Serum-resistant lipopolyplexes for gene delivery to liver tumour cells.

In this study, an efficient non-viral gene transfer system has been developed by employing polyethylenimine (PEI 800, 25 and 22kDa) and DOTAP and cholesterol (Chol) as lipids (lipopolyplex), at three different lipid/DNA molar ratios (2/1, 5/1 and 17/1) by using five different protocols of formulation. Condensation assays revealed that PEI of 800, 25 and 22kDa were very effective in condensing plasmid DNA, leading to a complete condensation at N/P ratios above 4. Addition of DOTAP/Chol liposomes did not further condense DNA. Increasing the molar ratio lipid/DNA in the complex resulted in higher positive values of the zeta-potential, while the particle size increased in some protocols, but not in others. High molecular weight PEI (800kDa) used in the formulation of lipopolyplexes lead to a bigger particle size, compared to that obtained with smaller PEI species, whether branched (25kDa) or linear (22kDa). These vectors were also highly effective in protecting DNA from attack by DNAse I. Transfection activity was maximal by using protocols 3 and 4 and a lipid/DNA molar ratio of 17/1. These complexes showed high efficiency in gene delivery of DNA to liver cancer cells, even in the presence of high concentration of serum (60% FBS). On the other hand, complexes formed with linear PEI (22kDa) were more effective than lipopolyplexes containing branched PEI (800 or 25kDa). The complexes resulted to be much more efficient than conventional lipoplexes (cationic lipid and DNA) and polyplexes (cationic polymer and DNA). The same behaviour was observed for complexes prepared in the presence of the therapeutic gene pCMVIL-12. Toxicity assays revealed a viability higher than 80% in all cases, independently of the protocol, molar ratio (lipid/DNA), molecular weight and type of PEI.     

Self-administered heroin and cocaine combinations in the rat: additive reinforcing effects-supra-additive effects on nucleus accumbens extracellular dopamine.

The concurrent use of cocaine and opiate combinations (speedball) has increased since the 1970s and now represents a growing subset of intravenous drug abusers. An isobolographic analysis was applied to the ascending limb of the dose-effect curves for rat self-administration of cocaine, heroin, and their combination to determine the nature of the interaction. The addition of heroin to cocaine shifted the dose-effect curve for self-administration to the left, and the modulation in reinforcing efficacy of the combination of cocaine and heroin was found to be additive. A second experiment used microdialysis to determine the effects of this drug combination on nucleus accumbens (NAc) extracellular levels of dopamine ([DA](e)) in rats self-administering low doses of cocaine, heroin, or cocaine/heroin combinations. These doses of cocaine and cocaine/heroin combinations significantly increased NAc [DA](e), while heroin alone did not. The ratio of the % baseline of [DA](e) (or the dialysate concentrations of DA) to cocaine in the dialysate was higher during self-administration of cocaine/heroin combinations than with cocaine alone. These data indicate that although the interaction between cocaine and heroin in maintaining self-administration is additive, a potentiation of NAc dopaminergic neurotransmission is present, suggesting that NAc [DA](e) may not be a direct measure of reinforcing efficacy and/or it is not central to the mediation of the self-administration of this drug combination.     

Acute gastroenteritis outbreaks in closed and semi-closed facilities during 2017 in Catalonia,Spain

Acute gastroenteritis (AGE) is a leading cause of disease worldwide. The aim of this prospective observational study is to describe the epidemiology of AGE in closed and semi-closed institutions in Catalonia. In 2017, 151 outbreaks were reported; 30.5% occurred in closed and semi-closed institutions; 71.7% caused by norovirus (NoV) (1532) cases. Person-to-person transmission accounted for 75.8% of NoV outbreaks vs 46.1% in non-NoV outbreaks (p?<?0.001). Attack rate for NoV outbreaks was 33.1% vs 14.3% for non-NoV outbreaks (RR?=?2.3; 95%CI: 2.0–2.7). The high number of affected underscores prompt and intense preventive measures to avoid the extension and perpetuation of outbreaks in these settings.

     

Expired air carbon monoxide concentration in mothers and their spouses above 5 ppm is associated with decreased fetal growth

BACKGROUND: Smoking during pregnancy is associated with reduced birthweight; this relation can be reversed by smoking cessation. Some but not all previous studies have shown that smoking reduction (measured as cigarettes/day or urinary cotinine) may also improve birthweight. The relationship between maternal and spouses' expired air carbon monoxide (CO) concentrations (EACO) on fetal growth has not yet been evaluated. METHODS: Eight hundred fifty-six smoking and nonsmoking pregnant women were followed during their pregnancy. Their EACO was determined in the first trimester and during delivery. The spouses' EACO were also measured at delivery. The main outcome measure was the infants' birthweight. Secondary measures included head circumference, Apgar score, and heart rate at delivery. Cord blood fetal carboxyhemoglobin (FCOHb) served as internal control. RESULTS: Birthweight dose-dependently and significantly decreased with increasing level of maternal (0-5: 3406 +/- 32; 6-10: 3048 +/- 57; 11-20: 2858 +/- 54; >20 ppm: 2739 +/- 34 g, P < 0.0001) or spouses' EACO (0-5: 3546 +/-25; 6-10: 3484 +/- 51; 11-20: 3309 +/- 47; >20 ppm: 3190 +/- 57 g, P < 0.0001). Even the birthweight of newborns whose mother had EACO between 6 and 10 ppm was significantly lower than the birthweight of newborns whose mother had an EACO between 0 and 5 ppm. Spouses' EACO of delivering women with EACO of 0-5 ppm showed similar effect. Head circumference, Apgar score, and normal term gestational age decreased also significantly with increasing maternal or spouses' EACO. CONCLUSIONS: Both maternal and spouses' EACO measured during delivery, a proxy of EACO during pregnancy, were dose-dependently and inversely associated with fetal growth. Even low maternal (6 to 10 ppm) or spouses' (11 to 20 ppm) EACO may be associated with significantly lower birthweight.     

