Influence of the dopaminergic system, CREB, and transcription factor-κB on cocaine neurotoxicity

Cocaine is a widely used drug and its abuse is associated with physical, psychiatric and social problems. Abnormalities in newborns have been demonstrated to be due to the toxic effects of cocaine during fetal development. The mechanism by which cocaine causes neurological damage is complex and involves interactions of the drug with several neurotransmitter systems, such as the increase of extracellular levels of dopamine and free radicals, and modulation of transcription factors. The aim of this review was to evaluate the importance of the dopaminergic system and the participation of inflammatory signaling in cocaine neurotoxicity. Our study showed that cocaine activates the transcription factors NF-κB and CREB, which regulate genes involved in cellular death. GBR 12909 (an inhibitor of dopamine reuptake), lidocaine (a local anesthetic), and dopamine did not activate NF-κB in the same way as cocaine. However, the attenuation of NF-κB activity after the pretreatment of the cells with SCH 23390, a D1 receptor antagonist, suggests that the activation of NF-κB by cocaine is, at least partially, due to activation of D1 receptors. NF-κB seems to have a protective role in these cells because its inhibition increased cellular death caused by cocaine. The increase in BDNF (brain-derived neurotrophic factor) mRNA can also be related to the protective role of both CREB and NF-κB transcription factors. An understanding of the mechanisms by which cocaine induces cell death in the brain will contribute to the development of new therapies for drug abusers, which can help to slow down the progress of degenerative processes.

Cardiac antiapoptotic and proproliferative effect of recombinant human erythropoietin in a moderate stage of chronic renal failure in the rat

Objective:

Recombinant human erythropoietin (rhEPO) therapy under circumstances of moderate chronic renal failure (CRF), with yet lower kidney and heart lesion, may have a protective cardiac effect beyond the correction of anemia, whose mechanism deserves better elucidation, namely by clarifying the impact on gene expression profile of markers of apoptosis, inflammation, proliferation, angiogenesis, and lesion/stress in the heart.

Materials and Methods:

Four groups of rats were studied over a period of 15 weeks (n=7 each): control—without surgery and without drug treatment; rhEPO—treated with 50 IU/kg/week of rhEPO—beta; CRF—submitted to partial nephrectomy (3/4); CRF + rhEPO—CRF with rhEPO treatment after the 3rd week of surgery. The heart was collected in order to evaluate the gene expression, by real-time qPCR, of markers of apoptotic machinery, inflammation/immunology, proliferation/angiogenesis, and lesion/stress.

Results:

The main findings obtained were (a) CRF rats have demonstrated overexpression of EPO-R in the heart without changes on EPO expression, together with overexpression of Bax/Bcl2 ratio, PCNA, and IL-2; (b) rhEPO therapy on the heart of the rats with CRF induced by partial 3/4 nephrectomy promoted nonhematopoietic protection, demonstrated by the apoptosis prevention, viewed by the Bax/Bcl2 balance, by the promotion of proliferation, due to PCNA increment, and by the immunomodulatory action, expressed by a trend to prevent the IL-2 increment.

Conclusion:

In this model of moderate CRF, rhEPO treatment showed important cardiac nonhematopoietic effects, expressed mainly by the antiapoptotic and the proproliferative action, suggesting that early rhEPO therapy in moderate stages of CRF might have further therapeutic benefits.

The presence of resistance mutations to protease and polymerase inhibitors in Hepatitis C virus sequences from the Los Alamos databank

Several new direct-acting antiviral (DAA) drugs are in development for chronic hepatitis C viral (HCV) infection, and NS3-NS4A serine protease and the NS5B RNA-dependent RNA polymerase have been the major targets. HCV variants displaying drug-resistant phenotypes have been observed both in vitro and during clinical trials. Our aim was to characterize amino acid changes at positions previously associated with resistance in protease (NS3) and polymerase (NS5B) regions from treatment-naïve HCV patients infected with genotypes 1a, 1b and 3a. All 1383 NS3 protease sequences (genotype 1a = 680, 1b = 498 and 3a = 205) and 806 NS5B polymerase sequences (genotypes 1a = 471, 1b = 329, 3a = 6) were collected from Los Alamos databank. Genotype 3a protease sequences showed the typical low-level resistance mutation V36L. NS3 sequences from other genotypes presented mutations on positions 36, 39, 41, 43, 54, 80, 109, 155 and 168 in a frequency lower than 2%, except for the mutation Q80R found in 35% of genotype 1a isolates. Polymerase sequences from genotype 3a patients showed five typical mutations: L419I, I424V, I482L, V499A and S556G. Two positions presented high polymorphism in the NS5B region from genotype 1a (V499A) and genotype 1b (C316N) subjects. Our results demonstrated a natural profile of genotype 3a that can be associated with the pre-existence of HCV variants resistant to first-generation protease inhibitors and to non-nucleoside polymerase inhibitors. Likewise, genotype 1b isolates and genotype 1a sequences exhibited pre-existing mutations associated with resistance to Palm II and Thumb I polymerase inhibitors, respectively.

Conversion to everolimus in kidney transplant recipients: to believe or not believe?

