Removal of Positively Buoyant Planktothrix rubescens in Lake Restoration

The combination of a low-dose coagulant (polyaluminium chloride—‘Floc’) and a ballast able to bind phosphate (lanthanum modified bentonite, LMB—‘Sink/Lock’) have been used successfully to manage cyanobacterial blooms and eutrophication. In a recent ‘Floc and Lock’ intervention in Lake de Kuil (the Netherlands), cyanobacterial chlorophyll-a was reduced by 90% but, surprisingly, after one week elevated cyanobacterial concentrations were observed again that faded away during following weeks. Hence, to better understand why and how to avoid an increase in cyanobacterial concentration, experiments with collected cyanobacteria from Lakes De Kuil and Rauwbraken were performed. We showed that the Planktothrix rubescens from Lake de Kuil could initially be precipitated using a coagulant and ballast but, after one day, most of the filaments resurfaced again, even using a higher ballast dose. By contrast, the P. rubescens from Lake Rauwbraken remained precipitated after the Floc and Sink/Lock treatment. We highlight the need to test selected measures for each lake as the same technique with similar species (P. rubescens) yielded different results. Moreover, we show that damaging the cells first with hydrogen peroxide before adding the coagulant and ballast (a ‘Kill, Floc and Lock/Sink’ approach) could be promising to keep P. rubescens precipitated.     

Pharmacy and therapeutics committees strategy to address olmesartan safety issues at a primary care level

International Journal of Clinical Pharmacy - Background Olmesartan, an antihypertensive drug, has been associated with a severe and potentially life-threatening sprue-like enteropathy, consisting...     

Substituted adenine quartets: interplay between substituent effect,hydrogen bonding,and aromaticity

Adenine, one of the components of DNA/RNA helices, has the ability to form self-organizing structures with cyclic hydrogen bonds (A₄), similar to guanine quartets. Here, we report a computational investigation of the effect of substituents (X = NO₂, Cl, F, H, Me, and NH₂) on the electronic structure of 9H-adenine and its quartets (A₄-N1, A₄-N3, and A₄-N7). DFT calculations were used to show the relationships between the electronic nature of the substituents, strength of H-bonds in the quartets, and aromaticity of five- and six-membered rings of adenine. We demonstrated how the remote substituent X modifies the proton-donating properties of the NH₂ group involved in the H-bonds within quartets and how the position of the substituent and its electronic nature affect the stability of the quartets. We also showed the possible changes in electronic properties of the substituent and aromaticity of adenine rings caused by tetramer formation. The results indicate that the observed relationships depend on the A₄ type. Moreover, the same substituent can both strengthen and weaken intermolecular interactions, depending on the substitution position.

Substituent effects on hydrogen bonds in adenine quartets and aromaticity of adenine rings depend on the quartet type. A₄-N3 and A₄-N7 quartets are more responsive to the electronic nature of substituents than A₄-N1.     

Efficacy and safety of twice-daily aclidinium bromide in COPD patients: the ATTAIN study

The efficacy and safety of two doses of aclidinium bromide were evaluated in patients with moderate to severe chronic obstructive pulmonary disease (COPD). In this 24-week, double-blind trial, patients were randomised to twice-daily aclidinium (200 μg or 400 μg) or placebo. The primary efficacy end-point was change in trough forced expiratory volume in 1 s (FEV(1)) at week 24. Other end-points included peak FEV(1), health status (St George's Respiratory Questionnaire; SGRQ) and dyspnoea (Transitional Dyspnoea Index; TDI). Overall, 828 patients were randomised. At week 24, significant improvements from baseline were observed with aclidinium 200 μg and 400 μg versus placebo for trough FEV(1) (99 and 128 mL; both p<0.0001) and peak FEV(1) (185 and 209 mL; both p<0.0001). Peak FEV(1) improvements on day 1 were comparable with week 24. Aclidinium 200 μg and 400 μg produced significant improvements over placebo in baseline-adjusted mean SGRQ total score (-3.8 and -4.6 units; p<0.001 and p<0.0001) and TDI focal score (0.6 and 1.0 units; p<0.05 and p<0.001) at week 24. With both aclidinium doses, the incidence of anticholinergic adverse events was low, and similar to placebo. Twice-daily aclidinium significantly improved bronchodilation, health status and dyspnoea, and was well tolerated in patients with COPD.     

Postmortem Characterization of Patients With Clinical Diagnosis of Plasmodium vivax Malaria: To What Extent Does This Parasite Kill?

Background.?Severe disease attributable to Plasmodium vivax infection is already well described worldwide; however, autopsies in these patients are scarce. Methods.?From 1996 to 2010, 19 patient deaths with a clinical diagnosis of P. vivax infection occurred in a tertiary care center in the Brazilian Amazon. Seventeen of these 19 deaths were fully autopsied. Clinical charts, macroscopic autopsy reports, and stored paraffinized tissue blocks were retrieved. Nested polymerase chain reaction was performed in paraffinized samples of spleen and lung to confirm P. vivax monoinfection. Immunohistofluorescence was used to detect P. vivax parasitized red blood cells (RBCs). Results.?Of 17 autopsies, 13 revealed that death could be attributed to P. vivax infection; in the remaining 4, acute diseases other than malaria were found to be the cause of death. The primary complication in patients in which malaria contributed to death was acute respiratory distress syndrome (ARDS) and pulmonary edema associated with the accumulation of neutrophils in the interalveolar space (6 cases). Spleen rupture (3 cases) and multiorgan dysfunction syndrome (3 cases) were the second most common complications. One child evolving with coma was also characterized, but no parasite was detected in the brain tissue. In one patient who developed ARDS and presented negative peripheral parasitemia by the time of death, scattered parasitized red blood cells were seen inside pulmonary capillaries, suggesting some sequestration in the lung. Conclusions.?In 13 of 17 deceased patients, P. vivax infection was the plausible cause of death. However, more studies are needed to understand pathogenesis related to severe disease.     

