pH-sensitive polymers that enhance intracellular drug delivery in vivo.

Cytosolic delivery from endosomes is critical for those drugs that are susceptible to attack by lysosomal enzymes, such as DNA, RNA, oligonucleotides, proteins and peptides. Therefore, we have designed pH-sensitive, membrane-disruptive polymers to enhance the release of drugs from the acidic endosomal compartment to the cytoplasm. We have found that one polymer in particular, poly(propylacrylic acid) (PPAA), is very effective at membrane disruption at pHs below 6.5, based on hemolysis studies. PPAA also significantly enhances in vitro transfections of lipoplex formulations in cell culture, and does so in the presence of as much as 50% serum. In this study, we have extended our in vitro hemolysis and cell culture studies to an in vivo murine excisional wound healing model. A pilot study with a green fluorescent protein (GFP)-encoding plasmid indicated that injection of formulations containing PPAA into healing wounds resulted in increased GFP expression. Subsequently, by administering sense and antisense DNA for the angiogenesis inhibitor thrombospondin-2 (TSP2), we were able to alter the wound healing response in TSP2-null and wild type mice, respectively. Our findings showed that when PPAA was added to lipoplex formulations, expression of TSP2 was enhanced in TSP2-null mice compared to control formulations. These results show that PPAA can enhance in vivo transfections and that inhibition of TSP2 expression may lead to improved wound healing. These results suggest that PPAA can provide significant improvements in the in vivo efficacy of drugs such as DNA.     

Retargeting of adenoviral vectors to neurons using the Hc fragment of tetanus toxin

The Hc fragment of tetanus toxin (Hc) retains the specific nerve cell binding and transport properties of the holotoxin, but lacks any toxicity. We are investigating the potential for utilising its neurotropism for targeted gene delivery to the central nervous system. Previously we reported the use of Hc-polylysine conjugates for selective gene transfer into neuronal cells in vitro. However, as attempts to apply these constructs in vivo were not successful, we have extended these studies to modification of the tropism of adenoviral vectors. Either Hc-polylysine conjugates or the Fab fragment of a neutralising anti-knob antibody covalently bound to Hc were attached to the virus. Infection of neuronal and non-neuronal cell lines with retargeted virus showed highly increased neuronal cell selectivity, but no significant enhancement of gene delivery into these cells. High concentrations of free Hc blocked the infectivity of the retargeted vector efficiently. Intramuscular injection of retargeted virus into mouse tongues resulted in selective gene transfer to the neurons of the hypoglossal nucleus, where no pathological changes were observed. As differentiated neurons do not undergo cell division, appropriate vectors carrying a thymidine kinase gene, which allows selective elimination of dividing cells, may be exploitable for the treatment of tumours of the central nervous system. The demonstrated suitability of the Hc fragment of tetanus toxin as targeting moiety for viral vectors also indicates a potential for gene therapy of inherited neurodegenerative diseases such as spinal muscular atrophy.     

Quality of life and time perspective in inflammatory bowel disease patients

Purpose

Numerous studies have shown the impact of inflammatory bowel disease (IBD) on patient quality of life (QoL), but no research has yet examined the impact of time’s experience in the assessment of QoL in IBD. Our goal is to explore the links between QoL and time perspective (TP) and the role of TP as a determinant of QoL.

Methods

Data were collected from 156 patients who completed a questionnaire comprising a generic measure (SF-12) and a specific measure (Inflammatory Bowel Disease Questionnaire) of QoL, a measure of TP (ZTPI) and a collection of socio-demographic and medical data.

Results

Correlational analyses illustrated the links between TP and QoL. Regression analyses revealed that records of Past-negative and Present-hedonistic perspectives predicted QoL. Past-negative time perspective seemed to have a deleterious impact, while a Present-hedonistic time perspective predicted a better QoL, and this was irrespective of the level of severity of the disease.

Conclusions

These results suggest the importance of considering TP as a determinant of psychological QoL. They corroborate earlier findings on the relationship between TP and QoL associated with other pathologies. The past-negative register, which indicates rumination, tells us about the importance of considering the psychological experience of time in order to improve the QoL of patients.     

Urogenital anomalies in human male fetuses

BACKGROUND: There are few studies in the literature performed in human fetuses evaluating the incidence of genitourinary anomalies. AIMS: Analyze the incidence of congenital urogenital malformations in human male fetuses. STUDY DESIGNS AND SUBJECTS: We analyzed 166 human male fetuses well preserved. The gestational age was determined in weeks post conception (WPC) according to the foot length criterion and ranged from 10 to 35 WPC. The fetuses were dissected with the aid of a stereoscopic lens with 2.5x magnification. We performed abdominal and pelvic incisions to expose the urogenital organs. We studied the incidence of renal, ureteral, vesicle, urethral, testicular, epididymal, vas deferens, prostate and penile anomalies. RESULTS: Of the 166 fetuses, 7 (4.2%) presented some kind of anomaly of the urogenital system. Renal anomalies were found in two fetuses (1.2%). Unilateral renal agenesis was found in a 25 WPC fetus. Horseshoe kidney was found in a 20 WPC fetus. In a 23 WPC fetus (0.6%) the two testes were absent. Epididymal disjunction anomalies were found in four fetuses (2.4%). CONCLUSIONS: The urogenital anomalies in human male fetuses are rare and have an incidence around 4%.     

