Wnt5b integrates Fak1a to mediate gastrulation cell movements via Rac1 and Cdc42

Focal adhesion kinase (FAK) mediates vital cellular pathways during development. Despite its necessity, how FAK regulates and integrates with other signals during early embryogenesis remains poorly understood. We found that the loss of Fak1a impaired epiboly, convergent extension and hypoblast cell migration in zebrafish embryos. We also observed a clear disturbance in cortical actin at the blastoderm margin and distribution of yolk syncytial nuclei. In addition, we investigated a possible link between Fak1a and a well-known gastrulation regulator, Wnt5b, and revealed that the overexpression of fak1a or wnt5b could cross-rescue convergence defects induced by a wnt5b or fak1a antisense morpholino (MO), respectively. Wnt5b and Fak1a were shown to converge in regulating Rac1 and Cdc42, which could synergistically rescue wnt5b and fak1a morphant phenotypes. Furthermore, we generated several alleles of fak1a mutants using CRISPR/Cas9, but those mutants only revealed mild gastrulation defects. However, injection of a subthreshold level of the wnt5b MO induced severe gastrulation defects in fak1a mutants, which suggested that the upregulated expression of wnt5b might complement the loss of Fak1a. Collectively, we demonstrated that a functional interaction between Wnt and FAK signalling mediates gastrulation cell movements via the possible regulation of Rac1 and Cdc42 and subsequent actin dynamics.

Implementation of human factors engineering approach to improve environmental cleaning and disinfection in a medical center

Background

Inadequate hospital cleaning may contribute to cross-transmission of pathogens. It is important to implement effective cleaning for the safe hospital environment. We conducted a three-phase study using human factors engineering (HFE) approach to enhance environmental cleanliness.

Methods

This study was conducted using a prospective interventional trial, and 28 (33.3%) of 84 wards in a medical center were sampled. The three-phases included pre-intervention analysis (Phase 1), implementing interventions by HFE principles (Phase 2), and programmatic analysis (Phase 3). The evaluations of terminal cleaning and disinfection were performed using the fluorescent marker, the adenosine triphosphate bioluminescence assay, and the aerobic colony count method simultaneously in all phases. Effective terminal cleaning and disinfection was qualified with the aggregate outcome of the same 10 high-touch surfaces per room. A score for each high-touch surface was recorded, with 0 denoting a fail and 10 denoting a pass by the benchmark of the evaluation method, and the total terminal cleaning and disinfection score (TCD score) was a score out of 100.

Results

In each phase, 840 high-touch surfaces were collected from 84 rooms after terminal cleaning and disinfection. After the interventions, the TCD score by the three evaluation methods all showed significant improved. The carriage incidence of multidrug-resistant organism (MDRO) decreased significantly from 4.1 per 1000 patient-days to 3.6 per 1000 patient-days (P = .03).

Conclusion

The HFE approach can improve the thoroughness and the effectiveness of terminal cleaning and disinfection, and resulted in a reduction of patient carriage of MDRO at hospitals. Larger studies are necessary to establish whether such efforts of cleanliness can reduce the incidence of healthcare-associated infection.

MicroRNAs regulate gene plasticity during cold shock in zebrafish larvae

Background

MicroRNAs (miRNAs) are critical regulators responding to acute environmental stresses in both plants and animals. By modulating gene expression, miRNAs either restore or reconstitute a new expression program to enhance cell tolerance to stresses. Cold shock is one of the stresses that can induce acute physiological responses and transcriptional changes in aquatic creatures. Previous genomic studies have revealed many cold-affected genes in fish larvae and adults, however, the role of miRNAs in acute cold response is still ambiguous. To elucidate the regulatory roles of miRNAs in the cold-inducible responses, we performed small RNA-seq and RNA-seq analyses and found potential cold regulatory miRNAs and genes. We further investigated their interactions and involvements in cold tolerance.

