Sources of occupational stress amongst dentistry academics

BACKGROUND

Dentistry professionals may experience significantly higher occupational stress than other health professionals and dentistry academics may have specific work content and context sources of stress.

AIMS

The aim of this study is to identify common sources of occupational stress, and how these are associated with wellbeing, in dentistry academics.

MATERIALS & METHODS

A cross-sectional online survey with staff in Dentistry departments in Australia and New Zealand. Assessment included 23 items from five general domains of occupational stress from the NIOSH-Generic Job Stress Questionnaire, a 23-item list of sources of stress and the 22-item Psychological General Well-Being Index. Analyses used descriptive statistics and multiple linear regression.

RESULTS

A total of 107 respondents (average age 50 ± 11.7 years, 56.8% men) completed the survey. Leading sources of occupational stress were job future, time pressure at work, work overload, and administration demands. A multiple linear regression model significantly predicted wellbeing, F(8,77) = 13.141, p = .000, adj.R²  = .53, but there were no significant associations for any of the specific sources of stress.

CONCLUSION

The combination of time pressure, workload and responsibility, job dissatisfaction, low social support, and uncertain job future was inversely associated with wellbeing amongst these dentistry academics. Future studies should consider the development and evaluation of interventions to address these concerns.

Does the change from conventional circular to linear stapling in proximal gastric bypass surgery affect long-term quality of life?

Objective

The continuous desire to improve bariatric surgery outcomes, and therefore patient satisfaction, leads to a constant search for new surgical approaches. Every change in a well-established protocol needs to undergo evaluation and its benefit for patients must be demonstrated. With respect to technical changes in bariatric surgery, long-term effects on quality of life have not yet been studied. We analyzed quality of life scores and clinical outcomes at a single bariatric center transitioning from circular to a linear bypass protocol.

Methods

Between June 2012 and March 2016, 235 patients were included in this retrospective study from a prospectively collected database. Two groups were compared. Group CBP included those patients treated with a circular stapling bypass protocol (n=117). This protocol was primarily used in 2012. Between 2013 and 2015 a transition period occurred. Thereafter, the linear stapling bypass protocol (Group LBP, n=118) was primarily utilized. Quality of life (QoL) was assessed with the Moorehead-Ardelt QoL score, which was gathered preoperatively, and at 1, 2, and 5 years after surgery.

Results

Quality of life scores improved significantly after intervention in both study groups. The most prominent improvement was seen within the first year after surgery. There were no statistically significant differences between the groups. During the first two years, quality of life score improvement occurred independently of achieved weight loss, whereas a correlation between QoL-improvement and reported weight loss was identified between 24 and 60 months postoperatively (r2 0.112, p<0.001). Further, complications had no impact on change in QoL scores.

Conclusion

Quality of life scores assessed by the Moorehead-Ardelt QoL questionnaire were, independent of operative technique and postoperative weight loss, significantly improved in the first two years after gastric bypass surgery. Thereafter, QoL scores showed lasting improvement in correlation with further weight loss.

An ileo-colic intussusception reaching down to the descending colon - A case report

Introduction and importance

Intussusception in healthy adults is rare and often associated with oncologic diseases. This case report presents a case of an ileo-colic intussusception reaching down to the descending colon in a healthy adult that required ileo-colic resection.

Case presentation

We present a case of a 78-year-old male patient with acute onset unspecific abdominal pain. The medical history was unremarkable. Preoperative radiologic assessments showed an invagination of the small intestine into the colon without any signs of polyps or tumours. An emergency laparotomy with resection of the affected intestine was performed. The pathologist described a 49 cm length of intussuscepted colon and an additional 7 cm intussusception of the terminal ileum. A circular area with multiple polyps extending over 8 cm in the colon could be identified. The microscopic findings showed a low-grade dysplasia within this area. Following surgery, the patient was discharged to rehabilitation after a ten-day hospitalization.

Clinical discussion

Intussusception in adults is rare and the clinical presentation includes unspecific symptoms making the diagnosis challenging. In 90% of the cases, a pathologic lesion is found (two-thirds are neoplasms). An intussusception involving the colon should be treated surgically without prior reduction due to the high incidence of a neoplasm and the risk for perforation and tumour dissemination.

Conclusion

In the literature, neoplastic disease represents the major cause for intussusception in adults. This report presents a rare case of an ileo-colic intussusception reaching down to the descending colon treated successfully with a subtotal colectomy.

