Antimicrobial activity of two techniques for arm skin disinfection of blood donors in Brazil

Objective: Evaluation of the antimicrobial effect of skin disinfection techniques is essential to avoid the transmission of infectious agents during blood transfusion. The aim of this study was to examine the effectiveness of two methods of arm skin disinfection used in blood donors at a Hemotherapy Center in Brazil that represents an important centre for distributing haemocomponents to many cities in the country. Methods: Two skin disinfection techniques in 50 blood donors were evaluated. For the first arm, 10% povidone-iodine/two-stage technique was used. On the opposite arm, 0.5% chlorhexidine digluconate alcohol solution/one-stage technique was used. The swabs were seeded on three culture media: blood agar, mannitol salt agar and Mac Conkey agar. Automated bacterial classification based on biochemical tests/specific substrates was performed. Donor characteristics were collected using the computerised system of the Hemotherapy Center. Results: We found that microbial reduction was significantly higher for 10% povidone-iodine technique (98.57-98.87%) when compared with 0.5% chlorhexidine technique (94.38-95.06%). The species Leuconostoc mesenteroides and Staphylococcus hominis showed resistance to both disinfection techniques. We did not find statistically significant relationships between donor characteristics and microbial reduction. Conclusions: Arm skin disinfection with 10% povidone-iodine produced better antimicrobial activity. We must acknowledge that 10% povidone-iodine technique has the limitation of being a two-stage method. However, prevention of adverse events due to bacterial contamination and transfusion reactions should be prioritised. Production of hypoallergenic and stronger antiseptics that allowed a safe one-stage disinfection technique should be encouraged in health systems, not only in Brazil but also around the world.

Topical Treatment Using Amphotericin B and DMSO for an Atypically Located Equine Cutaneous Pythiosis

Background: Cutaneous lesions by Pythium insidiosum infection are commonly observed in horses, especially in those living at flooded environments. Equine pythiosis is characterized by the development of tumoral masses that are frequently located at distal limbs, ventral abdomen, thorax, breast and face. The lesions are usually granulomatous, serosanguineous and ulcerated, most often destroyed by self-mutilation due to the intense pruritus. The proposed treatment includes surgical excision followed by antifungal drugs administration, which can be done systemically or topically. Amphotericin B and dimethyl sulfoxide (DMSO) in association has been successfully used for cutaneous pythiosis topical treatment due to the DMSO property to carry any substance through plasmatic membranes. Case: The present report concerns a 12-year-old mixed breed gelding presenting with self-mutilation of a tumoral mass located at the left flank. The owners reported that the horse had initially presented a small wound that had evolved to a 20-cm in diameter mass in 4 weeks. Tissue samples were collected, processed and stained by the Gomori's methenamine silver (GMS) method. The histopathological analysis revealed Pythium insidiosum hyphae in a granulomatous tissue, especially located at peripheral region, where kunkers were present. Surgical excision of the mass followed by cauterization was indicated as initial treatment, and due to financial reasons, the owners elected only the topical antifungal therapy to control the fungus infection after surgery. Flunixin meglumine was also administrated for five days aiming the control of pain and inflammation. The wound was cleaned with povidone-iodine solution and rinsed with a solution containing, 50 mg, of amphotericin B in 10 mL of sterile water and 10 mL of DMSO. This procedure was carried Out twice a day. The wound healed fast due to an excellent centripetal epithelialization. and the horse was discharged after 64 days showing only 5% of the initial wound area. The owner reported by telephone the complete healing and hair growth 10 days after discharge. Discussion: Despite the atypical location of the tumoral lesion described at the present report, the history and clinical manifestations, especially the intense pruritus, showed similarity with other characteristic reports of equine cutaneous pythiosis. The diagnosis was confirmed by the histopathological examination showing hyphae structures, as described to be evidences of the presence of Pythium insidiosum in the tissue. The surgical procedure was the first step to provide remission of clinical signs, and one day after surgery the pruritus desapeared. After excision of the granulomatous tissue and cauterization, daily topical administration of amphotericin B associated with DMSO was effective in destroying the infectious agent, as observed by the excellent epithelization. A pink granulation tissue grew up providing an ideal surface for epithelial migration and the healing process progressed quickly. Centripetal epithelialization reduced the wound area until 3% of the initial area in 64 days of treatment, when the remaining wound was found almost completely healed and covered with hair. At the present report, the horse presenting pythiosis was only topically treated. The recommended therapy using amphotericin B and DMSO solution was effective, economically viable and low risk, considering that the systemic antifungal therapy usually suggested is expensive and extremely nephrotoxic. The atypical location of the lesion on the left flank shows that any anatomical region can be affected by the fungus, since the conditions for its development were present.

