Ethanol Disinfection Research Articles

Influence of Seed Disinfection Treatments on the Germination Rate and Histamine-Degrading Activity of Legume Sprouts

Edible legume sprouts have been proposed as a promising plant-based source of the enzyme diamine oxidase (DAO), which plays a key role in degrading histamine at an intestinal level and preventing the development of histamine intolerance symptoms. However, the temperature and humidity conditions required for seed germination can also favor the rapid growth of yeast and mold, potentially compromising sprout yield and quality. The aim of this study was to evaluate the influence of different seed disinfection treatments on both the germination rate and DAO enzymatic activity in sprouts of four Leguminosae species. Seed disinfection with 70% ethanol for either 5 or 15 min slightly increased the germination rates of chickpea and soybean sprouts without affecting DAO activity, regardless of treatment duration. However, in lentil and green pea sprouts, ethanol disinfection caused a statistically significant reduction in histamine-degrading capacity. In contrast, treating seeds with sodium hypochlorite for 15 min increased germination rates by up to 14% and preserved DAO activity in all legume sprouts tested. These results indicate that incorporating a seed disinfection step during legume sprouting may affect both the DAO enzymatic activity and germination rate.

Glove decontamination procedures to prevent pathogen and DNA cross-contamination among frogs.

Working with aquatic organisms often requires handling multiple individuals in a single session, potentially resulting in cross-contamination by live pathogens or DNA. Most researchers address this problem by disposing of gloves between animals. However, this generates excessive waste and may be impractical for processing very slippery animals that might be easier to handle with cotton gloves. We tested methods to decontaminate cotton or nitrile gloves after contamination with cultured Batrachochytrium dendrobatidis (Bd) or after handling heavily Bd-infected Xenopus laevis with layered cotton and nitrile gloves. Bleach eliminated detectable Bd DNA from culture-contaminated nitrile gloves, but gloves retained detectable Bd DNA following ethanol disinfection. After handling a Bd-infected frog, Bd DNA contamination was greatly reduced by removal of the outer cotton glove, after which either bleach decontamination or ethanol decontamination followed by drying hands with a paper towel lowered Bd DNA below the detection threshold of our assay. These results provide new options to prevent pathogen or DNA cross-contamination, especially when handling slippery aquatic organisms. However, tradeoffs should be considered when selecting an animal handling procedure, such as the potential for cotton gloves to abrade amphibian skin or disrupt skin mucus. Disposing of gloves between animals should remain the gold standard for maintaining biosecurity in sensitive situations.

Exploring the key deteriorative microorganisms on ancient ivories unearthed from the Sanxingdui Ruins site during temporary cold storage.

The ancient ivories unearthed from the Sanxingdui Ruins site are valuable cultural relics, however, the microbial biodeterioration on ivories during temporary cold storage poses a great threat to their later long-term preservation. Here, the combination of high-throughput sequencing and biochemical assays was applied for the in-depth investigation of the key deteriorative microorganisms colonizing on the ivories and the tracing of their origin, as well as the assessment of the ethanol disinfection impact on the microbial communities on ivories. It was observed that the surfaces of ivories were scattered by the fungal patches of white, dark grey, and hedge green colors during cold storage. The high-throughput sequencing results showed that the genera Mortierella (38.51%), Ilyonectria (14.43%), Penicillium (1.15%), and Aspergillus (1.09%) were the dominant fungi, while Pseudomonas (22.63%), Sphingopyxis (3.06%), and Perlucidibaca (2.92%) were the dominant bacteria on ivories. The isolated Aspergillus A-2 resulted in the highest amount of calcium releasing from the degradation of hydroxyapatite (HAP), the main component of ivory, by the organic acids produced, including oxalic acid and citric acid. The fast expectation-maximization for microbial source tracking (FEAST) analysis revealed that the majority of the fungi (57.45%) and bacteria (71.84%) colonizing on the ivories were derived from the soils surrounding ivories in the sacrifice pits, indicating soils as the primary source for the spoilage microbes growing on ivories. The dominant strains could degrade cellulose, the key components of wet cotton towels commonly applied on ivories for moisture maintenance, aiding the spoilage microbes colonizing on ivories. Notably, the ivory disinfection with 75% ethanol during the cleansing significantly decreased the relative abundance of the dominant genera of Ilyonectria, Aspergillus, and Pseudomonas, with Mortierella becoming the dominant one on ivories. Together, the fungi, particularly Aspergillus and Penicillium, played a significant role in the microbial biodeterioration of unearthed ancient ivories by producing the organic acids. These results may improve the control of the microbial biodeterioration and develop more efficient strategies for the long-time conservation of unearthed ancient ivories and other cultural relics.