•

Intussusception is a differential diagnosis in adults with abdominal pain.

•

In up to 90% of the cases, an underlying disease or condition can be identified.

•

Increasing incidental diagnosis due to better quality and availability of CT scan.

•

If the colon is involved, the best treatment is surgical without prior reduction.

Spatial Patterns in Hospital-Acquired Infections in Portugal (2014-2017)

BACKGROUND

Hospital-Acquired Infections (HAIs) represent the most frequent adverse event associated with healthcare delivery and result in prolonged hospital stays and deaths worldwide.

AIM

To analyze the spatial patterns of HAI incidence from 2014 to 2017 in Portugal.

METHODS

Data from the Portuguese Discharge Hospital Register were used. We selected episodes of patients with no infection on admission and with any of the following HAI diagnoses: catheter-related bloodstream infections, intestinal infections by Clostridium difficile, nosocomial pneumonia, surgical site infections, and urinary tract infections. We calculated age-standardized hospitalization rates (ASHR) by place of patient residence. We used empirical Bayes estimators to smooth the ASHR. The Moran Index and Local Index of Spatial Autocorrelation (LISA) were calculated to identify spatial clusters.

RESULTS

A total of 318,218 HAIs were registered, with men accounting for 49.8% cases. The median length of stay (LOS) was 9.0 days, and 15.7% of patients died during the hospitalization. The peak of HAIs (n = 81,690) occurred in 2015, representing 9.4% of the total hospital admissions. Substantial spatial inequalities were observed, with the center region presenting three times the ASHR of the north. A slight decrease in ASHR was observed after 2015. Pneumonia was the most frequent HAI in all age groups.

CONCLUSION

The incidence of HAI is not randomly distributed in the space; clusters of high risk in the central region were seen over the entire study period. These findings may be useful to support healthcare policymakers and to promote a revision of infection control policies, providing insights for improved implementation.

Effect of albumin, urea, lysozyme and mucin on the triboactivity of Ti6Al4V/zirconia pair used in dental implants

The titanium implant/zirconia abutment interface can suffer failure upon mechanical and biological issues, ultimately leading to the loss of the artificial tooth. The study of the effect of the organic compounds present in saliva on the tribological behavior of these systems is of utmost importance to understand the failure mechanisms and better mimic the in vivo conditions. The aim of the present work is to evaluate the effect of the addition of albumin, urea, lysozyme and mucin to artificial saliva, on the triboactivity of Ti6Al4V/zirconia pair commonly used in dental implants and then, compare the results with those obtained with human saliva. The solutions' viscosity was measured and the adsorption of the different biomolecules to both Ti6Al4V and zirconia was accessed. Tribological tests were performed using Ti6Al4V balls sliding on zirconia plates inside of a corrosion cell. Friction and wear coefficients were determined, and the open circuit potential (OCP) was monitored during the tests. Also, the wear mechanisms were identified. The presence of mucin in the artificial lubricant led to the lowest wear coefficients. The main wear mechanism was abrasion, independently of the used lubricant. Adhesive wear was observed for the systems without mucin. Tribocorrosion activity and wear coefficient were lower in the presence of mucin. None of the studied artificial lubricants mimicked the effect of human saliva (HS) on the tribological behavior of the studied pair since this lubricant led to the lowest friction coefficient and highest corrosion activity.

An exploratory study of perfectionism, professional factors and psychological well-being of dentistry academics

BACKGROUND

Well-being might be lower among dentistry professionals than other health professionals, and differ by personal, professional and sociodemographic factors. Few studies have considered dentistry academics who have different work roles and functions than clinicians. This exploratory study focused on well-being among dentistry academics and aimed to explore associations with perfectionism, professional factors and sociodemographics.

METHOD

An online survey was carried out with academic staff in Dentistry and Oral Health departments of nine Universities in Australia and New Zealand. Well-being was assessed using the 22-item Psychological General Well-Being Index, with a maximum score of 110 indicating good well-being. Perfectionism was assessed using the 8-item Short Almost Perfect Scale, with a maximum score of 56 and a higher score indicating perfectionism. Twenty items were used to assess professional and 7 items assessed sociodemographic factors. Associations were explored using correlation and multiple linear regression.

RESULTS

There was no significant bivariate association between perfectionism and well-being. Multiple linear regression indicated a significant association between hours of undergraduate teaching and psychological well-being, after adjustment for age, gender, income and overall health.