In vitro and in vivo repeatability of abdominal diffusion-weighted MRI

Objective

To study the in vitro and in vivo (abdomen) variability of apparent diffusion coefficient (ADC) measurements at 1.5 T using a free-breathing multislice diffusion-weighted (DW) MRI sequence.

Methods

DW MRI images were obtained using a multislice spin-echo echo-planar imaging sequence with b-values=0, 100, 200, 500, 750 and 1000 s mm⁻². A flood-field phantom was imaged at regular intervals over 100 days, and 10 times on the same day on 2 occasions. 10 healthy volunteers were imaged on two separate occasions. Mono-exponential ADC maps were fitted excluding b=0. Paired analysis was carried out on the liver, spleen, kidney and gallbladder using multiple regions of interest (ROIs) and volumes of interest (VOIs).

Results

The in vitro coefficient of variation was 1.3% over 100 days, and 0.5% and 1.0% for both the daily experiments. In vivo, there was no statistical difference in the group mean ADC value between visits for any organ. Using ROIs, the coefficient of reproducibility was 20.0% for the kidney, 21.0% for the gallbladder, 24.7% for the liver and 28.0% for the spleen. For VOIs, values fall to 7.7%, 6.4%, 8.6% and 9.6%, respectively.

Conclusion

Good in vitro repeatability of ADC measurements provided a sound basis for in vivo measurement. In vivo variability is higher and when considering single measurements in the abdomen as a whole, only changes in ADC value greater than 23.1% would be statistically significant using a two-dimensional ROI. This value is substantially lower (7.9%) if large three-dimensional VOIs are considered.Diffusion-weighted (DW) MRI is based on the Brownian motion of water in biological tissues [1,2]. The technique has played a preponderant role in neuro-imaging over the last two decades and it is known to detect small changes before they are apparent on anatomical imaging [3,4].In recent years DW MRI has been increasingly used in other parts of the body, demonstrating great diagnostic potential in cancer imaging. To date, DW MRI has been successfully used for tissue characterisation and tumour staging. However, the apparent diffusion coefficient (ADC) is a potential biomarker that could be used to monitor treatment response or evaluate post-therapeutic changes. Details of the clinical use of DW MRI can be found in the 2009 consensus paper [5] or in general and organ-specific review articles [6-8].While DW MRI is a potentially powerful tool in diagnostic oncology, the lack of uniform protocols for imaging and data analysis hinder its clinical implementation. Large differences in ADC values are reported in the literature depending on the acquisition parameters, in particular the choice of b-values (e.g. see [9] for ADC values in the kidney or 5] highlighted the importance of quality analysis, validation and reproducibility studies. Although there are some emerging reproducibility and repeatability data in the abdomen [15,19-22], a recent review by Taouli and Koh [7] highlights the need for further work in this area. Recently, coefficients of variability of around 14% were published for both solid tumours [22] and bone marrow [23]. Other studies seem to indicate that only ADC changes of over 27% [20] or 30% [21] are significant. Substantial variations in ADC values have also been found between different scanners and vendors [24-26], further highlighting the difficulty of setting up multicentre trials.

Table 1

Apparent diffusion coefficient values measured in normal liver at 1.5 T

Light and electron microscopic immunocytochemical visualization of 5-HT1B receptors in the rat brain

Specific antipeptide antibodies were used for the immunohistochemical visualization of 5-HT_1B receptors in the rat brain. A dense, specific 5-HT_1B receptor-like immunoreactivity was found in the globus pallidus, the dorsal subiculum and the substantia nigra. At the light microscope level, immunostaining was diffuse within the neuropil but absent from cell bodies. Observations at the electron microscope level in the substantia nigra showed immunoperoxidase staining in fine unmyelinated axons and nerve terminals.     

Proposal for revision of the European Laryngological Society classification of endoscopic cordectomies

A classification of laryngeal endoscopic cordectomies, which included eight different types, was first proposed by the European Laryngological Society in 2000. The purpose of this proposal of classification was an attempt to reach better consensus amongst clinicians and agree on uniformity in reporting the extent and depth of resection of cordectomy procedures, to allow relevant comparisons within the literature when presenting/publishing the results of surgery, and to recommend the use of guidelines to allow for reproducibility amongst practicing laryngologists. A total of 24 article citations of this classification have been found through the science citation index, as well as 3 book chapters on larynx cancer surgery, confirming its acceptance. However, on reflection, and with the passage of time, lesions originating at the anterior commissure have not been clearly described and, for that reason, a new endoscopic cordectomy (type VI) for cancers of the anterior commissure, which have extended or not to one or both of the vocal folds, without infiltration of the thyroid cartilage is now being proposed by the European Laryngological Society Committee on Nomenclature to revise and complete the initially reported classification.     

Declining hepatitis A seroprevalence in adults in Catalonia (Spain): a population-based study

Background  

One of the main uses of seroprevalence studies it to evaluate vaccination programmes. In 1998, a programme of universal vaccination of preadolescents in schools with the hepatitis A vaccine was begun in Catalonia. The objective of this study was to investigate the prevalence and risk factors of hepatitis A virus infection (HAV) in a sample of the adult population of Catalonia in 2002 and to evaluate the changes with respect to a survey carried out in 1996.