to material comfort (40.9%); physical comfort (23.9%) and emotional comfort (11.2%). Chronic illness interfered in their quality of life because it has changed, especially, their physical capacity (67.6%), their work/study/home activities (64.8%) and their self-esteem (53.5%). Based on the results, we emphasize the importance of nursing in the adaptation process of people and their relatives considering the limitations of chronic illness.