Umbilical Granuloma: Frequency, Associated Factors, 10-Year Treatment Trends, and Effectiveness at a Single Hospital in Japan.

Umbilical granuloma (UG) is a common problem during the neonatal period; however, its epidemiology and etiology are poorly studied, and the best treatment option has not yet been established. We examined the medical records of neonates who were born and underwent 1-month evaluations at our hospital between 2013 and 2022 to investigate the frequency of-and factors associated with-UG, as well as the annual trends of UG treatments and their efficacy. Of the 6680 eligible neonates, 395 (5.9%) had UG. The annual incidence rate ranged from 3.8% to 7.3%. Gestational age, birth weight, and incidence of meconium-stained amniotic fluid were significantly associated with UG. Silver nitrate cauterization was the predominant UG treatment from 2013 to 2016. Silver nitrate cauterization and topical betamethasone valerate were nearly equally applied in 2017. Betamethasone application became predominant in 2018. The healing rates during the initial treatment period were 91% for silver nitrate cauterization, 97.7% for betamethasone application, 60% for ethanol disinfection, and 88% for ligation; these rates were significantly different (p < 0.001). Topical steroid application may be the most effective treatment. If steroid application is ineffective, then silver nitrate cauterization and ligation may be important treatment options.

Effect of short-term in vitro antibiotic administration into the human umbilical cord tissue on cfu count and mesenchymal stem cell immunophenotype

Mesenchymal stem cells play important roles in regenerative and reparative medicine applications. Their differentiation and proliferation abilities both in the human body and in the laboratory, environment have been revealed through many clinical and pre-clinical trials. Umbilical cord tissue is an important source of mesenchymal stem cells and has become a popular option in cord blood banking, especially in the last decade. As done for the cord blood, the steps of obtaining, transferring, processing, and cryopreserving umbilical cord tissue are defined by standard procedures. However, there is limited information about the microbiological contamination rate of tissues and their decontamination before the procedure. This study aimed to assess the effect of in vitro short-term antibiotic treatment applied to the umbilical cord tissue obtained via superficial ethanol disinfection immediately after birth on the formation of colony-forming units (CFUs) and immunophenotype of the mesenchymal stem cells. For this purpose, tissues obtained from 10 individuals were evaluated in three different groups that included the control group and groups of tissues with 5- and 10-min antibiotic treatment. There was no significant difference among the groups in the expression levels of CD45, CD34, CD73, CD105, and CD44, which are the markers used in immunophenotyping. Similarly, no difference was found in CFU formation either. The present study has revealed for the first time that an antibiotic preparation used in in vitro cell culture for cord tissue banking can be used safely in tissue preparation and banking stages. Our results show that short-term in vitro antibiotic administration can contribute to the standard formation during decontamination/disinfection stages in cord tissue banking.