Burrow ventilation and associated porewater irrigation by the polychaete Marenzelleria viridis

Burrow ventilation of benthic infauna generates water currents that irrigate the interstices of the sediments surrounding the burrow walls. Such activities have associated effects on biogeochemical processes affecting ultimately important ecosystem processes. In this study, the ventilation and irrigation behavior of Marenzelleria viridis, an invasive polychaete species in Europe, was analyzed using different approaches. M. viridis showed to perform two types of ventilation: (1) muscular pumping of water out of the burrow and (2) cilia pumping of water into the burrow. Flowmeter measurements presented muscular pumping in time averaged rates of 0.15 ml min(-1). Oxygen needle electrodes positioned above the burrow openings revealed that muscular undulation of the worm body pumps anoxic water out of the burrow. On the other hand, microscope observations of the animal showed that ventilation of oxygen-rich water in the burrow occurs by ciliary action. The volume of water irrigated by M. viridis appears to vary linearly within the first 24 h incubation, with rates ranging from 0.003 to 0.01 ml min(-1). From those rates we could estimate that the time averaged rate of cilia ventilation should be about 0.16 ml min(-1). Since the cilia pumping into the burrow occurs in periods of 24 +/- 12 min and at 50-70% of the measured time, considerable amounts of water from deeper sediments may percolate upwards to the sediment surface. This water is rich in reduced compounds and nutrients and may have important associated ecological implications in the ecosystem (e.g. affecting redox conditions, organic matter degradation, benthic recruitment and primary production). (C) 2010 Elsevier B.V. All rights reserved.

Effects of irrigation on water use and water use efficiency in two fast growing Eucalyptus plantations

Eucalyptus plantations occupy almost 20 million ha worldwide and exceed 3.7 million ha in Brazil alone. Improved genetics and silviculture have led to as much as a three-fold increase in productivity in Eucalyptus plantations in Brazil and the large land area occupied by these highly productive ecosystems raises concern over their effect on local water supplies. As part of the Brazil Potential Productivity Project, we measured water use of Eucalyptus grandis x urophylla clones in rainfed and irrigated stands in two plantations differing in productivity. The Aracruz (lower productivity) site is located in the state of Espirito Santo and the Veracel (higher productivity) site in Bahia state. At each plantation, we measured stand water use using homemade sap flow sensors and a calibration curve using the clones and probes we utilized in the study. We also quantified changes in growth, leaf area and water use efficiency (the amount of wood produced per unit of water transpired). Measurements were conducted for 1 year during 2005 at Aracruz and from August through December 2005 at Veracel. Transpiration at both sites was high compared to other studies but annual estimates at Aracruz for the rainfed treatment compared well with a process model calibrated for the Aracruz site (within 10%). Annual water use at Aracruz was 1394 mm in rainfed treatments versus 1779 mm in irrigated treatments and accounted for approximately 67% and 58% of annual precipitation and irrigation inputs respectively. Increased water use in the irrigated stands at Aracruz was associated with higher sapwood area, leaf area index and transpiration per unit leaf area but there was no difference in the response of canopy conductance with air saturation deficit between treatments. Water use efficiency at the Aracruz site was also not influenced by irrigation and was similar to the rainfed treatment. During the period of overlapping measurements, the response to irrigation treatments at the more productive Veracel site was similar to Aracruz. Stand water use at the Veracel site totaled 975 mm and 1102 mm in rainfed and irrigated treatments during the 5-month measurement period respectively. Irrigated stands at Veracel also had higher leaf area with no difference in the response of canopy conductance with air saturation deficit between treatments. Water use efficiency was also unaffected by irrigation at Veracel. Results from this and other studies suggest that improved resource availability does not negatively impact water use efficiency but increased productivity of these plantations is associated with higher water use and should be given consideration during plantation management decision making processes aimed at increasing productivity. Published by Elsevier B.V.

Subsurface drip irrigation: Conventional dripper and new prototype

Subsurface drip irrigation that uses an emitter protection system to avoid its clogging by roots and soil particles may be viable compared to a conventional system. The objective of this work was to evaluate the performance of a system with emitter protection, and to compare the results with a system that uses a conventional emitter for subsurface drip irrigation. In the system with protection an inexpensive materials polyethylene hose, microtube, connector, and a dripper to control the flow rate were used; and, in the conventional system a commercial emitter was used. After 12 months of evaluation, the system with protector showed good performance, with relative average flow rate of 0.97 and 0.98 in pots with and without crop, respectively, showing no clogging problems and lower cost. In conventional system relative flow rate of 0.51 and 0.98 were observed in pots with and without crop, respectively, also clogging degree by roots of 49.22%, and emitters with soil inside was observed. Thus, the use of emitter with protection presented feasibility for subsurface drip irrigation, under conditions used in this research.