INTRODUCTION

Immunosuppression with calcineurin inhibitors (CNI) in renal transplantation is associated with chronic graft dysfunction, increased cardiovascular risk, and malignancies. Everolimus (EVR) appears to permit a CNI-sparing regimen among stable kidney recipients.

AIM

The aim of this study was to analyze the efficacy and safety of conversion from CNI to EVR.

MATERIAL AND METHODS

This was a retrospective registry-based study of all kidney transplant recipients converted from CNI to EVR between 2006 and 2010. One hundred fifty-one patients, including 69.5% males and with an overall mean age of 50.2 ± 12.7 years, underwent conversion to EVR at 37.0 ± 49.8 (16) months after transplantation with 33.7% during the first 6 months. Reasons for conversion included: CNI nephrotoxicity prevention (54.3%), chronic graft dysfunction (25.8%), malignant tumors (10.6%), CNI-adverse reactions (6.6%), and biopsy-proven CNI nephrotoxicity (2.6%). During a follow-up of 17.9 ± 9.9 months (range, 6-58.5), 18 patients (11.9%) were reconverted to CNI, 2 died with functioning grafts, and 2 lost kidney function.

RESULTS

We observed a significant (P < .001) increase in estimated glomerular filtration rate-Modification of Diet in Renal Disease (eGFR-MDRD) by 11.3% within 6 months: 56.7 ± 22.1 to 64.1 ± 23.4 mL/min/1.73 m(2). At final evaluation it was 13.7%, namely, to 65.5 ± 23.0 mL/min/1.73 m(2). At the end of follow-up the proportion of patients with >300 mg/d proteinuria increased from 7.9% to 23.3% (P = .001). Dyslipidemia prevalence increased from 69.5% to 77.5% (P = not significant [NS]) and arterial hypertension increased from 49% to 65.9% (P < .001) at the end of follow-up. Other reported side effects included oral ulcers (2.6%), edema (5.3%), interstitial pneumonitis (1.3%), and toxic hepatitis (1.3%), some of them leading to EVR discontinuation.

CONCLUSION

In our population, renal function improved significantly after conversion from CNI to EVR. Although side effects were common, most were mild, withdrawal of EVR was necessary in a low percentage of cases. EVR appears to be an effective, safe alternative to CNI for maintenance therapy in selected kidney transplant recipients.

Uncommon cause of chest pain in a renal transplantation patient with autosomal dominant polycystic kidney disease: a case report

Autosomal dominant polycystic kidney disease (ADPKD) is a common cause of end-stage renal disease (ESRD) and, because of its intrinsic systemic involvement, its treatment can be a medical and surgical challenge. This condition is often associated with the presence of hepatic cysts and their prevalence generally increases with age. Most patients remain asymptomatic, but some of these will develop complications associated with enlargement and infection of their cysts. Chest pain is a rare manifestation of these complications and, after exclusion of more common cardiovascular and pulmonary causes, should raise the suspicion of an infected hepatic cyst in these patients. We report the case of a 62-year-old male who underwent a kidney transplantation from a cadaveric donor in 1997 (etiology of the ESRD was ADPKD), and was admitted to the emergency department with complaints of chest pain radiating to both shoulders and the interscapular region. An echocardiogram was showed compression of the right atrium by a large liver cyst without associated ventricular dysfunction. Computer tomography-guided drainage of the cyst was performed and an Enterobacter aerogenes sensitive to carbamapenemes was isolated from respective cultures. The patient presented a favorable clinical outcome with prolonged administration of antibiotic therapy according to the antibiotic susceptibility testing. There was no need for surgical intervention.

Delayed presentation of vernix caseosa peritonitis

INTRODUCTION

Vernix caseosa peritonitis (VCP) is a rare and poorly recognised condition resulting from a sustained foreign body reaction to the vernix caseosa of the baby. This case-based review aims to highlight its importance for any medical team managing patients with peritonitis who have undergone a recent Caesarean section.

CASE REPORT

A 31-year-old woman presented 5 weeks after a Caesarean section with symptoms and signs of peritonitis.

CONCLUSIONS

Laparotomy and peritoneal lavage is the mainstay of treatment for VCP. Knowledge of the condition may stop inadvertent resection of normal intra-abdominal organs. Greater awareness of VCP is required to ensure earlier recognition as patients can recover well following timely operative intervention.

C4d deposits in acute "cell-mediated" rejection: a marker for renal prognosis?

BACKGROUND

Accumulation of C4d along peritubular capillaries (PTC) of renal allografts is normally attributed to antibody-mediated rejection. The prognostic implication of these deposits associated with "cell-mediated" rejection on graft survival remains uncertain. Our study aims to evaluate the impact of C4d deposits along PTC of patients with acute cell- mediated rejection on graft function and survival.

METHODS

We retrospectively analyzed patients transplanted between 2005 and 2010 with histopathologic diagnosis of acute rejection (AR). Eleven patients with "pure" antibody-mediated rejection were excluded. The remaining 79 patients were divided into two groups according to type of AR by Banff 2003 criteria: type I (69.6%) versus type II (30.4%). In each group, comparisons were made between C4d-negative (-) and C4d-positive (+) biopsies.