The spread of SARS-CoV-2 in Spain: Hygiene habits, sociodemographic profile, mobility patterns and comorbidities

COVID-19 constitutes the largest pandemic in the last 100 years. In view of the rapid spread of the virus, it is necessary to study the sociodemographic characteristics, hygiene habits, activity and mobility, and comorbidities of SARS-CoV-2 infection to be able to implement prevention strategies. For this purpose, a survey including the variables of interest was designed to try to understand the exponential spread of the virus despite the implemented severe restrictive mobility measures during the period of maximum confinement in Spain. This study conducted throughout the Spanish territory aims to clarify other routes of transmission of the COVID-19 during confinement, risk factors, and the effectiveness of the recommended hygiene measures to detect critical points of exposure to the virus and thus reduce its spread in this and possible future pandemics that could compromise public health.Our results show that living with a COVID-19 patient increased the risk of contagion by 60 times. Among all the sociodemographic variables analyzed, walking the dog have shown to have the strongest effect by increasing the risk by 78%. The most effective hygiene measure reducing the prevalence of the disease was the disinfection of products purchased from the market upon arrival home (which reduced the risk by 94%), above other hygiene measures, such as wearing masks, gloves, ethanol disinfection, bleaching and others. The mobility variable studied that showed the largest increase in the prevalence of the disease was working on site at the workplace (increased the risk by 76%). A significant higher prevalence of the disease was also detected among respondents who used the modality of acquiring basic commodities using home delivery service compared to those who chose in-store shopping.

Alcohol pretreatment of stools effect on culturomics

Recent studies have used ethanol stool disinfection as a mean of promoting valuable species’ cultivation in bacteriotherapy trials for Clostridium difficile infections (CDI) treatment with a particular focus on sporulating bacteria. Moreover, the culturomic approach has considerably enriched the repertoire of cultivable organisms in the human gut in recent years. This study aimed to apply this culturomic approach on fecal donor samples treated with ethanol disinfection to evidence potential beneficial microbes that could be used in bacteriotherapy trials for the treatment of CDI. Thereby, a total of 254 bacterial species were identified, 9 of which were novel. Of these, 242 have never been included in clinical trials for the treatment of CDIs, representing potential new candidates for bacteriotherapy trials. While non-sporulating species were nevertheless more affected by the ethanol pretreatment than sporulating species, the ethanol disinfection technique did not specifically select bacteria able to sporulate, as suggested by previous studies. Furthermore, some bacteria previously considered as potential candidates for bacteriotherapy have been lost after ethanol treatment. This study, while enriching the bacterial repertoire of the human intestine, would nevertheless require determining the exact contribution of each of species composing the bacterial consortia intended to be administered for CDI treatment.

Situations Leading to Reduced Effectiveness of Current Hand Hygiene against Infectious Mucus from Influenza Virus-Infected Patients.

Both antiseptic hand rubbing (AHR) using ethanol-based disinfectants (EBDs) and antiseptic hand washing (AHW) are important means of infection control to prevent seasonal influenza A virus (IAV) outbreaks. However, previous reports suggest a reduced efficacy of ethanol disinfection against pathogens in mucus. We aimed to elucidate the situations and mechanisms underlying the reduced efficacy of EBDs against IAV in infectious mucus. We evaluated IAV inactivation and ethanol concentration change using IAV-infected patients' mucus (sputum). Additionally, AHR and AHW effectiveness against infectious mucus adhering to the hands and fingers was evaluated in 10 volunteers. Our clinical study showed that EBD effectiveness against IAV in mucus was extremely reduced compared to IAV in saline. IAV in mucus remained active despite 120 s of AHR; however, IAV in saline was completely inactivated within 30 s. Due to the low rate of diffusion/convection because of the physical properties of mucus as a hydrogel, the time required for the ethanol concentration to reach an IAV inactivation level and thus for EBDs to completely inactivate IAV was approximately eight times longer in mucus than in saline. On the other hand, AHR inactivated IAV in mucus within 30 s when the mucus dried completely because the hydrogel characteristics were lost. Additionally, AHW rapidly inactivated IAV. Until infectious mucus has completely dried, infectious IAV can remain on the hands and fingers, even after appropriate AHR using EBD, thereby increasing the risk of IAV transmission. We clarified the ineffectiveness of EBD use against IAV in infectious mucus.IMPORTANCE Antiseptic hand rubbing (AHR) and antiseptic hand washing (AHW) are important to prevent the spread of influenza A virus (IAV). This study elucidated the situations/mechanisms underlying the reduced efficacy of AHR against infectious mucus derived from IAV-infected individuals and indicated the weaknesses of the current hand hygiene regimens. Due to the low rate of diffusion/convection because of the physical properties of mucus as a hydrogel, the efficacy of AHR using ethanol-based disinfectant against mucus is greatly reduced until infectious mucus adhering to the hands/fingers has completely dried. If there is insufficient time before treating the next patient (i.e., if the infectious mucus is not completely dry), medical staff should be aware that effectiveness of AHR is reduced. Since AHW is effective against both dry and nondry infectious mucus, AHW should be adopted to compensate for these weaknesses of AHR.