CONCLUSION

This exploratory study showed poor well-being among dentistry academics, particularly in those teaching undergraduate students for more than 6 h/week.

The Motivational Thought Frequency Scales for increased physical activity and reduced high-energy snacking

OBJECTIVES

The Motivational Thought Frequency (MTF) Scale has previously demonstrated a coherent four-factor internal structure (Intensity, Incentives Imagery, Self-Efficacy Imagery, Availability) in control of alcohol and effective self-management of diabetes. The current research tested the factorial structure and concurrent associations of versions of the MTF for increasing physical activity (MTF-PA) and reducing high-energy snacks (MTF-S).

DESIGN

Study 1 examined the internal structure of the MTF-PA and its concurrent relationship with retrospective reports of vigorous physical activity. Study 2 attempted to replicate these results, also testing the internal structure of the MTF-S and examining whether higher MTF-S scores were found in participants scoring more highly on a screening test for eating disorder.

METHODS

In Study 1, 626 participants completed the MTF-PA online and reported minutes of activity in the previous week. In Study 2, 313 participants undertook an online survey that also included the MTF-S and the Eating Attitudes Test (EAT-26).

RESULTS

The studies replicated acceptable fit for the four-factor structure on the MTF-PA and MTF-S. Significant associations of the MTF-PA with recent vigorous activity and of the MTF-S with EAT-26 scores were seen, although associations were stronger in Study 1.

CONCLUSIONS

Strong preliminary support for both the MTF-PA and MTF-S was obtained, although more data on their predictive validity are needed. Associations of the MTF-S with potential eating disorder illustrate that high scores may not always be beneficial to health maintenance.

Regional drinking water composition effects on hip fracture risk: a spatial analysis of nationwide hospital admissions in Portugal, from 2000 to 2010

Abstract Geographical variation on hip fractures (HF) may be related to the geographical variation of drinking water composition (DWC); minerals in drinking water may contribute to its fragility. We aim to investigate the effects of DWC on HF risk in Portugal (2000-2010). From National Hospital Discharge Register we selected admissions of patients aged ≥50 years, diagnosed with HF caused by low/moderate energy traumas. Water components and characteristics were selected at the municipality level. A spatial generalized additive model with a negative binomial distribution as a link function was used to estimate the association of HF with variations in DWC. There were 96,905HF (77.3% in women). The spatial pattern of HF risk was attenuated after being adjusted for water parameters. Results show an indirect association between calcium, magnesium, and iron and HF risk but no clear relation between aluminum, cadmium, fluoride, manganese, or color and HF risk. Regarding pH, the 6.7pH and 7pH interval seems to pose a lower risk. Different dose-response relationships were identified. The increase of calcium, magnesium, and iron values in DWC seems to reduce regional HF risk. Long-term exposure to water parameters, even within the regulatory limits, might increase the regional HF risk.

The influence of socioeconomic, biogeophysical and built environment on old-age survival in a Southern European city

Old-age survival is a good indicator of population health and regional development. We evaluated the spatial distribution of old-age survival across Porto neighbourhoods and its relation with physical (biogeophysical and built) and socioeconomic factors (deprivation). Smoothed survival rates and odds ratio (OR) were estimated using Bayesian spatial models. There were important geographical differentials in the chances of survival after 75 years of age. Socioeconomic deprivation strongly impacted old-age survival (Men: least deprived areas OR=1.31(1.05-1.63); Women OR=1.53(1.24-1.89)), explaining over 40% of the spatial variance. Walkability and biogeophysical environment were unrelated to old-age survival and also unrelated to socioeconomic deprivation, being fairly evenly distributed through the city.

Adaptation and Resistance to Diseases in Brazil of Putative Sources of Common Bean Resistance to White Mold

Common bean breeding programs for white mold (WM) resistance are in their initial stages in Brazil. Sources of partial resistance to WM are available abroad but their performance in Brazil is unknown. In two greenhouse (straw test) and three field experiments conducted in three districts in the state of Minas Gerais, Brazil, we evaluated a total of 23 lines with putative WM resistance with the objective to select lines with resistance to WM and other diseases associated with high yield potential. Two field-resistant local lines, two susceptible local cultivars, and two susceptible international lines were also included in the study. In the greenhouse, Cornell 605, A 195, and G122 were among the lines with the highest partial resistance to WM. In the field, these three lines were highly resistant to WM and had intermediate resistance or were resistant to anthracnose, angular leaf spot, rust, and Fusarium wilt. Cornell 605 and A 195 had high-yield potential but G122 yielded 47% less than the local lines under WM pressure. Our results suggest that Cornell 605 and A 195 are the most useful sources of resistance to WM for use in common bean breeding programs in Brazil.

