Antibiotic decision making in surgical intensive care: a qualitative analysis.

BACKGROUND: Antibiotic use in hospitals is high, particularly in surgical specialty and intensive care units. Antimicrobial stewardship programmes (ASPs) are increasingly intervening in antibiotic use by surgeons and intensivists. However, there is limited information on the features which characterize antibiotic decision making in the surgical intensive care unit (SICU), an area in hospital practice where critically ill surgery patients can be kept under close observation. AIM: To explore the features which characterize antibiotic decision making in the SICU. METHODS: A total of 160 h of ethnographic observation and 10 semi-structured interviews were conducted at two teaching hospitals in the USA. Data were analysed using thematic coding. FINDINGS: Three key characteristics of SICU practice with regard to antibiotic use were identified: (1) physical proximity makes SICU clinicians acutely aware of changes in patient status; (2) communication of patient status relies on active involvement by SICU clinicians; (3) SICU clinicians have contested and variable autonomy over antibiotic decisions. CONCLUSIONS: Antibiotic decision making in the SICU is a complex process involving multiple clinician teams with varying levels of physical proximity to and autonomy over patient cases. This study found that the SICU clinician team has increased physical proximity to patient cases but little autonomy over antibiotic decisions. If these characteristics are not considered, antimicrobial stewardship (AMS) interventions may have diminished success in addressing high levels of the antibiotic use in the SICU.

Electropermeabilization of nematode eggs for parasite deactivation.

The eggs of parasitic helminth worms are incredibly resilient - possessing the ability to survive changing environmental factors and exposure to chemical treatments - which has restricted the efficacy of wastewater sanitation. This research reports on the effectiveness of electroporation to permeabilize ova of Caenorhabditis elegans (C. elegans), a helminth surrogate, for parasite deactivation. This technique utilizes electric pulses to increase cell membrane permeability in its conventional application, but herein is used to open pores in nonparasitic nematode eggshells - the first report of such an application to the best knowledge of the authors. A parametric evaluation of electric field strength and total electroporation duration of eggs and worms in phosphate-buffered saline was performed using a 1 Hz pulse train of 0.01% duty cycle. The extent of pore formation was determined using a fluorescent label, propidium iodide, targeting C. elegans embryonic DNA. The results of this research demonstrate that electroporation increases eggshell permeability. This treatment, coupled with existing methods of electrochemical disinfection, could improve upon current attempts at the deactivation of helminth eggs. We discuss electroporation treatment conditions and likely modification of the lipid-rich permeability barrier within the eggshell strata.

Improved blackwater disinfection using potentiodynamic methods with oxidized boron-doped diamond electrodes.

Electrochemical disinfection (ECD) has become an important blackwater disinfection technology. ECD is a promising solution for the 2 billion people without access to conventional sanitation practices and in areas deficient in basic utilities (e.g., sewers, electricity, waste treatment). Here, we report on the disinfection of blackwater using potential cycling compared to potentiostatic treatment methods in chloride-containing and chloride-free solutions of blackwater (i.e., untreated wastewater containing feces, urine, and flushwater from a toilet). Potentiodynamic treatment is demonstrated to improve disinfection energy efficiency of blackwater by 24% and 124% compared to static oxidation and reduction methods, respectively. The result is shown to be caused by electrochemical advanced oxidation processes (EAOP) and regeneration of sp2-surface-bonded carbon functional groups that serve the dual purpose of catalysts and adsorption sites of oxidant intermediates. Following 24 h electrolysis in blackwater, electrode fouling is shown to be minimized by the potential cycling method when compared to equivalent potentiostatic methods. The potential cycling current density is 40% higher than both the static oxidative and reductive methods. This work enhances the understanding of oxygen reduction catalysts using functionalized carbon materials and electrochemical disinfection anodes, both of which have the potential to bring a cost-effective, energy efficient, and practical solution to the problem of disinfecting blackwater.

Selected Topics on the Synthesis, Properties and Applications of Multiwalled Carbon Nanotubes.

In summary, MWCNTs have been examined for a variety of electronic applications due to their unique structure and chemistry. Electrodes for field emission, energy and sensor applications hold particular interest. MWCNTs provide a very high surface area, relatively easy methods of surface modification, controllable and high concentration of reactive surface sites, and high specific capacitance. Combining MWCNTs with graphene structures, oxide and metal nanoparticles and certain polymers extends their performance and functionality. Such hybrid structures have been produced in situ during CNT growth and in two-step processes. Excellent progress on understanding the mechanisms of CNT growth has enabled numerous growth methods to all yield MWCNT structures in a variety of morphologies.