Turing patterns in the chlorine dioxide-iodine-malonic acid reaction with square spatial periodic forcing

We use the photosensitive chlorine dioxide-iodine-malonic acid reaction-diffusion system to study wavenumber locking of Turing patterns to two-dimensional "square" spatial forcing, implemented as orthogonal sets of bright bands projected onto the reaction medium. Various resonant structures emerge in a broad range of forcing wavelengths and amplitudes, including square lattices and superlattices, one-dimensional stripe patterns and oblique rectangular patterns. Numerical simulations using a model that incorporates additive two-dimensional spatially periodic forcing reproduce well the experimental observations.

Nutrients and Nonessential Elements in Soil after 11 Years of Wastewater Irrigation

Irrigation of citrus (Citrus aurantium L. x Citrus paradise Macf.) with urban reclaimed wastewater (RWW) can be economical and conserve fresh water. However, concerns remain regarding its deleterious effects on soil quality. We investigated the ionic speciation (ISP) of RWW and potential impacts of 11 yr of irrigation with RWW on soil quality, compared with well-water (WW) irrigation. Most of nutrients (similar to 53-99%) in RWW are free ionic species and readily available for plant uptake, such as: NH4+, NO3-, K+, Ca2+, Mg2+, SO42-, H3BO3, Cl-, Fe2+, Mn2+, Zn2+, Co2+, and Ni2+, whereas more than about 80% of Cu, Cr, Pb, and Al are complexed with CO3-, OH-, and/or organic matter. The RWW irrigation increased the availability and total concentrations of nutrients and nonessential elements, and soil salinity and sodicity by two to three times compared with WW-irrigated soils. Although RWW irrigation changed many soil parameters, no difference in citrus yield was observed. The risk of negative impacts from RWW irrigation on soil quality appears to be minimal because of: (i) adequate quality of RWW, according to USEPA limits; (ii) low concentrations of metals in soil after 11 yr of irrigation with RWW; and (iii) rapid leaching of salts in RWW-irrigated soil during the rainy season.

Excessive iodine intake in schoolchildren

Inadequate iodine intake may result in iodine deficiency disorders (IDD). Thus, for more than 50 years, policies for the regulation of salt fortification with iodine have existed in Brazil. In 2003, a study on 6-14-year-old schoolchildren from regions of the state of So Paulo showed a median urinary iodine concentration of 360 mu g/L. The objective of the present study was to assess the iodine nutrition status among schoolchildren. The study was conducted on 828 schoolchildren aged 4-13 years from eight schools in the interior of the state of So Paulo. A casual urine sample was collected from each volunteer for iodine determination by the adapted method of Sandell-Kalthoff. Only 1.9% (n = 16) of the children evaluated had low values of urinary iodine (< 100 mu g/L), while 24.6% had urinary iodine excretion values between 200 and 300 mu g/L, and 67.1% had values above > 300 mu g/L. The results show that the iodine nutritional status of the schoolchildren studied is characterized by a high urinary iodine excretion, which might reveal an increase in iodine consumption by this population.

Yield of two castor bean cultivars under different depths of supplemental irrigation

This study evaluated the yield, components of production and oil content of two castor bean cultivars through drip irrigation with different water depths. The research was conducted in 2009 in an Oxisol clay in the experimental field in Dourados, Mato Grosso do Sul State. The experimental design was randomized blocks in factorial scheme with five water depths (0, 25, 50, 100 and 150% of evapotranspiration for drip irrigation) in two castor bean cultivars (IAC 2028 and IAC 80) with four replications. The irrigation schedule was predetermined up to two irrigations per week except on rainy days. The increase of irrigation provided significant increase in most components of production and crop yield without changing the oil content of seeds. The application of higher water depth increased yield by 80% in relation to the treatment that received no supplemental irrigation.

Biochemical control of prostate cancer with iodine-125 brachytherapy alone: experience from a single institution

Brachytherapy is an adequate option as monotherapy for localised prostate cancer. The objective of this study was to evaluate and compare biochemical failure free survival (BFFS) after low-dose-rate brachytherapy (LDRB) alone for patients with prostate cancer using ASTRO and Phoenix criteria, and detect prognostic factors. Data on 220 patients treated between 1998 and 2002 with LDRB were retrospectively analysed. Neoadjuvant hormone therapy was used in 74 (33.6%) patients. Median follow-up was 53.5 months (24-116). Five year BFFS was 83.0% and 83.7% using, respectively, the ASTRO and Phoenix criteria. Low -and intermediate-risk patients presented, respectively, 86.7% and 77.8% 5-year BFFS using the ASTRO definition (p=0.069), and 88.5% and 78.6% considering the Phoenix criteria (p=0.016). Bounce was observed in 66 (30%) patients. Multivariate analysis detected PSA at diagnosis < 10 ng/ml and less than 50% positive biopsy fragments as favourable prognostic factors, regarding BF using both criteria. For the Phoenix criteria, also Gleason score < 7 and low-risk group were identified as independent favourable prognostic factors. LDRB alone should be considered mostly for low-risk patients. PSA level was a strong independent prognostic factor. We support the use of the Phoenix criteria for detection of BF in patients submitted to LDRB alone.

