Assessment of microbial bioburden on portable medical equipment in a hospital setting.

Objectives: Although routine disinfection of portable medical equipment is required in most hospitals, frontline staff may not be able to disinfect portable medical equipment at a rate that adequately maintains low bioburden on high-use equipment. This study quantified bioburden over an extended time period for two types of portable medical equipment, workstations on wheels and vitals machines, across three hospital wards. Methods: Bioburden was quantified via press plate samples taken from high touch surfaces on 10 workstations on wheels and 5 vitals machines on each of 3 medical surgical units. The samples were taken at three timepoints each day over a 4-week period, with random rotation of timepoints and portable medical equipment, such that frontline staff were not aware at which timepoint their portable medical equipment would be sampled. The mean bioburden from the different locations and portable medical equipment was estimated and compared with Bayesian multilevel negative binomial regression models. Results: Model estimated mean colony counts (95% credible interval) were 14.4 (7.7-26.7) for vitals machines and 29.2 (16.1-51.1) for workstations on wheels. For the workstations on wheel, colony counts were lower on the mouse, 0.22 (0.16-0.29), tray, 0.29 (0.22, 0.38), and keyboard, 0.43 (0.32-0.55), when compared to the arm, as assessed by incident rate ratios. Conclusions: Although routine disinfection is required, bioburden is still present across portable medical equipment on a variety of surfaces. The difference in bioburden levels among surfaces likely reflects differences in touch patterns for the different portable medical equipment and surfaces on the portable medical equipment. Although the association of portable medical equipment bioburden to healthcare-associated infection transmission was not assessed, this study provides evidence for the potential of portable medical equipment as a vector for healthcare-associated infection transmission despite hospital disinfection requirements.

Effect of a "feedback prompt" from a disinfection tracking system on portable medical equipment disinfection.

BACKGROUND: Portable medical equipment (PME) may contribute to transmission of multidrug-resistant organisms without proper disinfection. We studied whether a Disinfection Tracking System (DTS) with feedback prompt, attached to PME, can increase the frequency of PME disinfection. METHODS: DTS devices were placed on 10 workstations-on-wheels (WOWs) and 5 vitals machine (VM). After a 25 day "screen-off" period, the DTS device screens were turned on to display the number of hours since the last recorded disinfection event for a 42 day period. We used a Bayesian multilevel zero-inflated negative binomial model to compare the number of events in the display "screen-off" to the "screen-on" period. RESULTS: During the "screen-off" period, there were 1.26 and 0.49 mean disinfection events and during the "screen-on" period, there were 1.76 and 0.50 mean disinfection events for WOWs and VM, respectively, per day. The model estimated mean events per device per day in the the "screen-on" period for WOW's were 1.32 (1.10 - 1.57) times greater than those in the "screen-off" period and the "screen-on" period for VM devices was 1.37 (0.89 - 2.01) times greater than those in the "screen-off" period. CONCLUSIONS: The rate of disinfection events for WOWs increased following the implementation of the DTS feedback prompt.

Capturing portable medical equipment disinfection data via an automated novel disinfection tracking system.

BACKGROUND: Portable Medical Equipment (PME) such as workstations-on-wheels (WOWs) and vital signs machines (VMs) have been linked to healthcare-associated infections. Routine visual monitoring of PME disinfection is difficult. An automated Disinfection Tracking System (DTS) was used to record and report the number of disinfection events of PME in a hospital setting. METHODS: The study was conducted in 2 acute-care units for 25-days to determine the pattern of recorded events from DTS on PME. Devices record disinfection events as moisture events and automatically store on a central database. DTS devices with "screen-on" feedback and "screen-off" devices with no display were placed on 10 WOWs and 5 VMs on separate units. RESULTS: A total of 421 moisture events were recorded for the "screen-on" and 345 for the "screen-off", during the 25-day implementation period on the 2 different hospital units. The highest number of events occurred between 6:00am-7:00am, with 69 & 75 moisture events recorded for Units 1 and 2, respectively. CONCLUSIONS: The pattern of disinfection events for WOWs and VMs demonstrated that most events occurred regularly at the times corresponding with nursing shift change. The DTS has the potential to continuously record, and report data related to PME disinfection.

Current understanding of the surface contamination and contact transmission of SARS-CoV-2 in healthcare settings.