Differences in Disinfection Protocols of Raw Material Vials Intended for the Production of Parenteral Nutrition Mixtures

AbstractBackgroundPreparation of parenteral nutrition (PN) mixtures is performed in a controlled atmosphere area (CAA) under a laminar flow hood. In 2014 and 2015 quality controls have revealed contaminations of PN bags by Bacillus. The different products used to avoid this contamination were Aniosurf premiumMethodsFive protocols have been tested by varying the disinfection step: hydrogen peroxide (H2O2) or sodium hypochlorite (immersion or spray), ethanol (non sporicidal) only by immersion. Prewash and aerosolization steps remained unchanged. For each series, a quantity of 30 vials have been prewashed, then disinfected according to the tested protocol, and finally aerosolized. In order to quantify the effectiveness of disinfection 10 vials were sampled using contact plates at every step of treatment.ResultsMicroorganisms were found after ethanol disinfection (n=4) and aerosolization (n=2). No germs were found when hydrogen peroxide or sodium hypochlorite were used. The atmospheric rates of H2O2 were 0.2 ppm by immersion and 0.8 ppm by spray, these values are below the recommended value level (1 ppm).ConclusionsThis study has validated the use and effectiveness of these disinfecting products. Taking into account the efficiency and ease of use for staff, immersion has been preferred to spray and hydrogen peroxide to sodium hypochlorite.

Effects of Cultivar and Ethanol Disinfection on Aseptic Germination of Loquat (Eriobotrya japonica) Seeds

Loquat (Eriobotrya japonica Lindl.) is an economically important subtropical fruit tree, originating and commercially produced mainly in China and Japan. The aseptic seed germination of 13 loquat cultivars, including 9 white-fleshed cultivars and 4 red-fleshed ones, was studied, and the relationship between the germination rate and the content of endogenous ABA in seeds was explored. The germination rate and the seedling height at 80 days after sowing of white-fleshed cultivars were generally higher than that of red-fleshed ones. The ABA content in seeds was generally lower in white-fleshed cultivars, and the ABA content negatively correlated with the germination rate at 80 days after sowing. A moderate detrimental effect of 75% ethanol disinfection on aseptic germination of loquat seeds was observed, especially, for the cultivar Dahongpao, and the germination rate and seedling height were reduced by around half and one-third, respectively. The addition of plant preservative mixture (PPM) to the germination medium at a final concentration of 25 mg·L−1 effectively controlled contamination when the 75% ethanol disinfection procedure was omitted.

Preliminary Investigation and Characterization of Electrospun Polycaprolactone and Manuka Honey Scaffolds for Dermal Repair