[PIPAC--Pressurized intraperitoneal aerosol chemotherapy. A novel treatment for peritoneal carcinomatosis]

Peritoneal carcinomatosis remains a diagnostic challenge with sparse treatment options. The effect of systemic chemotherapy remains limited inside the peritoneum due to low penetration and a relative resistance of peritoneal nodules. Heated IntraPeritoneal Chemotherapy (HIPEC) improves survival in selected patients but entails a high incidence of complications. Pressurized IntraPeritoneal Aerosol Chemotherapy (PIPAC) allows to disperse the active agents inside the peritoneal cavity by laparoscopy. Distribution and tissue penetration of chemotherapy by PIPAC are superior to HIPEC and systemic chemotherapy despite of lower doses. Systemic side effects are uncommon and surgical trauma is limited. Histological and clinical response rates in platinum-resistant patients approach 70% and survival data appear to be favorable compared with standard therapy.

4-Methylcoumarins with cytotoxic activity against T24 and RT4 human bladder cancer cell lines

4-Methylcoumarins were synthesized by microwave-assisted synthesis via Pechmann condensation and their cytotoxic activity against human bladder cancer cell lines was investigated.

Tools for address georeferencing - limitations and opportunities every public health professional should be aware of

Various address georeferencing (AG) tools are currently available. But little is known about the quality of each tool. Using data from the EPIPorto cohort we compared the most commonly used AG tools in terms of positional error (PE) and subjects' misclassification according to census tract socioeconomic status (SES), a widely used variable in epidemiologic studies. Participants of the EPIPorto cohort (n = 2427) were georeferenced using Geographical Information Systems (GIS) and Google Earth (GE). One hundred were randomly selected and georeferenced using three additional tools: 1) cadastral maps (gold-standard); 2) Global Positioning Systems (GPS) and 3) Google Earth, single and in a batch. Mean PE and the proportion of misclassified individuals were compared. Google Earth showed lower PE than GIS, but 10% of the addresses were imprecisely positioned. Thirty-eight, 27, 16 and 14% of the participants were located in the wrong census tract by GIS, GPS, GE (batch) and GE (single), respectively (p<0.001). Misclassification according to SES was less frequent but still non-negligible −14.4, 8.1, 4.2 and 2% (p<0.001). The quality of georeferencing differed substantially between AG tools. GE seems to be the best tool, but only if prudently used. Epidemiologic studies using spatial data should start including information on the quality and accuracy of their georeferencing tools and spatial datasets.

Transitional and freshwater bioassessments: one site, two perspectives?

The freshwater-saltwater-transition-zone was analysed using two different sampling protocols and assessment methodologies, developed for freshwater and estuaries, to compare their agreement level in terms of community composition and quality assessments. The use of different protocols resulted in significant differences in macroinvertebrate communities, in index scores and initially in quality classes. After modifications in the sensitivity scores of the IBMWP and AMBI indices (average scores or the use of a score of the other index when both were present), the differences were largely reduced and quality classes became coincident for the assessments provided by IPtIs and BAT tools. Such harmonisation of quality assessments for adjacent water categories (e.g., large rivers vs. transitional waters), exemplified here as an harmonisation in one of the metrics comprised in the assessment tools, is essential as it has direct implications on the expansion and accomplishment of River Basin Management Plans committed by the Water Framework Directive.

White Mold Management in Common Bean by Increasing Within-Row Distance Between Plants