The novel coronavirus disease (COVID-19) has rapidly spread across the world and was subsequently declared as a pandemic in 2020. To overcome this public health challenge, comprehensive understanding of the disease transmission is urgently needed. Recent evidences suggest that the most common route of transmission for SARS-CoV-2 is likely via droplet, aerosol, or direct contact in a person-to-person encounter, although the possibility of transmission via fomites from surfaces cannot be ruled out entirely. Environmental contamination in COVID-19 patient rooms is widely observed due to viral shedding from both asymptomatic and symptomatic patients, and SARS-CoV-2 can survive on hospital surfaces for extended periods. Sequence of contact events can spread the virus from one surface to the other in a hospital setting. Here, we review the studies related to viral shedding by COVID-19 patients that can contaminate surfaces and survival of SARS-CoV-2 on different types of surfaces commonly found in healthcare settings, as well as evaluating the importance of surface to person transmission characteristics. Based on recent evidences from the literature, decontamination of hospital surfaces should constitute an important part of the infection control and prevention of COVID-19.

Classical and alternative disinfection strategies to control the COVID-19 virus in healthcare facilities: a review.

The coronavirus disease COVID-19 has spread throughout the world and has been declared as a pandemic by the World Health Organization on March 11th, 2020. The COVID-19 is caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). One possible mode of virus transmission is through surfaces in the healthcare settings. This paper reviews currently used disinfection strategies to control SARS-CoV-2 at the healthcare facilities. Chemical disinfectants include hypochlorite, peroxymonosulfate, alcohols, quaternary ammonium compounds, and hydrogen peroxide. Advanced strategies include no-touch techniques such as engineered antimicrobial surfaces and automated room disinfection systems using hydrogen peroxide vapor or ultraviolet light.

Effectiveness of Copper-Impregnated Solid Surfaces on Lowering Microbial Bio-Burden Levels in an Acute Care Hospital.

BACKGROUND: Microbial bio-burden on high-touch surfaces in patient rooms may lead to acquisition of health care-associated infections in acute care hospitals. This study examined the effect of a novel copper-impregnated solid material (16%-20% copper oxide in a polymer-based resin) on bacterial contamination on high-touch surfaces in patient rooms in an acute care hospital. METHODS: Five high-touch surfaces were sampled for aerobic bacterial colonies (ABCs) 3 times per day over a 3-day period in 16 rooms with copper installed and 16 rooms with standard noncopper laminate installed on high-touch surfaces. A Bayesian multilevel negative binomial regression model was used to compare ABC plate counts from copper-impregnated surfaces with standard hospital laminate surfaces. RESULTS: The mean and median (interquartile range [IQR]) ABC counts from copper-impregnated surfaces were 25.5 and 11 (4-27), and for standard hospital laminate surfaces they were 60.5 and 29 (10-74.3). The negative binomial regression model-estimated incidence rate for ABC counts on plates taken from copper-impregnated surfaces was 0.40 (0.21-0.70) times the incidence rate of ABC counts on plates taken from standard hospital laminate surfaces. CONCLUSIONS: Copper-impregnated solid surfaces may reduce the level of microbial contamination on high-touch surfaces in patient rooms in the acute care environment, as our study demonstrated a decline in microbial bio-burden on samples taken from copper-impregnated compared with standard hospital laminate high-touch surfaces.

A previously unrecognized kanosamine biosynthesis pathway in Bacillus subtilis.

The ntd operon in Bacillus subtilis is essential for biosynthesis of 3,3'-neotrehalosadiamine (NTD), an unusual nonreducing disaccharide reported to have antibiotic properties. It has been proposed that the three enzymes encoded within this operon, NtdA, NtdB, and NtdC, constitute a complete set of enzymes required for NTD synthesis, although their functions have never been demonstrated in vitro. We now report that these enzymes catalyze the biosynthesis of kanosamine from glucose-6-phosphate: NtdC is a glucose-6-phosphate 3-dehydrogenase, NtdA is a pyridoxal phosphate-dependent 3-oxo-glucose-6-phosphate:glutamate aminotransferase, and NtdB is a kanosamine-6-phosphate phosphatase. None of these enzymatic reactions have been reported before. This pathway represents an alternate route to the previously reported pathway from Amycolatopsis mediterranei which derives kanosamine from UDP-glucose.

Respiratory hygiene in emergency departments: compliance, beliefs, and perceptions.

BACKGROUND: Low respiratory hygiene compliance among health care workers of emergency departments has become a major concern in the spread of respiratory infections. Our objective was to determine the compliance with respiratory hygiene of triage nurses at 2 university hospital centers and to identify factors influencing compliance to the respiratory hygiene principles of emergency health care workers. METHODS: A 2-part, cross-sectional, descriptive study was conducted at 2 training centers. An anonymous observation of compliance with respiratory hygiene by triage emergency nurses was performed. A self-administered, voluntary questionnaire on attitudes, perceptions, and knowledge of respiratory hygiene guidelines was distributed to the health care workers at the emergency department of the 2 hospital sites. RESULTS: Median objective compliance with respiratory hygiene measures of triage nurses was 22% (interquartile range [IQR], 11%-33%). Median perceived compliance of the health care workers was 68% (IQR, 61%-79%). Median actual knowledge score was 75% (IQR, 75%-100%). Overall, 91.9% of respondents believed that the mask was an effective preventive measure. The main obstacles toward mask wearing by the health care worker were "tendency to forget" (37.8%) and "discomfort" (35.1%). CONCLUSION: The compliance rate at our institution is very low. We identified a few factors affecting adherence to respiratory hygiene measures that are of potential use in targeting groups and formulating recommendations.