Zirconia-parylene multilayer thin films for enhanced fracture resistance of dental ceramics.

Recent research has shown that the application of specific thin films can enhance the material properties of a laminate construct. In this study, the effect of different mono/multilayered films on the strength of a ceramic specimen is demonstrated. It is well established that cracks can initiate and/or propagate from the internal surfaces of all-ceramic dental restorations. Modifying that surface by thin-film deposition might help increase clinical longevity and applicability. Specimens were divided into the following groups according to different surface treatments received: uncoated (control group), 10 microm yttria-stabilized zirconia (YSZ) thin film, 10 microm parylene thin film, 9.75 microm YSZ + 0.25 microm parylene film, and a multilayered film (five layers of 1.25 microm YSZ + 0.75 microm parylene). Depositions were performed using a radio-frequency magnetron sputter system (working pressure 15 mT, 150 degrees C, 30:1 Ar/O2 gas ratio) to produce the YSZ layers, and a vapour deposition process was used to produce the parylene layers. Flexural strength measurements were carried out by three-point bending (span = 10 mm) in a servo-electric material testing system in deioinized (DI) water (37 degrees C). The results showed that the strength of the specimen significantly increased with the deposition of all types of coating, showing the greatest increase with the multilayered film (approximately 32 per cent). It is hypothesized that a multilayer thin film (brittle/ductile) can promote crack deflection, causing strength enhancement of the brittle construct.

Surface modification for enhanced silanation of zirconia ceramics.

OBJECTIVE: The overall goal of this research was to develop a practical method to chemically modify the surface of high strength dental ceramics (i.e. zirconia) to facilitate viable, robust adhesive bonding using commercially available silanes and resin cements. METHODS: Investigation focused on a novel approach to surface functionalize zirconia with a Si(x)O(y) "seed" layer that would promote chemical bonding with traditional silanes. ProCAD and ZirCAD blocks were bonded to a dimensionally similar composite block using standard techniques designed for silica-containing materials (silane and resin cement). ZirCAD blocks were treated with SiCl4 by vapor deposition under two different conditions prior to bonding. Microtensile bars were prepared and subjected to tensile forces at a crosshead speed of 1 mm/min scanning electron microscopy was used to analyze fracture surfaces and determine failure mode; either composite cohesive failure (partial or complete cohesive failure within composite) or adhesive failure (partial or complete adhesive failure). RESULTS: Peak stress values were analyzed using single-factor ANOVA (p<0.05). Microtensile testing results revealed that zirconia with a surface treatment of 2.6 nm Si(x)O(y) thick "seed" layer was similar in strength to the porcelain group (control). Analysis of failure modes indicated the above groups displayed higher percentages of in-composite failures. Other groups tested had lower strength values and displayed adhesive failure characteristics. CONCLUSION: Mechanical data support that utilizing a gas-phase chloro-silane pretreatment to deposit ultra-thin silica-like seed layers can improve adhesion to zirconia using traditional silanation and bonding techniques. This technology could have clinical impact on how high strength dental materials are used today.

Avoiding risky sex partners: perception of partners' risks v partners' self reported risks.

BACKGROUND: Key strategies advocated for lowering personal risk of sexual exposure to STD/HIV include having fewer partners and avoiding risky partners. However, few studies have systematically examined how well people can actually discern their sex partners' risk behaviours. METHODS: We conducted face to face interviews with 151 heterosexual patients with gonorrhoea or chlamydial infection and 189 of their sex partners. Interviews examined the patients' perceptions of their sex partners' sociodemographic characteristics and risk behaviours. Patients' perceptions of partners were then sociometrically compared for agreement with partner self reports, using the kappa statistic for discrete variables and concordance correlation for continuous variables. RESULTS: Agreement was highest for perceived partner age, race/ethnicity, and duration of sexual partnership; and lowest for knowledge of partner's work in commercial sex, number of other sex partners, and for perceived quality of communication within the partnership. Index patients commonly underestimated or overestimated partners' risk characteristics. Reported condom use was infrequent and inconsistent within partnerships. CONCLUSION: Among people with gonorrhoea or chlamydial infection, patients' perceptions of partners' risk behaviours often disagreed with the partners' self reports. Formative research should guide development and evaluation of interventions to enhance sexual health communication within partnerships and within social networks, as a potential harm reduction strategy to foster healthier partnerships.

Relation of health literacy to gonorrhoea related care.