RESULTS

Fifty-five patients presented with type I AR: 35 (63.6%) C4d- and 20 (36.4%) C4d+. Twenty-four patients presented with type II AR: 13 (54.2%) C4d- and 11 (45.8%) C4d+. In the type I AR group, graft survival at the first and second years was similar in C4d- and C4d+ patients (94% and 91% versus 75% and 75%, respectively, log-rank P = .26). No differences were encountered in estimated glomerular filtration rate (eGFR) between subgroups at the first, second, and final years of follow-up. Graft loss occurred in 14.7% of C4d- patients versus 25% in C4d+ patients (P = NS). In the type II AR group, graft survival at the first and second years was similar in C4d- and C4d+ patients (85% and 85% versus 72% and 61%, respectively, log-rank P = .50). No differences were encountered in eGFR between subgroups at the first, second, and final years of follow-up. Graft loss occurred in 30.8% of C4d- patients versus 45.5% in C4d+ patients (P = NS).

CONCLUSION

Our results suggest that detection of C4d staining in acute "cell-mediated" rejection does not imply a worse renal prognosis.

Growth and survival of the pearl oyster Pteria hirundo (L.,1758) in an intermediate stage of culture in Santa Catarina, Brazil

There are no records in Brazil for the culture of Pteridae family oysters, genus Pteria and Pinctada. The intermediate culture can be considered one of the critical stages during the oyster farming. The changes in life conditions from a semi-closed environment provided by the collector to the structures utilized for the growth represents a considerable stress factor to which the animals are subjected. The goal of the present study was to evaluate the growth and survival of the pearl oyster Pteria hirundo (Linnaeus, 1758) kept in intermediate lanterns. Seeds of P. hirundo, obtained through larviculture carried out at the Marine Molluscs Laboratory (UFSC), southern Brazil were detached from the collectors, transferred and kept in an intermediate culture system (oyster lantern). During 6 months, growth (dorso-ventral height - DVH in mm) and survival (%) were evaluated. Two size classes were tested: medium (M), between 3.4 and 4.4 mm, and large (L), bigger than 4.5 mm. The density of occupation in each floor of the lantern was 50%. At the end of the experiment, the survivals observed were 90 and 94% for the sizes M and L, respectively. Medium juveniles of Pteria hirundo had an average (Std) increase of 16.1 (±4.38) mm in the dorso-ventral height, and large juveniles an average increase of 11.4 (±3.77) mm after six months of experiment. The results observed during the intermediate stage of cultivation indicate that Pteria hirundo presents survival and growth similar to other species of pearl oysters traditionally used in the pearl industry in several countries.

Renal transplantation in recipients over 65 years old

BACKGROUND AND PURPOSE

Older patients on hemodialysis have become candidates for renal transplantation, particularly in the period of increasing numbers of marginal donors. The purpose of this study was to evaluate short-term and long-term results of renal transplantation among recipients ≥65 years old for comparison with these in younger patients.

PATIENTS AND METHODS

We retrospectively studied 1,796 renal transplantations performed between June 1991 and May 2010, dividing the sample into 2 groups: ≥65 years old (n = 89) versus <65 years old (n = 1,707).

RESULTS

The mean ages were 42.17 and 67.45 years for the younger and older groups, respectively. Time of pretransplantation dialysis was significantly greater among the older group (52.76 vs 47.69 mo). There were no differences between the 2 groups regarding donor age, donor renal function, or cold ischemia times. After a mean follow-up of 73.37 versus 39.73 months for the younger versus older groups, respectively, we observed differences in initial graft function, with a greater rate of delayed graft function in the ≥65 group (28.1% vs 17.8%), and in acute rejection rate, which was higher among the younger group (19.4% vs 10.1%). Initial creatinine was better for the older group (1.71 vs 2.10 mg/dL), but similar between the groups at 10 years. Graft and patient survivals at 1, 5, and 10 years were lower among the older group. When analyzing graft survival censored for death with a functioning kidney, there were no differences between the younger and older groups: It was at 1, 5, and 10 years, namely 93.6% versus 90.6%, 87% versus 80.8%, and 76.7% versus 70.1%, respectively.

CONCLUSIONS

Selected recipients ≥65 years of age show good outcomes of transplantation.

Teaching systems biology

Advances in systems biology are increasingly dependent upon the integration of various types of data and different methodologies to reconstruct how cells work at the systemic level. Thus, teams with a varied array of expertise and people with interdisciplinary training are needed. So far this training was thought to be more productive if aimed at the Masters or PhD level. At this level, multiple specialised and in-depth courses on the different subject matters of systems biology are taught to already well-prepared students. This approach is mostly based on the recognition that systems biology requires a wide background that is hard to find in undergraduate students. Nevertheless, and given the importance of the field, the authors argue that exposition of undergraduate students to the methods and paradigms of systems biology would be advantageous. Here they present and discuss a successful experiment in teaching systems biology to third year undergraduate biotechnology students at the University of Lleida in Spain. The authors' experience, together with that from others, argues for the adequateness of teaching systems biology at the undergraduate level. [Includes supplementary material].