Synthesis of Chromanes and 4H-Chromenes: Exploring the Oxidation of 2H-Chromenes and Dihydro-1-benzoxepines by Hypervalent Iodine(III)

The reaction of various oxygen-containing benzo-fused cycloalkenes were studied with the hypervalent iodine reagent hydroxy(tosyloxy) iodo]benzene [PhI(OH)OTs, HTIB]. 2H-Chromene and 4-methyl-2H-chromene resulted in substituted 4H-chromene and cis-3,4-dialkoxy-4-methyl-3,4-dihydro-2H-chromenes, respectively. Ring contraction to chromanes and benzofurans was observed for dihydrobenzoxepines and 2,2-dimethyl-2H-chromenes, respectively.

Effect of passive ultrassonic instrumentation as a final irrigation protocol on debris and smear layer removal

This study sought to evaluate the efficacy of passive ultrasonic irrigation (PUI) on removing the smear layer and debris from root dentin using scanning electron microscopy (SEM). Twenty-five bovine incisors were manually prepared and divided into three groups according to the final irrigation protocol: EDTA, final irrigation with 12 mL of 17% EDTA for 3 minutes followed by 5 mL of 2.5% NaOCl; EDTA=PUI, final flush with 4 mL of 17% EDTA and PUI for 30 seconds. These procedures were repeated three times to standardize the volume of the irrigant. Control group, after preparation, the specimens were irrigated only with 17 mL of 2.5% NaOCl. The roots were fractured and analyzed using SEM. The intragroup analysis revealed that the EDTA=PUI protocol removed a higher amount of debris at the cervical third (P 5 0.03). The intergroup analysis revealed that EDTA=PUI presented the lowest amount of debris at the cervical third (P 5 0.007). Smear layer scores were higher in the control group compared with the EDTA and EDTA=PUI groups, but only at the cervical third (P 50.02). None of the final irrigant protocols completely removed the smear layer and debris. EDTA=PUI only improved the removal of debris at the cervical third.

Optimizing endodontic irrigation: advantages of negative apical pressure technology

FAPESP #2010/16002-4

The antimicrobial effect of new and conventional endodontic irrigants on intra-orally infected dentin

Objectives. To evaluate if the incorporation of antimicrobial compounds to chelating agents or the use of chelating agents with antimicrobial activity as 7% maleic acid and peracetic acid show similar disinfection ability in comparison to conventional irrigants as sodium hypochlorite or iodine potassium iodide against biofilms developed on dentin. Materials and methods. The total bio-volume of live cells, the ratio of live cells and the substratum coverage of dentin infected intra-orally and treated with the irrigant solutions: MTAD, Qmix, Smear Clear, 7% maleic acid, 2% iodine potassium iodide, 4% peracetic acid, 2.5% and 5.25% sodium hypochlorite was measured by using confocal microscopy and the live/dead technique. Five samples were used for each irrigant solution. Results. Several endodontic irrigants containing antimicrobials as clorhexidine (Qmix), cetrimide (Smear Clear), maleic acid, iodine compounds or antibiotics (MTAD) lacked an effective antibiofilm activity when the dentin was infected intra-orally. The irrigant solutions 4% peracetic acid and 2.5–5.25% sodium hypochlorite decrease significantly the number of live bacteria in biofilms, providing also cleaner dentin surfaces (p < 0.05). Conclusions. Several chelating agents containing antimicrobials could not remove nor kill significantly biofilms developed on intra-orally infected dentin, with the exception of sodium hypochlorite and 4% peracetic acid. Dissolution ability is mandatory for an appropriate eradication of biofilms attached to dentin.

Economic viability of retrofiting emitters in center pivot irrigation systems

Although several studies have been conducted to evaluate the uniformity of water application under center pivot irrigation systems, there are few studies concerning the economic perspective of such coefficient. The aim of this study is to present a methodology to accomplish an economic analysis as support for the decision-making to retrofit emitters in center pivot irrigation systems, and to attribute an economic meaning to the uniformity coefficient of water application taking into account the response function productivity to the amount of water applied and the sale price of the crops. In the hypothetic calculation example considering the variation of revenue of potato crop under center pivot irrigation system, it was verified that the area with uniformity coefficient of water application of 90% brought an income increase of BR$ 1,992.00, considering an area about 1,0 ha. Thus, it can be concluded that the methodology presented has met the objectives proposed in the study and made it possible to attribute an economical meaning to the coefficient of water uniformity application.