This study focused on the characterization of Manuka honey-containing poly(ε-caprolactone) (PCL) nanofiber scaffolds with regards to wound healing. Scaffolds were electrospun from 1, 5, 10, and 20% v/v Manuka honey solutions. Scaffolds were subjected to ethanol disinfection and soaked in phosphate-buffered saline (PBS) for various timepoints, and scaffold morphology and honey release was quantified. Scaffolds showed increased water vapor transmission rate (WVTR) with scaffold soak time, indicating an increase in evaporation due to enhanced osmotic potential of the scaffolds. Mechanical testing indicated lower elasticity and strength with honey incorporation, but showed no significant change in material degradation rate with the presence of honey over a 28 day PBS soak. Fibroblast studies showed honey incorporation increased cell infiltration into the scaffold, but scaffold conditioned media did not induce significant chemotaxis towards the scaffold. Honey incorporation also demonstrated an increase in fibroblast proliferation when in direct contact with the scaffolds. Bacterial clearance from pure honey was observed in both Gram positive Streptococcus agalactiae (Group B Streptocococcus) and Gram negative Escherichia coli ( E. coli), but honey scaffolds demonstrated significant clearance in only the Gram negative E. coli. While further investigation is needed, this preliminary study demonstrates the wound-healing potential of Manuka honey-loaded electrospun scaffolds.

A microbiological evaluation of level of disinfection for flexible cystoscopes protected by disposable endosheaths

BackgroundFlexible cystoscopy is used in urological outpatient departments for diagnostic cystoscopy of bladder cancer and requires a high-level disinfection between each patient. The purpose of this study was to make a microbiological post disinfection efficacy assessment of flexible cystoscopes (FC) using disposable sterile endosheaths.MethodsOne hundred endosheaths underwent a leak-test for barrier integrity after cystoscopy. Microbiological samples from these cystoscopies were obtained; after removal of the endosheath, and after cleaning the scope with a detergent cloth, rinsing with tap water followed by 70% ethanol disinfection and subsequent drying. The number of colony forming units (cfu) from the samples was counted after 72 hours and then divided in three categories, Clean FC (<5 cfu/sample), Critical FC (5–50 cfu/sample) and High-risk FC (>50 cfu/sample). The result was compared with data of 10 years continuous control sampling recorded in the Copenhagen Clean-Endoscope Quality Control Database (CCQCD) and analyzed with a Chi-square test for homogeneity.ResultsAll 100 endosheaths passed the leak-test. All samples showed a Clean FC and low means of cfu. A query to the CCQCD, showed that 99.8% (1264/1267) of all FC with a built-in work-channel reprocessed in a WD were clean before use.ConclusionThe reprocessing of FC using endosheaths, as preformed in this study, provides a patient-ready procedure. The results display a reprocessing procedure with low risk of pathogen transmission, high patient safety and a valid alternative to the recommended high-level disinfection procedure of FC. However, the general impression was that sheaths slightly reduced vision and resulted in some patient discomfort.

The microbial colonization profile of respiratory devices and the significance of the role of disinfection: a blinded study.

Approximately 10-40% of all the nosocomial infections are pulmonary, which lead to grave complications. Elderly, debilitated, or critically ill patients are at a high risk. The respiratory care equipments which include ventilators, humidifiers, nebulizers may have been identified as the potential vehicles which cause major nosocomial infections if they are colonized by fungi or bacteria. To determine the rate of colonization by bacteria and fungi of the oxygen humidifier chambers of the portable cylinders and central lines at our hospital. The Hudson's chambers of nebulizers were also studied for the same. Swab samples were obtained from the equipments by using sterile cotton swabs on a tuesday, as these chambers were usually cleaned on every Saturday. Spot samples were taken from the ICUs, wards, the casualty and OPDs on a single day. Air samples were also obtained on the same day to determine whether the fungal spore load in the inhaled room air was normal or high. We performed a disinfection with 70% ethanol after cleaning these devices. 53/70 (75.71%) samples showed fungal growth; out of which, 23/33 (69.70%) were from the ICU, 24/30(80%) were from the wards and 6/7 (85.71%) were from the OPDs. 23/30 (76.66%) swabs from the central line humidifiers, 18/23(78.26%) swabs from the O2 cylinder humidifiers and 8/17 (47.5%) swabs from the nebulizers grew bacteria. Of the total 61(87.14%) bacterial isolates, 42(68.85%) were gram negative bacteria and 19(31.14%) were gram positive cocci. Out of the 42 gram negative bacteria, 17 were multi-drug resistant like ESBL producers ie. Pseudomonas spp. (6) Acinetobacter spp.(4), Klebseilla pneumoniae (4), E.coli (2) and Stenotrophomonas maltophila (1). Our findings (before disinfection) showed that the colonization rate for fungi was 75% and that for bacteria, it was 87%. After the 70% ethanol disinfection and strict compliance with the hand hygiene, the colonization rates reduced significantly. The fungal colonization rate was reduced and only 15% fungi grew after the disinfection, while only 12% bacterial colonization rate was found. This study indicates a potential in-hospital source of allergens and infections. The oxygen and nebulizer chambers need to be cleaned more frequently with disinfectants, to control the possible nosocomial infections.