Results

Small RNA-seq and RNA-seq identified 29 up-/26 down-regulated miRNAs and 908 up-/468 down-regulated genes, respectively, in responding to cold shock for 4 h at 18 °C. miRNA and transcriptomic analyses showed these miRNAs and mRNAs are involved in similar biological processes and pathways. Gene ontology enrichment analyses revealed the cold-induced genes were enriched in pathways, including melanogenesis, GnRH pathway, circadian rhythm, etc. We were particularly interested in the changes in circadian clock genes that affect daily metabolism. The enrichment of circadian clock genes was also observed in previous fish cold acclimation studies, but have not been characterized. To characterize the functional roles of circadian clock genes in cold tolerance, we individually overexpressed selected clock genes in zebrafish larvae and found one of the core clock genes per2 resulted in better recovery from cold shock. In addition, we validated the interaction of per2 with its associate miRNA, dre-mir-29b, which is also cold-inducible. It suggests the transcription of per2 can be modulated by miRNA upon cold shock.

Conclusions

Collectively, our observations suggest that miRNAs are fine turners for regulating genomic plasticity against cold shock. We further showed that the fine tuning of core clock gene per2 via its associated miRNA, dre-mir-29b, can enhance the cold tolerance of zebrafish larvae.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-016-3239-4) contains supplementary material, which is available to authorized users.

Comparing visual inspection, aerobic colony counts, and adenosine triphosphate bioluminescence assay for evaluating surface cleanliness at a medical center

BACKGROUND

Environmental cleaning is essential in reducing microbial colonization and health care-associated infections in hospitals. However, there is no consensus for the standard method to assess hospital cleanliness, and comparisons of newer methodology, such as adenosine triphosphate bioluminescence assay, with the traditional methods are limited.

METHODS

A prospective study was conducted at a medical center between January 2013 and August 2013. In each selected room, 10-12 high-touch surfaces were sampled before and after terminal cleaning. The adequacy of cleaning was evaluated by visual inspection, aerobic colony counts (ACCs), and adenosine triphosphate (ATP) bioluminescence assay.

RESULTS

Eighty-five environmental surfaces from 8 rooms were evaluated by all 3 methods. The overall inadequacy defined by visual inspection, ACC, and ATP level was 11.8%, 20.0%, and 50.6% before cleaning and 4.7%, 5.9%, 21.2% after cleaning, respectively. A correlation between the ACC and ATP was found (r = 0.285, P < .001) using log10 values. Using ACCs <2.5 colony forming units/cm(2) as the cutoff for cleanliness, the ATP assay had better sensitivity than visual inspection (63.6% vs 27.3%). The receiver operating characteristics of the ATP assay indicated that the optimal ATP cutoff value was estimated to be 5.57 relative light units/cm(2).

CONCLUSION

ATP bioluminescence assay is a sensitive and rapid tool in evaluating the quality of terminal cleaning. We emphasize the value of using a quantitative method to monitor environmental cleaning at hospitals.

Assessing the thoroughness of hand hygiene: "seeing is believing"

The thoroughness of hand hygiene (HH) was evaluated using a simulation method in which health care workers (HCWs) rubbed their hands with a fluorescent substance, washed with water, and placed their hands under an ultraviolet detector to identify areas missed. Most residue points were located in the tips of the nails (38.6%), followed by fingertips (17.4%). This stress-free "seeing is believing" program can encourage HCWs' active participation in sustaining the HH culture of health care institutions.

Medical students' perceptions of their role as covert observers of hand hygiene

BACKGROUND

Medical students served as covert observers of hand hygiene (HH) compliance by health care workers (HCWs) during a recent 1-year study at a teaching hospital in Taiwan. This report describes the students' experience and their views of the major factors that led to good or poor compliance.

METHODS

Nine upper class medical students received a basic course in HH and attended a workshop using World Health Organization standard training materials. A standardized observation tool was used to collect data on HH performance by the HCWs. On completion of the study, structured face-to-face interviews were conducted to assess the students' experiences.

RESULTS

The medical students observed a total of 17,742 HH opportunities during the study period. Eight of the 9 students participated in the poststudy interviews. Overall, the students believed that they had gained considerable knowledge of the attitudes regarding HH compliance by nurses, physicians, and surgeons according to each of the 5 HH indications. Based on their experience, they recommended that compliance could be improved by ensuring an adequate supply of HH products and by promoting role modeling in the ward, reminding, education in small groups, and objective structured clinical examinations.

CONCLUSIONS

The opportunity for medical students to serve as covert observers broadened their knowledge of how infections are transmitted in hospitals and of the barriers that must be overcome to improve HCWs' HH compliance.