White mold of common bean (Phaseolus vulgaris), caused by Sclerotinia sclerotiorum, is a major yield-limiting disease during the fall-winter season in Brazil. This study was conducted to evaluate the efficacy of decreasing within-row densities for an indeterminate growth habit (type IIIa) cultivar, keeping constant the between-row spacing of 0.5 m, to manage the disease. A modification of within-row plant distributions was also attempted in order to reduce white mold intensity. The study was conducted with sprinkler irrigation in two growing seasons (2000 and 2001) in Viçosa, State of Minas Gerais, Brazil, in an area naturally infested with sclerotia. In 2000, treatments were arranged as 3 × 2 × 2 factorial combination of within-row densities (15, 7.5, or 5 plants/m), within-row plant distributions (single and equidistant plants or equidistant groups of three plants), and fluazinam treatments (with or without). In 2001, 16, 12, 8, or 4 plants/m were combined with fluazinam treatments. Fluazinam was applied at both flowering onset and 10 or 13 days later. Average incidence was 92.6% in 2000 and 77.8% in 2001; severity index was 69.8% in 2000 and 40.2% in 2001; and yield was 1,656 kg/ha in 2000 and 2,542 kg/ha in 2001. White mold decreased and yield increased as within-row densities were reduced, regardless of fluazinam treatments. A distribution of equidistant groups of three plants was ineffective in reducing disease. The use of 4 equidistant plants/m in infested irrigated areas was an effective strategy in white mold management.

Opportunistic macroalgae metrics for transitional waters. Testing tools to assess ecological quality status in Portugal

Macroalgae communities constitute one of the ecological quality elements for the evaluation of the ecological quality status (EQS) of coastal and transitional waters, required to implement the WFD. While these algae are natural components of estuarine systems and play important roles in several estuarine processes, macroalgal blooms are of ecological concern because they can reduce the habitat quality. Several works are being carried out to set standard methods for monitoring macroalgae blooms, in order to develop tools to derive EQS based upon this biological quality element. The aim of this paper is to apply the methodology described by Scanlan et al. [Scanlan, C.M., Foden, J., Wells, E., Best, M.A., 2007. The monitoring of opportunistic macroalgal blooms for the water framework directive. Marine Pollution Bulletin 55, 162-171] to a series of data assembled in the south arm of the Mondego estuary (Atlantic coast of Portugal) considering two different ecological situations. Additionally, an alternative assessment method intended to be used when no biomass data are available was also tested. In general, both options captured the inter-annual variations in accordance with the system evolution. Option 2, less expensive and time-consuming, allowed an EQS evaluation with accurate results when biomass data were not available. The results suggest that sampling should be carried out from April to June.

Development and validation of a LC method for determination of genistein in topical nanoemulsions

The aim of this study was to develop and validate an isocratic LC method for the quantification of genistein in topical nanoemulsions. The analyses were performed at room temperature on a reversed-phase C18 column using a mobile phase composed of methanol/water/acetonitrile (70:25:5, w/w/w) at 1.0 ml x min(-1). The detection was carried out on a UV detector at 327 nm. The linearity, in the range of 25-75 microg/ml, presented a determination coefficient (r2) higher than 0.999, calculated by the least square method. No interferences from the excipients (egg-lecithin, octyldodecanol or medium chain triglycerides) were detected. The R.S.D. values for intra- and inter-day precision experiments were lower than 2.3%. The recovery of genistein from nanoemulsions ranged from 96.6% to 106.6%. The excellent performance of the method, its linearity, accuracy and precision, demonstrate that it can be readily used to quantify genistein incorporated in nanoemulsions.

A systematic review of the quality of homeopathic pathogenetic trials published from 1945 to 1995

BACKGROUND

The quality of information gathered from homeopathic pathogenetic trials (HPTs), also known as 'provings', is fundamental to homeopathy. We systematically reviewed HPTs published in six languages (English, German, Spanish, French, Portuguese and Dutch) from 1945 to 1995, to assess their quality in terms of the validity of the information they provide.

METHODS

The literature was comprehensively searched, only published reports of HPTs were included. Information was extracted by two reviewers per trial using a form with 87 items. Information on: medicines, volunteers, ethical aspects, blinding, randomization, use of placebo, adverse effects, assessments, presentation of data and number of claimed findings were recorded. Methodological quality was assessed by an index including indicators of internal and external validity, personal judgement and comments of reviewers for each study.

RESULTS

156 HPTs on 143 medicines, involving 2815 volunteers, produced 20,538 pathogenetic effects (median 6.5 per volunteer). There was wide variation in methods and results. Sample size (median 15, range 1-103) and trial duration (mean 34 days) were very variable. Most studies had design flaws, particularly absence of proper randomization, blinding, placebo control and criteria for analysis of outcomes. Mean methodological score was 5.6 (range 4-16). More symptoms were reported from HPTs of poor quality than from better ones. In 56% of trials volunteers took placebo. Pathogenetic effects were claimed in 98% of publications. On average about 84% of volunteers receiving active treatment developed symptoms. The quality of reports was in general poor, and much important information was not available.