Performance evaluation of the new ADVIA Centaur system cyclosporine assay (single-step extraction).

BACKGROUND: Cyclosporine (CsA) monitoring is essential for transplant success. We report a performance study of the recently released, fully automated Siemens ADVIA Centaur CsA assay. METHODS: Whole blood samples from 248 transplant patients were prepared using a new 1-step extraction method. Performance evaluations vs. HPLC-tandem MS (LC-MS/MS), Abbott TDx and AxSYM assays were conducted according to CLSI EP5-A2 and EP9-A2 guidelines. RESULTS: The correlation coefficient for LC-MS/MS and ADVIA Centaur was > or = 0.97 at each site, and for each transplant type. Regression analysis yielded y=0.94x+19 for all sites: 95% CI=0.91-0.96 (slope) and 10-28 (intercept). Absolute and relative bias was minimal for C0 and C2 sampling. Centaur vs. Abbott TDx and AxSYM assays: y = 0.72x+6, r = 0.98, 95% CI = 0.70-0.73 (slope), 3-9 (intercept); and y = 0.69x+18, r = 0.97, 95% CI = 0.67-0.71 (slope), 8-27(intercept). Within run CVs were 4.5%-7.1%, total CVs were 5.3%-7.7%. CONCLUSIONS: The ADVIA Centaur assay compared favorably with LC-MS/MS and Abbott assays, displaying good correlation for all transplant types and methods.

CD47 expression on T cell is a self-control negative regulator of type 1 immune response.

The cytokine milieu and dendritic cells (DCs) direct Th1 development. Yet, the control of Th1 polarization by T cell surface molecules remains ill-defined. We here report that CD47 expression on T cells serves as a self-control mechanism to negatively regulate type 1 cellular and humoral immune responses in vivo. Th2-prone BALB/c mice that lack CD47 (CD47(-/-)) displayed a Th1-biased Ab profile at steady state and after immunization with soluble Ag. CD47(-/-) mice mounted a T cell-mediated exacerbated and sustained contact hypersensitivity (CHS) response. After their adoptive transfer to naive CD47-deficient hosts 1 day before immunization with soluble Ag, CD47(-/-) as compared with CD47(+/+)CD4(+) transgenic (Tg) T cells promoted the deviation of Ag-specific T cell responses toward Th1 that were characterized by a high IFN-gamma:IL-4 cytokine ratio. Although selective CD47 deficiency on DCs led to increased IL-12p70 production, CD47(-/-)Tg T cells produced more IFN-gamma and displayed higher T-bet expression than CD47(+/+) Tg T cells in response to OVA-loaded CD47(-/-) DCs. CD47 as part of the host environment has no major contribution to the Th1 polarization responses. We thus identify the CD47 molecule as a T cell-negative regulator of type 1 responses that may limit unwanted collateral damage to maximize protection and minimize host injury.

Ankle plantarflexor strength and endurance in 7-9 year old children as measured by the standing single leg heel-rise test.

BACKGROUND AND PURPOSE: The standing single-leg (SSL) heel-rise test is a measure of plantarflexor strength and endurance. However, reference values have yet to be determined for children. The purposes of this study were to: (1) determine the average number, minimum number (cut-off score) of SSL heel-rises for healthy, 7-9 year old children, (2) examine the influence of age, gender, height, weight, and physical activity characteristics upon the number of heel-rises completed, (3) examine inter-rater reliability, and (4) examine reliability between the number of repetitions counted by observation, and by video-analysis. METHOD: A total of ninety-five children, aged 7-9, performed SSL heel-rises until fatigue. The number of heel-rises were counted by two examiners and was determined from videotape. RESULTS: The children completed an average of 36 +/- 18 SSL heel-rises (COV = 50%). Age, gender, height, weight, or activity level had no significant effect upon heel-rise performance. Excellent inter-rater reliability (ICC = 0.99), reliability between the motion analysis system and the examiners (ICC = 0.93), was established. Discussion, CONCLUSION: Therapist visual observation can determine heel-rise count as accurately as when using a motion analysis system. Children who have functional limitations, who perform 13 or fewer heel-rises should repeat the SSL heel-rise test at a later date and/or perform other tests to confirm the plantarflexion muscle strength-endurance impairment prior to initiating an intervention program.