Calnexin is required for zebrafish posterior lateral line development

The lateral line is a mechanosensory system in fish and amphibians to detect local water flow and pressure. Development of the posterior lateral line (PLL) originates from the migrating PLL primordium (PLLP). The PLLP deposits neuromasts on the trunk during migration to the tail. Molecular dissection revealed that PLL development is associated with genes mediating cell adhesion, morphogenesis, neurogenesis and development, but the regulatory signaling network is far from completion. To further investigate candidate regulatory genes for lateral line development, we found using whole-mount in situ hybridization that calnexin, an endoplasmic reticular (ER) calcium-binding protein gene, is expressed in PLL neuromasts. Knockdown of calnexin using antisense morpholino oligonucleotides resulted in a dose-dependent reduction in neuromasts and hair cells of the PLL. Using a transgenic claudin b:gfp line, we observed a notably reduced PLLP size, but no significant migration defect in calnexin morphants. Finally, we discovered that the reduced PLLP is associated with a reduction in cell proliferation and an increase in ER stress-dependent apoptosis. These results suggest that calnexin is essential for neuromast formation during lateral line development in the zebrafish.

Patient empowerment in a hand hygiene program: differing points of view between patients/family members and health care workers in Asian culture

BACKGROUND

"Patient empowerment" is an important component of World Health Organization hand hygiene program, but little is known about the intentions and attitude of patients/families and health care workers (HCWs) regarding this.

METHODS

A cross-sectional survey using questionnaires was conducted in a tertiary teaching hospital in Taiwan to assess hand hygiene knowledge and the attitudes and intentions regarding patient empowerment among patients/families and HCWs.

RESULTS

Among patients/families, 95.4% (329/345) had positive attitudes regarding patient empowerment; however, only 67.2% (232/345) had the positive intention to remind HCWs about hand hygiene (P < .001). Risk factors for negative intention were being female (odds ratio [OR], 1.82; 95% confidence interval [CI]: 1.08-3.03), illiteracy (OR, 3.18; 95% CI: 0.86-11.7), and being patients/families in the pediatric department (OR, 1.86; 95% CI: 0.93-3.64). Among HCWs, the difference between positive attitude (81.1%; 714/880) and positive intention regarding being reminded about hand hygiene (62.8%; 553/880) was significant (P < .001). Risk factors for negative intention were age > 25 years (OR, 3.20; 95% CI: 1.51-6.81) and a negative attitude toward patient empowerment (OR, 10.00; 95% CI: 5.88-16.67).

CONCLUSION

There were significant gaps between attitude and intention regarding patient empowerment both among patients/families and HCWs. Special strategies targeting women, the pediatric population, or illiterate people may help improve patient/family participation. Additionally, hand hygiene education should be incorporated into early-stage medical/nursing education to create a facilitating environment. Patients/families and HCWs cooperation is needed to promote the hand hygiene program further.

Compliance of health care workers with hand hygiene practices: independent advantages of overt and covert observers

BACKGROUND

Evaluation and feedback of hand hygiene (HH) compliance are important elements of the WHO multimodal strategy for hospital infection control. Overt observation is recommended, but it may be confounded by Hawthorne effect. Covert observation offers the opportunity to decrease observer bias. In this study we conducted a one year hospital-wide HH promotion program that included medical students (MS) as covert observers.

METHODS

HH compliance for the five WHO indications was determined by trained and validated observers. The overt observers consisted of eleven infection control nurses (ICNs) and two unit HH ambassadors (UAs) in each of 83 wards. The covert observers consisted of nine MS during their rotating clinical clerkships. Feedback was provided to department heads and staff each quarter.

RESULTS

Of the 23,333 HH observations 76.0% were by MS, 5.3% by ICNs and 18.7% by UAs. The annual compliance rates were MS 44.1%, ICNs 74.4% and UAs 94.1%; P<0.001. The MS found significantly lower annual compliance rates for 4/5 HH indications compared to ICNs and UAs; P<0.05. The ICNs reported significantly improvement from the first to the fourth quarter; P<0.001. This was associated with feedback from the MS of very poor compliance by nurses during the first quarter.

CONCLUSIONS

Based on these findings we recommend a two-pronged approach to HH programs. The role of ICNs and UAs is to educate, serve as role models, establish, sustain good HH practices and provide direct feedback. The role of the covert observers is to measure compliance and provide independent feedback.