CONCLUSIONS

The HPTs were generally of low methodological quality. There is a high incidence of pathogenetic effects in publications and volunteers but this could be attributable to design flaws. Homeopathic medicines, tested in HPTs, appear safe. The central question of whether homeopathic medicines in high dilutions can provoke effects in healthy volunteers has not yet been definitively answered, because of methodological weaknesses of the reports. Improvement of the method and reporting of results of HPTs are required.

REFERENCES

References to all included RCTs are available on-line at.

Evaluation of the antiherpetic activity of standardized extracts of Achyrocline satureioides

Traditionally, Achyrocline satureioides or 'marcela' has been used in South America for the treatment of several disorders. For the present study, three spray-dried extracts (N1, N2 and N3) were used, all of them prepared with 50% of an hydroethanolic extract rich in flavonoid compounds and 50% of blends of different adjuvants. The cytotoxic concentration which causes destruction in 50% monolayer cells (CC50) was 62.5 microg/ml for the three extracts. The antiviral activity was evaluated by using two different strains of herpes simplex virus (HSV-1) and the best results were obtained with KOS strain and N2 extract. Studies concerning the mechanism of the antiherpetic activity demonstrated that N2 extracts showed no virucidal effect or activity on cellular receptors. HSV-1 DNA synthesis was not inhibited. The antiherpetic activity occurred between the second and ninth hour of the virus replication cycle, probably indicating a perturbation on late stages of this cycle.

Cationic emulsions improves the delivery of oligonucleotides to leukemic P388/ADR cells in ascite

The aim of this study was to investigate the in vivo ability of O/W cationic emulsions to deliver oligonucleotides (ON) in leukemic P388/ADR cells in ascite, after intraperitoneal (IP) administration in mice. Cationic emulsions were prepared by microfluidization as previously described by Teixeira et al. [Pharm. Res 16 (1999) 30]. The formulations consisted mainly of medium chain triglycerides, phosphatidylcholine (PC), poloxamer, and either a monocationic lipid stearylamine (PC/SA-emulsion) or a polycationic lipid RPRC(18) (PC/RPRC(18)-emulsion). A model ON (33P-pdT(16)) was associated with cationic emulsions by single addition at the end of the manufacturing process. Seven days after P388/ADR inoculation IP to mice, ON free or associated with PC/SA or PC/RPRC(18) emulsions was injected IP at a dose of 0.5 mg/kg. At different interval times, ascite including cells, blood and the main organs were collected and the radioactivity counted by liquid scintillation. The overall results showed significantly high amounts of ON in the leukemic cell pellet, 24 h after administration of ON associated to either PC/SA (AUC(0-24 h)=13634, %injected dose/min) or PC/RPRC(18) (AUC(0-24 h)=22592, % injected dose/min), contrary to the free ON solution (AUC(0-24 h)=3095, %injected dose/min), which displayed only reduced capture by cancer cells. In conclusion, complexation of ON with cationic emulsions had a beneficial effect in increasing tumor cells uptake in vivo (up to sevenfold for PC/RPRC(18)-emulsion) after IP administration. This could open interesting prospects for the treatment of ovarian cancers.

A fatal forensic intoxication with fenarimol: analysis by HPLC/DAD/MSD

Fenarimol (Rubigan) is a pyrimidine ergosterol biosynthesis inhibitor used as a systemic fungicide. The authors present a fatal fenarimol intoxication case analysed in the Forensic Toxicology Service of the National Institute of Legal Medicine. The results were used to compare two different HPLC techniques, regarding selectivity and sensitivity: an HPLC system with a diode array detector (DAD) and an HPLC system with a DAD and a mass spectrometry detector (MSD) with an electrospray interface. All biological samples were submitted to a solid-phase extraction procedure. The detection and quantification limits of fenarimol, linearity, precision and accuracy were evaluated. The fenarimol concentration levels determined were of 89.0 mg/ml in gastric contents, 1.9 mg/g in liver and 0.4 mg/g in kidney. Blood was not available at autopsy. No published data related to fenarimol self-poisoning were found, so it was not possible to interpret the results obtained by comparison with toxic/lethal levels.

Lactobacillic acid accumulation in the plasma membrane of Oenococcus oeni: a response to ethanol stress?