OBJECTIVE: To assess the relation between health literacy and receipt of a screening test for gonorrhoea in the past year. METHODS: Study design was multisite, cross sectional survey of subjects enrolled from clinics, from community based organisations, and by street intercept. Data were obtained using face to face interview. The dependent variable was self reported receipt of a test for gonorrhoea in the past year. Health literacy was measured by the Rapid Estimate of Adult Literacy in Medicine (REALM), recoded to represent 8th grade or lower reading or 9th grade and higher reading level. Statistical analyses were adjusted to account for selection bias in literacy assessment. RESULTS: 54% of the sample reported at least one gonorrhoea test in the previous year. 65% of the sample read at a 9th grade level or higher. REALM score was moderately correlated with the respondent's years of education. After adjustment for missing REALM data, past suspicion of gonorrhoea, self inspection for gonorrhoea, self efficacy for care seeking, REALM score of 9th grade reading level or higher, and younger age were independently associated with gonorrhoea testing in the previous year. For the average respondent, REALM reading grade level of 9th grade or higher is associated with a 10% increase in the probability of having a gonorrhoea test in the past year. CONCLUSIONS: Low literacy appears to pose a barrier to care for sexually transmitted infections such as gonorrhoea.

Single-dose gatifloxacin compared with ofloxacin for the treatment of uncomplicated gonorrhea: a randomized, double-blind, multicenter trial.

BACKGROUND: Treatment of gonorrhea is complicated by widespread resistance of Neisseria gonorrhoeae to antimicrobial agents of choice, including decreased susceptibility to ciprofloxacin. GOAL: To demonstrate the efficacy and safety of gatifloxacin, a novel 8-methoxy fluoroquinolone antibiotic, compared with ofloxacin in treating patients with uncomplicated gonococcal infection. STUDY DESIGN: In a double-blind, randomized (2:2:1), controlled trial, 340 men and 388 women with uncomplicated gonorrhea who were 16 years or older received a single oral dose of gatifloxacin (400 mg or 600 mg) or ofloxacin (400 mg). Primary analysis of efficacy was based on bacteriologic eradication from sites of infection. Secondary analyses examined clinical response and adverse event profiles. RESULTS: Bacteriologic eradication rates for gatifloxacin in evaluable men with urethral gonorrhea were 99% (400 mg) and 100% (600 mg) versus 100% for ofloxacin (n = 117, 122, and 55, respectively; P = ns). Eradication rates in evaluable women with endocervical gonorrhea were 99% for both 400 mg and 600 mg gatifloxacin versus 100% for ofloxacin (n = 101, 104, and 55, respectively; P = ns). Eradication rates were 100% for both rectal (n = 43) and pharyngeal (n = 31) infection across all treatment groups. All three drug regimens were well tolerated and exhibited similar clinical response profiles. CONCLUSION: Gatifloxacin is safe and effective as a single 400-mg or 600-mg dose for the treatment of uncomplicated gonorrhea. Similar efficacy rates were observed with the 400-mg and 600-mg doses. A single 400-mg dose can be recommended for treatment of uncomplicated gonorrhea.

Emergency department screening for asymptomatic sexually transmitted infections.

OBJECTIVES: This study assessed the prevalence and correlates of asymptomatic genital tract infection with Neisseria gonorrhoeae and Chlamydia trachomatis among emergency department patients. METHODS: Individuals seeking emergency department evaluation for nongenitourinary complaints provided urine samples for N gonorrhoeae and C trachomatis testing by ligase chain reaction and completed a sociodemographic and behavioral questionnaire. RESULTS: Asymptomatic N gonorrhoeae or C trachomatis was found in 9.7% of persons tested. Correlates of C trachomatis infection included younger age, residence in high-morbidity zip code areas, previous history of N gonorrhoeae or C trachomatis, and number of sex partners in the past year. CONCLUSIONS: Urine-based screening of asymptomatic emergency department patients detected significant numbers of N gonorrhoeae and C trachomatis infections. Targeted screening programs may contribute to community-level prevention and control of sexually transmitted infections.

Mechanical properties of a dental ceramic coated by RF magnetron sputtering.

Metal and ceramic thin film coatings were deposited onto a dental ceramic via radio frequency (RF) magnetron sputtering. The objectives of the study were to determine if a coherent interface could be produced between the coating and the substrate and if the coating significantly would improve the mechanical properties of the ceramic. Thin films of Au, Al, and AlN were deposited in this study. Mechanical testing results indicated that a significant improvement in flexural strength was observed with both Au and Al coatings while significant improvements in the flexural modulus were observed with all three materials. SEM analysis indicated that the interfaces were coherent and also suggested two mechanisms (crack bridging and crack blunting) that could be responsible for the enhanced mechanical properties.

To notify or not to notify: STD patients' perspectives of partner notification in Seattle.