Ethanol disinfection affects physical properties and cell response of electrospun poly(l-lactic acid) scaffolds

Disinfection of electrospun materials is commonly carried out by ethanol (EtOH) soaking. However, in the literature no systematic investigation on the effect of EtOH disinfection on scaffold properties is available. In this study electrospun poly(l-lactic acid) (PLLA) scaffolds were differently treated in EtOH and changes of fiber morphology, fiber surface topography and scaffold thermo-mechanical properties were evaluated. It was found that EtOH induced the formation of an amount of crystal phase, in the initially amorphous fibers, which depends on EtOH grade, soaking time and temperature. Completely amorphous PLLA (a-PLLA) and semicrystalline PLLA (sc-PLLA) scaffolds were produced by applying different EtOH treatments to as-spun PLLA scaffold. Compared to a-PLLA, sc-PLLA was stiffer and composed of fibers with rougher surface. Cell culture performed by using permanent cell line H9c2 demonstrated that changes of scaffold properties determined a different cell response, in particular in the expression of proteins correlated to cell motility and cell adhesion.

Contact-Free Inactivation of Candida albicans Biofilms by Cold Atmospheric Air Plasma

Candida albicans is one of the main species able to form a biofilm on almost any surface, causing both skin and superficial mucosal infections. The worldwide increase in antifungal resistance has led to a decrease in the efficacy of standard therapies, prolonging treatment time and increasing health care costs. Therefore, the aim of this work was to demonstrate the applicability of atmospheric plasma at room temperature for inactivating C. albicans growing in biofilms without thermally damaging heat-sensitive materials. This so-called cold atmospheric plasma is produced by applying high voltage to accelerate electrons, which ionize the surrounding air, leading to the production of charged particles, reactive species, and photons. A newly developed plasma device was used, which exhibits a large plasma-generating surface area of 9 by 13 cm (117 cm(2)). Different time points were selected to achieve an optimum inactivation efficacy range of ≥3 log(10) to 5 log(10) reduction in CFU per milliliter, and the results were compared with those of 70% ethanol. The results obtained show that contact-free antifungal inactivation of Candida biofilms by cold atmospheric plasma is a promising tool for disinfection of surfaces (and items) in both health care settings and the food industry, where ethanol disinfection should be avoided.

Microbiologic assessment of disposable sterile endoscopic sheaths to replace high-level disinfection in reprocessing: A prospective clinical trial with nasopharygoscopes

Conventional reprocessing of endoscopes with high-level disinfection is labor intensive, expensive, delays the turnover of instruments, and involves potential exposure of personnel to toxic chemicals. We report a prospective clinical trial with rigorous microbiologic assessment of a novel disposable, sterile, polyurethane sheath, which can be easily and snugly applied over a nasopharyngoscope before performing the endoscopic procedure, with enzymatic cleansing and disinfection of the instrument with 70% ethanol following the procedure to determine whether the use of the novel sheath can provide reliable protection against bacterial contamination and obviate the need for routine high-level disinfection in reprocessing. Baseline cultures were obtained at 3 time periods from the control heads and insertion shafts of nasopharyngoscopes used in 100 clinical examinations: before application of the protective sheath and execution of the procedure; immediately after the procedure and removal of the sheath; and after enzymatic cleaning, disinfection with 70% ethanol, and drying. All 100 used sheaths and 20 unused sheaths were subjected to high-pressure leak testing to assess barrier integrity. Bacteria were detected on 16 control heads and 6 shafts prior to the procedure; from 13 heads and 1 shaft immediately following the nasopharyngoscopic procedure and sterile sheath removal; and none of the instruments following cleaning, ethanol disinfection, and drying. No sheath showed loss of barrier integrity on leak testing. Use of a high-quality, snugly fitting, sterile, disposable polyurethane sheath on a nasopharyngoscope during a clinical examination, combined with enzymatic detergent cleaning and disinfection with 70% ethanol, can provide a reliably decontaminated, patient-ready instrument, eliminating the need for high-level disinfection of endoscopes.