Quantitative real-time polymerase chain reaction based on single copy gene sequence for detection of periodontal pathogens

OBJECTIVE: To develop a method for quantification of Actinobacillus actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg) and Tannerella forsythensis (Tf) from subgingival plaque samples based on TaqMan real-time polymerase chain reaction (PCR) technology. MATERIAL AND METHODS: Bacterial cells from these species were obtained after culturing reference strains and were counted microscopically. Cellular suspensions in Tris-EDTA buffer were used for DNA extraction after boiling for 20 min. Primers for PCR were selected from sequences of the LktC (Aa), Arg-gingipain (Pg) and BspA antigen (Tf) genes in order to yield amplicons below 100 bp. TaqMan-based real-time PCR was adjusted to quantify each species separately. Cycle threshold (C(T)) values were calculated for each species according to the initial number of copies. A reliability analysis was carried out using intra-class correlation coefficients (ICCs) with a two-way random effects model. RESULTS: A high sensitivity and specificity was obtained for the detection of the three bacterial species. The TaqMan real-time PCR technology yielded a good repeatability in the obtained cycle threshold (C(T)) values for each initial number of copies, demonstrating coefficients of variation below 5% for each bacteria. The reproducibility of the technique was also demonstrated by the high ICCs (>0.98; p<0.00001) obtained for each bacteria with and without the addition of subgingival plaque. CONCLUSION: A novel diagnostic method based on TaqMan real-time PCR was developed for the quantification of Aa, Pg and Tf. It has demonstrated good sensitivity and repeatability on pure cultures. Its diagnostic utility should be demonstrated in subgingival plaque samples.     

Time-dependent recovery from the effects of 6-hydroxydopamine lesions of the rat nucleus accumbens on cocaine self-administration and the levels of dopamine in microdialysates

Rationale Neurotoxin induced lesions of dopamine-releasing neurons that innervate the nucleus accumbens (NAcc) alter cocaine self-administration. In addition, elevated extracellular levels of NAcc dopamine (DA) are thought to be central to the biological mechanisms that underlie this behavior.Objectives This study assessed the long-term effects of 6-hydroxydopamine (6-OHDA) induced lesions of the NAcc on cocaine self-administration and the dialysate levels of dopamine ([DA]_d) in this structure to determine if recovery of drug intake was correlated with the DA response.Methods Rats implanted with jugular catheters and bilateral cannulas were trained to self-administer cocaine and subsequently received bilateral intracranial micro-injections of 6-OHDA or vehicle into the NAcc. The levels of DA and cocaine were determined in microdialysates of the NAcc collected during experimental sessions 6–7, 14–16, 29–30, and 44–46 days post-treatment.Results The 6-OHDA induced lesions significantly reduced cocaine self-administration for 3 weeks while vehicle treatment had a moderate effect for the first several days. Cocaine-induced increases in NAcc [DA]_d did not return to sham/vehicle treated control levels for 6 weeks in the lesioned group and DA content in the NAcc was 46% of control at 44 days post-lesion.Conclusions Although dopaminergic lesions of the NAcc produced profound effects on cocaine self-administration, responding recovered to control levels before cocaine-induced increases in NAcc [DA]_d while content of DA in the NAcc did not recover. These data suggest that the plasticity of neuronal systems in the NAcc related to cocaine self-administration and their response following 6-OHDA lesions is more complex than restoration of DAergic tone.     

Clinical evaluation of a new collagen matrix (Mucograft® prototype) to enhance the width of keratinized tissue in patients with fixed prosthetic restorations: a randomized prospective clinical trial

Aim: The aim of this study was to test a new collagen matrix (CM) aimed to increase keratinized gingiva/mucosa when compared with the free connective tissue graft (CTG).
Material and Methods: This randomized longitudinal parallel controlled clinical trial studied 20 patients with at least one location with minimal keratinized tissue (1 mm).
Main Outcome Measure: The 6-month width of keratinized tissue. As secondary outcomes, the aesthetic outlook, the maintenance of periodontal health and the patient morbidity were assessed pre-operatively at 1, 3 and 6 months.
Results: At 6 months, the CTG attained a mean width of keratinized tissue of 2.6 (0.9) mm, while the CM was 2.5 (0.9) mm, these differences being insignificant. In both groups, there was a marked contraction (60% and 67%, respectively) although the periodontal parameters were not affected. The CM group had a significantly lower patient morbidity (pain and medication intake) as well as reduced surgery time.
Conclusions: These results prove that this new CM was as effective and predictable as the CTG for attaining a band of keratinized tissue, but its use was associated with a significantly lower patient morbidity.