It is known that ethanol strongly interferes with the development and activity of lactic acid bacteria in wine. In this work, it was observed that membrane composition was dependent of ethanol concentration and cell physiological state. The protein electrophoretic profile was modified in the membranes of Oenococcus oeni cultured in presence of 8 and 10% ethanol. Concerning the membrane lipid composition, it was observed that O. oeni maintained a high level of phospholipid biosynthesis via the relative increased biosynthesis of phosphoethanolamine and sphingomyelin in presence of ethanol. On the other hand, ethanol induced an increase in the membrane lactobacillic acid percentage at the expense of cis-vaccenic acid. This increased synthesis of lactobacillic acid appears as the more significant change induced by ethanol in O. oeni membrane. The increase of lactobacillic acid in the membrane of O. oeni clearly appears as a factor that provides protection against the toxic effect of ethanol, balancing the increase of membrane fluidity normally attributed to ethanol. The results presented in this paper constitute evidence that lactobacillic acid may have a part in the survival and or adaptive mechanisms developed by O. oeni under culture adverse conditions, allowing these bacteria to maintain their activity in the presence of ethanol, namely performing malolactic fermentation in wine.

Characterization of oligonucleotide/lipid interactions in submicron cationic emulsions: influence of the cationic lipid structure and the presence of PEG-lipids

We have recently described how oligonucleotide (ON) stability and release from O/W cationic emulsions are governed by the lipid composition. The aim of the present paper was to investigate the properties of the ON/lipid complexes through fluorescence resonance energy transfer (FRET), size, surface tension measurements and cryomicroscopy. Starting from a typical emulsion containing stearylamine as a cationic lipid, the influence of the lipid structure (monocationic molecules bearing mono or diacyl chains, or polycations) as well as of the presence of PEGylated lipids, were studied. The presence of a positive charge on the droplet surface clearly contributed to enhance the ON interaction with lipid monolayers and to bring the ON molecules closer to the interface. Hydrophobic interactions through the acyl chains were shown to further enhance the anchorage of the ON/lipid complexes. In contrast, the incorporation of PEGylated lipids acted as a barrier against the establishment of electrostatic bindings, the polyethyleneglycol chains acting themselves as interaction sites for the ON leading to hydrophilic complexes. Similar features were observed for the polycationic lipid, and cryomicroscopy revealed the existence of bridges of various intensities between the droplets of the emulsion containing either PEG or the polycation, probably because of the configuration of the ON at the interface.

Factors influencing the oligonucleotides release from O-W submicron cationic emulsions

We recently described a positively charged O-W emulsion as a delivery system for oligonucleotides (ON) [Teixeira et al., Pharm. Res. 16 (1999) 30-36]. The present paper investigates the role of the main formulation parameters that may have an influence on the release-rate of a model ON in a protein-containing medium, i.e. the nature of the oily core, the presence of pegylated lipids, the lipid phase transition temperature, and the cationic lipid structure. The use of cationic lipids bearing diacyl chains (and especially polycations) appeared as the only efficient strategy to reduce the ON release rate. In order to have a better insight on the nature of the interactions between the ON and the interfacial lipids, adsorption isotherms at the air-water interface, fluorescence resonance energy transfer and zeta-potential measurements have been performed. Electrostatic interactions were found to play a crucial role. In contrast, the incorporation of PEG-phospholipids acted as a barrier and maintained the ON molecules distant from the interface, leading to a more rapid release. Finally, ON integrity was assessed by a competitive hybridization assay. The results suggest the existence of a transient ion-pair (ON-cationic lipids) protecting ON against nuclease degradation even after its release from the emulsions.

Submicron cationic emulsions as a new delivery system for oligonucleotides

PURPOSE

The main purpose of the present study was to investigate submicron emulsions as potential oligonucleotide (ON) delivery system.

METHODS

Submicron emulsions containing various concentrations of stearylamine (SA) were prepared by microfluidization. After association with model oligothymidylates, these emulsions were characterized in terms of particle size, zeta-potential, association efficiency and release upon dilution. The interactions between ON and SA were investigated by partitioning studies between water and oily phases, with ON of three different lengths (pdT16, pdT30, pdT50). The stability of pdT16 in the presence of nucleases was evaluated by incubation in cell culture medium supplemented with 10% of foetal calf serum.