BACKGROUND AND OBJECTIVES: To obtain patients' perspectives on why only some partners are notified in partner-notification programs, the cornerstone of sexually transmitted disease (STD) control, although low proportions of partners are located and evaluated. GOALS: To describe patterns of partner notification reported by persons with STD infection. STUDY DESIGN: In-depth interviews conducted in Seattle with 60 heterosexual men and women with gonorrhea, chlamydial infection, or nongonoccocal urethritis, and 19 men with gonorrhea reporting sex with men (MSM) were tape recorded, transcribed verbatim, and content analyzed. RESULTS: The typical notification pattern was to notify a main partner but not others. Least likely to be notified were partners perceived as transmitters, contacts preceding the onset of symptoms, the oral sex and anonymous contacts of MSM, one-time partners of men, and incarcerated and former partners of women. Fears among young heterosexual participants included gossip and violence (women). Fears among MSM included rejection. CONCLUSIONS: Partner-notification programs should develop innovative approaches for partners perceived as transmitters, oral-sex only contacts of MSM, and contacts preceding symptom onset.

Comparative epidemiology of heterosexual gonococcal and chlamydial networks: implications for transmission patterns.

OBJECTIVE: Networks of sex-partner interaction affect differential risk of acquiring sexually transmitted infections. The authors evaluated sociodemographic and behavioral factors that correlated with membership in networks of gonococcal and chlamydial transmission. METHODS: Face-to-face interviews were conducted with 127 patients with gonorrhea and 184 patients with chlamydia (index cases) and their named sex partners, as well as the partners of infected partners. Detailed information was obtained regarding demographic, behavioral, and sexual-history characteristics of all respondents. RESULTS: Gonococcal-network members differed significantly from chlamydial-network members in a number of demographic variables, including race or ethnicity, education, and unemployment status. Gonococcal-network members were more likely to report past history of crack-cocaine use, sexual assault, and having been in jail. Gonococcal-network members also reported having more sex partners during the past 1 year and 3 months than did chlamydial-network members. Gonococcal and chlamydial mixing matrices demonstrated assortativeness for sex partner selection by race or ethnicity but not by sexual activity level, and no systematic differences between networks were noted. Gonococcal networks were larger than chlamydial networks. CONCLUSIONS: Network analyses of gonococcal and chlamydial infections demonstrated significant differences in sociodemographic and behavioral variables. Further research is required to delineate specific predictors of network membership among persons at risk for sexually transmitted infections.

Urine screening for gonococcal and chlamydial infections at community-based organizations in a high-morbidity area.

BACKGROUND: Increasing availability of urine testing for Neisseria gonorrhoeae (GC) and Chlamydia trachomatis (CT) offers expanded opportunities to collaborate with community-based organizations (CBOs) to screen high-risk populations for sexually transmitted diseases (STDs). GOAL: To determine the prevalence and correlates of genital tract gonococcal and chlamydial infection among CBO clients, and to assess the feasibility of implementing widespread community-based STD screening programs. DESIGN: Free, voluntary, confidential first-catch urine screening was conducted at 20 CBOs serving disadvantaged populations in St. Louis, MO. Brief demographic, behavioral, and sexual contact data were obtained from all participants. Urine samples were tested by ligase chain reaction (LCR). Persons testing positive were promptly notified and directed to seek treatment. RESULTS: A GC and/or CT infection was identified in 24 of 277 persons (8.7%) screened; 2 persons were infected with GC only, 17 with CT only, and 5 with GC and CT. Treatment was documented for 22 persons (91.7%) testing positive. The highest rates of infection were found at shelters (12.3%) and residence facilities (11.1%). Costs of screening were $38 per sample collected and $453 per case identified. CONCLUSION: Community-based urine testing successfully identified GC and CT infections, and was well accepted by community members and CBOs. Community-based screening can significantly impact STD epidemiology by facilitating early detection, treatment, and interruption of transmission.

Practice patterns for the elicitation of sexual history, education, and counseling among providers of STD services: results from the gonorrhea community action project (GCAP).