Ethanol disinfection of plastic-adherent micro-organisms

This study investigated the bactericidal effect of ethanol/water (70:30 vol:vol) against plastic-adherent organisms that commonly cause line infections. The experiments were performed in polycarbonate wells and all incubations were at 37 degrees C. Bacteria in broth were inoculated into wells and incubated (16, 40 and 72 h) before washing to remove non-adherent organisms and exposure to ethanol/water. Wells were then re-incubated with broth to detect surviving bacteria. All organisms incubated for 16 h were killed by 1h of exposure to 70% ethanol. After incubation for 40 h, 4h of exposure to ethanol was required to kill two strains of Candida albicans. Likewise, one of three of both Klebsiella pneumoniae and Pseudomonas aeruginosa, incubated for 72 h, showed growth after 1h of exposure to 70% ethanol but not after 4h of exposure. These results suggest that in contrast to log phase organisms, which are killed by ethanol/water solutions in seconds, plastic-adherent organisms are more resistant to the bactericidal activity of ethanol.

Nonfermenters under the Influence: Ethanol Disinfection of a Saline Dispenser Caused Misidentification by the Vitek 2 System Using the New GN Cards

Since its introduction in 1997, the Vitek 2 system (bioMerieux, Marcy-l'Etoile, France) has established itself as a stable and accurate automated system for rapid bacterial identification. Bacterial suspensions and test cards containing a panel of substrates are both placed into the instrument,

Analysis of sterilization protocols for peptide‐modified hydrogels

Concerns about the efficacy of ethanol disinfection for implanted biomaterials prompted investigation of an alternative sterilization process, ultraviolet irradiation, for terminal sterilization of N-isopropylacrylamide-based hydrogels containing biomimetic peptides. Ultraviolet irradiation is more easily applied on a laboratory scale than gamma irradiation or electron beam, two commercially utilized methods; thus, UVC irradiation was investigated as a low-cost sterilization procedure that might be performed in laboratories prior to in vivo studies. UVC irradiation at 400 muW/cm(2) for up to 15 h did not prevent growth of Escherichia coli within the hydrogels, while ethanol disinfection did prevent growth for the duration of the experiment (120 h). Furthermore, UVC irradiation caused progressive degradation of peptides containing the Arg-Gly-Arg (RGD) domain. UVC irradiation cannot be used as a terminal sterilization process for peptide-modified materials. The system used in this study is not intended to be adequate for evaluating the sterility of medical devices in accordance with current Good Manufacturing Practice (cGMP); however, it remains a useful, low-cost system for the preliminary evaluation of sterilization procedures in terms of their ability to eliminate pathogenic organisms while preserving the structure of biologically active molecules within in a laboratory setting. Ethanol treatment is still the preferred method for disinfection of bioactive materials containing peptides or UV-degradable groups.

Environmental contamination by multidrug-resistant Acinetobacter baumannii in an intensive care unit.

Contamination in an intensive care unit caused by multidrug-resistant Acinetobacter baumannii complex (MRAB)-colonized patients was evaluated using environmental and patient cultures. MRAB occurred in 21% of patients' cultures, 2.1% of 513 areas surrounding MRAB-patients, and one of 372 common areas. No transmission to other patients occurred. Barrier precautions and ethanol disinfection may prevent dissemination.