RESULTS

The ON association efficiency was much higher with emulsions containing SA (E(SA)) than with control emulsions (E0), whatever the ON length. In addition, E(SA) was shown to protect ON against degradation for up to 3 hours in culture medium. ON and SA were able to form ion-pairs and the resulting complex was found to be insoluble both in water and in oil. Zeta potential was maintained constant when increasing the ON concentration, until flocculation occurred (up to 250 microM in the case of pdT16 for example). This has been explained by the presence of SA in excess, soluble in the oily core of droplets, able to migrate towards the interface and replacing SA neutralized in ion-pairs.

CONCLUSIONS

ESA appears to be a valuable system for delivery of ON and might even be improved by selecting an oily phase in which the SA/ON complex would be soluble.

[Aneurysms of the interatrial septum]

Atrial septum aneurysms are an uncommon condition, underestimated before the routine use of echocardiography. Their clinical importance has increased after being associated with thromboembolic events. The authors made a review of clinical, diagnostic and therapeutic features of this entity after reporting six clinical cases.

[Risk factors for cerebrovascular stroke in a cohort of hypertensive patients]

OBJECTIVES

To identify stroke risk factors in hypertensive patients and the probability of stroke in relation to those risk factors and follow-up.

STUDY DESIGN

A cohort study (patients with high blood pressure).

MATERIAL AND METHODS

707 hypertensive patients were studied (Hypertension Register) in what concerns stroke incidence until 1992 (n = 126), considering one case per individual. The following variables were analysed: age, sex, body mass index (Quetelet), systolic and diastolic blood pressure, heart rate, types of hypertension (JNC-IV), left ventricular hypertrophy, changes in ST segment and T wave (Minnesota Code), fundi, angina pectoris, heart failure, central nervous (neurological) disturbances, antihypertensive treatment, smoking, serum potassium, serum sodium, blood urea, creatinine, uric acid, blood sugar, diabetes and cholesterol, in the initial record. Individually, in relation to the control of hypertension, the subjects were classified according to the casual recording of normal blood pressure, the absence of drug treatment, diastolic pressure > 114 mmHg and, at the end of 1992, according to survival, causes of death and follow-up. Stroke risk factors have been identified by multivariate analysis (Cox regression model). The survival probability (without stroke) was defined by Kaplan-Meier method.

RESULTS

It was possible to maintain the epidemiological surveillance, from 1975 to 1992, of 598 cases. From those, 109 hypertensive patients were victims of at least one episode of non transient cerebral ischaemia, during their follow-up of 10.5 years. From the characteristics studied, only five were identified at risk factors. The adjusted relative risks and confidence intervals (95% CI) were the following: age: 1.08 (1.06-1.10); diastolic pressure > 114 mmHg: 1.96 (1.32-2.91); neurological disturbances 4.64 (2.99-7.2); diabetes: 2.57 (1.62-4.05) and left ventricular hypertrophy: 1.34 (1.13-1.58).

CONCLUSIONS

As far as stroke is concerned: a) Age, diabetes, a casual measurement of diastolic blood pressure > 114 mmHg and left ventricular hypertrophy (electrocardiogram) were the risk factors identified; b) Prevention should include blood pressure and diabetes control, although this disease has shown more risk than a casual measurement of severe hypertension; c) Its occurrence, in this model, has only partly been explained, therefore it has become necessary to deepen the study of the risk profile.

[Cardiac metastases from a colonic tumor]

Antemortem diagnosis of cardiac metastasis is rarely observed. A case of cardiac metastasis from colon adenocarcinoma is reported. The diagnosis of an intracavitary mass of the right atrium and vegetant mass of the tricuspid valve was possible by two dimensional transthoracic echocardiography. The authors make a brief reference to the clinical and imaging features of secondary cardiac tumors, with special emphasis on echocardiography.

[Cerebellar hematomas in a patient with atrial myxoma]

We describe a case report of a 69 year old woman with atrial myxoma, presented as a cerebellar syndrome caused by ischemic infarctions of the posterior circulation. The transthoracic 2D echocardiogram provided the diagnosis of a left atrial myxoma. Seven months after surgical removal of the cardiac tumor, the cerebellar syndrome worse with the acute development of intracranial hypertension. A CT scan detected multiple hematomas of both lobes and vermix of the cerebellum and hydrocephalus. These late neurologic complications permitted us to suspect and discuss some diagnostic hypotheses. Cardiac myxomas are rare and their presentation as early neurologic manifestations occur in 20-25% of the cases. The late neurologic complications of myxoma are even more rare, only a few cases being reported in world literature.