BACKGROUND: The frequently asymptomatic nature and high incidence of severe complications of sexually transmitted diseases (STD) calls for targeted efforts to identify those at greatest risk. Earlier studies have shown inconsistencies regarding STD evaluation by primary care clinicians and physicians. However, the literature regarding the consistency of practice patterns regarding elicitation of sexual history is limited. We examined practice patterns for the elicitation of sexual history among providers across seven sites nationwide. METHODS: As part of a multisite study to encourage health seeking for populations specifically at risk for gonorrhea (GC) and other STDs, semistructured interviews that included questions regarding sexual history elicitation were conducted with 208 service providers in a total of 121 publicly and privately funded clinics, managed care organizations (MCOs), hospital clinics, community- and school-based clinics in Denver, New York, Los Angeles, Birmingham, St. Louis, Indianapolis, and Prince Georges County, MD. RESULTS: Among the providers interviewed, practice patterns for the elicitation of sexual history were inconsistent. Sexual histories were described as routine (i.e., solicited from every client regardless of reason for visit) in 57% of sites. Providers most frequently asked clients their number of sex partners (57%), their contraceptive history (55%), and STD history (34%). Client discomfort among 46% and provider discomfort among 13% was cited as barriers to the elicitation of sexual history. A quarter (26%) of providers agreed that the elicitation of sexual history can be fostered by improved provider communication skills and 16% agreed increasing training and experience for providers is needed. CONCLUSIONS: These findings suggest that interventions with providers to standardize sexual history elicitation can help to reduce barriers to prevention, diagnosis, and treatment of STD.

Sexual mixing patterns in the spread of gonococcal and chlamydial infections.

OBJECTIVES: This study sought to define, among sexually transmitted disease (STD) clinic attendees, (1) patterns of sex partner selection, (2) relative risks for gonococcal or chlamydial infection associated with each mixing pattern, and (3) selected links and potential and actual bridge populations. METHODS: Mixing matrices were computed based on characteristics of the study participants and their partners. Risk of infection was determined in study participants with various types of partners, and odds ratios were used to estimate relative risk of infection for discordant vs concordant partnerships. RESULTS: Partnerships discordant in terms of race/ethnicity, age, education, and number of partners were associated with significant risk for gonorrhea and chlamydial infection. In low-prevalence subpopulations, within-subpopulation mixing was associated with chlamydial infection, and direct links with high-prevalence subpopulations were associated with gonorrhea. CONCLUSIONS: Mixing patterns influence the risk of specific infections, and they should be included in risk assessments for individuals and in the design of screening, health education, and partner notification strategies for populations.

Sexually transmitted disease acquisition among women infected with human immunodeficiency virus type 1.

Recent evidence suggests that sexually transmitted diseases (STDs) enhance the transmission of human immunodeficiency virus (HIV) type 1. In 143 HIV-infected women enrolled in a university-based longitudinal HIV clinic over 16 months (mean), the STD point prevalence was examined at enrollment and the cumulative prevalence was calculated at follow-up. At enrollment, 35 women (25%) had > or = 1 STD. These included trichomoniasis in 16 women (11%); syphilis, 9 (6%); genital herpes, 8 (6%); gonorrhea, 5 (4%); chlamydia, 5 (4%); genital warts, 2 (1%); and pelvic inflammatory disease (PID), 1 (1%). STDs were found in 55 (42%) of the 125 patients who returned for at least one follow-up visit: trichomoniasis in 23 (18%); genital herpes, 20 (12%); gonorrhea, 9 (7%); syphilis, 7 (6%); genital warts, 7 (6%); chlamydia, 5 (4%); and PID, 4 (3%). Despite counseling at both enrollment and follow-up, these women had a very high cumulative prevalence of STDs, indicating persistent high-risk sexual behavior.

Sexual mixing patterns of patients attending sexually transmitted diseases clinics.

BACKGROUND: Theorectical studies have highlighted the importance of patterns of choice of sex partner in the transmission and persistence of sexually transmitted diseases (STDs). GOAL: To describe reported patterns of sexual mixing according to numbers of sex partners in STD clinics. STUDY DESIGN: Patients attending public health clinics in Seattle, Washington were interviewed about their own and their partners' behaviors. RESULTS: Throughout, patterns of sexual mixing were weakly assortative. Across activity groups, many respondents believed their partners had no other sexual contacts. Those with three or more partners frequently perceived their partners to have three or more partners as well. CONCLUSIONS: Assortatively mixing persons of high sexual activity makes the persistence of STDs within a population likely (i.e., they act as a "core group"). Additionally, because mixing is not highly assortative (like with like), a steady trickle of infection from members of the core group will pass to other segments of the population.

Brief experimental analysis of stimulus prompts for accurate responding on academic tasks in an outpatient clinic.

Brief multielement designs were used to examine the effects of specific instructional strategies on accuracy of academic performance during outpatient evaluations of 4 children with learning disorders. Instructional strategies that improved accuracy on academic tasks were identified for all participants. These results suggest that the application of experimental analysis methodologies to instructional variables may facilitate the identification of stimulus prompts that are associated with enhanced academic performance.