Development of a computerized intervertebral motion analysis of the cervical spine for clinical application.

OBJECTIVE: The objective of this study was to develop a measurement method that could be implemented in chiropractic for the evaluation of angular and translational intervertebral motion of the cervical spine. METHODS: Flexion-extension radiographs were digitized with a scanner at a ratio of 1:1 and imported into a software, allowing segmental motion measurements. The measurements were obtained by selecting the most anteroinferior point and the most posteroinferior point of a vertebral body (anterior and posterior arch, respectively, for C1), with the origin of the reference frame set at the most posteroinferior point of the vertebral body below. The same procedure was performed for both the flexion and extension radiographs, and the coordinates of the 2 points were used to calculate the angular movement and the translation between the 2 vertebrae. RESULTS: This method provides a measure of intervertebral angular and translational movement. It uses a different reference frame for each joint instead of the same reference frame for all joints and thus provides a measure of motion in the plane of each articulation. The calculated values obtained are comparable to other studies on intervertebral motion and support further development to validate the method. CONCLUSION: The present study proposes a computerized procedure to evaluate intervertebral motion of the cervical spine. This procedure needs to be validated with a reliability study but could provide a valuable tool for doctors of chiropractic and further spinal research.

Downregulation of the PI3K/Akt survival pathway in cells with deregulated expression of c-Myc.

Oncogenic transformation leads to an increased sensitivity to apoptosis, a characteristic that is selectively lost during tumor progression. The sensitization process affects the mitochondrial pathway of apoptosis through signaling events that are poorly defined. We previously showed that a deregulated expression of c-Myc in cells treated with toxic agents caused an enhanced activation of p38 that acts in a death-promoting pathway. Here, we show that deregulated expression of c-Myc causes a severe reduction in the basal activity of Akt, which was further accelerated by serum deprivation. Furthermore, c-Myc expression repressed the activation of Akt induced by the toxic agents doxorubicin, cisplatin and H(2)O(2), and also by the physiological agonists PDGF and insulin. We determined that the activation of Akt was inhibited as a result of the action of c-Myc upstream of phosphatidylinositol 3-kinase (PI3K) activation. c-Myc overexpression impaired the induced association of the p85 subunit of PI3K with phosphotyrosine containing proteins, causing a reduction in the activation of PI3K and recruitment of Akt to the membrane. Inhibiting Akt in addition to enhancing p38 further exacerbate the imbalance between the death and survival signals and results in an enhanced sensitivity to apoptosis.

Identification of new thyroid hormone-regulated genes in rat brain neuronal cultures.

As a first approach to study the molecular mechanisms that underlie the effects of thyroid hormones on the developing brain, we used a cDNA microarray technology to identify early thyroid hormone-regulated genes in brain neuronal cultures treated with tri-iodothyronine (T3) for 3 h. We identified three genes that were up-regulated by T3, basic transcription element-binding protein, nuclear pore glycoprotein and bone morphogenetic protein-4 and one that was down-regulated, the neuronal apoptosis-inducing gene. We confirmed that these genes were also regulated by the thyroid state in the developing brain. Our findings enrich our knowledge of signaling pathways regulated by thyroid hormones and open new avenues for studying the molecular mechanisms of thyroid hormones in the developing brain.

Validation of a Questionnaire to Screen University Students for Learning Disabilities.

Learning disabilities (LD) may cause academic failures among university students, but minor accommodations may in some instances allow students to progress satisfactorily. The current study validates a questionnaire for detecting students likely to have an LD. University students, 57 with a documented LD and 134 without, completed a Likert-scale questionnaire to assess the degree of self-perceived difficulty for 50 learning or testing situations. Wilcoxon rank sum test, separate logistic regression models, and determination of the best joint set of predictors of LD were carried out. The mean per-item questionnaire score was higher in the LD group (p < 0.0001); 47 individual items were significant predictors (i.e., p < 0.05) of LD status. The best joint set of predictors consisted of items dealing with word pronunciation, comprehending mathematical word problems, formulating summaries, spelling, slow reading rate, finishing tests in the allotted time, note-taking in lectures, and falling asleep while reading. Incorporating responses to these eight items, a formula was derived to determine the probability of LD. Taking 0.26 as the threshold for predicting the presence of an LD, the sensitivity of the questionnaire was 88%, the specificity was 87% for this population. The questionnaire could be an effective screening tool to detect university or professional students who should consider comprehensive testing for LD.