A peptide-morpholino oligomer conjugate targeting Staphylococcus aureus gyrA mRNA improves healing in an infected mouse cutaneous wound model

Management of skin wound infections presents a serious problem in the clinic, in the community, and in both civilian and military clinical treatment centers. Staphylococcus aureus is one of the most common microbial pathogens in cutaneous wounds. Peptide-morpholino oligomer (PMO) conjugates targeted to S. aureus gyrase A mRNA have shown the ability to reduce bacterial viability by direct site-specific mRNA cleavage via RNase P. As a treatment, these conjugates have the added advantages of not being susceptible to resistance due to genetic mutations and are effective against drug resistant strains. While this strategy has proven effective in liquid culture, it has yet to be evaluated in an animal model of infected surface wounds. In the present study, we combined PMO conjugates with a thermoresponsive gel delivery system to treat full-thickness mouse cutaneous wounds infected with S. aureus. Wounds treated with a single dose of PMO conjugate displayed improved healing that was associated with increased epithelialization, reduced bacterial load, and increased matrix deposition. Taken together, our findings demonstrate the efficacy and flexibility of the PMO conjugate drug delivery system and make it an attractive and novel topical antimicrobial agent.     

Using partial decision trees to predict Parkinson's symptoms: a new approach for diagnosis and therapy in patients suffering from Parkinson's disease

In this work we present a method based on partial decision trees and association rules for the prediction of Parkinson's disease (PD) symptoms. The proposed method is part of the PERFORM system. PERFORM is used for the treatment of PD patients and even advocate specific combinations of medications. The approach presented in this paper is included in the data miner module of PERFORM. A patient performs some initial examinations and the module predicts the future occurrence of the symptoms based on the initial examinations and medications taken. Using the method, the expert can prescribe specific medications that will not cause, or postpone the appearance of specific symptoms to the patient. The approach employed is able to provide interpretation for the predictions made, by providing rules. The models have been developed and evaluated using real patient's data and the respective results are reported. Another functionality of the data miner module is the extraction of rules through a user friendly interface using association rule mining algorithms. These rules can be used for the prediction analysis of patient's reaction to certain treatment plans. The accuracy of the symptoms' prediction ranges from 57.1 to 77.4%, depending on the symptom.     

Cirrhosis in children and adolescents: An overview

Several conditions, especially chronic liver diseases, can lead to cirrhosis in children and adolescents. Most cases in clinical practice are caused by similar etiologies. In infants, cirrhosis is most often caused by biliary atresia and genetic-metabolic diseases, while in older children, it tends to result from autoimmune hepatitis, Wilson’s disease, alpha-1-antitrypsin deficiency and primary sclerosing cholangitis. The symptoms of cirrhosis in children and adolescents are similar to those of adults. However, in pediatric patients, the first sign of cirrhosis is often poor weight gain. The complications of pediatric cirrhosis are similar to those observed in adult patients, and include gastrointestinal bleeding caused by gastroesophageal varices, ascites and spontaneous bacterial peritonitis. In pediatric patients, special attention should be paid to the nutritional alterations caused by cirrhosis, since children and adolescents have higher nutritional requirements for growth and development. Children and adolescents with chronic cholestasis are at risk for several nutritional deficiencies. Malnutrition can have severe consequences for both pre- and post-liver transplant patients. The treatment of cirrhosis-induced portal hypertension in children and adolescents is mostly based on methods developed for adults. The present article will review the diagnostic and differential diagnostic aspects of end-stage liver disease in children, as well as the major treatment options for this condition.     

Cholinergic System and Oxidative Stress Changes in the Brain of a Zebrafish Model Chronically Exposed to Ethanol

Ethanol is a widely used drug, and excess or even moderate consumption of ethanol is associated with changes in several neurotransmitter systems, including the cholinergic system. The incidence of alcoholic dementia and its insults are well supported by multiple studies, although the mechanisms of neurotoxicity are still poorly understood. Considering that zebrafish have a complete central nervous system (CNS) and that several signaling systems have already been identified in zebrafish, this neurotoxicological model has become useful. In the present study, we investigated the long-term effects of ethanol consumption on the cholinergic system, on oxidative stress, and on inflammatory parameters in the zebrafish brain. Animals were exposed to 0.5% (v/v) ethanol for 7, 14, and 28 days. Ethanol inhibited choline acetyltransferase activity after 7 and 14 days but not after 28 days. Acetylcholinesterase activity did not change after any of the exposure periods. When compared to the control group, thiobarbituric acid reactive species and dichlorodihydrofluorescein levels were increased after chronic ethanol exposure. Antioxidant activity promoted by the CAT/SOD ratio was altered after chronic ethanol exposure, suggesting that EtOH can induce oxidative damage in the zebrafish brain. In contrast, nitrate and nitrite levels and sulfhydryl content were not altered. Ethanol did not modify gene expression of the inflammatory cytokines il-1b, il-10, or tnf-α in the zebrafish brain. Therefore, the cholinergic system and the oxidative balance were targeted by chronic ethanol toxicity. This neurochemical regulatory mechanism may play an important role in understanding the effects of long-term ethanol consumption and tolerance in zebrafish model studies.     

An assessment of the Family Health Program in municipalities of Northeast Brazil: old and new challenges

This article presents part of the results from the Baseline Studies, an evaluative research conducted in 21 municipalities with more than 100,000 inhabitants each, in three States of Northeast Brazil. The overall objective was to assess experiences in the implementation of the Family Health Program (FHP), with a focus on inductions in the PROESF. An implementation analysis was performed, using the case study method. The analysis focused on these dimensions: political-institutional, health organization, and comprehensive care. Outstanding advances included: prioritize the FHP in high-risk areas; institutional learning, with qualification of managers and teams; definition of institutional levels for regulating the FHP; and health team-user bonds and positive perceptions concerning the program. Challenges included: strengthening of local policy and decision-making capacity; allocation of primary care resources; greater employment security for human resources; effective implementation of the health care network; strengthening of social participation; upgrading of monitoring and evaluation for decision-making; receptivity; waiting lines for tests, appointments, and hospital admissions; implementation of teamwork; health promotion and inter-sector activities.